Pass through delivery device

Information

  • Patent Grant
  • 6378769
  • Patent Number
    6,378,769
  • Date Filed
    Friday, August 6, 1999
    25 years ago
  • Date Issued
    Tuesday, April 30, 2002
    22 years ago
Abstract
A pass through closure and delivery device permitting material to be safely passed through a slot in a partition or prison cell door. A container having first and second openings and first and second doors associated with each opening is disclosed for mounting on a partition or cell door having a slot therethrough. Each door on the container includes a latch that is operable from only one side of the cell door. A cam-operating attaching mechanism allows the container to be releasably mounted to a pair of track members affixed to the cell door with the slot therebetween. Using the pass through delivery device and the method of the present device, food or other materials can be safely delivered to an inmate inside a locked cell by mounting the container of the pass through delivery device on the cell door with one of the openings adjacent the first door covering the slot in the partition. The second door is then opened, allowing a guard or delivery person to insert a food tray or other materials to be delivered into the container. The second door is then latched shut and the first door is then opened to allow the prisoner access to the food or other materials through the cell door slot and the first opening in the container. After the inmate removes the food or material from the container, the first door is again shut and the container can be removed from the cell door.
Description




BACKGROUND OF THE INVENTION




1. Technical Field




This invention relates generally to the field of pass-through delivery systems, whereby items are passed from one person to another through a structural partition such as a wall or door. More particularly, the present invention relates to an apparatus and method for safely delivering food or other materials to a person confined within a secure room, as might be done when delivering food or mail to a prison inmate through a locked cell door.




2. Background Information




It is a common practice in many prisons and other detention facilities to deliver food or other materials to an inmate while the inmate is confined within a locked room or cell. Typically, the door used on a prison cell is constructed with a small opening or slot through the door, which is usually covered by a hinged panel that can be opened and closed from outside of the cell. A small shelf often extends from the outside of the door near the opening. A prison guard or other employee can pass a food tray or other materials to an inmate inside the locked prison cell by opening the hinged panel from outside the cell and setting the food tray or materials on the shelf. The prisoner inside of the cell can then receive the food or materials through the pass through slot in the door.




Unfortunately, conventional pass through openings of the type described above pose a significant risk to prison guards and other personnel outside the cell when the hinged panel is opened. During such time, an inmate inside the cell may attempt to reach through the pass through opening and grab or strike the guard or delivery person delivering food. An inmate may also attempt to throw objects through the pass through opening or to push the food tray back on to the guard or food delivery person.




In a particularly egregious practice, known among prison personnel as a “gas attack” or “gassing,” some inmates with psychological or behavioral problems attempt to throw, splash, spit, or otherwise project bodily fluids or airborne pathogens at prison staff personnel through the open slot in the cell door during food delivery. With the prevalence of HIV infection among inmates in many prison populations, the ability to protect prison staff personnel from so-called “gas attacks” is increasingly important.




It would therefore be desirable to have in the art a pass through system that is capable of transferring food and other items through a locked cell door or other partition while at the same time effectively protecting prison employees against gas attacks and harmful contact with the recipient inside the cell. Such a pass through system should of course be ruggedly constructed to withstand use in the prison environment and should also be easy and quick to use, so as not to unduly impede the efficient delivery of food or materials to many inmates in large correctional facilities. It would also be advantageous if such a pass through system was capable of being used with existing prison doors and partitions as well as being capable of incorporation in new prison facilities.




BRIEF SUMMARY OF THE INVENTION




The present invention overcomes the drawbacks associated with conventional prison food delivery apparatus by providing a pass through delivery device that permits material to be safely passed through a slot in a partition or cell door. The delivery device has a container with two openings that are closable by first and second doors and the container is adapted for mounting on one side of the partition with one of the openings communicating with the slot in the partition. The first door is mounted for movement between a first position in which the first door is between the partition slot and the container opening that is adjacent the slot and a second position permitting open communication between the partition slot and the container opening. The second door is mounted at the second opening in the container for movement between an open position permitting access to the interior of the container and a closed position closing the second opening.




A latch for selectively maintaining the first door at the first position and a second latch for selectively maintaining the second door at the closed position are positioned to permit access thereto from only one side of the partition. Advantageously, the first and second doors can be operated alternatively by a prison guard or other delivery person located on one side of the partition to pass material through the partition slot without being exposed to the danger of gas attacks or other harmful contact from a person on the other side of the partition because one of the two doors is always closed during the delivery process, thereby preventing the inmate from contacting or throwing objects or fluids at prison employees.




The pass through delivery device may include a pair of track members affixed to the partition with the slot therebetween and the first door may be slidably disposed between the pair of track members. An attaching mechanism may also be affixed to the container for releasably mounting the container to the partition and, advantageously, the attaching mechanism may be a clamping mechanism releasably clamping the container to the pair of track members.




The present invention also provides a kit for mounting a removable pass through delivery device on a partition having a slot therein to permit material to be safely passed through the slot in the partition. The kit includes a pair of track members adapted to be mounted on one side of the partition and a container having first and second openings and adapted to be mounted on the track members with the first opening communicating with the slot in the partition. A first door adapted to be mounted on the track members is provided in the kit for movement between a first position between the slot and the first container opening and a second position permitting open communication between the slot and the first container opening. A latch is provided for mounting adjacent the first door for selectively maintaining the first door at its first position. A second door for mounting at the second container opening is provided for movement between an open position permitting access to the interior of the container and a closed position closing the second opening of the container. A latch is provided to be mounted adjacent the second door for selectively maintaining the second door at its closed position. When the removable pass through delivery device is mounted on the partition, the latches are positioned to permit access thereto from only one side of the partition. The kit may also include a clamping mechanism adapted to be affixed to the container for releasably clamping the container to the pair of track members mounted on one side of the partition.




Material can be safely passed through a slot in a partition or cell door from one side thereof using the method of the present invention. A container with first and second openings and first and second doors for selectively opening and closing the openings is positioned adjacent the partition with its first opening located adjacent the slot in the partition. A guard or delivery person on one side of the partition opens the second door while maintaining the first door in its closed position and places material in the container through the second opening from one side of the partition. After closing the second door, the guard then opens the first door to permit the material to be removed from the container through the first opening by an inmate or person on the other side of the partition. After delivery, the first door can then be closed and the container removed from its position adjacent the partition and stored or used to deliver material to other cells.




Using the pass through delivery device of the present invention, therefore, it is possible to pass food or other material from one side of a cell door to an inmate inside the cell without both of the doors on the device being opened at the same time, thus ensuring the safety of the guard or delivery person. Moreover, the delivery device of the present invention is quick and easy to use and is reusable such that a single delivery device may be used to deliver food to inmates in many different cells. These and other advantages of the present invention will become apparent upon reading the following detailed description and appended claims, and upon reference to the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS




For a more complete understanding of this invention reference should now be had to the embodiments illustrated in greater detail in the accompanying drawings and described below. In the drawings, which are not necessarily to scale:





FIG. 1

is a perspective view of a pass through delivery device according to one embodiment of the present invention affixed to a cell door;





FIG. 1



a


is a perspective view of a latch for use on the second door of the pass through delivery device;





FIG. 2

is a perspective view of the first door and surrounding structure according to one embodiment of the present invention;





FIG. 2



b


is a perspective view of a latch for use on the first door of the pass through delivery device;





FIG. 3

is an elevation view of a container and clamping device according to one embodiment of the present invention, taken along the


3





3


line in

FIG. 1

; and





FIG. 4



a-




4




h


are side elevation views of a pass through delivery device according to one embodiment of the present invention, with the cell door and track members shown partially in section, illustrating a method of delivering a food tray through a cell door.











DETAILED DESCRIPTION OF THE INVENTION




The present invention will now be described fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It will be understood that all alternatives, modifications, and equivalents are intended be included within the spirit and scope of the invention as defined by the appended claims.




Turning now to

FIGS. 1 and 2

, there is shown a pass through delivery device


10


for permitting material to be safely passed through a slot in a partition or cell door


11


. The pass through device comprises a container


15


, first and second doors,


20


,


35


, and first and second latches


21


,


38


. The container


15


has a first opening


14


(see

FIG. 4



a


) and a second opening


16


(see

FIGS. 4



d,




4




f


) and may be fabricated from any suitable material that is rugged and yet lightweight. A particularly suitable material is ⅛ inch thick aluminum sheet metal. The container may be equipped with handles


30


to assist in mounting the container


15


to the partition or cell door


11


. The pass through delivery device may also include an attaching mechanism


55


for releasably attaching the container


15


to the cell door


11


and a particularly advantageous attaching mechanism is discussed in more detail below.




As shown in

FIG. 1

, the second door


35


is mounted at the second opening of the container


15


and, advantageously, a continuous stainless steel hinge


37


may be used to mount the second door


35


to the container


15


. The second door is movable between a closed position (as illustrated in

FIG. 1

) in which the second door


35


closes the second end of the container and an open position (illustrated in

FIG. 4



e


) in which access is permitted to the interior


17


of the container. While the container


15


may be fabricated in any suitable size and cross-sectional shape, in a preferred embodiment the container


15


has a rectangular cross-sectional shape and is sized to accommodate a standard inmate feeding tray in the interior


17


of the container. A flange


36


may also be provided on the second door


35


.




A second latch


38


is used to selectively maintain the second door


35


in the closed position and a suitable catch for use as a second latch


38


is illustrated in

FIG. 1



a


. The second latch


38


includes a catch mechanism


40


affixed to the container


15


and an associated latching post


39


affixed to the second door


35


. A release


41


on the catch mechanism


40


securely holds the latching post


39


in place when the second door


35


is in the closed position. When it is desired to move the second door


35


to its open position, a guard or other delivery person may move the release


41


laterally in the catch mechanism


40


, grasp the latching post


39


and move the second door


35


to its open position. A hole may be provided in the release


41


for the provision of a padlock


29


if it is desired to lock the second door


35


in the closed position. It should be understood, however, that the second latch


38


is capable of maintaining the second door


35


in the closed position without using a padlock


29


.




The container


15


is adapted for mounting on one side of the partition


11


and, when properly mounted thereon, the first opening


14


in the container


15


is adjacent a slot


12


in the partition and the communication is established between the slot


12


and the first opening


14


. A first door


20


is mounted to be movable between a first position in which the first door


20


is between the slot


12


in the partition and the first opening


14


in the container


15


and a second position permitting communication between the partition slot


12


and the first opening


14


.





FIG. 2

illustrates an advantageous mounting of the first door


20


onto a partition or cell door


11


. A pair of track members


50


are affixed by a suitable method, such as welding, to the partition


11


with the slot


12


therebetween and the first door


20


is slidably disposed between the pair of track members in channels


52


formed between the track members and the partition. In this arrangement, the first door


20


is movable between a first position adjacent and covering the slot


12


and a second position exposing the slot


12


and allowing communication between the slot


12


and the first opening


14


in the container. One of the track members


50


includes a guide track


53


, a notch


25


and a pair of stops


51


to prevent over extension of the first door past the first or second positions. The track members and the slot may be fabricated from any suitable material; however, 7 gauge steel is a particularly suitable material to use in fabricating the T-shaped guides and the first door. An optional shelf


18


may be provided on a track member or, alternatively, on the partition


11


. When present, the shelf


18


is generally positioned below the slot


12


in the partition


11


and the position of the shelf may be adjustable.




A first latch


21


allows for selectively maintaining the first door


20


at its first position and a suitable latch for use as a first latch mechanism is illustrated in

FIG. 2



b.


The first latch mechanism


21


includes a lock guide


24


, a square bar


22


, and a bar handle


23


. The first latch


21


is positioned on the first door


20


such that the square bar


22


is positioned within the notch


25


when the first door


20


is in its first position. In this position, the square bar


22


is disposed between the guide track


53


and one of the stops


51


to prevent the first door


20


from moving out of its first position.




When it is desired to move the first door


20


to its second position, a guard may use the bar handle


23


to move the square bar within the lock guide


24


to a position in which the bar is clear of the guide track


53


, thereby free to slide within the channels


52


of the pair of track members. As illustrated in

FIG. 2



b,


a hole may be provided in the square bar


23


for the provision of a padlock


29


if it is ever desired to lock the first door


20


in its first position. It should be noted, however, that the first latch


21


is capable of maintaining the first door


20


in its first position, as described above, without using the padlock


29


. Also, the first latch


21


may be advantageously positioned in a vertical orientation such that gravity will ensure that the square bar


22


falls into the notch


25


when the first door


20


is moved to its first position. The square bar may be made from any suitable material, but a particularly suitable material is ½ inch square steel.




While the container


15


of the present invention may be permanently or semi-permanently mounted on the partition or cell door


11


, it is advantageous to equip the container


15


with a suitable attaching mechanism to thereby allow the container to be releasably mounted on the cell door. In this way, a single container


15


can be used to deliver food to many different inmates in many different cells. Those skilled in the art will recognize that a variety of different releasable attaching mechanisms may be used to releasably attach the container


15


to the partition


11


—such as, for example, sliding the container onto tracks affixed to the partition; equipping the partition with extending posts that cooperate with mounting apertures on the container, or using quick release bolts or fittings to mount the container onto the partition—but a particularly advantageous attaching mechanism is a clamping mechanism illustrated in FIG.


3


.





FIG. 3

is a plan view of the container


15


, taken along the viewing line


3





3


in FIG.


1


. In this view, the interior


17


of the container


15


is visible as well as an open cavity


19


defined by the container


15


. Because the pass through device of the present invention may be installed on existing prison cell doors, many of which have a shelf


18


extending outwardly therefrom, provision is made in the container for an open cavity


19


to receive the preexisting shelf without interfering with the operation of the pass through delivery device. When the device is mounted on such an existing cell door, the shelf


18


is received in the open cavity


19


. Also visible in

FIG. 3

is a weld seam


26


which may be provided in fabricating the container


15


at the junction of container sides to increase the structural integrity of the container and assist in maintaining sanitation of the container by filling in cracks or gaps at the junction in which food or harmful bacteria or viruses may be located.




With regard to the sanitation, it should be noted that closable ports (not shown) extending through the container walls may be provided to provide an opening through which an antibacterial agent or other disinfecting agent can be introduced if desired to disinfect the interior of the container. For example, disinfecting spray may be introduced into the interior of the cavity after delivering food to an inmate, and while the first and second doors are in the first and closed positions, respectively, to disinfect the container before using the container to deliver food to another inmate.




The attaching mechanism


55


is preferably a clamping mechanism including two opposed latch hooks


62


that engage channels


52


of the track members


50


(as shown in

FIGS. 4



b-




4




h


). One of the latch hooks


62


is adjustably connected to a latch tray


61


, which is pivotably mounted to the container


15


and made to pivot by operation of a cam


56


through adjustable linkages


58


. The cam


56


is secured to the container


15


by a cam mount


57


and is made to operate by an operating handle


60


. A support bar


59


may extend between the cams if desired.




Operation of the clamping mechanism is shown in

FIGS. 4



a-




4




h,


which also illustrate a method of safely passing material through a slot


12


in a partition or cell door


11


. To deliver food or other materials to a prison inmate using the pass through delivery device of the present invention, the container


15


is first positioned adjacent the partition


11


with the first opening


14


of the container adjacent the slot


12


in the partition. The first door


20


is in its first position and therefore communication is prevented between the slot


12


and the first opening


14


of the container


15


, as shown in

FIG. 4



a.


As illustrated in

FIG. 4



b,


the container


15


is initially “hung” on one of the track members


50


by inserting one of the latch hooks


62


in the channel


52


of one of the track member


50


.




As illustrated in

FIG. 4



c,


after “hanging” the container


15


on one of the track members


50


, a guard or delivery person using the operating handle


60


can then move the cam


56


away from the partition or cell door


11


to thereby cause the latch hook


62


attached to the latch tray


61


to engage a channel


52


of the other track member, thereby securing the container


15


to the partition


11


by clamping action against the pair of track members. The shape of the cam


56


ensures that when the clamping mechanism is fully engaged, there is a space between the operating handle


60


and the container


15


to prevent a guard or delivery person from smashing his or her fingers between the operating handle


60


and the container


15


when moving the cam


56


. Once clamped, the container is securely affixed to the partition and cannot be moved by an inmate inside the prison cell.




Once the container


15


is securely positioned adjacent the partition such that the first opening


14


is adjacent the slot


12


in the partition


11


, a guard or delivery person wishing to pass materials to an inmate inside the cell can then open the second door


35


, as illustrated in

FIG. 4



d.


Once the second door


35


is moved to its open position, which is illustrated in

FIG. 4



e,


items to be delivered through the partition such as a food tray


13


may be placed in the container


15


through the second opening


16


of the container


15


. Once the items to be delivered


13


are within the interior


17


of the container, the guard or delivery person then moves the second door


35


to its closed position, as illustrated in

FIG. 4



f.






As illustrated in

FIG. 4



g,


once the second door


35


is latched in its closed position, the first door


20


can be moved or slid to its second position, wherein communication is established between the slot


12


in the partition


11


and the first opening


14


in the container. As illustrated in

FIG. 4



h,


an inmate inside the cell can then remove the items to be delivered


13


from the container


15


through the slot


12


. After verifying that the items to be delivered have been removed from the container, which can be done using a conventional cell door viewing window, the guard can then move the first door


20


back to its first position to thereby close the slot


12


and the container


15


can be removed by reversing the mounting steps described above.




As shown by the above discussion, the present pass through delivery device uses a container and two doors to allow pass through delivery of materials while at the same time isolating an inmate inside the cell from contact with guards or delivery personnel outside the cell. This isolation is achieved using a container that can be releasably but securely affixed to the partition and using first and second latch mechanisms that are only operable from one side of the cell door—the outside. Thus, when the first door covering the slot is open, the prisoner cannot throw items or splash bodily fluids onto the guard or delivery person nor can the prisoner defeat the pass through delivery device by knocking it off of the partition. After delivering the materials, a guard can move the first door to its first position and the first door will remain latched in this position even after the pass through delivery device is removed.




It will readily be understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those specifically described herein, as well as many variations, modifications, and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing descriptions thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for the purpose of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications or equivalent arrangements; the present invention being limited only by the claims appended hereto and the equivalents thereof. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for the purpose of limitation.



Claims
  • 1. A pass through delivery device in combination with a partition and which permits material to be safely passed from a first side of the partition to a second side of the partition through a slot in the partition, said device comprising:a container having first and second openings and being mounted on a pair of track members affixed to said first side of the partition with the slot therebetween and said first door slidably disposed between said pair of track members with the first opening communicating with the slot in the partition; a first door mounted on said first side of the partition for movement between a first position between the partition slot and the first opening of said container and a second position permitting open communication between the partition slot and the first opening of said container; a first latch for selectively maintaining said first door at the first position thereof, said first latch being positioned on said first side of the partition to permit access thereto from only one side of the partition; a second door mounted at the second opening of said container for movement between an open position permitting access to the interior of said container and a closed position closing the second opening of said container; and a second latch for selectively maintaining said second door at the closed position, said second latch being positioned to permit access thereto from only one side of the partition, whereby said first and second doors can be accessed and operated only by an operator located on said first side of the partition so that the first and second doors can be operated alternatively by the operator to pass material through the partition slot without the operator being exposed to said second side of the partition.
  • 2. A combination as defined in claim 1, further comprising an attaching mechanism for releasably mounting said container to the partition.
  • 3. A combination as defined in claim 2, wherein said attaching mechanism comprises a clamping mechanism mounted on said container releasably clamping said container to said pair of track members.
  • 4. A combination as defined in claim 1, wherein said second door is mounted at the second opening of said container by a hinge.
  • 5. A combination as defined in claim 1, wherein the cross-sectional shape of said container is substantially rectangular.
  • 6. A pass through closure for a prison cell that permits material to be safely passed to a person inside the cell, said closure comprising:a cell door having a first side, a second side and a slot therethrough; a container having first and second openings and being adapted for mounting on said first side of the cell door with the first opening communicating with the slot in said cell door; a first door mounted on said first side of said cell door for movement between a first position between the slot in said cell door and the first opening of said container and a second position permitting open communication between the cell door slot and the first opening of said container; a first latch for selectively maintaining said first door at the first position thereof, said first latch being positioned on said first side of said cell door to permit access thereto from only said first side of said cell door; a second door mounted at the second opening of said container for movement between an open position permitting access to the interior of said container and a closed position closing the second opening of said container; and a second latch for selectively maintaining said second door at the closed position, said second latch being positioned to permit access thereto from only said first side of said cell door, whereby said first and second doors can be accessed and operated only by an operator located on said first side of said cell door so that said first and second doors can be operated alternatively by the operator to pass material through the cell door slot without the operator being exposed to said second side of said cell door.
  • 7. A pass through closure as defined in claim 6, further comprising a pair of track members affixed to said cell door with the slot therebetween and wherein said first door is slidably disposed between said pair of track members.
  • 8. A pass through closure as defined in claim 7, further comprising an attaching mechanism for releasably mounting said container to said cell door.
  • 9. A pass through closure as defined in claim 8, wherein said attaching mechanism comprises a clamping mechanism mounted on said container releasably clamping said container to said pair of track members.
  • 10. A pass through closure as defined in claim 6, wherein said second door is mounted at the second opening of said container by a hinge.
  • 11. A pass through closure as defined in claim 6, wherein the cross sectional shape of said container is substantially rectangular.
  • 12. A kit for mounting a removable pass through delivery device on a partition having a slot therethrough that permits material to be safely passed though the slot in the partition, said kit comprising:a pair of track members adapted to be mounted on one side of the partition; a container having first and second openings and adapted to be mounted on said track members with the first opening communicating with the slot in the partition; a first door adapted to be mounted on said track members for movement between a first position between the partition slot and the first opening of said container and a second position permitting open communication between the partition slot and the first opening of said container; a first latch adapted to be mounted adjacent said first door for selectively maintaining said first door at the first position thereof, said first latch being positioned to permit access thereto from only one side of the partition when the removable pass through delivery device is mounted on the partition; a second door adapted to be mounted at the second opening of said container for movement between an open position permitting access to the interior of said container and a closed position closing the second opening of said container; and a second latch adapted to be mounted adjacent said second door for selectively maintaining said second door at the closed position, said second latch being positioned to permit access thereto from only one side of said partition when the removable pass through delivery device is mounted on the partition, whereby when the removable pass through delivery device is mounted on the partition said first and second doors can be operated alternatively by an operator located on one side of the partition to pass material through the partition slot without being exposed to the other side of the partition.
  • 13. A kit for mounting a removable pass through delivery device on a partition as defined in claim 12, further comprising a clamping mechanism adapted to be affixed to said container for releasably clamping said container to said pair of track members when said pair of track members is mounted on one side of the partition.
  • 14. A method of safely passing material from a first side of a partition to a second side of the partition through a slot in the partition from said first side thereof, comprising the steps of:providing a container having first and second openings and first and second doors for selectively opening and closing the openings, respectively; positioning the container adjacent to and on said first side of the partition with the first opening located adjacent the slot in the partition; opening the second door while maintaining the first door in its closed position and placing material in the container through the second opening from said first side of the partition; and closing the second door and then opening the first door from a position on said first side of the partition to permit the material to be removed from the container through the first opening from said second side of the partition, whereby an operator located on said first side of the partition can pass the material from said first side of the partition to said second side thereof without both of the doors being opened at the same time and without the operator being exposed to said second side of the partition while passing material.
  • 15. A method of safely passing material through a slot in a partition as defined in claim 14, comprising the additional step of moving the first door to close the first opening in the container after the material has been passed from said first side of the partition to said second side thereof.
  • 16. A method of safely passing material through a slot in a partition as defined in claim 15, comprising the final step of removing the container from the position adjacent the partition.
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