1. Field of the Invention
This invention relates generally to an apparatus, system and method of ionized air rinsing of containers, and more specifically to the rinsing of such containers without use of water, brushes or other elements that come into direct contact with the containers.
2. Background Art
Empty containers, such as PET bottles, intended for filling with a liquid beverage typically become contaminated with foreign material, such as paper and wood dust, during shipping, even when they are stored in boxes or other carrying receptacles and also as they are being processed prior to filling. In the latter case, contact between the containers and the surfaces of articles, such as conveyors or carriers, used to convey the containers, cause them to pick up a small amount of net electrostatic charge, thereby rendering them capable of attracting fine particles to the containers' internal and external walls. Thus, the need to rinse or otherwise clean the containers prior to filling is necessary to ensure that the beverages are acceptable to the ultimate consumer.
The dust particles contaminating these containers are characteristically extremely small, often measuring less than 10 microns in diameter. Any electrostatic charges on the containers induce opposite charges on the particles to attract and hold them on the containers' walls. To remove particles adhering to the walls, these opposite charges must be neutralized. Neutralizing the charges is difficult, however, because the charges holding each dust particle to a container's wall are shielded by the dust particle itself. Moreover, once the electrostatic forces have been momentarily abated, the freed dust particles must be removed immediately before they re-attach themselves to a container.
Several methods have been used to provide a thorough cleaning of the inside of a bottle. In the prior art methods, the processing of empty containers in preparation for filling them with beverages and the like included spraying the containers with water. This cleaning technique, however, fails to remove all of the dust particles inside the containers unless extraordinary measures are taken. Moreover, the high humidity generated by the water sprays favors the growth and spread of microorganisms, creating additional problems in the typical factory environment.
Other methods utilize a hot water rinse directed into a bottle having a downwardly facing opening, wherein a large number of bottles are being transported through a conveyor system at a high rate of speed. An example of such a cleaning arrangement is disclosed in U.S. Pat. No. 5,363,866. A jet nozzle arrangement is taught which provides an aeration and distribution of a cleaning agent at successive stations in the conveyor line.
The use of hot water or chemical disinfectants typically has been considered unsuitable for rinsing PET bottles prior to filling because hot water or disinfectants may chemically or physically alter the characteristics of PET bottle material. Such alterations could render the bottles unsuitable for containing beverages, or may adversely affect the quality or taste of the beverage, or may even render the beverage unsuitable for human consumption.
Various devices and processes not using unsuitable chemicals or excessively hot water have been proposed for sanitizing containers such as bottles. For example, devices using ozone or ozonated water as a sanitizing agent have been proposed. Ozone is highly reactive and is an effective oxidizing agent for sanitizing containers. Ozonated rinse water is preferable to untreated rinse water because it may be effective in removing microbes and other contaminants without changing the chemical or physical nature of the container. For example, Silberzahn U.S. Pat. No. 4,409,188 proposes a device for sterilizing containers that comprises a rotatable immersion wheel for immersing the containers in a bath of ozone and water. Hughes U.S. Pat. No. 5,106,495 proposes a portable water purification device using ozone as a treatment agent circulated by a pump through a venturi where the ozone is injected into the water, which is then returned to the tank after cleaning. However, the use of water or other liquid rinse media slows the rinsing process as a result of the need to dry or otherwise remove the liquid from the container prior to filling, which takes time and slows down the container preparation and filling procedure.
Another consideration of those prior art methods and systems that have a fluid or jet stream that is directed into the container, and especially those which intrude thereinto by inserting a nozzle or other means of producing a jet flow into the enclosure of the container itself, is that there is a possibility for introduction of extraneous matter and/or contamination into the bottle, which presently requires measures to avoid the possibility of such contamination. Additionally, methods which require the insertion of a nozzle into a container complicate and slow the cleaning process, because the container must be aligned fairly precisely with the nozzle and held in position for some period of time.
Other methods for cleaning containers of dust and debris, and more specifically, cleaning of plastic or PET bottles, are known, but most of these are similar to those prior art methods and systems described above. Ionized gas streams injected into upside down containers are taught in U.S. Pat. No. 4,208,761 to Ionescu and U.S. Pat. No. 5,265,298 to Young. The latter patent teaches a series of ionized nozzles staggered with intervening vacuum collectors to enable capture of ionized dust particles immediately after they have been “loosened” from the internal surface of a container. It should be noted that the ionized nozzles are expensive, and a configuration having only ionized nozzles in a long container cleaning station will cause the complete container cleaning system to be overly expensive. In addition, U.S. Pat. No. 5,265,298 does not have any type of guard or means to maintain a clearance between the nozzles and the fast moving containers that are sped past on guard rails. Accordingly, it becomes possible that misalignment of the elements of the system may cause the displacement of one or more nozzles such that a container that is skewed may collide with the nozzle at a high rate of speed, thus causing damage not only to the container but perhaps also to the nozzle, and shutting down the container processing line for repairs for a considerable period.
What is needed is a cleaning procedure that is efficient, effective, relatively inexpensive and does not produce undesirable effluents or other residual elements, such as rinse water residue, while simultaneously providing resource conservation and sustainability. A configuration that protects the sensitive elements of the system is also desirable to reduce down time and expensive replacement parts of the system.
The present invention is directed to an improved container cleaning apparatus and method for cleaning, without the use of water sprays, open-topped containers such as bottles as they travel along an assembly line. The containers preferably enter the apparatus in an upside down position and are carried in an essentially horizontal direction through an enclosure or housing as they are transported through the system. The containers may be conveyed through the apparatus on a moving belt, preferably having inwardly extending fingers.
The apparatus further includes one or more cleaning stations disposed within the housing and positioned immediately below the bottle flow path, with the highest points of each cleaning station being disposed slightly downwardly of an imaginary plane through which the openings of the bottles traverse. Each cleaning station comprises an ionized air injector with a series of nozzles and a second series of high velocity nozzles downstream from the ionized air nozzles, which provide turbulent air flow that ejects the dust particles from the inside of the containers and from the immediate vicinity of the containers.
As the containers are transported through the housing, an ionized air stream is directed from the ionizing nozzles into each empty container to dislodge any dust particles there and to neutralize electrostatic charges on the particles and the container walls. Suction from the vacuum inlet, a pan or slot situated immediately below the conveyor and ionized gas nozzles through which the ionized air flow is injected, removes dislodged dust particles. Dust removal with the apparatus is enhanced when the vacuum pan or slot is located beneath the ionizing nozzles at the front or entrance end of the longitudinal axis of the bottle flow path. Greater turbulence increases the likelihood that a dust particle, once it has been suspended in these air flows, will be removed from the container altogether, improving cleaning efficiency.
When more than one set of cleaning nozzles is employed in a cleaning system according to the present invention, the nozzles are preferably deployed in close proximity to each other. Such an arrangement of the nozzles takes advantage of the dislodgement of dust particles occurring as a result of the containers being subjected first to the air stream of the ionized gas nozzles and then to the high velocity air nozzles as the air flows through the interior of the containers at successive cleaning stations disposed immediately upstream of each other.
To prevent recontamination of the containers by their exposure to the dust particles floating in the air, the enclosure is preferably pressurized with filtered air from the nozzles, using a blower with an inlet filter, and evacuated of the dusty air by a vacuum blower that immediately evacuates any air in the housing before the dust particles can adhere to the container surfaces.
Accordingly, there is provided a waterless, brushless apparatus for removing dust particles from empty containers while they move forwardly in a line along a predetermined container flow path, each container having at least one open side, the open side facing in a generally common direction with the open side of each of the containers contiguous with said container, comprising an open-ended housing, the predetermined container flow path traversing the enclosure longitudinally in the direction of forward movement in the container flow path, a first set of ionizing air nozzles mounted within the housing, the ionizing air nozzles adapted for directing ionized compressed air toward the container flow path, the nozzles being oriented to direct air flow generally perpendicularly to the direction of forward motion of the containers along the predetermined ionizing air nozzles, so that ionized compressed air directed from at least one of the nozzles flows into the open side of each container as it passes the nozzle; and a second set of high velocity air nozzles mounted within the housing, the high velocity air nozzles adapted for directing high velocity compressed air toward the container flow path, the second set of high velocity nozzles being disposed along a direction essentially parallel to the container flow path with the nozzle openings being oriented generally perpendicularly to the direction of forward motion of the containers along the predetermined flow path, so that high velocity compressed air directed from at least one of the nozzles flows into the open side of each container as it passes the nozzle.
Also disclosed and claimed is a method of air rinsing containers by passing through a waterless, brushless air rinsing system comprising providing an air rinsing apparatus having a first set of ionizing air nozzles and a second set of high velocity air nozzles, and a vacuum source for evacuating the air around the containers, passing, at a high rate of speed, plural containers having a downwardly facing open side over the air streams emitted from the nozzles, and
evacuating the air and any entrained foreign particles from the immediate environment of the containers by the suction provided by the vacuum source.
Referring now to the figures, in which like corresponding reference numerals are used to designate like or corresponding parts throughout the several views, a preferred embodiment of the inventive air rinsing apparatus is shown.
A part of a container cleaning system 10 according to the present invention is shown in
The system 10 includes additional elements, which are not shown. These are for the most part conventional and will be known to those of ordinary skill in the art. Those elements shown in
The conveyor arrangement 12 transfers the bottles 40 so the bottle flow path follows the direction of the arrows, and as a result of the bottle path passing around a large pulley rotating wheel 14, the bottles become inverted in a generally upside down position with the opening being downwardly directed, as shown by bottle 40 in
The other elements that are shown in
The air cleaning system 20 is essentially enclosed by housing 22 providing an enclosure to maintain substantial equilibrium of air flow within the system 20. Of course, two openings, one of which is shown in
Referring now to
The manifold 24 includes attachment points for the additional elements of the system 20, including a series of spaced threaded outlet holes 26, to which the pipes 28, attached to different air nozzles, are threadably attached. Ideally, the threaded attachments of pipes 28 to the manifold 24 are air tight, to ensure essentially complete pressurized air flow through each of the nozzles. Various nozzle attachments may be provided for particular applications.
Referring now to
The deflector guard 30 provides protection from the possibility that the bottle position of bottles 40 may have been skewed in the previous processing and the bottle opening may not be in the desirable vertical position relative to the tops of the nozzles. That is, as the bottles 40 travel through the station 20, they should be at or near a desirable vertical position and orientation, as they are gripped by the gripping fingers 39. If the vertical position has been displaced, so that in the upside down position the bottle opening 41 is too low, it may push or bump one or more of the nozzles that the bottle opening 41 initially encounters on the bottle path. Thus, the deflector guard 30 is disposed in a position prior to the first nozzle in the bottle path to reposition and orient each bottle in the bottle path upon entry to a desired position so as to avoid contact with any nozzle.
The bottle deflector guard 30 comprises a pair of adjustable supports 36 that are adjustably attached at one end of the longitudinally extending manifold 24 by set screws 35. Loosening of set screws 35 allows for the vertical adjustment of the deflector guard 30 so that the bottle openings are consistently at a desired vertical height relative to the top surface of the manifold, and consequently to the top portions of the nozzles. The deflector guard 30 further comprises two sections. A first horizontal section 37 that is essentially parallel to the longitudinal axis of the manifold 24 and is disposed at the vertical height above the manifold 24 to provide sufficient clearance to all of the nozzles in the bottle flow path. A second deflector section 38 is angled to provide a guiding force to the bottle opening 41 to push the bottle 40 up into the desired position in the retaining finger 39 of the conveying apparatus. The bottle 40 is carried by the conveying apparatus along the bottle path in the direction of the arrow, essentially along a line parallel to the longitudinal axis of the air manifold 24. If the bottle 40 is in the proper position, the bottle passes the deflector 30 without making contact. Otherwise, the bottle opening 41 impinges on the angled section 38 which because of the forward momentum of the bottle 40, pushes the opening 41 and the bottle 40 upwardly so that a clearance C is established between the highest point of the nozzles and the opening 41. The clearance C thus initially protects against any undesirable contact or impact between the bottles 40, which are moving at high speed, and the sensitive air nozzles, which can be damaged as a result of such impact.
Referring now to
As shown in
The ionized air is then passed over the external surface of the bottle 40 and into the bottle opening to provide ionized air that detaches any dust or other loose particles from the inner and outer walls of the bottle 40. Ionizing nozzles 60 that are available for use with the bottle cleaning apparatus 20 can be obtained commercially from the Simco Industrial Static Control Division of the Simco Company, Inc., Hatfield, Pa.
As is illustrated in
The remaining, preferably three nozzles, are oriented so that the longitudinal dimension of the nozzle 60 is parallel to the bottle flow path, thus providing the maximum amount of dwell time of the bottle opening 41 within the ionized air stream. This orientation thus directs the maximum amount of ionized air into the bottle interior so as to provide as much ionizing function as possible to the internal bottle surface, thereby ionizing and displacing essentially all of the dust particles from the internal surface. The displaced ionized dust particles float in the environment, and must be removed from the vicinity of the bottles 40.
Although four ionizing nozzles including one laterally oriented nozzle are described as comprising the preferred embodiment, other arrangements are also possible with more or fewer ionizing nozzles and with additional laterally oriented nozzles substituting for the arrangement illustrated.
To provide for the removal of the dust particles, the bottles 40 are then passed over the other types of nozzles, that is, the high velocity air nozzles 80, which are connected to each vertical pipe 28 by a threaded connection 82. The high velocity air nozzles 80 have a constriction to their outlets so that the opening 84 concentrates the pressurized air flow into a smaller jet stream that is directed into the bottle openings 41. The air pressure going into the pipe and nozzle 80 is at about the same pressure as the ionizing nozzles 60, that is, about 40-70 psi, but the air stream flow that is directed into the opening is at an increased velocity and pressure because of the concentration resulting from the constricted opening 84. With the bottles 40 traversing the area of each nozzle at a high rate of speed, the high velocity nozzles provide about 0.5-0.75 seconds of air contact time of the filtered compressed air. The high velocity air nozzles 80 thus are capable of injecting the high pressure air directly into the bottle opening 41 to circulate the air with a high degree of turbulence and at a high rate of speed within the bottle interior. This air circulation is provided almost immediately following the air ionization by the nozzles 60, 60′, when the ionized particles are still essentially suspended in the air within or outside of the bottles 40. Thus, the injected air stream blows the suspended ionized particles out from the bottle interior and away from the opening 41. Ideally, the dwell time that any one bottle spends in the housing 22 is on the order of between 0.75 to 1.5 seconds, and the time each bottle is in contact with the ionized air from the ionizing nozzles 60, 60′ is about 0.25 to 0.5 seconds, and because of the grater number of the high velocity nozzles 80, the time in contact with the air streams for the high velocity nozzles 80 is about between 0.5 to 0.75 seconds.
Referring now to
The vacuum duct 104 is itself connected to the duct 19 (
As is best seen in
To further guard against the bottle openings 41 coming into contact with the sensitive nozzles 60, 60′, and 80, there is disposed a nozzle guard 120 as shown in
The nozzle guard includes several througholes 124 displaced from the centerline CL by a short distance for connecting the nozzle guard 120, by means of, for example, a bolt-nut combination 126 (
Referring again to the nozzle guard 120, as shown in
Additional apertures 132, also matching the expected ionized gas streams that are emitted by the other, preferably three, ionizing nozzles 60 are disposed in line along the centerline CL and also straddling across the fold line 122. However, the longitudinal orientation of the rectangular apertures 132 is with the longer sides in a direction parallel to the centerline CL, thus matching the air stream flow of the ionizing nozzles 60. The apertures 130, 132 are equally spaced apart, matching the spacing of the ionizing nozzle 60′,60, and as shown in
Another set of apertures 134 are disposed through the body of the nozzle guard 120 to provide egress for the air streams of the high velocity nozzles 80 (
The apertures 134 are similarly spaced an equidistant length along the center line CL, but also include a second set of apertures 134′ that are between any two adjacent apertures 134 downstream of a first set of central apertures 134. These second set of apertures 134′, shown to not have an associated nozzle in
Referring now to
Another feature that was discussed briefly above, that of the adjustability of the vertical position of the system 20, will be described in greater detail with reference to
As can be seen in the partial cutaway view of
Rotation of the adjusting bolt 206 raises or lowers the vertical height of the mounting block 200 to a desired position, at which position tightening of the mounting bracket bolts 210 fixes the relative height of the mounting block 200, and all of the cleaning system elements that are attached thereto. Thus, by slight adjustments to the adjusting bolts 206, the clearance C may be optimized for a particular size container 40. Grosser adjustments of the adjusting bolt 206 can modify the clearance C so that the cleaning system 20 may accommodate different size, i.e., smaller bottles, and shape, i.e., opening 41, for different sized and shaped containers (not shown), which can then be cleaned prior to the filling operation which may commence as soon as the bottle processing equipment returns the container 40 to its proper orientation with the opening 41 at the top (not shown in
Referring now to
The configuration 220 shown in
Of course, and as implied by the alternative nozzle configuration 220, other configurations are possible. For example, a fewer or greater number or relative ratio of the types of nozzles 60′, 60 and 80 may be used to achieve varying desirable effects. For example, bottles having a smaller opening 41 may require more high velocity air streams from nozzles 80 to completely evacuate all the dust particles in a bottle of that shape. Other configurations, and changes, modifications and alterations may be made to the systems 20,220, which have been illustrated and described merely as examples and preferred embodiments of the desirable system.
It is apparent from the foregoing that a new and improved method and apparatus for waterless cleaning of containers has been provided. While only the presently preferred embodiment and an alternative nozzle configuration of the invention have been described in detail, as will be apparent to those familiar with the art, certain changes and modifications to the system and method for cleaning containers may be made without departing from the scope of the invention. Accordingly, the specific embodiments illustrated and described herein are for illustrative purposes only and the invention is not limited except as defined by the following claims.
Number | Name | Date | Kind |
---|---|---|---|
1445899 | McGregor | Feb 1923 | A |
2813754 | Zielinski | Nov 1957 | A |
2980938 | Whelan | Apr 1961 | A |
4208761 | Ionescu | Jun 1980 | A |
4313767 | Bemis et al. | Feb 1982 | A |
4962871 | Reeves | Oct 1990 | A |
5265298 | Young | Nov 1993 | A |
5881429 | Drewitz | Mar 1999 | A |
Number | Date | Country | |
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20070240784 A1 | Oct 2007 | US |