Product irradiation device and method of irradiating products using the same

Information

  • Patent Grant
  • 6437344
  • Patent Number
    6,437,344
  • Date Filed
    Wednesday, August 25, 1999
    25 years ago
  • Date Issued
    Tuesday, August 20, 2002
    22 years ago
Abstract
A product irradiation device includes an enclosure and an irradiator shell disposed in the enclosure. The shell comprises a wall or walls enclosing an irradiation source and a transport channel extending from an inlet port to an outlet port of the shell. The enclosure has an entry opening, communicating with the inlet port, through which products are introduced in succession into the transport channel from external of the enclosure. The enclosure has an exit opening, communicating with the outlet port, through which products discharged in succession from the transport channel are transported to a location external of the enclosure, the exit opening being disposed at a location different from the entry opening. The shell has a non-moving transport surface defined by a surface or surfaces of the wall or walls and upon which the products are advanced in fixed increments through the transport channel past the irradiation source. A plurality of linear actuators are provided in or on the shell for advancing the products through the transport channel. A method of irradiating products includes the steps of introducing products in succession into a transport channel of an irradiator shell, moving the products relative to and upon a non-moving transport surface of the shell such that the products are moved past an irradiation source in the shell and discharging the products in succession through an outlet port of the shell disposed at a location different from the inlet port.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to product irradiation devices and, more particularly, to irradiation devices for irradiating products prior to consumption and/or use and to methods of irradiating products using irradiation devices.




2. Brief Description of the Prior Art




It has become desirable to irradiate various types of products, such as medical products and food products, to enhance the quality of the products prior to consumption and/or use thereof. Irradiation of medical and food products has been recognized as an effective means of sterilizing such products. More typically, irradiation has been used for pasteurization of food products, including meat, poultry, produce, cereal and canned goods, to destroy harmful parasites, bacteria and other pathogens and microorganisms in the food products, thusly increasing their safety for human consumption while not necessarily eradicating all micro-organisms. Irradiated food products have also been found to resist deterioration and to possess longer shelf lives. In the case of produce, such as onions and potatoes, irradiation has been found to inhibit the growth of undesired sprouts on the produce. In the case of meat, the need for irradiation has intensified in view of the prevalence of human disease contracted via consumption of contaminated meat.




In the field of product irradiation, the use of radioactive isotopes, electron beams and X-rays as the sources of radiation has been contemplated. Various devices have been proposed for irradiating products to enhance the quality thereof, as exemplified by U.S. Pat. No. 1,876,737 to Opp, U.S. Pat. No. 3,142,759 to Jefferson et al., U.S. Pat. No. 3,411,002 to Armel, U.S. Pat. No. 3,454,761 to Brunner, U.S. Pat. No. 3,641,342 to Armel et al., U.S. Pat. No. 3,686,502 to Sieber, U.S. Pat. No. 4,066,907 to Tetzlaff, U.S. Pat. No. 4,864,595 to Barrett and U.S. Pat. No. 5,001,352 to Tetzlaff. In particular, the Armel, Tetzlaff ('907) and Barrett patents contemplate the irradiation of foodstuffs, as well as animal feed and medical articles, to effect sterilization, to inhibit deterioration and to destroy bacteria. The Opp patent contemplates the in situ irradiation of vegetation in order to kill parasites. The Opp patent relates to X-ray irradiation while the remainder of the cited patents relate to radioactive isotope irradiation. The subject invention is based on employing radioactive isotopes to irradiate products, as opposed to electron beam (E-beam) or X-ray devices.




Prior art product irradiation devices employing radioactive isotopes possess numerous disadvantages and drawbacks. In particular, such prior art product irradiation devices typically rely on complex transport mechanisms for moving the products past irradiation sources within the irradiation devices. Such complex transport mechanisms typically include moving conveyors, platforms, monorails and/or elevators, for example, disposed in high radiation zones of the product irradiation devices. Such transport mechanisms take up valuable space, undesirably add weight and increase the complexity and cost of the product irradiation devices. In addition, exposure of the transport mechanisms to radiation presents significant maintenance and repair problems related to the impairment or degradation of the transport mechanisms due to radiation exposure and the difficulty involved in accessing the transport mechanisms within the high radiation zones. The transport mechanisms typically include numerous moving mechanical parts that require the presence of lubricants, such as oil or grease, in the high radiation zones, in which case maintenance requirements are significantly increased. Accordingly, prior art product irradiation devices are generally associated with frequent down times for troubleshooting and maintenance, during which normal operation of the product irradiation devices must be suspended.




Another drawback of many prior art product irradiation devices employing radioactive isotopes is that the products being irradiated are moved along complex or circuitous prescribed paths through the irradiation devices. In many prior art product irradiation devices, the products are moved in multiple columns and/or rows, are moved between successive levels or tiers and/or are transferred between different conveyors, platforms or other mechanical structures as they are moved along the prescribed paths. Furthermore, some prior art product irradiation devices require that the products be individually rotated, repositioned or reoriented in addition to being moved in the prescribed paths through the irradiation devices. The complexity of the prescribed paths for the products through the irradiation devices, as well as the mechanical structures associated with moving the products in the prescribed paths and/or rotating, repositioning or reorienting the products individually, greatly increase the risk of malfunction and damage to the products being irradiated. Furthermore, in some prior art product irradiation devices, the products to be irradiated must be placed in special containers or bins prior to entering the irradiation devices, thusly undesirably complicating the irradiation operations and adding to the cost thereof. Many prior art product irradiation devices also require very complex indexing and timing systems to effect movement of the products through the irradiation devices. In order to effect the necessary indexing and timing, many prior art product irradiation devices require the presence of a very large number of products or “dummy” products in the irradiation devices.




An additional disadvantage associated with some prior art product irradiation devices is that the product irradiation devices are extremely bulky, heavy and cannot be moved from place to place. In particular, some product irradiation devices are located remote from the sources, such as manufacturing or processing facilities, of the products to be irradiated. This requires that the products to be irradiated be brought to the product irradiation devices rather than the product irradiation devices being brought to the sources of the products. Furthermore, some prior art product irradiation devices have the additional drawback of permitting human access to the interiors of the product irradiation devices via entry and/or exit ports through which the products enter and/or exit the product irradiation devices. In some prior art product irradiation devices, the entry and exit ports are disposed adjacent or close to one another or at substantially the same location on the product irradiation devices, thusly creating the risk that non-irradiated products entering the irradiation devices and irradiated products exiting the irradiation devices will become intermingled or mixed up with one another. Accordingly, some products may be inadvertently passed through the irradiation devices more than once and other products may not be irradiated at all. Some prior product irradiation devices have as a disadvantage the requirement that the irradiation sources be located in a water pool when not in use. Consequently, the sources are undesirably subjected to thermal transients, and complex lifting/lowering devices are needed.




Accordingly, the need exists for a product irradiation device employing radioactive isotopes and wherein the number of moving mechanical parts and the prescribed path for the products through the irradiation device are simplified and minimized while allowing products to be continuously irradiated at or proximate their source with minimal maintenance and repair and without inadvertent intermingling of irradiated and nonirradiated products.




SUMMARY OF THE INVENTION




Accordingly, it is a primary object of the present invention to overcome the aforementioned disadvantages of prior product irradiation devices and prior methods of irradiating products using product irradiation devices.




Another object of the present invention is to move products relative to and along a non-moving transport surface within a product irradiation device such that the products are moved past an irradiation source within the product irradiation device.




A further object of the present invention is to utilize only a minimal number of hydraulic actuators to move products in a prescribed path through a product irradiation device.




An additional object of the present invention is to eliminate the presence of moving mechanical parts in a high radiation zone of a product irradiation device.




Yet another object of the present invention is to prevent intermingling or mixing of non-irradiated products entering a product irradiation device and irradiated products exiting the product irradiation device.




It is also an object of the present invention to introduce products to be irradiated into a product irradiation device through an entry opening of the product irradiation device and to discharge irradiated products from the product irradiation device through an exit opening of the product irradiation device, the exit opening being disposed at a location remote from the entry opening.




The present invention has as a further object to introduce products into a product irradiation device, to move the products through the product irradiation device and to discharge the products from the product irradiation device with a maximum external dimension of the products disposed parallel to a plane of an irradiation source within the product irradiation device.




Some of the advantages of the present invention are that personnel requirements for operation and/or maintenance of the product irradiation device are minimized, the product irradiation device does not require any on-site fabrication at the source of the products to be irradiated, standard, transportable enclosures may be used for the product irradiation device, no foundation work is required for the enclosure at the source of the products, no lubricants are present in the high radiation zone, the product irradiation device is entirely self-contained, the product irradiation device is capable of automatic operation with high radiation efficiency, products may be irradiated at their manufacturing or processing facilities, the product irradiation device is relatively small and light weight, the product irradiation device is transportable, products can be irradiated with or without the products being placed in special bins or containers for movement through the irradiation device, mechanical malfunctions are reduced or eliminated, suspensions in normal operation of the product irradiation device are reduced, human access to the interior of the product irradiation device is restricted, redundant interlocks and/or opening/closing mechanisms to prevent human access are not needed, all products receive the same total exposure to radiation, the product irradiation device may be provided with auxiliary equipment for lighting, cooling and/or heating, the auxiliary equipment does not require any supply, such as power, from the source of the products, no personnel are required within the processing facility to handle non-irradiated and irradiated products, personnel requirements are limited to monitoring system operations, periodic maintenance and periodic irradiation source replacement, the irradiation source, once installed, is not moved until replacement is necessary due to radioactive decay, and thermal transients associated with moving irradiation sources into and out of water pools are eliminated.




These and other objects, advantages and benefits are realized with the present invention as generally characterized in a product irradiation device including an enclosure and an irradiator shell disposed in the enclosure. The irradiator shell comprises a wall or walls enclosing an irradiation source and a transport channel. The shell has an inlet port communicating with the transport channel and through which products, prior to being irradiated, are introduced in succession into the transport channel. The shell has an outlet port, different from the inlet port, communicating with the transport channel and through which the products, subsequent to being irradiated, are discharged in succession from the transport channel. The shell has a non-moving transport surface defined by an interior surface or surfaces of the wall or walls and upon which the products are moved through the transport channel past the irradiation source, whereby the products are irradiated. The irradiation source is disposed in a plane, and the transport surface is disposed in a plane perpendicular to the plane of the source. A plurality of hydraulic actuators are provided in or on the shell for moving the products into, through and out of the transport channel in fixed increments with an external dimension of the products parallel to the plane of the source. The enclosure has an entry opening communicating with the inlet port and through which the products are introduced in the transport channel, via the inlet port, from external of the enclosure. The enclosure has an exit opening communicating with the outlet port and through which the products discharged from the transport channel, via the outlet port, are transported to a location external of the enclosure, the exit opening being disposed at a location remote from the entry opening.




A method of irradiating products according to the present invention comprises the steps of introducing products in succession into a transport channel of an irradiator shell via an inlet port of the shell, moving the products relative to and upon a non-moving transport surface of the shell to advance the products through the transport channel in fixed increments such that the products are moved past an irradiation source within the shell and are thereby irradiated, and discharging the products in succession from the transport channel via an outlet port of the shell disposed at a location different from the inlet port.




Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings, wherein like parts in each of the several figures are identified by the same reference characters.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a product irradiation device according to the present invention.





FIG. 2

is a perspective view of an irradiator shell of the product irradiation device.





FIG. 3

is a sectional view of the irradiator shell.





FIG. 4

is a broken perspective view of a rod assembly of an irradiation source within the irradiator shell.





FIG. 5

is a perspective view illustrating one of a plurality of baskets containing products to be irradiated.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




A product irradiation device according to the present invention is illustrated at


10


in FIG.


1


. The product irradiation device


10


includes a transportable or mobile enclosure


12


and an irradiator shell


14


, illustrated in

FIG. 2

, disposed in enclosure


12


. The enclosure


12


includes a top wall or roof


15


, a bottom wall or floor


16


, opposing side walls


17


and


17


′, a forward wall


18


and a rearward wall


19


. In the case of enclosure


12


, the walls


15


,


16


,


17


,


17


′,


18


and


19


are flat or planar with top wall


15


parallel to bottom wall


16


, side walls


17


and


17


′ parallel to one another and forward wall


18


parallel to rearward wall


19


. A plurality of doors


20


are provided on enclosure


12


, the doors


20


being selectively closeable to close the enclosure


12


and being selectively openable to present access openings communicating with the interior of enclosure


12


.




As shown in

FIG. 1

, two pairs of doors


20


are hingedly mounted on side wall


17


with the doors


20


of each pair disposed next to one another or in side by side relation. Accordingly, each pair of doors


20


, when open, presents an access opening on the side wall


17


corresponding or substantially corresponding in size to the height and the combined widths of the doors


20


. The pairs of doors


20


are disposed at spaced locations along side wall


17


such that the access openings presented thereby are also spaced from one another. Another pair of doors


20


defines the rearward wall


19


, the doors of the another pair being hingedly mounted to side walls


17


and


17


′, respectively, at a rearward end of the enclosure


12


as shown in FIG.


1


. When the another pair of doors


20


defining rearward wall


19


are open, an access opening circumscribed by the top, bottom and side walls is presented at the rearward end of the enclosure


12


. At least one additional pair of doors


20


(not visible in

FIG. 1

) is provided on side wall


17


′, the at least one additional pair of doors


20


being aligned with one of the pairs of doors


20


on side wall


17


. In the case of enclosure


12


, the rearwardmost pair of doors


20


on side wall


17


is aligned, in a direction transverse or perpendicular to a longitudinal axis of enclosure


12


, with the at least one additional pair of doors


20


on side wall


17


′. The access opening presented when the rearwardmost pair of doors


20


on side wall


17


′ are open serves as an exit or discharge opening for exit or discharge of irradiated products from the product irradiation device


10


. The access opening presented when the at least one additional pair of doors on side wall


17


are open serves as an entry opening for introduction or entry of non-irradiated products into the product irradiation device


10


. The doors


20


may be mounted on the enclosure


12


singly or in pairs depending on the sizes of the doors and the sizes desired for the access openings. Preferably, at least some of the access openings are of a size to permit human access and the introduction of necessary equipment into the interior of the enclosure. Doors


20


, arranged singly or in pairs, may be provided on any or all walls of the enclosure. The doors


20


may be provided with latches or locks for locking the doors in a closed position, and such latches or locks may be conventional. Although the doors are disclosed herein as being hingedly mounted on the enclosure, it should be appreciated that the doors can be mounted on the enclosure in various other ways, such as being slidably mounted on the enclosure.




The enclosure


12


is mounted or supported on a plurality of wheels


22


by which the enclosure


12


can be transported along the ground or other surface. The enclosure


12


is mounted on six sets of wheels


22


as shown in FIG.


1


. Three sets of wheels


22


are disposed adjacent or proximate the rearward end of the enclosure


12


while another three sets of wheels


22


are disposed intermediate the rearward end and a forward end of the enclosure


12


. The three sets of wheels


22


disposed adjacent or proximate the rearward end are rearwardly spaced from the three sets of wheels


22


disposed intermediate the forward and rearward ends. No wheels


22


are provided at, adjacent or proximate the forward end since the forward end of enclosure


12


is adapted to be removably coupled to a powered wheeled vehicle (not shown) by which the enclosure


12


is transported along the ground or other surface. Apparatus and/or structure for coupling the enclosure


12


to a powered wheeled vehicle may be conventional in nature, such as that employed in conventional truck trailer design whereby the forward end of the enclosure


12


is supported upon one or more sets of wheels of the powered wheeled vehicle.




The enclosure


12


is provided with a selectively extendable, selectively retractable rigid brace or support


24


for supporting the forward end of the enclosure when the enclosure is not coupled to the powered wheeled vehicle.

FIG. 1

shows the support


24


, which is located at, adjacent or proximate the forward end of enclosure


12


, extended beneath the bottom wall


16


in a direction perpendicular thereto. When the support


24


is thusly extended, a pair of feet


25


of the support


24


engage the ground or other surface upon which the wheels


22


are disposed, only one foot


25


being visible in FIG.


1


. The support


24


supports the forward end of the enclosure


12


so that the enclosure


12


is in a level, horizontal position and prevents movement of the enclosure


12


upon the ground or other surface. Of course, the enclosure


12


may also be provided with a suitable brake for preventing movement of the enclosure


12


upon the ground or other surfaces. When the support


24


is retracted, the feet


25


do not engage the ground or other surface and movement of the enclosure


12


thereupon via the wheels


22


is permitted.




Preferably, the enclosure


12


is a standard truck trailer, as shown in

FIG. 1

, capable of being coupled to a truck by which the truck trailer is transported. It should be appreciated, however, that other standard enclosures, such as a rail car or a transportable container, may be used for enclosure


12


. The enclosure


12


is capable of being transported or delivered to a loading dock or other suitable location at a manufacturing or processing facility or other source of products to be irradiated with the product irradiation device


10


. Once delivered to the desired location, the enclosure


12


is detached from the truck and is parked, as shown in

FIG. 1

, without requiring any foundation work or other onsite construction or fabrication. The enclosure


12


can be provided with a plurality of braces


24


at various locations along the floor


16


thereof. Accordingly, once the enclosure


12


has been delivered to the desired location, the wheels


22


can be removed therefrom and the enclosure can be supported entirely by the plurality of braces


24


. Of course, the braces


24


should be considered illustrative in that various support structure can be used to support the enclosure, with or without removal of the wheels


22


.




The product irradiation device


10


is entirely self-contained in that all systems needed to operate the product irradiation device, as well as auxiliary equipment therefor, and to accomplish irradiation of products therewith are provided in or on the product irradiation device and do not require any integration with or supply of power from the manufacturing or processing facility or other source of the products to be irradiated. Equipment for various purposes, such as electricity generation, refrigeration, heating, ventilation and/or cooling (HVAC) and any other necessary or optional service, and the systems for operating such equipment, are provided in or on the enclosure


12


.

FIG. 1

illustrates enclosure


12


provided with a generator module


26


and an HVAC module


28


, both of which are mounted or supported on the top wall


15


of the enclosure


12


. The generator module


26


is used to generate electricity for various purposes, while the HVAC module


28


is used for heating, ventilation and/or cooling of the shell


14


and/or the enclosure


12


as well as for removing heat from an irradiation source disposed in shell


14


as explained further below. The HVAC module


28


can include a suitable compressor or other equipment capable of refrigerating the interior of the shell


14


and/or the interior of enclosure


12


where the products to be irradiated require refrigeration, as in the case of frozen products.




The irradiator shell


14


is disposed entirely within the interior of enclosure


12


. The external size of irradiator shell


14


is smaller in size than the interior of enclosure


12


, and the portion of the interior of enclosure


12


not occupied by irradiator shell


14


is used to accommodate equipment necessary or useful for operation of the product irradiation device


10


. In the case of product irradiation device


10


, the irradiator shell


14


has an external configuration and size to fit within the interior of a standard truck trailer, i.e. enclosure


12


. The irradiator shell


14


is shielded to minimize or prevent exposure of operating personnel, the public and the environment to ionizing radiation. Accordingly, it is preferred that the irradiator shell


14


be at least partly made of radiation impenetrable or absorbable material, such as steel or lead, forming a wall or walls enclosing an irradiation source and a product transport channel circumscribed or defined by an interior surface or surfaces of the wall or walls of the irradiator shell. The interior surface or surfaces defining the product transport channel are preferably made of stainless steel, as are exterior or visible surfaces of the shell


14


, while the bulk of the shell


14


is made of less costly carbon steel or lead. The irradiator shell


14


has a generally T-shaped external configuration with a longitudinal shell section


30


and a transverse shell section


32


joined to and extending perpendicularly to the longitudinal shell section


30


. Preferably, the longitudinal and transverse shell sections each have a square or rectangular external cross-sectional configuration, although other external cross-sectional configurations are possible. As shown in

FIG. 2

, the longitudinal shell section


30


has a square external cross-sectional configuration, and the transverse shell section has a rectangular external cross-sectional configuration.




The longitudinal shell section


30


is defined by a planar upperwall


34


, a planar lower wall


35


parallel to upper wall


34


, a pair of planar, parallel side walls


36


and


36


′ extending between upper wall


34


and lower wall


35


and a planar end wall


37


. The transverse shell section


32


is defined by the planar upper wall


34


, the planar lower wall


35


, a planar side wall


38


extending between upper wall


34


and lower wall


35


, a pair of planar side wall segments


39


and


39


′ parallel to side wall


38


and a pair of planar end walls


40


and


40


′. The side wall segments


39


and


39


′, one of which is disposed on each side of the longitudinal shell section


30


, extend between upper wall


34


and lower wall


35


and also extend between side walls


36


and


36


′ and end walls


40


and


40


′, respectively. The end wall


37


is parallel to the side wall


38


and the side wall segments


39


and


39


′. The side walls


36


and


36


′ are parallel to the end walls


40


and


40


′.




As best shown in

FIG. 3

, a product transport passage or channel


41


is defined within the irradiator shell


14


and is made up of inner longitudinal channel sections


42


and


42


′, outer transverse channel sections


43


and


43


′ disposed at first ends of the inner longitudinal channel sections


42


and


42


′, respectively, an inner transverse channel section


44


disposed at opposite or second ends of the inner longitudinal channel sections


42


and


42


′, respectively, and outer longitudinal channel sections


45


and


45


′ disposed at outer ends of the outer transverse channel sections


43


and


43


′, respectively. The outer longitudinal channel sections


45


and


45


′ extend from the outer ends of the outer transverse channel sections


43


and


43


′, respectively, to openings or ports


46


and


46


′, respectively, in the transverse shell section


32


. The openings or ports


46


and


46


′ are disposed on planar exterior surfaces of side wall segments


39


and


39


′, respectively, and establish communication with the product transport channel


41


from externally of the shell


14


. The openings or ports


46


and


46


′ are disposed adjacent planar exterior surfaces of the side walls


36


and


36


′, respectively.




The inner longitudinal channel sections


42


and


42


′ are parallel to one another and extend longitudinally in the longitudinal shell section


30


and part way into the transverse shell section


32


. The outer transverse channel sections


43


and


43


′, which are disposed within the transverse shell section


32


, are perpendicular to the inner longitudinal channel sections


42


and


42


′ and the outer longitudinal channel sections


45


and


45


′. The outer transverse channel sections


43


and


43


′ have inner ends communicating with the first ends of the inner longitudinal channel sections


42


and


42


′, respectively, and have the outer ends thereof communicating with the outer longitudinal channel sections


45


and


45


′, respectively. The inner transverse channel section


44


is perpendicular to the inner longitudinal channel sections


42


and


42


′. The inner transverse channel section


44


is disposed in the longitudinal shell section


30


and extends between the opposite or second ends of the inner longitudinal channel sections


42


and


42


′, respectively. The outer longitudinal channel sections


45


and


45


′ are disposed in the transverse shell section


32


and are parallel to the inner longitudinal channel sections


42


and


42


′. The outer longitudinal channel sections


45


and


45


′ extend between the outer ends of the outer transverse channel sections


43


and


43


′, respectively, and the openings or ports


46


and


46


′, respectively.




The product transport channel


41


and the ports


46


and


46


′ have a cross-sectional configuration and size large enough to accommodate and facilitate the passage therethrough of products, such as products


47


shown in

FIGS. 2 and 3

. Preferably, the cross-section of the product transport channel


41


and the ports


46


and


46


′ corresponds as close as possible in size and configuration to the external cross-section of the individual products


47


, or to containers such as bins or baskets holding one or more products, while allowing the products


47


or the containers for the products to freely pass therethrough. The products


47


are moved in a longitudinal direction through the inner and outer longitudinal channel sections


42


,


42


′,


45


and


45


′ and are moved in a transverse direction, perpendicular to the longitudinal direction, through the inner and outer transverse channel sections


43


,


43


′ and


44


. Although the direction of movement for the products


47


through the channel


41


thusly changes, the orientation or position of the products


47


does not change as the products are introduced in, moved through and discharged from channel


41


. When the products


47


are moved in channel


41


in the longitudinal direction, an external dimension D


1


of the products


47


is aligned with the longitudinal direction of movement. When the products


47


are moved in channel


41


in the transverse direction, an external dimension D


2


of the products


47


is aligned with the transverse direction of movement. In the instance of products


47


, the external dimension D


1


is a major or maximum external dimension defining a major axis of the products while the external dimension D


2


is a minor external dimension defining a minor axis of the products.




Where the external dimensions D


1


and D


2


are equal or the same, the channel


41


may be of uniform or constant cross-section from port


46


to port


46


′. Where external dimensions D


1


and D


2


are not the same, as shown for products


47


, the channel


41


can be of non-uniform or non-constant cross-section from port


46


to port


46


′. In particular, longitudinal channel sections


42


,


42


′,


45


and


45


′ can have a cross-section corresponding in size and shape to the cross-section of external dimension D


2


while the transverse channel sections


43


,


43


′ and


44


can have a cross-section corresponding in size and shape to the cross-section of external dimension D


1


. It should be appreciated, therefore, that the cross-section of channel


41


may be uniform and constant or non-uniform and non-constant depending on the cross-sectional dimensions of the products and the direction of movement of the products in the channel


41


.




The cross-section of the channel


41


and the ports


46


and


46


′ is defined or circumscribed by a planar interior surface or surfaces of the wall or walls of the irradiator shell


14


, such interior surface or surfaces preferably being made of stainless steel as described above. The planar interior surface


48


of lower wall


35


is a transport surface


48


upon which the products


47


are directly supported and are moved through the irradiator shell


14


. The transport surface


48


, which is non-moving, may be finished, such as by polishing or other treatment, to minimize friction when the products are moved thereupon. Any or all of the other interior surfaces of the walls of the irradiator shell


14


defining the channel


41


may be finished, such as by polishing or other treatment, to minimize friction and promote passage of the products through the channel


41


. The walls of irradiator shell


14


are of sufficient thickness to prevent the emission of unsafe levels of radiation externally of shell


14


from an irradiation source disposed within the shell


14


.




An irradiation source


49


, shown in

FIG. 3

, is disposed in shell


14


and includes an array of elongate rods


50


made of radioactive material, such as Cobalt 60. Rods


50


extend vertically in shell


14


with their central longitudinal axes, respectively, disposed in a plane P


1


perpendicular to upper and lower walls


34


and


35


. A shield plug


51


is provided above the upper end of each rod


50


, and each rod


50


is disposed in an outer tube or jacket


52


to form a rod assembly as shown in FIG.


4


. Tubes


52


containing rods


50


are disposed close to one another in parallel, side by side relation to be arranged in shell


14


linearly or in series with the central longitudinal axes of rods


50


disposed in the plane P


1


, which contains the central longitudinal axis of longitudinal shell section


30


and is perpendicular to the transport surface


48


and parallel to the side walls


36


and


36


′ and the end walls


40


and


40


′.




Rods


50


, with their outer tubes


52


, are disposed in a shell insert


53


disposed between inner longitudinal channel section


42


and inner longitudinal channel section


42


′. The shell insert


53


has spaced, planar, parallel side faces


54


and


54


′ between which the tubes


52


containing rods


50


are disposed, the side faces


54


and


54


′ being parallel to plane P


1


. The side faces


54


and


54


′ extend vertically in the shell


14


between a planar interior surface of the upper wall


34


and the planar interior surface of the lower wall


35


, i.e. the transport surface


48


. The side faces


54


and


54


′ extend longitudinally in the shell


14


from a planar interior surface of side wall


38


up to the inner transverse channel section


44


, whereat the side faces


54


and


54


′ are joined to one another by a transverse end face


55


. The rods


50


are serially or linearly arranged between the side faces


54


and


54


′ to extend therebetween a linear distance corresponding or substantially corresponding to the linear distance between the end face


55


and a plane P


2


containing planar exterior surfaces of side wall segments


39


and


39


′ as shown in

FIGS. 2 and 3

. The linear distance that the rods


50


occupy within the shell


14


defines an active length for the irradiation source


49


.




The number of and spacing for the rods in shell


14


may vary depending on the radiation strength or intensity of the individual rods


50


, the total or cumulative radiation strength or intensity desired for the source


49


and/or the desired active length. The radiation strength or intensity of the individual rods


50


can vary depending on the number of and spacing for the rods


50


, the total radiation strength or intensity desired for the irradiation source and/or the desired active length. The rods


50


have diameters concentrically received within the tubes


52


, respectively. The perpendicular distance between side faces


54


and


54


′ is sufficient to accommodate the tubes


52


therebetween. The rods


50


and tubes


52


have a length extending perpendicularly between the upperwall


34


and the lower wall


35


, such length being at least as great as the perpendicular distance between the interior surface of upper wall


34


and the interior surface of lower wall


35


, i.e. the transport surface


48


. The shield plugs


51


have a stepped configuration for reception in correspondingly configured openings or holes, respectively, in the upper wall


34


as shown in

FIGS. 2 and 4

. The shield plugs


51


are removably disposed in the upper wall


34


allowing the rods


50


to be removed and/or replaced via withdrawal through the openings or holes in upper wall


34


. In particular, the rods


50


can be individually installed and/or removed at the same time that product irradiation is taking place. The irradiation source, i.e. rods


50


, is not transported with the enclosure


12


or shell


14


. Rather, the enclosure


12


and shell


14


are transported and delivered to the source of the products separately from the irradiation source. It is contemplated that the irradiation source would be purchased from suppliers equipped with licensed transport casks and from whom disposal services would also be obtained.




The shell insert


53


partitions or divides the shell


14


into an inlet or entry side disposed on one side of insert


53


and, therefore, plane P


1


, and an outlet or exit side disposed on the other or opposite side of insert


53


and, therefore, plane P


1


. The side wall segment


39


is disposed on the one side of plane P


1


while the side wall segment


39


′ is disposed on the opposite side of plane P


1


. Accordingly, the port


46


constitutes an inlet or entry port, disposed on the one side of plane P


1


, while the port


46


′ constitutes an outlet or exit port, disposed on the opposite side of plane P


1


, the inlet and outlet ports being disposed in plane P


2


, which is perpendicular to plane P


1


. A prescribed path is defined in shell


14


between the inlet port


46


and the outlet port


46


′ and along which the products


47


are moved through the shell


14


. The prescribed path, which corresponds to the transport channel


41


, begins at the inlet port


46


and includes, in sequence, the outer longitudinal channel section


45


, the outer transverse channel section


43


, the inner longitudinal channel section


42


, the inner transverse channel section


44


, by which the inlet side and the outlet side are in communication, the inner longitudinal channel section


42


′, the outer transverse channel section


43


′ and the outer longitudinal channel section


45


′, the prescribed path terminating at the outlet port


46


′. Hence, the transport surface


48


extends from the inlet port to the outlet port, which is spaced or remote from or disposed at a different location than the inlet port. A portion of the prescribed path is in a high radiation zone of the transport channel


41


, the high radiation zone corresponding to the active length of the irradiation source


49


. Accordingly, the high radiation zone is defined between plane P


2


and the inner transverse channel section


44


and thusly includes the inner longitudinal channel sections


42


and


42


′.




The shell


14


can be introduced in the interior of enclosure


12


via the access opening presented when the doors


20


forming rearward wall


19


are open. The lower wall


35


of shell


14


is supported upon the bottom wall or floor


16


of enclosure


12


. The shell


14


is positioned in the interior of enclosure


12


so that the inlet port


46


and the outlet port


46


′ are aligned with the entry and exit openings, respectively, of the enclosure, the entry and exit openings being presented when the rearwardmost doors


20


on side walls


17


and


17


′, respectively, are open. Subsequent to introduction and proper positioning of shell


14


in the interior of enclosure


12


, the doors


20


forming rearward wall


19


will normally remain closed and locked. The doors


20


defining the entry and exit openings, respectively, will be open during operation of the product irradiation device


10


and will normally be closed and locked when the product irradiation device


10


is not in operation.




Products


47


, prior to being irradiated, are presented at the inlet port


46


via a delivery member


60


extending through the entry opening of enclosure


12


and establishing communication between the inlet port


46


and the source of the products


47


. The delivery member


60


may be supplied as part of the product irradiation device


10


or as a separate component provided by the user of the product irradiation device, in which case the product irradiation device may be supplied without a delivery member. In the case of product irradiation device


10


, the delivery member


60


is supplied as part of the product irradiation device and includes a roller ramp


61


extending through the entry opening of enclosure


12


and having a first end positioned in front of the inlet port


46


, adjacent or in abutment with the planar exterior surface of the side wall


36


, and a second end disposed at or proximate the source of the products


47


.




The first end of the roller ramp


61


is located directly in front of the inlet port


46


so that a product


47


supported on the first end is aligned with the inlet port


46


and is ready to be passed therethrough into the transport channel


41


. The second end of the roller ramp


61


is disposed, externally of enclosure


12


, at a convenient location at the source of the products


47


. For example, the second end of the roller ramp


61


may be disposed at a loading dock or other location of the manufacturing or processing facility for the products


47


. The second end of roller ramp


61


is elevated or disposed higher than the first end thereof so that the products


47


are conveyed by gravity from the second end to the first end. Accordingly, the roller ramp


61


will be disposed at an obtuse angle to the ground or other surface upon which the enclosure


12


is supported. As shown in

FIG. 2

, the first end of the roller ramp


61


may be angled relative to the remainder thereof so that the first end of the roller ramp


61


is disposed in the same or substantially the same plane as the transport surface


48


.




Products


47


positioned upon the second end of the roller ramp


61


are automatically conveyed by gravity from the second end to the first end of the roller ramp


61


, as facilitated by rollers of the roller ramp, the products


47


being guided or directed by upstanding, parallel side rails


62


of the roller ramp


61


. As shown in

FIGS. 2 and 3

, the perpendicular distance between side rails


62


corresponds to the external dimension D


1


of the products


47


. The products


47


are conveyed along the delivery member


60


in a transverse direction perpendicular to plane P


1


with the minor axis or external dimension D


2


of the products


47


longitudinally or axially aligned with the transverse direction of conveyance of the products along the delivery member and with the major axis or external dimension D


1


of the products parallel with plane P


1


. Accordingly, products are presented at the first end of the delivery member with the major axis longitudinally or axially aligned with inlet port


46


and outer longitudinal channel section


45


. The exterior surface of side wall


36


serves as a stop or abutment for the products


47


at the first end of the delivery member


60


and facilitates alignment of the products


47


with the inlet port


46


and with the outer longitudinal channel section


45


.




Products


47


, subsequent to being irradiated, exit the shell


14


through the outlet port


46


′ and are discharged onto a discharge member


64


extending through the exit opening of enclosure


12


. The discharge member


64


may be supplied as part of the product irradiation device


10


or as a separate component provided by the user, in which case the product irradiation device can be supplied without a discharge member. In the case of product irradiation device


10


, the discharge member


64


is supplied as part of the product irradiation device and includes a roller ramp


65


, similar to the roller ramp


61


. The roller ramp


65


extends through the exit opening of enclosure


12


and has a first end positioned in front of the outlet port


46


′, adjacent or in abutment with a planar exterior surface of the side wall


36


′, and a second end disposed at or proximate the source of the products


47


.




As shown in

FIGS. 2 and 3

, the first end of the roller ramp


65


is located directly in front of the outlet port


46


′ so that a product


47


discharged through the outlet port


46


′ is delivered onto the first end of the roller ramp


65


. The second end of the roller ramp


65


is disposed, externally of enclosure


12


, at a convenient location at the source of the products


47


. For example, the second end of the roller ramp


65


may be disposed at another loading dock or location of the manufacturing or processing facility for the products


47


. The second end of roller ramp


65


is disposed lower than the first end thereof so that the products


47


are conveyed by gravity from the first end to the second thereof. Accordingly, the roller ramp


65


will be disposed at an acute angle to the ground or surface upon which the enclosure


12


is supported. As shown in

FIG. 2

, the first end of the roller ramp


65


may be angled relative to the remainder thereof so that the first end of the roller ramp


65


is disposed in the same or substantially the same plane as the transport surface


48


.




Products


47


discharged through the outlet port


46


′ onto the first end of roller ramp


65


are automatically conveyed from the first end to the second end thereof as facilitated by rollers of the roller ramp


65


, and the products


47


are guided by upstanding, parallel side rails


62


of the roller ramp


65


. The products


47


are discharged from the outlet port


46


′ with their major axis or external dimension D


1


parallel to plane P


1


. The products


47


are conveyed along the discharge member


64


in a transverse direction perpendicular to plane P


1


with the minor axis or external dimension D


2


of the products


47


longitudinally or axially aligned with the transverse direction of conveyance of the products along the discharge member and with the major axis or external dimension D


1


parallel with plane P


1


.




It should be appreciated that the delivery member, the discharge member, the shell and/or the enclosure may be provided with a mechanism or mechanisms for securing the first ends of the delivery member and the discharge member, respectively, adjacent the inlet port and the outlet port, respectively. It should be further appreciated that the mechanism or mechanisms used to secure the first ends of the delivery member and/or the discharge member, respectively, adjacent the inlet port and outlet port, respectively, can be designed to allow the delivery member and/or discharge member to be detached or released from the shell and/or the enclosure. Accordingly, the delivery member and/or the discharge member can be detached or removed from the enclosure and/or the shell when the product irradiation device is not in use. The delivery member and/or the discharge member can be designed for movement between a deployed position, wherein the delivery member and/or the discharge member extends externally from the enclosure, and a nondeployed position, wherein the delivery member and/or the discharge member is disposed within the enclosure. For example, the delivery member and/or the discharge member may be pivotably, hingedly or rotatably mounted to the enclosure and/or the shell so that the delivery member and/or the discharge member may be pivotably, rotatably or hingedly moved into the enclosure to assume the non-deployed position and may be pivotably, hingedly or rotatably moved out from the enclosure to assume the deployed position. It should also be appreciated that the angular orientations of the delivery member and the discharge member, respectively, including the first ends thereof, can be selected, adjusted or varied in accordance with the conveying speed desired for the products therealong.




A plurality of hydraulic or pneumatic actuators


66


are provided in or on the product irradiation device


10


for moving or advancing the products


47


incrementally into, through and out of the shell


14


in the prescribed path. The actuators


66


serve to push and/or pull the products


47


, in fixed increments, into, through and out of the shell


14


, and each includes a hydraulic or pneumatic cylinder


68


and a piston


70


slidably disposed in the cylinder


68


. Seven actuators


66




a,




66




b,




66




c,




66




d,




66




e,




66




f


and


66




g


are provided for product irradiation device


10


as best shown in FIG.


3


.




The actuator


66




a


serves to push a product


47


disposed at the first end of the delivery member


60


through the inlet port


46


and into the outer longitudinal channel section


45


. The actuator


66




a


is disposed externally of shell


14


in its entirety with its cylinder


68




a


and piston


70




a


longitudinally or axially aligned with the inlet port


46


and the outer longitudinal channel section


45


. As shown in

FIGS. 2 and 3

, the cylinder


68




a


is secured to or mounted on the exterior surface of side wall


36


via a mounting block secured to the side wall


36


. The piston


70




a,


which has a longitudinal axis parallel with plane P


1


and perpendicular to plane P


2


, is longitudinally, slidably movable within the cylinder


68


a in response to variation in fluidic pressure within the cylinder


68




a.


The piston


70




a


is slidably movable relative to cylinder


68




a


between a retracted position wherein a product engaging end


74




a


of the piston


68




a


is disposed adjacent, close to or in abutment with the cylinder


68




a


and an extended position wherein the product engaging end


74




a


is disposed further away from the cylinder


68




a


and, in particular, is adjacent or aligned with the plane P


2


and, therefore, with the inlet port


46


as shown in dotted lines in FIG.


3


.




In the retracted position for piston


70




a,


the product engaging end


74




a


is spaced from the plane P


2


, and the distance that the end


74




a


is spaced from plane P


2


, i.e. the stroke of piston


70




a,


is at least as large as the external dimension D


1


of the products


47


. A product


47


, when disposed at the first end of the delivery member


60


, thusly has its external dimension D


1


disposed between the inlet port


46


and the product engaging end


74




a


when the piston


70




a


is in the retracted position. In this manner, the major or maximum external dimension D


1


will be disposed parallel to plane P


1


and perpendicular to plane P


2


when the product


47


is disposed at the first end of the delivery member


60


between the inlet port


46


and the product engaging end


74




a.






The product engaging end


74




a


engages the product


47


disposed at the first end of the delivery member


60


as the piston


70




a


is moved from the retracted position to the extended position. The product engaging end


74




a


engages the product from behind, such that a pushing force is applied to a rearward end


80


′ of the product in the direction of its major axis. The product engaging end


74




a


can be formed as or provided with structure or a surface having a size and configuration to facilitate application of the pushing force on the product


47


as the piston


70




a


is moved toward the extended position. In the case of piston


70




a,


the product engaging end


74




a


is formed as a plate having a flat or planar surface for contacting or engaging a flat or planar surface of the product


47


. When the piston


70




a


is in the extended position, as shown in dotted lines in

FIG. 3

, the product


47


pushed thereby will have passed through the inlet port


46


and will be disposed in the outer longitudinal channel section


45


. When the piston


70




a


is thereafter moved from the extended position to the retracted position, a next subsequent product


47


is automatically presented, due to gravity, at the first end of the delivery member


60


and is ready to be pushed by the piston


70




a


through the inlet port


46


and into the outer longitudinal channel section


45


in response to movement of the piston


70




a


from the retracted position to the extended position.




Movement of the next subsequent product


47


through the inlet port


46


and into the outer longitudinal channel section


45


by the piston


70




a


causes the next subsequent product to engage, in end to end relation, the next preceding product, i.e. the product


47


previously moved into the outer longitudinal channel section


45


by the piston


70




a.


Accordingly, each time the piston


70




a


is moved from the retracted position to the extended position, a product


47


disposed at the first end of the delivery member


60


is moved through the inlet port


46


into the outer longitudinal channel section


45


, causing corresponding movement of all preceding products in the outer longitudinal channel section


45


due to end to end contact or abutment between the products. In this manner, the product at the first end of the delivery member and preceding products in the outer longitudinal channel section


45


are each moved or advanced a single position or increment corresponding to external dimension D


1


. The products


47


moved by actuator


66




a


are moved in a longitudinal direction parallel to plane P


1


with the major axis or external dimension D


1


disposed parallel to plane P


1


and in longitudinal or axial alignment with the longitudinal direction of movement. Each time the piston


70




a


is moved from the extended position to the retracted position, another product is presented at the first end of the delivery member


60


in alignment with the actuator


66




a


and the inlet port


46


.




In the case of product irradiation device


10


, the outer longitudinal channel section


45


has a length, parallel to plane P


1


, corresponding to external dimension D


1


. Accordingly, only one product


47


can be disposed entirely within the outer longitudinal channel section


45


at a time. A product


47


disposed entirely in the outer longitudinal channel section


45


will be pushed, moved or advanced by a next subsequent product, acted upon by the piston


70




a,


into the outer end of the outer transverse channel section


43


, which is aligned and continuous with the outer longitudinal channel section


45


. As shown in dotted lines in

FIG. 3

, a product moved into the outer end of the outer transverse channel section


43


is in end to end contact or abutment with the next subsequent product disposed in the outer longitudinal channel section


45


. It should be appreciated that the length of the outer longitudinal channel section can be increased to accommodate more than one product.




The actuator


66




b


serves to push a product located at the outer end of the outer transverse channel section


43


such that the product and all preceding products disposed in the outer transverse channel section


43


is/are advanced or moved a single position or increment. The actuator


66




b


is similar to actuator


66




a


and has its cylinder


68


b and piston


70




b


longitudinally or axially aligned with the outer transverse channel section


43


. As shown in

FIG. 3

, the cylinder


68




b


is secured within, on or to the end wall


40


externally of channel


41


, with a longitudinal axis of piston


70




b


perpendicular to plane P


1


and parallel to plane P


2


. When the piston


70




b


of actuator


66




b


is in the retracted position, the product engaging end


74




b


thereof is aligned or flush with or is disposed within a recess of the interior surface of end wall


40


. Accordingly, a product


47


is capable of being moved, in response to actuation of actuator


66




a,


from the outer longitudinal channel section


45


into the outer end of the outer transverse channel section


43


as described above. The thusly moved product


47


will have its major axis or external dimension D


1


longitudinally aligned with the outer longitudinal channel section


45


and will also have its minor axis or external dimension D


2


longitudinally or axially aligned with the outer transverse channel section


43


.




When the piston


70




b


is thereafter moved from the retracted position to the extended position, the product disposed at the outer end of the outer transverse channel section


43


is engaged, from behind, by the product engaging end


74




b,


such that a pushing force is applied to an outer side


78


of the product in the direction of its minor axis. The product


47


disposed at the outer end of the outer transverse channel section


43


is thusly pushed, moved or advanced one position or increment, the product being moved in a transverse direction perpendicular to plane P


1


while its major axis or external dimension D


1


remains parallel to plane P


1


. When the piston


70




b


is thereafter moved from the extended position to the retracted position, a next subsequent product


47


is able to be moved into the outer end of the outer transverse channel section


43


in response to actuation of actuator


66




a.


When the piston


70




b


is moved to the extended position after a subsequent product


47


has been moved into the outer end of the outer transverse channel section


43


, the piston


70




b


moves the subsequent product


47


, which engages the outer side


78


of the next preceding product


47


, in the transverse direction. Accordingly, the product at the outer end of the outer transverse channel section


43


as well as preceding products in the outer transverse channel section


43


are each advanced a single position or increment.




In the case of product irradiation device


10


, the outer transverse channel section


43


has a length, between the planar interior surface of end wall


40


and the side face


54


, slightly greater than three times the external dimension D


2


. Accordingly, there is a gap or space


76


between a product at the outer end of the outer transverse channel section


43


and a next preceding product within the outer transverse channel section


43


. The distance that the product engaging end


74




b


is extended perpendicularly beyond the interior surface of end wall


40


when the piston


70




b


is in the extended position defines the stroke for piston


70




b


and corresponds to the external dimension D


2


plus the width of the gap or space


76


. In this manner, a product at the outer end of outer transverse channel section


43


is advanced by piston


70




b


a single position or increment corresponding to the external dimension D


2


plus the width of gap


76


while the next preceding product within the outer transverse channel section


43


is advanced, due to side to side contact or abutment between the products, a single position or increment corresponding to the external dimension D


2


. Subsequent to being so advanced, the next preceding product is disposed at an inner end of the outer transverse channel section


43


, as shown in dotted lines in

FIG. 3

, with its major axis or external dimension D


1


longitudinally or axially aligned with the inner longitudinal channel section


42


, the inner end of the outer transverse channel section


43


being longitudinally aligned and continuous with the inner longitudinal channel section


42


. The products


47


are moved, via actuation of actuator


66




b,


in the transverse direction perpendicular to plane P


1


with the minor axis or external dimension D


2


longitudinally or axially aligned with the transverse direction of movement.




The actuator


66




c


serves to push a product


47


at the inner end of the outer transverse channel section


43


into the inner longitudinal channel section


42


. The actuator


66




c


is similar to actuators


66




a


and


66




b


and has its cylinder


68




c


and piston


70




c


longitudinally or axially aligned with the inner longitudinal channel section


42


. The cylinder


68




c


is secured within, on or to the side wall


38


externally of channel


41


with a longitudinal axis of piston


70




c


parallel to plane P


1


. When the piston


70




c


is in the retracted position, the product engaging end


74




c


thereof is aligned or flush with or disposed within a recess in the interior surface of side wall


38


such that a product


47


is capable of being moved, in response to actuation of actuator


66




b,


into the inner end of outer transverse channel section


43


as described above.




When the piston


70




c


is thereafter moved from the retracted position to the extended position, the product


47


disposed at the inner end of the outer transverse channel section


43


is engaged, from behind, by the product engaging end


74




c,


which applies a pushing force against a forward end


80


of the product in the direction of its major axis, and is moved in a longitudinal direction parallel to plane P


1


into the inner longitudinal channel section


42


as shown in dotted lines in FIG.


3


. The product


47


at the inner end of the transverse channel section


42


is thusly moved or advanced a single position or increment while its major axis or external dimension D


1


remains parallel to plane P


1


. Thereafter, when the piston


70




c


is moved from the extended position to the retracted position, a next subsequent product


47


is able to be moved into the inner end of the outer transverse channel section


43


. When the piston


70




c


is moved from the retracted position to the extended position after a subsequent product


47


has been moved into the inner end of the outer transverse channel section


43


, the subsequent product as well as preceding products in the inner longitudinal channel section


42


are each advanced, due to end to end contact or abutment of the products, a single position or increment corresponding to the external dimension D


1


. When a sufficient number of products


47


are disposed in the inner longitudinal channel section


42


, operation of actuator


66




c


causes a most preceding product


47


in the inner longitudinal channel section


42


to be moved into an outer end of the inner transverse channel section


44


as shown in dotted lines in

FIG. 3

, the outer end of the inner transverse channel section


44


being longitudinally aligned and continuous with the inner, longitudinal channel section


42


.




The products


47


are moved, via actuation of actuator


66




c,


in the longitudinal direction with the major axis or external dimension D l thereof longitudinally or axially aligned with the longitudinal direction of movement. Since the pushing force of piston


70




c


is applied to forward ends


80


of the products while the pushing force of piston


70




a


is applied to rearward ends


80


′ of the products, the longitudinal direction of movement for products advanced by actuator


66




a


is opposite the longitudinal direction of movement for products advanced by actuator


66




c.






In the case of product irradiation device


10


, the distance that product engaging end


74




c


is extended perpendicularly beyond the interior surface of side wall


38


when the piston


70




c


is in the extended position defines the stroke for piston


70




c


and corresponds to the external dimension D


1


. Accordingly, when piston


70




c


moves a product at the inner end of outer transverse channel section


43


, the product and all preceding products disposed in the inner longitudinal channel section


42


are each advanced a single position or increment corresponding to the external dimension D


1


. The inner longitudinal channel section


42


has a length between the inner end of outer transverse channel section


43


and the outer end of inner transverse channel section


44


corresponding to the combined external dimensions D


1


of six products


47


. Therefore, six products


47


are disposed in the inner longitudinal channel section


42


during normal operation of the product irradiation device


10


with such products in contact or abutment with one another in end to end relation. In addition, the most preceding product in inner longitudinal channel section


42


contacts or abuts the product, shown in dotted lines in

FIG. 3

, at the outer end of the inner transverse channel section


44


in end to end relation, and the most subsequent product in the inner longitudinal channel section


42


contacts or abuts the product, shown in dotted lines in

FIG. 3

, at the inner end of the outer transverse channel section


43


in end to end relation. Of course, the length of inner longitudinal channel section


42


can be increased or decreased to accommodate more or fewer products therein.




The actuator


66




d


serves to push a product at the outer end of the inner transverse channel section


44


so as to advance the product in the inner transverse channel section


44


a single position or increment. The actuator


66




d


is similar to actuators


66




a,




66




b


and


66




c.


Actuator


66




d


has its cylinder


68




d


and piston


70




d


longitudinally or axially aligned with the inner transverse channel section


43


. The cylinder


68




d


is secured within, on or to the side wall


36


, externally of channel


41


, with a longitudinal axis of piston


70




d


perpendicular to plane P


1


. When the piston


70




d


is in the retracted position, the product engaging end


74




d


thereof is aligned or flush with or is disposed within a recess in the interior surface of side wall


36


. Accordingly, a product


47


is capable of being moved, in response to actuation of actuator


66




c,


from the inner longitudinal channel section


42


into the outer end of the inner transverse channel section


44


as described above. The thusly moved product will have its major axis or external dimension longitudinally or axially aligned with the inner longitudinal channel section


42


and will have its minor axis or external dimension D


2


longitudinally or axially aligned with the inner transverse channel section


44


, with its major axis or external dimension D


1


remaining parallel to plane P


1


.




When the piston


70




d


is thereafter moved from the retracted position to the extended position, the product


47


disposed at the outer end of inner transverse channel section


44


is engaged, from behind, by product engaging end


74




d


such that a pushing force is applied to the outer side


78


of the product in the direction of its minor axis. The product disposed at the outer end of inner transverse channel section


44


is thusly moved or advanced a single position or increment in the transverse direction perpendicular to plane P


1


. When the piston


70




d


is moved back to the retracted position, a next subsequent product


47


is able to be moved from the inner longitudinal channel section


42


into the outer end of transverse channel section


44


in response to actuation of actuator


66




c.


When the piston


70




d


is moved to the extended position after a subsequent product has been moved into the outer end of the inner transverse channel section


44


, the subsequent product is advanced in the inner transverse channel section


44


. Products


47


are moved, via actuation of actuator


66




d,


in the transverse direction perpendicular to plane P


1


with the minor axis or external dimension D


2


longitudinally or axially aligned with the transverse direction of movement and the major axis or external dimension D


1


parallel to plane P


1


. The transverse direction of movement for products advanced by actuator


66




d


is in the same direction as the transverse direction of movement for products advanced by actuator


66




b.






In the case of product irradiation device


10


, the inner transverse channel section


44


has a length defined between interior surfaces of side walls


36


and


36


′, respectively, and the length of inner transverse channel section


44


is greater than the combined external dimensions D


2


of two products


47


. Accordingly, the distance that the product engaging end


74




d


of piston


70




d


is extended perpendicularly beyond the interior surface of side wall


36


, when the piston


70




d


is in the extended position, defines the stroke of piston


70




d


and is greater than the external dimension D


2


. In particular, the stroke of piston


70




d


is equal to the length of the inner transverse channel section


44


minus the external dimension D


2


. In this manner, a product


47


is moved by piston


70




d


from the outer end of inner transverse channel section


44


to the opposite, outer end of inner transverse channel section


44


in a single stroke, the opposite, outer end of the inner transverse channel section


44


being longitudinally aligned and continuous with the inner longitudinal channel section


42


′. Accordingly, the product


47


moved by piston


70




d


does not advance any preceding products in the inner transverse channel section


44


since no preceding products can be accommodated in inner transverse channel section


44


. Since the product moved by piston


70




d,


in a single stroke, is moved from the outer end of the inner transverse channel section


44


to the opposite, outer end of the inner transverse channel section


44


, such product is moved from the inlet side to the outlet side of the shell


14


.




The actuator


66




e


serves to push the product


47


disposed at the opposite, outer end of the inner transverse channel section


44


into the inner longitudinal channel section


42


′ such that it and preceding products disposed in the inner longitudinal channel section


42


′ is/are advanced a single position. The actuator


66




e


is similar to actuators


66




a,




66




b,




66




c


and


66




d


and has its cylinder


68




e


and piston


70




e


longitudinally or axially aligned with the inner longitudinal channel section


42


′. The cylinder


68




e


is secured in, on or to the end wall


37


, externally of channel


41


, with a longitudinal axis of piston


70




e


parallel to plane P


1


. When the piston


70




e


is in the retracted position, the product engaging end


74


e thereof is aligned or flush with or disposed within a recess in the interior surface of end wall


37


such that a product


47


is capable of being moved, in response to actuation of actuator


66




d,


from the outer end of inner transverse channel section


44


to the opposite, outer end of the inner transverse channel section


44


as described above. The thusly moved product


47


will have its major axis or external dimension D


1


longitudinally or axially aligned with the inner longitudinal channel section


42


′ and, therefore, parallel to plane P


1


.




When the piston


70




e


is thereafter moved from the retracted position to the extended position, the product


47


disposed at the opposite, outer end of inner transverse channel section


44


is engaged, from behind, by the product engaging end


74




e,


which applies a pushing force against the rearward end


80


′ of the product in the direction of its major axis. As shown in dotted lines in

FIG. 3

, the product disposed at the outer end of inner transverse channel section


44


is moved in the longitudinal direction, parallel to plane P


1


, into the inner longitudinal channel section


42


′ and is advanced a single position or increment while its major axis or external dimension D


1


remains parallel to plane P


1


. Thereafter, when the piston


70




e


is moved back to the retracted position, a subsequent product


47


is able to be moved into the opposite, outer end of the inner transverse channel section


44


via actuator


66




d.


When the piston


70




e


is moved from the retracted position to the extended position after a subsequent product has been moved into the opposite, outer end of inner transverse channel section


44


, the subsequent product as well as preceding products in the inner longitudinal channel section


42


′ are each advanced a single position or increment, corresponding to the external dimension D l, due to end to end abutment or contact between the products in the inner longitudinal channel section


42


′.




When a sufficient number of products are disposed in the inner longitudinal channel section


42


′, operation of actuator


66




e


causes a most preceding product in the inner longitudinal channel section


42


′ to be moved into an inner end of the outer transverse channel section


43


′, the inner end of the outer transverse channel section


43


′ being longitudinally aligned and continuous with the inner longitudinal channel section


42


′. Products


47


are moved, via actuation of actuator


66




e,


in the longitudinal direction with the major axis or external dimension D


1


longitudinally or axially aligned with the longitudinal direction of movement. The longitudinal direction of movement for products advanced by actuator


66




e


is in the same direction as the longitudinal direction of movement for products advanced by actuator


66




a,


which is opposite the longitudinal direction of movement for products advanced by actuator


66




c.






In the case of product irradiation device


10


, the distance that the product engaging end


74




e


is disposed beyond the interior surface of end wall


37


when the piston


70




e


is in the extended position defines the stroke for piston


70




e


and is equal to external dimension D


1


. The length of inner longitudinal channel section


42


′ is the same as the length of inner longitudinal channel section


42


such that six products


47


are accommodated in the inner longitudinal channel section


42


′ in end to end contact or abutment. The most subsequent product in the inner longitudinal channel section


42


′ is in end to end contact or abutment with the product at the opposite, outer end of inner transverse channel section


44


as shown in dotted lines in FIG.


3


. The most preceding product in the inner longitudinal channel section


42


′ is in end to end contact or abutment with the product at the inner end of the outer transverse channel section


43


′. Of course, the length of the inner longitudinal channel section


42


′ can be modified in order to accommodate a greater or fewer number of products therein, and the length of the inner longitudinal channel section


42


′ does not have to be the same as the length of inner longitudinal channel section


42


so that different numbers of products can be accommodated therein.




The actuator


66




f


serves to pull a product


47


at the inner end of outer transverse channel section


43


′ to advance the product a single position or increment in the outer transverse channel section


43


′. The actuator


66




f


has a cylinder


68


f mounted in, on or to the end wall


40


′, externally of channel


41


, and a piston


70




f


slidably disposed in the cylinder


68




f


for movement between extended and retracted positions in response to variation in fluidic pressure in the cylinder


68




f.


The cylinder


68




f


and piston


70




f


are aligned with the outer transverse channel section


43


′ with a longitudinal axis of piston


70




f


perpendicular to plane P


1


such that the piston


70




f


is slidable within a space between an upper side of the product or products


47


in outer transverse channel section


43


′ and the top wall


34


of shell


14


or within a recess formed in the top wall


34


of shell


14


. The piston


70




f


has a product engaging end


74




f


depending therefrom and disposed in abutment with the side face


54


′ or within a recess of side face


54


′ in the extended position so as not to block or obstruct movement of a product, in response to actuation of actuator


66




e,


from the inner longitudinal channel section


42


′ into the inner end of the outer transverse channel section


43


′. The product engaging end


74




f


is formed as a flat plate or is otherwise configured to engage the product disposed at the inner end of outer transverse channel section


43


′.




In the extended position for piston


70




f,


the product engaging end


74




f


is in a position to engage the outer side


78


of the product at the inner end of the outer transverse channel section


43


′, and such product will be disposed between the end


74




f


and the interior surface of end wall


40


′. The product engaging end


74




f


engages the outer side


78


of the product at the inner end of outer transverse channel section


43


′ such that a pushing force is applied to the outer side


78


of the product in the direction of its minor axis when the piston


70




f


is moved to the retracted position. The product at the inner end of outer transverse channel section


43


′ is moved by piston


70




f


in a transverse direction, perpendicular to plane P


1


, toward the outer end of the outer transverse channel section


43


′. As the product at the inner end of outer transverse channel section


43


′ is moved by piston


70




f,


a preceding product or products


47


in outer transverse channel section


43


′ is/are moved or advanced in the outer transverse channel section


43


′ due to side to side contact or abutment between the products. The products


47


are moved, in response to actuation of actuator


66




f,


in the transverse direction with the minor axis or external dimension D


2


longitudinally or axially aligned with the transverse direction of movement and with the major axis or external dimension D


1


parallel to plane P


1


. The transverse direction of movement for the products advanced by actuator


66




f


is in the same direction as the transverse direction of movement for products advanced by actuators


66




b


and


66




d.






In the case of product irradiation device


10


, the outer transverse channel section


43


′ has a length between side face


54


′ and the interior surface of end wall


40


′, and the length of the outer transverse channel section


43


′ is the same or substantially the same as the length of outer transverse channel section


43


. When the product


47


at the inner end of outer transverse channel section


43


′ is pulled by piston


70




f,


a single next preceding product is moved, in response thereto, into the outer end of the outer transverse channel section


44


′ as shown in dotted lines in

FIG. 3

, the outer end of the outer transverse channel section


43


′ being longitudinally aligned and continuous with the outer longitudinal channel section


42


′. There is a gap or space


77


between the product


47


disposed at the inner end of the transverse channel section


43


′ and the next preceding product in the outer transverse channel section


43


′. Depending on the design of actuator


66




f,


the stroke of piston


70




f,


i.e. the distance that the piston


70




f


moves between the extended and retracted positions, may correspond or substantially correspond to the external dimension D


2


plus the width of the gap or space


77


, which is the case for actuator


66




f.


Accordingly, in the retracted position, the product engaging end


74




f


will have moved from the extended position a distance equivalent or substantially equivalent to the dimension D


2


plus the width of gap


77


. It should be appreciated that the piston


70




f


does not have to extend into the outer transverse channel section


43


′ in the extended position or in the retracted position such as, for example, when the piston


70




f


is slidably disposed in a passageway or recess formed in the interior surface of upper wall


34


with only the end


74




f


protruding into the outer transverse channel section


43


′.




When the piston


70




f


is moved from the extended position to the retracted position, the product at the inner end of the outer transverse channel section


43


′ is pulled thereby. The next preceding product in the outer transverse channel section has its outer side


78


spaced, by the width of gap


77


, from the inner side


78


′ of the product disposed at the inner end of the outer transverse channel section


43


′. As the product at the inner end of the outer transverse channel section


43


′ is pulled by piston


70




f,


the inner side


78


′ thereof engages the outer side


78


of the next preceding product such that the next preceding product is advanced therewith. Accordingly, products in outer transverse channel section


43


′ are moved or advanced by actuator


66




f


a single position or increment corresponding or substantially corresponding to the external dimension D


2


plus the width of gap


77


. The next preceding product is thusly moved into the outer end of the outer transverse channel section


43


′ as shown in dotted lines in

FIG. 3

, and the product pulled by end


74




f


becomes a next preceding product for the next product to be moved from the inner longitudinal channel section


42


′ into the inner end of the outer transverse channel section


43


′ following return of piston


70




f


to the extended position. It should be appreciated that, depending on the length of the outer transverse channel section


43


′, no gap need be present between the products therein, in which case the stroke of piston


70




f


can be equivalent to the dimension D


2


so that the product or products is/are pulled or moved by piston


7


Of an increment equivalent to one product width.




Actuator


66




g


serves to push a product


47


at the outer end of the outer transverse channel section


43


′ into the outer longitudinal channel section


45


′. The actuator


66




g


is similar to actuators


66




a,




66




b,




66




c,




66




d


and


66




e


and includes cylinder


68




g


mounted within, on or to the side wall


38


, externally of channel


41


, with its piston


70




g


longitudinally or axially aligned with the outer longitudinal channel section


45


′. The longitudinal axis of piston


70




g


is parallel to plane P


1


; and, when the piston


70




g


is in the retracted position, the product engaging end


74




g


thereof is aligned or flush with or is disposed within a recess in the interior surface of side wall


38


. Accordingly, a product


47


is capable of being moved into the outer end of outer transverse channel section


43


′ in response to actuation of actuator


66




f


as described above. The thusly moved product


47


will have its major axis or external dimension D


1


longitudinally or axially aligned with the outer longitudinal channel section


45


′ and will have its minor axis or external dimension D


2


longitudinally or axially aligned with the outer transverse channel section


43


′, the outer transverse channel section


43


′ being longitudinally aligned and continuous with the outer longitudinal channel section


45


′.




When the piston


70




g


is thereafter moved from the retracted position to the extended position, the product


47


disposed at the outer end of the outer transverse channel section


43


′ is engaged, from behind, by product engaging end


74




g


such that a pushing force is applied to the forward end


80


of the product in the direction of its major axis. The product disposed at the outer transverse channel section


43


′ is thusly moved or advanced a single position or increment in the longitudinal direction parallel to plane P


1


as shown in FIG.


3


. Accordingly, the product disposed at the outer end of the outer transverse channel section


43


′ is moved into the outer longitudinal channel section


45


′ causing products


47


in the outer longitudinal channel


45


′ to be correspondingly moved or advanced a single position or increment. The products


47


moved by actuator


66




g


are moved in the longitudinal direction, parallel to plane P


1


, with the major axis or external dimension D


1


longitudinally or axially aligned with the longitudinal direction of movement. The longitudinal direction of movement for products advanced by actuator


66




g


is in the same direction as the longitudinal direction of movement for products


47


advanced by actuator


66




c.


The major axis or external dimension D


1


of the products moved by actuator


66




g


remains parallel to plane P


1


. When the piston


70




g


is moved back to the retracted position, a next subsequent product


47


is able to be moved into the outer end of the outer transverse channel section


43


′ in response to actuation of actuator


66




f.


When the piston


70




g


is moved to the extended position after a subsequent product has been moved into the outer end of the outer transverse channel section


43


′, the subsequent product and preceding products are advanced a single position due to end to end contact or abutment between the products.




In the case of product irradiation device


10


, the outer longitudinal channel section


45


′ has a length that is the same as the length of the outer longitudinal channel section


45


, and the stroke for piston


70




g


is the same as that for piston


70




a.


When a product at the outer end of the outer transverse channel section


43


′ is pushed by actuator


66




g,


a single next preceding product in outer longitudinal channel section


45


′ is thereby pushed through the outlet port


46


′ and is discharged onto the first end of the discharge member


64


. The product


47


that is discharged onto the first end of the discharge member


64


is automatically conveyed, by gravity, toward the second end of the discharge member allowing a next subsequent product


47


to be discharged onto the first end thereof the next time that piston


70




g


is moved to the extended position. Products


47


are conveyed along the discharge member


64


in a transverse direction perpendicular to plane P


1


while the major axis or external dimension D


1


of the products remains parallel to plane P


1


. The transverse direction of movement for products


47


along the discharge member


64


is in the same direction as the transverse direction of movement for products


47


along the delivery member


60


and within the outer transverse channel sections


43


and


43


′ and the inner transverse channel section


44


.




The fluid used to operate the actuators may comprise a liquid or a gas, such as compressed air. A fluid supply system (not shown) including a fluid source, conduits for supplying fluid to the cylinders from the fluid source and valves for controlling the pressure of fluid in the cylinders is disposed externally of the shell


14


and, preferably, is disposed within the interior of enclosure


12


. A control system (not shown) for effecting automatic, timed extension and retraction of the pistons, individually or in selective unison, is also disposed externally of shell


14


and, preferably, within the interior of enclosure


12


. In particular, the control system is adapted, via an appropriate software program, to effect automatic, simultaneous extension and retraction of pistons


70




a,




70




c,




70




e


and


70




g


in alternating sequence with simultaneous extension and retraction of pistons


70


b,


70




d


and


70




f.


The control system preferably includes computer software and a control panel by which extension and retraction of particular pistons can be selected and by which the timing for extension and retraction of the pistons can be selected and adjusted as desired to control the speed with which the products


47


are moved through the transport channel


41


. The excess space in enclosure


12


may be used to store additional rods


50


as well as machinery for removing and inserting the rods


50


in transport containers and for removing and replacing rods


50


within the shell


14


. In particular, the enclosure


12


will have a storage container therein, capable of storing the rods


50


after receipt from the supplier. The delivery and discharge members


60


and


64


may also be stored in the interior of enclosure


12


when the product irradiation device


10


is not in use.




Preferably, the control system is adapted to provide verification of piston movement and, therefore, proper operation or actuation of the actuators. The control system can include an indicator, such as an alarm, to provide an indication of malfunction of the actuators. For example, the indicator can be responsive to failure of one or more of the pistons to properly extend and/or retract. The control system can also be adapted to identify the location or locations of a malfunction or malfunctions, such as identification of a particular piston or pistons that does/do not properly extend and/or retract.




According to a preferred embodiment of the product irradiation device


10


, the enclosure


12


has an interior length of approximately 52.5 feet, an interior width of approximately 99 inches and an interior height of approximately 110 inches. The shell


14


has an overall length, between exterior surfaces of end wall


37


and side wall


38


, of approximately 5 feet, 4¼ inches, a major width, between exterior surfaces of end walls


40


and


40


′, of approximately 7 feet, 4½ inches, a minor width, between exterior surfaces of side walls


36


and


36


′, of approximately 3 feet, 10½ inches and a height, between exterior surfaces of upper and lower walls


34


and


35


, of approximately 45 inches. The active length for irradiation source


49


is approximately 8 feet, 3 inches. An interior width of shell


14


, between interior surfaces of side walls


36


and


36


′ is approximately 22½ inches. Rods


50


may be conventional, such as the Cobalt 60 rods supplied by MDS Nordian of Canada and Reviss/Puridec of the United Kingdom. Typical rods have a diameter of 0.380 inch and an active length of 16.0 inches. In the preferred embodiment, each rod


50


has a radiation strength or intensity of 10,000 curies, and one hundred twenty rods


50


are linearly arranged in the shell insert. The tubes


51


are preferably made of stainless steel and have an outer diameter of 0.5 inch. The faces of shell insert


53


are made of stainless steel, and the shell insert has an inner width, defined between interior surfaces of side faces


54


and


54


′ of 0.5 inch. The shield plugs


55


are preferably made of stainless steel. It should be appreciated that the specific dimensions of the enclosure, the shell, the irradiation source, the tubes and the shell insert can vary and that the specific dimensions described herein for a preferred embodiment should be considered exemplary. Similarly, the various dimensions of the transport channel can vary, and greater or fewer numbers of products can be accommodated in the various transport channel sections than those illustrated herein by way of example. Furthermore, corresponding sections of the transport channel do not have to accommodate the same number of products.




The products


47


are illustrated in

FIGS. 2 and 3

as boxed products, each comprising a box made of a radiation penetrable material and a product, object, substance or material, such as food, to be irradiated disposed within the box. As an example, each product


47


may comprise a plurality of preformed hamburgers enclosed in a sealed box. The boxes of products


47


have a rectangular configuration including a pair of planar, parallel, outer and inner sides


78


and


78


′, respectively, a pair of planar, parallel, upper and lower sides


79


and


79


′, respectively, and a pair of planar, parallel, forward and rearward ends


80


and


80


′, respectively, connecting sides


78


,


78


′,


79


and


79


′ as shown in FIG.


2


. However, it should be appreciated that the product irradiation device


10


can be used to irradiate various types of naturally and artificially produced or created products including boxed products and non-boxed products as well as products having different sizes and configurations. As a further example, the products to be irradiated may comprise flowers or other plant material, the irradiation of which results in relatively longer shelf/vase life and increased freshness. In the case of products


47


, the boxes thereof are irradiated in order to enhance the quality of the products, substances or materials disposed within the boxes. However, it should be appreciated that products, substances or materials to be irradiated can be irradiated using the product irradiation device


10


without being disposed or enclosed in boxes or other containers.





FIG. 5

illustrates a modification of products to be irradiated in accordance with the present invention.

FIG. 5

illustrates a basket


147


containing a plurality of smaller, individual packages or objects


157


to be irradiated. A plurality of baskets


147


can be supplied for use with the product irradiation device, and the packages or objects


157


are placed in the baskets


147


prior to passage of the baskets


147


through the product irradiation device. Each basket has a bottom


181


to be disposed upon and in contact with the transport surface when the baskets


147


are moved through the transport channel. The baskets


147


are continuously moved into, through and out of the product irradiation device in the same manner as described herein for boxes


47


. The objects


157


can be of variable sizes or can be the same size. In

FIG. 5

, the objects


157


are shown as packages of different, variable sizes.




As shown in dotted lines in

FIG. 2

, the products


47


can be provided with a radiation monitoring or indicating device


82


. The radiation monitoring or indicating device


82


is disposed on an outer surface of the box of a product


47


, such as being disposed on the outer surface of inner side


78


′. The radiation monitoring or indicating device


82


is capable of providing a visual indication, for example a color change, of exposure of product


47


to the proper dose of radiation.




In the case of products


47


, the products, substances or materials to be irradiated are normally placed and sealed in the boxes as part of their manufacturing or processing procedures. Accordingly, the products


47


may be irradiated subsequent to manufacture or processing without any additional handling, exposure to the environment or other interference with the products, materials or substances disposed inside the boxes. The length of sides


78


,


78


′,


79


and


79


′ between ends


80


and


80


′ corresponds to the external dimension D


1


of the products


47


. The distance between outer and inner sides


78


and


78


′ corresponds to the external dimension D


2


of the products


47


. The external dimensions D


1


and D


2


correspond to the length and width, respectively, of products


47


. The distance between upper and lower sides


79


and


79


′ corresponds to the height of products


47


, which is smaller than D


1


but larger than D


2


.




In a method of irradiating products, such as products


47


, according to the present invention, the pair of doors


20


defining the entry and discharge openings, respectively, of enclosure


12


are opened. The delivery member


60


is positioned to extend through the entry opening with the first end of the delivery member positioned directly in front of the inlet port


46


and the second end of the delivery member positioned at a location at or proximate the source, such as a manufacturing or processing facility, of the products


47


. Similarly, the discharge member


64


is positioned to extend through the discharge opening with the first end of the discharge member positioned directly in front of the outlet port


46


′ and the second end of the discharge member positioned at a different location at or proximate the source. The products


47


are supplied sequentially to the second end of the delivery member


60


manually or mechanically via suitable machinery. Each product


47


is positioned on the delivery member with one of its lower sides


79


′ disposed upon and in contact with the rollers of the delivery member


60


. The products


47


are automatically conveyed or moved, due to gravity, in sequence along the delivery member


60


such that the most preceding product


47


on the delivery member


60


arrives at the first end thereof, the products being guided along the delivery member by the side rails


62


. The products


47


are positioned on and conveyed along the delivery member


60


with the major axis or external dimension D


1


parallel to plane P


1


. The products


47


are moved along the delivery member


60


in the transverse direction perpendicular to plane P


1


, and the exterior surface of the side wall


36


serves as a stop or abutment for a product when it arrives at the first end of the delivery member, whereby a product disposed at the first end of the delivery member


60


is longitudinally or axially aligned with the inlet port


46


and the outer longitudinal channel section


45


. When operation of the product irradiation device


10


is initially commenced or started up, the most preceding product


47


on the delivery member will be a lead product.




The actuator


66




a


is operated as described above, individually or simultaneously with actuators


66




c,




66




e


and


66




g,


to push the product


47


disposed at the first end of the delivery member


60


through the inlet port


46


into the outer longitudinal channel section


45


such that the product is advanced a single increment or position. Where the product


47


at the first end of the delivery member


60


is the lead product, as during initial start up, no preceding products


47


are disposed in channel


41


to be moved by the lead product or by the actuators


66




c,




66




e


and


66




g.


It should be appreciated, therefore, that actuator


66




a


can be actuated individually during start up without actuation of actuators


66




c,




66




e


and


66




g.


When the actuators


66




b,




66




d


and


66




f


are actuated subsequent to actuation of actuators


66




a,




66




c,




66




e


and


66




g,


i.e, following retraction of pistons


70




a,




70




c,




70




e


and


70




g,


no preceding products are disposed in channel


41


to be moved or advanced thereby where the product previously moved into the channel


41


through the inlet port


46


is the lead product. It should be appreciated, therefore, that the actuator


66




a


can be actuated individually or simultaneously with actuators


66




c,




66




e


and


66




g


in sequential repetition during initial start up, without actuation of actuators


66




b,




66




d


and


66




f,


until the lead product has arrived at the outer end of outer transverse channel section


43


. Once the lead product


47


has been pushed through the inlet port


46


into the outer longitudinal channel section


45


, the next successive or subsequent product


47


arrives at the first end of the delivery member


60


and is longitudinally or axially aligned with the inlet port


46


. When the actuator


66




a


is thereafter actuated, individually or simultaneously with actuators


66




c,




66




e


and


66




g,


the next subsequent product


47


now disposed on the first end of the delivery member


60


is pushed through the inlet port


46


into the outer longitudinal channel section


45


, correspondingly moving the next preceding product, i.e. the lead product


47


, into the outer end of the outer transverse channel section


43


. Accordingly, each time a product


47


is pushed by piston


70




a


through the inlet port


46


from the first end of the delivery member, the next subsequent product


47


on the delivery member is automatically conveyed to the first end thereof, following retraction of the piston


70




a,


and is ready to be moved through the inlet port into the shell


14


. Similarly, each time a product


47


is pushed by piston


70




a


through the inlet port


46


into the outer longitudinal channel section


45


, the forward end


80


of that product engages, abuts or contacts the rearward end


80


′ of the next preceding product and thereby pushes the next preceding product into the outer end of the outer transverse channel section


43


.




Once the lead product


47


has arrived at the outer end of the outer transverse channel section


43


, the actuator


66




b


is actuated, individually or simultaneously with actuators


66




d


and


66




f,


to push the lead product toward the inner end of the outer transverse channel section


43


whereby the lead product is advanced to the next position in channel


41


. The next time that the actuator


66




a


is actuated following retraction of piston


70




b,


the product that is next subsequent to the lead product is moved from the outer longitudinal channel section


45


into the outer end of the outer transverse channel section


43


. When the actuator


66




b


is thereafter actuated individually or simultaneously with actuators


66




d


and


66




f,


following retraction of piston


70




a


and piston


70




c


(if previously extended), the next subsequent product disposed at the outer end of outer transverse channel section


43


is pushed by piston


70




b.


The inner side


78


′ of the next subsequent product engages, abuts or contacts the outer side


78


of the lead product and moves the lead product into the inner end of the outer transverse channel section


43


.




Following retraction of piston


70




b,


the actuators


66




a


and


66




c


are actuated simultaneously, with or without simultaneous actuation of actuators


66




e


and


66




g,


to push another subsequent product from the first end of the delivery member


60


through the inlet port


46


into the outer longitudinal channel section


45


and to simultaneously push the lead product disposed at the inner end of outer transverse channel section


43


into the first end of the inner longitudinal channel section


42


. As the another subsequent product is moved through the inlet port into the outer longitudinal channel section


45


, the product next preceding thereto is moved from the outer longitudinal channel section


45


into the outer end of outer transverse channel section


43


via abutment of the forward end of the another subsequent product with the rearward end of the product next preceding thereto.




The actuator


66




b


is actuated, individually or simultaneously with actuators


66




d


and


66




f,


following retraction of pistons


70




a


and


70




c.


As a result thereof, the product disposed at the outer end of the outer transverse channel section


43


is pushed by piston


70




b


and is advanced a single increment. As the product disposed at the outer end of the outer transverse channel section


43


is advanced by piston


70




b,


its inner side


78


′ engages, contacts or abuts the outer side


78


of the next preceding product, which is next subsequent to the lead product. Accordingly, the product that is next subsequent to the lead product is moved into the inner end of the outer transverse channel section


43


. The actuators


66




a


and


66




c


continue to be actuated simultaneously, with or without simultaneous actuation of actuators


66




e


and


66




g,


in alternating sequence with actuation of actuator


66




b,


with or without simultaneous actuation of actuators


66




d


and


66




f.


In this manner, products


47


continue to be advanced a single position or increment in channel


41


. Once six products


47


are disposed in inner longitudinal channel section


42


, the lead product disposed at the second end thereof is moved into the outer end of inner transverse channel section


44


the next time the actuators


66




a


and


66




c


are simultaneously actuated, with or without simultaneous actuation of actuators


66




e


and


66




g.






Once the lead product has been moved from the second end of the inner longitudinal channel section


42


into the outer end of inner transverse channel section


44


, actuator


66




d


is actuated simultaneously with actuator


66




b,


with or without simultaneous actuation of actuator


66




f,


following retraction of pistons


70




a


and


70




c.


Actuation of actuator


66




d


causes the product at the outer end of inner transverse channel section


44


, i.e. the lead product, to be moved into the opposite, outer end of the inner transverse channel section


44


. Simultaneous actuation of actuator


66




b


therewith causes a most preceding product in the outer transverse channel section


43


to be moved into the inner end thereof. Following return of pistons


70




b


and


70




d


to the retracted position, actuator


66




e


is actuated simultaneously with actuators


66




a


and


66




c,


with or without simultaneous actuation of actuator


66




g.


The lead product is moved by actuator


66




e


from the opposite, outer end of inner transverse channel section


44


into the second end of the inner longitudinal channel section


42


′. Simultaneously therewith, a new subsequent product is pushed by actuator


66




a


through the inlet port


46


into the outer longitudinal channel section


45


causing the product next preceding thereto to be moved into the outer end of the outer transverse channel section


43


. In addition, a product disposed at the inner end of the outer transverse channel section


43


is simultaneously pushed by actuator


66




c


into the first end of inner longitudinal channel section


42


causing a product disposed at the second end of the inner longitudinal channel section, i.e. the product next subsequent to the lead product, to be moved into the outer end of the inner transverse channel section


44


.




The actuators


66




b


and


66




d


are actuated simultaneously, with or without actuation of actuator


66




f,


in alternating sequence with simultaneous actuation of actuators


66




a,




66




c


and


66




e,


with or without actuation of actuator


66




g,


such that six products will be disposed in inner longitudinal channel section


42


′ in end to end relation, with the lead product


47


disposed at the first end of the inner longitudinal channel section


42


′. The next time actuators


66




a,




66




c


and


66




e


are simultaneously actuated, the lead product


47


is moved into the inner end of the outer transverse channel section


43


′.




Once the lead product


47


has been moved from the inner longitudinal channel section


42


′ into the inner end of outer transverse channel section


43


′, the actuator


66




f


is actuated simultaneously or in unison with actuators


66




b


and


66




d.


The lead product


47


disposed at the inner end of outer transverse channel section


43


′ is pulled by piston


70




f


toward the outer end of outer transverse channel section


43


′. Simultaneously therewith, the product at the outer end of outer transverse channel section


43


is advanced a single increment by piston


70




b


and the product at the outer end of inner transverse channel section


44


is moved to the opposite, outer end thereof by piston


70




d.


When the actuators


66




a,




66




c


and


66




e


are thereafter actuated simultaneously, the product that is next subsequent to the lead product is moved from the inner longitudinal channel section


42


′ into the inner end of outer transverse channel section


43


′, the product at the second end of inner longitudinal channel section


42


is moved into the outer end of inner transverse channel section


44


and the product in the outer longitudinal channel section


45


is moved into the outer end of outer transverse channel section


43


.




The next time actuators


66




b,




66




d


and


66




f


are simultaneously actuated, the lead product


47


disposed in outer transverse channel section


43


′ is moved into the outer end of outer transverse channel section


43


, the product next subsequent to the lead product is pulled by piston


70




f


a single increment, the product at the outer end of inner transverse channel section


44


is pushed by piston


70




d


to the opposite, outer end thereof, the product at the outer end of outer transverse channel section


43


is pushed by piston


70




d


a single increment and the product next preceding thereto is moved into the inner end of outer transverse channel section


43


. The actuators


66




a,




66




c,




66




e


and


66




g


are thereafter actuated simultaneously or in unison. As a result thereof, the lead product


47


at the outer end of outer transverse channel section


43


′ is pushed by piston


70




g


into the outer longitudinal channel section


45


′. In addition, the products in outer longitudinal channel section


45


and inner longitudinal channel sections


42


and


42


′ are each advanced a single position or increment as previously described. The actuators


66




b,




66




d


and


66




f


are thereafter simultaneously actuated to advance the products in the outer transverse channel sections


43


and


43


′ and the inner transverse channel section


44


as described above.




The next time actuators


66




a,




66




c,




66




e


and


66




g


are actuated simultaneously, the product that is disposed in the outer end of the outer transverse channel section


43


′ is moved therefrom into the outer longitudinal channel section


45


′ causing movement of the next preceding product, i.e. the lead product


47


, through the outlet port


46


′ for discharge onto the first end of the discharge member


64


. Simultaneously therewith, the products within the outer longitudinal channel section


45


and the inner longitudinal channel sections


42


and


42


′ are incrementally advanced as described above. The lead product


47


discharged onto the first end of the discharge member


64


is automatically conveyed, by gravity, toward the second end of the discharge member


64


for removal therefrom. As a result of continuous supply of products to the delivery member and continuous actuation or operation of actuators


66




a,




66




c,




66




e


and


66




g


in alternation with actuators


66




b,




66




d


and


66




f,


the products


47


are continuously introduced in, advanced through and discharged from the product irradiation device


10


.




Once the lead product has been discharged from the product irradiation device, initial start up will be completed. The transport channel will be filled to capacity with products to be irradiated, and normal operation of the product irradiation device will ensue. When the product irradiation device is to be shut down following establishment of normal operation, dummy products, similar in size and shape to the actual products


47


, are sequentially introduced and advanced in the transport channel in place of the actual products


47


until the last actual product


47


has been discharged therefrom. The transport channel will then be filled to capacity with dummy products, such as empty boxes, and the product irradiation device will be ready for shut down, which would typically occur during the third daily operating shift.




When the product irradiation device is thereafter restarted, typically at the beginning of the first daily operating shift, actual products


47


are introduced in and advanced through the transport channel, and the dummy products discharged from the device are retrieved. The retrieved dummy products can be saved for reuse. Once the last dummy product has been discharged from the product irradiation device, normal operation of the product irradiation device will ensue.




As the products


47


are moved through the transport channel


41


, they are moved past the irradiation source


49


. In particular, the products


47


are moved past the irradiation source


49


as they are moved through inner longitudinal channel sections


42


and


42


′, i.e. the high radiation zone. The products


47


have their external dimension D


1


disposed parallel to plane P


1


and, therefore, the irradiation source


49


, as they enter, move through and are discharged from the shell


14


. The inner side


78


′ of the products


47


faces the irradiation source


49


as the products move through the inner longitudinal channel section


42


, and the outer side


78


of the products faces the irradiation source


49


as the products move through the inner longitudinal channel section


42


′. The outer and inner sides


78


and


78


′ that face the irradiation source


49


during movement of the products


47


through the shell


14


constitute the major external dimension for the products


47


such that a major or maximum area or part of the products is exposed to the maximum radiation. Each product


47


has its lower side


79


′ in direct contact with the transport surface


48


, i.e. the interior surface of lower wall


35


. As the products


47


enter, move through and are discharged from the transport channel


41


, the lower sides


79


′ remain in contact with the transport surface


48


. The parallel orientation of the major axis or external dimension D


1


with the plane P


1


as the products enter, move through and are discharged from the shell


14


is maintained by the close correspondence of the cross-sectional size and configuration of the transport channel


41


to the external cross-sectional sizes and configurations of the products. Accordingly, as the products are moved through the shell, opposite sides of the products are irradiated without requiring rotation of the products or other undesired displacement of the products from their parallel orientation with plane P


1


.




The products


47


enter the shell


14


on one side of the enclosure


12


and are discharged from the shell


14


on an opposite side of the enclosure


12


. In particular, the products


47


enter the enclosure


12


at a location disposed on side wall


17


and exit the enclosure


12


at a location disposed on the side wall


17


′. Accordingly, the products


47


enter and exit the product irradiation device


10


at different, remote locations such that nonirradiated products entering the product irradiation device


10


should not become confused or intermingled with irradiated products exiting the product irradiation device


10


.




In the preferred method of irradiating products, the actuators


66




a,




66




c,




66




e


and


66




g


are actuated simultaneously in alternating sequence with simultaneous actuation of actuators


66




b,




66




d


and


66




f


in ten second intervals. Accordingly, ten seconds after the pistons


70




a,




70




c,




70




e


and


70




g


are simultaneously extended, the pistons


70




b


and


70




d


are simultaneously extended and the piston


70




f


is retracted simultaneously with extension of pistons


70




b


and


70




d.


The pistons


70




a,




70




c,




70




e


and


70




g


are again simultaneously extended ten seconds after simultaneous extension of pistons


70




b


and


70




d


and retraction of piston


70




f,


and so on. A new product


47


will enter the shell


14


every ten seconds, and each product will spend approximately three minutes in the shell


14


passing through the transport channel


41


. It should be appreciated, however, that the speed of movement of the products through the transport channel can be adjusted by adjusting the intervals at which new products are introduced in the transport channel and by adjusting the timing for extension and retraction of the pistons. For example, it may be desirable to decrease the speed of the products through the transport channel to increase the dosage of radiation imparted to the products. The speed of the products may also be adjusted to account for decay of the irradiation source. For example, the speed of products through the shell may be decreased to offset radioactive decay of rods


50


.




In an alternative embodiment, the shell


14


can be rotated, as shown by the arrow


84


in

FIG. 2

, 90 degrees from the position shown in FIG.


2


. The upper and lower walls


34


and


35


, respectively, will then define side walls for the shell


4


, the side wall


36


, side wall segment


39


and end wall


40


will define an upper wall for the shell


14


, and the side wall


36


′, side wall segment


39


′ and end wall


40


′ will define a lower wall for the shell


14


. In this orientation, the inlet port


46


will be disposed along a top of the shell


14


, and the outlet port


46


′ will be disposed along a bottom of the shell


14


. Of course, the delivery and discharge members can be modified, as necessary, to permit gravity conveyance of products to the inlet port


46


and gravity conveyance of products away from the outlet port


46


′. Where the shell


14


is rotated 90 degrees, a suitable enclosure for the shell can be provided, the enclosure having entry and exit openings establishing communication with the inlet and outlet ports, respectively, from externally of the enclosure.




By rotating the shell 90°, the plane P


1


of the irradiation source will be oriented horizontally rather than vertically as in the case of shell


14


. In this manner, products will pass above and below the irradiation source rather than passing the irradiation source on opposite sides thereof as in the case of product irradiation device


10


. In order to illustrate this arrangement,

FIG. 3

can be considered representative of a side view of a modified shell that has been rotated 90° and, in particular, a side view of shell


14


rotated 90°. When thusly rotated, the shell


14


can be modified so that the inlet port


46


and the outlet port


46


′ are not located at the top and bottom, respectively, of the shell. For example, it may be desirable for the inlet and outlet ports


46


and


46


′ to be disposed on opposite sides of or on the same side of the shell. Accordingly, as an example, the outer longitudinal channel section


45


and the outer transverse channel section


43


can be disposed in the same plane or at the same elevation as the inner longitudinal channel section


42


so that the transport surfaces of the outer longitudinal channel section


45


, the outer transverse channel section


43


and the inner longitudinal channel section


42


are all disposed in the same plane, such plane being parallel to the plane P


1


of the irradiation source. Similarly, the outer longitudinal channel section


45


′ and the outer transverse channel section


43


′ can be disposed in the same plane or at the same elevation as the inner longitudinal channel section


42


′ so that the transport surfaces of the outer longitudinal channel section


45


′, the outer transverse channel section


43


′ and the inner longitudinal channel section


42


′ are all disposed in the same plane, such plane being parallel to the plane P


1


of the irradiation source and the plane containing the transport surfaces of channel sections


42


,


43


and


45


. With this approach, vertical lowering of the products is needed at only one location in that the products would only need to be vertically lowered from the outer end to the inner end of the inner transverse channel section


44


, the outer and inner ends of channel section


44


now being upper and lower ends thereof since the channel section


44


is oriented vertically due to rotation of the shell


14


by 90°.




The modified shell design discussed above is particularly amenable to irradiating relatively small objects or packages contained in baskets. The modified shell design allows products to be transported through the shell with bottoms, rather than sides, of the products, such as bottoms of the baskets, disposed and supported on the transport surface, thusly minimizing concerns with product shifting within containers, boxes or baskets as could occur when the containers, boxes or baskets are supported or placed on their sides when passing through the transport channel. In the modified shell design, the inlet and outlet ports may be located on the same side of the shell in order to minimize total width of the device.




No moving mechanical parts are disposed in the high radiation zone of the shell


14


which would require access to the interior of the shell


14


in order to perform maintenance and/or repair. The pistons


70


are disposed outside of or beyond the high radiation zone. Each of the cylinders


68


is mounted externally of the transport channel


41


, either on, to or within the walls of the shell, allowing the actuators to be accessed externally of the shell interior in order to perform maintenance and/or repair. The actuators are simple linear devices that are easily removable and replaceable for maintenance without removing the irradiation source from the device. The transport surface


48


, upon and along which the products are moved, is formed by an interior surface or surfaces of the shell


14


without requiring any moving support surfaces or parts. The products are irradiated at the processing or manufacturing facility or other source thereof and are ready for transport or distribution immediately upon discharge from the irradiation device. The prescribed path for the products through the shell is uncomplicated and eliminates or reduces the risk of malfunction and/or damage to the products being irradiated. Human operation or intervention is greatly minimized in that irradiation is accomplished automatically once the control system has been set to select a desired automatic, timed operation for the actuators. Various natural or artificially created products can be irradiated with the product irradiation device.




The irradiator shell


14


and the arrangement of the prescribed path therethrough allow the size of the irradiator shell to be minimized for reduced cost and material needs. The actuators are simple and uncomplicated and are compatible for use with various types of products to be irradiated. The strokes or extensions of the pistons can vary in accordance with the dimensions of the products and the distance that the products must be moved in the transport channel. The size and configuration of the inlet and outlet ports may closely correspond to the size and configuration of the products to minimize excess space or gaps at the inlet and outlet ports. The size and configuration of the inlet and outlet ports as well as the cross-sectional size and configuration of the transport channel are preferably no larger than necessary to accommodate the products therein so as to eliminate or greatly reduce the risk of inadvertent human access to the interior of the shell. Accordingly, the inlet and outlet ports are sized to prevent or preclude human access passively, without any interlocks and/or opening/closing mechanisms. The product engaging ends of the actuators can have various configurations in accordance with the characteristics of the products to be engaged thereby, and the product engaging ends may have planar or non-planar surfaces. Depending on the cross-sectional size of the transport channel, the product engaging ends do not have to be aligned or flush with or disposed within the walls of the shell in the retracted position but, rather, can protrude into the transport channel. The pistons of the actuators can be mounted for movement within the wall or walls of the shell with only the product engaging ends thereof protruding into the transport channel in the extended position to engage the products to be moved thereby.




The product irradiation device is intended to be fabricated offsite and can be assembled and tested prior to shipment to the site at which product irradiation is to take place. The product irradiation device can be shipped as two or more subassemblies, which are reassembled on site.




It should be appreciated that the subject invention is subject to various modifications, variations and changes in detail. Accordingly, the foregoing description of the preferred embodiments should be considered illustrative only and should not be taken in a limiting sense.



Claims
  • 1. A product irradiation device for irradiating products comprisinga transportable enclosure defining an interior and having an entry opening through which products enter said enclosure and having an exit opening through which the products exit said enclosure; an irradiator shell disposed in said interior and comprising a wall enclosing an irradiation source and a transport channel, said transport channel having an inlet port, disposed along an exterior surface of said wall, communicating with said entry opening by which the products enter said transport channel and having an outlet port, disposed along an exterior surface of said wall, communicating with said exit opening by which the products are discharged from said transport channel, said transport channel defining a prescribed path for the products through said shell and past said irradiation source, said outlet port being spaced from said inlet port, said transport channel including a transport surface upon which the products are supported in contact with said transport surface and are moved in said prescribed path from said inlet port to said outlet port, said transport surface being formed by an interior surface of said wall, said interior surface being non-moving from said inlet port to said outlet port; and a plurality of linear actuators mounted to said shell for moving the products into, through and out of said transport channel whereby the products are moved in said prescribed path past said irradiation source and are thereby irradiated prior to being discharged through said outlet port.
  • 2. A product irradiation device as recited in claim 1 wherein said inlet and outlet ports are disposed in a plane and said irradiation source includes a plurality of rods of radioactive material arranged in said shell to be disposed in a plane perpendicular to said plane of said inlet and outlet ports.
  • 3. A product irradiation device as recited in claim 2 wherein said inlet port is disposed on one side of said plane of said rods and said outlet port is disposed on an opposite side of said plane of said rods.
  • 4. A product irradiation device as recited in claim 1 wherein said transport channel is adapted to receive the products therein with a side of each of the products in contact with said transport surface as the products are moved through said transport channel.
  • 5. A product irradiation device as recited in claim 1 wherein said transport channel is adapted to receive the products therein with a bottom of each of the products in contact with said transport surface as the products are moved through said transport channel.
  • 6. A product irradiation device as recited in claim 2 wherein said transport channel includes inner longitudinal channel sections disposed on opposite sides of said plane of said rods, said inner longitudinal channel sections being parallel to said plane of said rods, said rods being disposed in linear series between said inner longitudinal channel sections, said inner longitudinal channel sections defining a high radiation zone within said shell, said actuators including slidably movable pistons, respectively, movable between extended and retracted positions to move the products into, through and out of said transport channel, said pistons being disposed outside of said high radiation zone such that no moving mechanical parts are disposed in said high radiation zone.
  • 7. A product irradiation device as recited in claim 6 wherein the products have an external longitudinal dimension and said actuators move the products into, through and out of said transport channel with the external longitudinal dimension disposed parallel to said plane of said rods.
  • 8. A product irradiation device as recited in claim 1 wherein said irradiation source includes a plurality of rods of radioactive material arranged in said shell to be disposed in a plane and said transport surface is planar and perpendicular to said plane of said rods.
  • 9. A product irradiation device as recited in claim 1 wherein said irradiation source includes a plurality of rods of radioactive material arranged in said shell to be disposed in a plane and said transport surface is planar and parallel to said plane of said rods.
  • 10. A product irradiation device as recited in claim 1 wherein the products have an external cross-section and said transport channel has a cross-section closely corresponding to the external cross-section of the products.
  • 11. A product irradiation device as recited in claim 10 wherein said cross-section of said transport channel is non-uniform between said inlet port and said outlet port.
  • 12. A product irradiation device as recited in claim 1 wherein said irradiation source is disposed in a plane and said inlet and outlet ports are disposed in a plane perpendicular to said plane of said irradiation source, said transport channel includes a first outer longitudinal channel section extending longitudinally from said inlet port in a direction parallel to said plane of said irradiation source, a first outer transverse channel section having an outer end communicating with said first outer longitudinal channel section, said first outer transverse channel section extending longitudinally in a direction perpendicular to said plane of said irradiation source from said outer end to an inner end of said first transverse channel section, a first inner longitudinal channel section having a first end communicating with said inner end of said first outer transverse channel section, said first inner longitudinal channel section extending longitudinally in a direction parallel to said plane of said irradiation source from said first end to a second end of said first inner longitudinal channel section, an inner transverse channel section having an outer end communicating with said second end of said first inner longitudinal channel section, said inner transverse channel section extending longitudinally in a direction perpendicular to said plane of said irradiation source from said outer end of said inner transverse channel section to an opposite outer end of said inner transverse channel section, a second inner longitudinal channel section having a second end communicating with said opposite outer end of said inner transverse channel section, said second inner longitudinal channel section being parallel to said first inner longitudinal channel section and extending longitudinally in a direction parallel to said plane of said irradiation source from said second end of said second inner longitudinal channel section to a first end of said second inner longitudinal channel section, a second outer transverse channel section parallel to said inner transverse channel section and having an inner end communicating with said first end of said second inner longitudinal channel section, said second outer transverse channel section extending longitudinally in a direction perpendicular to said plane of said irradiation source from said inner end of said second outer transverse channel section to an outer end of said second outer transverse channel section and a second outer longitudinal channel section parallel to said first outer longitudinal channel section and extending longitudinally in a direction parallel to said plane of said irradiation source from said outer end of said second outer transverse channel section to said outlet port, said plane of said irradiation source being disposed between said first and second inner longitudinal channel sections.
  • 13. A product irradiation device as recited in claim 12 wherein a first one of said actuators pushes the products, in a direction parallel to said plane of said irradiation source, through said inlet port into and through said first outer longitudinal channel section into said outer end of said first outer transverse channel section, a second one of said actuators pushes the products, in a direction perpendicular to said plane of said irradiation source, from said outer end of said first outer transverse channel section into said inner end of said first outer transverse channel section, a third one of said actuators pushes the products, in a direction parallel to said plane of said irradiation source, from said inner end of said first outer transverse channel section into and through said first inner longitudinal channel section into said outer end of said inner transverse channel section, a fourth one of said actuators pushes the products, in a direction perpendicular to said plane of said irradiation source, from said outer end of said inner transverse channel section into said opposite outer end of said inner transverse channel section, a fifth one of said actuators pushes the products, in a direction parallel to said plane of said irradiation source, from said opposite outer end of said inner transverse channel section into and through said second inner longitudinal channel section into said inner end of said second outer transverse channel section, a sixth one of said actuators pulls the products, in a direction perpendicular to said plane of said irradiation source, from said inner end of said second outer transverse channel section into said outer end of said second outer transverse channel section and a seventh one of said actuators pushes the products, in a direction parallel to said plane of said irradiation source, from said outer end of said second outer transverse channel section into and through said second outer longitudinal channel section and through said outlet port.
  • 14. A product irradiation device as recited in claim 13 wherein the products are moved in the same perpendicular direction within said first and second outer transverse channel sections and said inner transverse channel section, the products are moved in the same parallel direction within said first outer longitudinal channel section and said second inner longitudinal channel section, and the products are moved in the same parallel direction within said first inner longitudinal channel section and said second outer longitudinal channel section, the products being moved within said first inner longitudinal channel section and said second outer longitudinal channel section in a parallel direction opposite the parallel direction of movement of the products within said first outer longitudinal channel section and said second inner longitudinal channel section.
  • 15. A product irradiation device as recited in claim 14 wherein said actuators include cylinders, respectively, and pistons, respectively, longitudinally movable within said cylinders between retracted positions and extended positions, respectively, said pistons of said first one of said actuators being disposed externally of said shell in longitudinal alignment with said inlet port whereby a product is capable of being positioned in front of said inlet port in longitudinal alignment therewith when said piston is in said retracted position and is pushed by said piston through said inlet port into said first outer longitudinal channel section when said piston is moved to said extended position, said piston of said second one of said actuators being longitudinally aligned with said outer end of said first outer transverse channel section whereby a product is capable of being moved from said first outer longitudinal channel section into said outer end of said first outer transverse channel section when said piston of said second one of said actuators is in said retracted position and is pushed by said piston of said second one of said actuators from said outer end of said first outer transverse channel section toward said inner end of said first outer transverse channel section when said piston of said second one of said actuators is moved to said extended position, said piston of said third one of said actuators being longitudinally aligned with said first inner longitudinal channel section whereby a product is capable of being moved into said inner end of said first outer transverse channel section when said piston of said third one of said actuators is in said retracted position and is pushed by said piston of said third one of said actuators from said inner end of said first outer transverse channel section into said first end of said first inner longitudinal channel section when said piston of said third one of said actuators is moved to said extended position, said piston of said fourth one of said actuators being longitudinally aligned with said outer end of said inner transverse channel section whereby a product is capable of being moved from said second end of said first inner longitudinal channel section into said outer end of said inner transverse channel section when said piston of said fourth one of said actuators is in said retracted position and is pushed by said piston of said fourth one of said actuators from said outer end of said inner transverse channel section into said opposite outer end of said inner transverse channel section when said piston of said fourth one of said actuators is moved to said extended position, said piston of said fifth one of said actuators being longitudinally aligned with said second end of said second inner longitudinal channel section whereby a product is capable of being moved into said opposite outer end of said inner transverse channel section when said piston of said fifth one of said actuators is in said retracted position and is pushed by said piston of said fifth one of said actuators from said opposite outer end of said inner transverse channel section into said second end of said second inner longitudinal channel section when said piston of said fifth one of said actuators is moved to said extended position, said piston of a sixth one of said actuators being longitudinally aligned with said outer end of said second outer transverse channel section whereby a product is capable of being moved from said first end of said second inner longitudinal channel section into said inner end of said second outer transverse channel section when said piston of said sixth one of said actuators is in said extended position and is pulled by said piston of said sixth one of said actuators from said inner end of said second outer transverse channel section toward said outer end of said second outer transverse channel section when said piston of said sixth one of said actuators is moved to said retracted position, and said piston of said seventh one of said actuators being longitudinally aligned with said second outer longitudinal channel section whereby a product is capable of being moved into said outer end of said second outer transverse channel section when said piston of said seventh one of said actuators is in said retracted position and is pushed by said piston of said seventh one of said actuators from said outer end of said second outer transverse channel section into said second outer longitudinal channel section when said piston of said seventh one of said actuators is moved to said extended position.
  • 16. A product irradiation device as recite in claim 15 wherein said first, third, fifth and seventh ones of said actuators are adapted to be actuated simultaneously and said second, fourth and sixth ones of said actuators are adapted to be actuated simultaneously in alternating sequence with simultaneous actuation of said first, third, fifth and seventh ones of said actuators.
  • 17. A product irradiation device as recited in claim 16 wherein said pistons include product engaging ends, respectively, for engaging the products, respectively, moved thereby.
  • 18. A product irradiation device as recited in claim 1 wherein said irradiation source includes a plurality of rods of radioactive material and said rods are capable of being safely removed from and inserted in said shell while the products are being moved through said transport channel.
  • 19. A product irradiation device as recited in claim 1 wherein said actuators are hydraulic actuators.
  • 20. A product irradiation device as recited in claim 1 wherein said actuators are pneumatic actuators.
  • 21. A product irradiation device as recited in claim 1 and further including a delivery member extending through said entry opening when said entry opening is open for supplying the products to said shell and having a first end communicating with said inlet port and a second end disposed externally of said enclosure and a discharge member extending through said exit opening when said exit opening is open for transporting the products away from said shell after being discharged from said outlet port and having a first end communicating with said outlet port and a second end disposed externally of said enclosure.
  • 22. A product irradiation device for irradiating products comprisingan irradiator shell comprising a wall enclosing an irradiation source and a transport channel defining a prescribed path within said shell past said irradiation source, said wall having an inlet port therein communicating with said transport channel by which products, prior to being irradiated, enter said transport channel and having an outlet port therein communicating with said transport channel by which products, subsequent to being irradiated, are discharged from said transport channel, said transport channel including a solid transport surface upon which the products are supported in contact with said transport surface and are moved in said prescribed path from said inlet port to said outlet port, the solidity of said solid transport surface being continuous and without interruption from said inlet port to said outlet port; a plurality of actuators mounted to said shell for moving the products into, through and out of said transport channel whereby the products are moved in said prescribed path past said irradiation source and are thereby irradiated prior to being discharged through said outlet port; and a transportable enclosure defining an interior receiving said shell, said enclosure including an upper wall, a lower wall upon which said shell is supported, a pair of opposing side walls and a pair of end walls together defining said interior, said enclosure having an entry opening through which the products, prior to being irradiated, enter said inlet port of said shell and having an exit opening through which the products, subsequent to being irradiated, exit said enclosure after being discharged through said outlet port of said shell, said entry opening being separate from said exit opening to avoid intermingling of non-irradiated and irradiated products.
  • 23. A product irradiation device as recited in claim 22 wherein said entry opening is disposed along one of said side walls of said enclosure and said exit opening is disposed along the other of said side walls of said enclosure.
  • 24. A product irradiation device as recited in claim 23 wherein said inlet port is separate from said outlet port.
  • 25. A product irradiation device as recited in claim 22 and further including a plurality of wheels upon which said enclosure is mounted for transport along the ground.
  • 26. A product irradiation device as recited in claim 22 and further including an HVAC module on said enclosure adapted to effect heating, ventilation and cooling of said interior.
  • 27. A product irradiation device as recited in claim 26 and further including a generator module on said enclosure adapted to provide electric power for said enclosure.
  • 28. A product irradiation device as recited in claim 22 wherein said entry opening is defined by at least one first door on said enclosure and said exit opening is defined by at least one second door on said enclosure.
  • 29. A product irradiation device as recited in claim 28 wherein said enclosure is a truck trailer.
  • 30. A product irradiation device as recited in claim 22 wherein said transport surface is made of stainless steel.
  • 31. A product irradiation device as recited in claim 22 and further including a delivery member extending through said entry opening when said entry opening is open and having a first end removably disposed in communication with said inlet port and a second end disposed at a location proximate a source of the products, said delivery member being adapted to passively convey the products from said second end to said first end thereof, and a discharge member extending through said exit opening when said exit opening is open and having a first end removably disposed in communication with said outlet port and a second end disposed at a different location proximate the source of the products, said discharge member being adapted to passively convey the products discharged through said outlet port to said second end of said discharge member.
  • 32. A product irradiation device as recited in claim 31 wherein said delivery member and said discharge member are roller ramps, respectively, positioned at angles, respectively, to said enclosure for conveying the products therealong by gravity.
  • 33. A method of irradiating products comprising the steps ofintroducing products, prior to being irradiated, in succession through an inlet port of an irradiator shell and into a transport channel of the irradiator shell such that the products are supported upon and in contact with a transport surface of the shell which is non-moving from the inlet port to an outlet port of the shell; moving the products relative to and upon the transport surface in fixed increments such that the products are moved through the transport channel past an irradiation source within the shell and are thereby irradiated, said step of moving including moving the products from the inlet port to the outlet port while the products remain supported upon and in contact with the transport surface; and discharging the products, subsequent to being irradiated, in succession through the outlet port of the irradiator shell disposed at a location different from the inlet port.
  • 34. A method of irradiating products as recited in claim 33 wherein said step of introducing includes continuously introducing products in succession through the inlet port and said step of discharging includes continuously discharging products in succession from the outlet port.
  • 35. A method of irradiating products as recited in claim 34 wherein the irradiation source is disposed in a plane and said steps of introducing, moving and discharging include introducing, moving and discharging the products with a major dimension of the products disposed parallel to the plane of the irradiation source.
  • 36. A method of irradiating products as recited in claim 35 wherein said steps of introducing, moving and discharging include introducing, moving and discharging the products with the length of the products disposed parallel to the plane of the irradiation source.
  • 37. A method of irradiating products as recited in claim 36 wherein said step of moving includes moving the products in the transport channel with the products directly supported upon the transport surface.
  • 38. A method of irradiating products as recited in claim 37 wherein said step of moving includes actuating a plurality of linear actuators to extend and retract pistons, respectively, of the actuators to advance the products through the transport channel in the fixed increments.
  • 39. A method of irradiating products as recited in claim 38 wherein the transport channel includes first and second inner longitudinal channel sections parallel to the plane of the source and between which the irradiation source is disposed, an inner transverse channel section, perpendicular to the plane of the irradiation source, extending between ends of the first and second inner longitudinal channel sections, respectively, first and second outer longitudinal channel sections, parallel to the plane of the irradiation source, between which the first and second inner longitudinal channel sections are disposed and first and second outer transverse channel sections, perpendicular to the plane of the irradiation source, extending between opposite ends of the first and second inner longitudinal channel sections and the first and second outer longitudinal channel sections, respectively, and said step of moving includes moving products disposed in the first and second inner and outer longitudinal channel sections simultaneously in a direction parallel to the plane of the irradiation source and moving products disposed in the inner transverse channel section and the first and second outer transverse channel sections simultaneously in a direction perpendicular to the plane of the irradiation source in alternating sequence with simultaneous movement of the products in the first and second inner and outer longitudinal channel sections.
  • 40. A method of irradiating products as recited in claim 39 wherein said step of moving includes simultaneously actuating some of the actuators to simultaneously move the products in the first and second inner and outer longitudinal channel sections, respectively, and simultaneously actuating others of the actuators to simultaneously move the products in the inner transverse channel section and the first and second outer transverse channel sections, respectively, in alternating sequence with simultaneous actuation of the some of the actuators.
  • 41. A method of irradiating products as recited in claim 40 wherein said step of actuating includes moving the pistons of the some of the actuators, respectively, between a retracted position and an extended position, respectively, to push the products in the first and second inner and outer longitudinal channel sections, respectively, and alternately moving all except one of the pistons of the others of the actuators, respectively, between a retracted and an extended position, respectively, to push the products in the inner transverse channel section and the first outer transverse channel section simultaneously with moving the one of the pistons of the others of the actuators between an extended position and a retracted position to pull the products in the second outer transverse channel section.
  • 42. A method of irradiating products as recited in claim 41 wherein the irradiator shell is disposed within an enclosure, said step of introducing includes introducing the products through an entry opening in the enclosure communicating with the inlet port of the irradiator shell and said step of discharging includes discharging the products through an exit opening of the enclosure communicating with the outlet port of the irradiator shell.
  • 43. A method of irradiating products as recited in claim 42 wherein said step of introducing includes passively conveying the products along a delivery member extending through the entry opening of the enclosure and having a first end disposed adjacent the inlet port of the irradiator shell and a second end disposed externally of the enclosure and said step of discharging includes passively conveying the products along a discharge member extending through the exit opening of the enclosure and having a first end adjacent the outlet port of the irradiator shell and a second end disposed externally of the enclosure.
  • 44. A method of irradiating products comprising the steps ofmounting an irradiator shell in a transportable enclosure having an entry access opening in communication with an inlet port of the shell and having an exit access opening in communication with an outlet port of the shell; transporting the enclosure to a source of products to be irradiated; coupling a delivery member with the inlet port such that the delivery member extends through the entry access opening with a first end of the delivery member in external alignment with the inlet port and a second end of the delivery member disposed externally of the enclosure; coupling a discharge member with the outlet port such that the discharge member extends through the exit access opening with a first end of the discharge member in external alignment with the outlet port and a second end of the discharge member disposed externally of the enclosure; passively conveying the products to be irradiated in series along the delivery member from the second end to the first end thereof; sequentially moving the products to be irradiated directly from the first end of the delivery member through the inlet port and onto and in contact with a non-moving transport surface within the shell extending continuously and without interruption from the inlet port to the outlet port; moving the products to be irradiated in series relative to and along the non-moving transport surface past an irradiation source within the shell whereby the products are irradiated; sequentially discharging the irradiated products directly from the non-moving transport surface through the outlet port and onto the first end of the discharge member; and passively conveying the irradiated products in series along the discharge member from the first end to the second end thereof.
  • 45. The method of irradiating products recited in claim 44 wherein said step of coupling the delivery member includes coupling a delivery roller ramp with the inlet port, said step of passively conveying the products to be irradiated includes conveying the products to be irradiated along the delivery roller ramp by gravity, said step of coupling the discharge member includes coupling a discharge roller ramp with the outlet port and said step of passively conveying the irradiated products includes conveying the irradiated products along the discharge roller ramp by gravity.
  • 46. The method of irradiating products recited in claim 44 wherein said step of moving includes moving the products through the shell with a major dimension of the products disposed parallel to a plane containing the irradiation source.
  • 47. The method of irradiating products recited in claim 46 wherein said step of passively conveying the products to be irradiated includes passively conveying the products to be irradiated along the delivery member with the major dimension of the products disposed parallel to the plane containing the irradiation source, said step of sequentially moving includes moving the products to be irradiated from the delivery member into the shell with the major dimension of the products disposed parallel to the plane containing the irradiation source, said step of sequentially discharging includes discharging the irradiated products from the shell onto the discharge member with the major dimension of the products disposed parallel to the plane containing the irradiation source and said step of passively conveying the irradiated products includes passively conveying the irradiated products along the discharge member with the major dimension of the products disposed parallel to the plane containing the irradiation source.
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Number Name Date Kind
1876737 Opp Sep 1932 A
3142759 Jefferson et al. Jul 1964 A
3411002 Armel Nov 1968 A
3454761 Brunner Jul 1969 A
3641342 Armel et al. Feb 1972 A
3686502 Sieber Aug 1972 A
4066907 Tetzlaff Jan 1978 A
4864595 Barrett Sep 1989 A
5001352 Tetzlaff Mar 1991 A