Tray loader

A method of loading a tray with at least one layer of items includes forming a plurality items into a group of items, moving the first group in a first generally horizontal direction so that the items are received through a top opening of the tray to form a layer of items that at least partially covers the upper surface of said base. The method also includes moving the tray loaded with the group of items in a generally vertical direction. The vertical direction may be downward. The tray may then be moved again in a horizontal direction. Also a system is provided to perform the aforesaid method.

FIELD OF THE INVENTION

The present invention relates to the loading of trays with one or more layers of items.

BACKGROUND OF THE INVENTION

It is desirable in the packaging industry to be able to load several items as a layer of items into a tray having a top opening (i.e. items can be loaded from above downwards onto the base of the tray to provide a layer of items that at least partially cover the upper surface of the base). It is also desirable to be able to load the tray with more than one layer of such items.

For example, in the food industry, it is well known to have a tray having multiple layers of cookies, each layer comprising several cookies.

To be able to facilitate the loading of the trays, several items are typically first accumulated together into a group and then loaded as a group into an open topped tray.

A known method of loading such trays provides a tray moving in a longitudinal direction on a tray conveyor brought into an adjacent position relative to an item loading conveyor also moving in the same longitudinal direction. If a tray is brought into close proximity to the group of items, the items can be transferred transversely from the moving item loading conveyor into the moving tray carried by the tray conveyor. One difficulty with this type of loading is that if the item conveyor and the carton conveyor continue to move at the same speed in the same horizontal and longitudinal direction, when the items are discharged into the tray transversely they will also move to some degree vertically as they enter the tray from above. Due to the combined transverse, longitudinal and vertical movement, items have a tendency to become improperly oriented when they reach the tray.

One known improved system for loading a tray, is to bring the trays carried on the tray conveyor to a stationary position for loading. The tray can then be loaded while stationary and then be moved again longitudinally by the tray conveyor once the loading has taken place. However, a problem with this method is that if reasonably fast speeds are maintained, to provide a high rate of tray loading, there is a significant acceleration of the tray out of the loading station once the tray has been filled. Depending upon the type of items involved, this can result in the items becoming improperly configured in the tray itself. Thus, this type of system has limits in terms of the type of items that can be loaded in this way and in terms of the maximum speeds and accelerations that can be imparted upon the loaded trays.

It is also known to employ robots having robot arms with end effectors configured for picking up several items at once and then placing them into trays. However, there is a limit to the speed at which robot arms can move. Also they are a relatively complex and expensive solution.

Accordingly, it is desirable to have an improved method and apparatus for loading trays having open tops with a plurality of items.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, there is provided a method of loading a tray with at least one layer of items comprising the steps of forming a plurality of items into a first group of items; moving the first group in a first generally longitudinal horizontal direction; moving the first group in a first generally transverse horizontal direction into a tray; and moving the tray loaded with the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading first, second and third trays each with at least one layer of items. The trays are generally longitudinally aligned in series. The method comprises the steps of accumulating a plurality of items into a first group; then moving the first group in a first generally longitudinal direction; then moving the first group in a first generally transverse direction such that a plurality of items of the first group are loaded into each of the first, second and third trays; and then moving the first, second, and third trays, each loaded with a plurality of items that had comprised the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading first and second trays each with at least one layer of items. The trays are generally longitudinally aligned in series. The method comprises the steps of forming a plurality of items into a first group; then moving the first group in a first generally longitudinal horizontal direction; then moving the first group in a first generally transverse horizontal direction such that a plurality of items of the first group are loaded into each of the first and second trays; and then moving the first and second trays, each loaded with a plurality of items that had comprised the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a system for loading a group of items into an open top tray. The system comprises: an item accumulating conveyor operable to collect a plurality of items into a group at an item loading station and transporting the group of items generally horizontally and longitudinally to a tray loading station; a vertical tray delivery conveyor operable to move a tray carried thereon from an item loading position at which items are loaded from the item accumulating conveyor into the tray, generally vertically to a tray unloading position where the tray carrying the group of items is unloaded from the vertical tray delivery conveyor; and an item discharge apparatus operable to discharge the group of items generally transversely from the item accumulating conveyor to a tray held in the vertical tray delivery conveyor when the tray is at the item loading position.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one layer of items comprised of accumulating a plurality items into a first group of longitudinally oriented items; then moving the first group of items in a first generally longitudinal direction; then moving the first group together in a first generally transverse direction into an tray; and then moving the tray loaded with the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading first and second trays each with at least one layer of items. The method comprises the steps of: a) accumulating a plurality items into a first group and a second group; then b) moving the first group in a first generally longitudinal direction; then c) moving the first group in a first generally transverse direction such that a plurality of items of the first group are loaded into the first tray which is situated at an item loading station; and then d) simultaneously moving the first tray loaded with a plurality of items that had comprised the first group of items in a vertical direction away from the item loading station, and the second tray to the item loading station; e) moving the second group in the first generally longitudinal direction; then f) after (c), moving the second group in the first generally transverse direction such that a plurality of items of the second group are loaded into the second tray which is situated at the item loading station.

According to another aspect of the present invention, there is provided a system for loading a group of items into a tray. The system comprises: an item accumulating conveyor operable to collect a plurality of items into a group oriented longitudinally at an accumulating conveyor loading station and transporting the group of items longitudinally to a tray loading station; a vertical tray delivery conveyor operable to move a tray carried thereon from an item loading position at which items are loaded from the item accumulating conveyor into the tray, generally vertically to a tray unloading position where the tray carrying the group of items is unloaded from the vertical tray delivery conveyor; and an item discharge apparatus operable to discharge the group of items generally transversely from the item accumulating conveyor to a tray held in the vertical tray delivery conveyor when the tray is at the item loading position.

According to another aspect of the present invention, there is provided a system for loading a group of items into a first tray and a second tray. The system comprises: a delivery system operable to deliver a first group of items and a second group of items to a tray loading station; a vertical tray delivery conveyor which is operable to move a first tray carried thereon from an item loading position at the tray loading station, at which first group of items are loaded by the delivery system into the first tray, generally vertically to a tray unloading position where the tray carrying the first group of items is unloaded by the delivery system to the vertical tray delivery conveyor, and the vertical tray delivery conveyor also being operable after the first tray has been loaded with the first group of items, to move the second tray carried thereon to the item loading position at which first group of items are loaded by the delivery system into the second tray, generally vertically to the tray unloading position where the second tray carrying the second group of items is unloaded from the vertical tray delivery conveyor.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one layer of items comprising the steps of: at an accumulating station, accumulating a plurality of items into a first group of longitudinally oriented items; then moving the first group of items in a first direction; then moving the first group of items into a tray; and then moving the tray loaded with the first group of items in a second generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one layer of items comprising the steps of: loading a tray on a tray support device at a tray loading station; moving the tray with the tray support device from the tray loading station to an item loading station at which a plurality of items are loaded into the tray; and moving the tray with the tray support device generally vertically to a tray discharge station at which the tray is discharged from the tray support device.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one group of items comprising the steps of moving a first group comprised of a plurality of items in a first generally longitudinal horizontal direction; moving the first group in a first generally transverse horizontal direction into a tray; and moving the tray loaded with the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one layer of items comprising the steps of accumulating a plurality of items into a first group; moving the first group in a first generally longitudinal horizontal direction; moving the first group in a first generally transverse horizontal direction into a tray; and moving the tray loaded with the first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a system for loading a tray with a group of items comprising: means for moving a first group of items comprised of a plurality of items in a first generally longitudinal horizontal direction; means for moving the first group in a first generally transverse horizontal direction into a tray; and means for moving the tray loaded with said first group of items in a generally vertical direction.

According to another aspect of the present invention, there is provided a method of loading a tray with at least one layer of items. The tray has a base with an upper surface, and a top opening. The method comprises the steps of forming a plurality items into a group of items; moving the first group in a first generally horizontal direction so that the items are received through the opening of the tray to form a layer of items that at least partially covers the upper surface of the base; and moving the tray loaded with the group of items in a generally vertical direction.

DETAILED DESCRIPTION

With reference initially to onlyFIGS. 1A and 2A, a tray loading system10is used to load trays generally designated17with two layers of items11, each layer can have a plurality of items11. Items11can be any kind of item it is desired to arrange in a layer in the tray, and can include but not be limited to food items such as muffins, cookies and the like. Trays17may be any item retaining device having a base portion that is generally flat and a generally, but not necessarily completely, open top portion, through which items can be loaded onto the base to provide a first layer of items that at least partially cover the upper surface of the base. Additional layers of items can be placed on top of the first layer.

Trays17will typically, but not necessarily have a base, and side walls upstanding all around, from the base. The side walls can be relatively high compared to the width and length of the base, but will usually be relatively shallow in comparison to the aforesaid width and length of the base. The base is sometimes, but not necessarily, generally flat. However, the base may be uneven, and could for example, provide for slots or indentations or the like to retain items in a layer.

The open portion at the top may have a folding top panel, or some other type of closure device or lid, to enclose items loaded through the open top, in the tray. Trays17can be made of any type of suitable material for holding the items, including but not limited to plastics, relatively stiff paper material or cardboard.

System10as illustrated, has several components, including an item input conveyor12, an item accumulating conveyor14, a tray input conveyor16, a vertical tray delivery conveyor18and a tray output conveyor20.

The system also includes an item discharge apparatus22for discharging items11from item accumulating conveyor14into trays17, as well as a tray positioning apparatus24(see in particularFIGS. 3A,3B,3C and3D).

Item input conveyor12can be a continuous motion belt-driven conveyor having a continuous belt30supported on either end by one or more rollers33, one or more of which will be driven by a conveyor motor32, and can be constructed in a known manner. Item input conveyor12can be configured to continuously deliver items11singly in series to an accumulating station at which is located an item input for item accumulating conveyor14. In other example embodiments (not shown) it is possible to deliver items in stacks of two or more items.

A plurality of items can be formed into groups. For example, as shown inFIG. 2A, item accumulating conveyor14has a first continuous conveyor belt36supported at either end by rollers37and a second continuous conveyor belt38, also supported by rollers35. Belts36and38are mounted parallel and adjacent to each other, and can be driven independently of each other by separate servo-motors (not shown) or other known conveyor belt driving mechanisms, and can be constructed in a known manner. Belts36and38can move independently of each other, and can move intermittently and at varying speeds. Also as shown, each belt36,38can have a set of spaced flight members, in one example embodiment, thirteen spaced flight members40, provide and define therebetween a total of twelve cavities41. Each cavity41can be configured for receiving and holding an item11(seeFIGS. 1A and 1B). Flights40or other item holding devices can be mounted to the belts36,38in conventional known ways. Although the flights40of each belt36,38extend transversely across the other of the belts36,38, each set of thirteen flights40is only interconnected to one of belts36,38. Thus, each of the sets of flights40can be moved independently of the other set of flights40, by their respective belts.

Positioned generally adjacent to belts36,38and located between the belts and vertical conveyor18, is an item supporting platform15(FIG. 2A) which can be supported by a frame (not shown). Platform15has an upper surface that is located generally parallel to and is located at the same vertical height as the upper surface of the upper run of belts36,38. Thus, items moved transversely by item discharge apparatus22from belts36,38will be moved onto platform15, before being pushed over the edge of platform15to fall into an open topped tray17.

As illustrated, item discharge apparatus22may be configured with a plurality of depending fingers23(FIG. 1A), each for engaging a cavity41of a set of flights40carried by belts36and38. Item discharge apparatus22can be provided with finger elements23depending outward from a main support rod21(FIG. 2A). Apparatus22can employ a transverse sweeping action capable of sweeping items11out from cavities41formed between flight members40into open-topped trays17carried by vertical tray conveyor18. During the sweeping movement to push items into trays17, the fingers23can be oriented downward. On the return movement, as shown inFIG. 2C, the fingers23have been pivoted backwards so that they can pass over flights41of belts36,38and not otherwise interfere with the unloading of items11from the next set of cavities41. As part of apparatus22, a simple overhead conveyor can be mounted with drive chains at either end supporting ends of rod21. The chains can be configured to provide a path for the rod21as shown inFIGS. 2A to 2H. The fingers23attached to rod21can also be rotated about a longitudinal axis defined by the centre of rod21by conventional rotation mechanisms such as a cam follower and cam track configured at either end, similar to the cam follower and track used to rotate wall48bof shelves26as later described. The cam follower can be attached to a bar member attached at an end of rod21, and engage a track that follows a path which produces a relative rotation of the fingers23about the longitudinal axis of rod21.

Vertical tray conveyor18may comprise an endless conveyor having shelf units26secured to, and being supported at either end by continuous chains42and44, generally arranged for parallel vertical runs. Although not shown, but as is known in known conveyor systems, chains42,44can be guided by guide tracks to provide the path shown inFIG. 4D. The continuous conveyor chains can be supported for their vertical runs by rollers (not shown) and as shown by arrows inFIG. 2Acan be driven in an anti-clockwise direction by a conventional drive mechanism (also not shown). Vertical conveyor18can be driven by servo-motors to provide for intermittent motion and movement of varying speed, along the path illustrated, as will be explained in more detail hereinafter.

The movement of the components of system10can be controlled by a Programmable Logic Controller (PLC)100(FIG. 1A), including the movement of item accumulating conveyor14, vertical conveyor18and item discharge apparatus22so as to effect the operational movements described in greater detail below. Additionally, although item conveyor12and tray input conveyor16can be operated continuously at a constant speed, alternatively they can be driven at varying speeds and intermittently by for example servo-motors, with the movement being controlled by PLC100. Various sensors can be provided in the system and be interconnected to PLC100. Such sensors can be used to assist in ensuring the proper sequence of operation of the various components and also be configured to identify if there are certain types of problems with the operation of the system10. For example, if a problem is identified, conveyor12can be stopped, to temporarily prevent the continuous feeding of items to the accumulating conveyor14. A sensor can be placed between infeed conveyor roller33and accumulating conveyor14. Such a sensor can be a beam sensor which emits a beam and so can, by interruption of the beam, sense if the gap between the infeed conveyor roller and conveyor14is blocked for an extended period of time. This beam sensor can be in communication with PLC100and can be configured to provide a signal to PLC100when the gap is blocked. It the gap is blocked for an improper period of time as measured by the PLC100or other timing device, PLC100can shut down the system.

Also an electronic eye sensor device (not shown) associated with the item in-feed location of accumulating conveyor22, can be provided and be in electronic communication with PLC100. The electronic eye would be able to detect the presence or absence of an item11at a cavity41positioned at the item in-feed location. Once a cavity41located at the in-feed location has been filled, the electronic eye can detect the same and send a signal to PLC100. The PLC100can then control the movement of accumulating conveyor14, either to index belt36or38to the next cavity41if not all cavities associated with that set of flights have been filled, or if all cavities are filled to move the respective belt36or38so that the group of items held in the flights40of that belt can be positioned adjacent to item discharge apparatus22.

With particular reference now toFIGS. 4A and 4B, shelf units26of vertical conveyor18are shown in detail. Each shelf unit26is comprised of a base portion46, with upstanding longitudinal side walls48a,48band a single, upstanding end wall50. Walls48a,48band50of shelves26are configured to receive from an opposite end to end wall50, and then hold, three trays17in end-to-end, longitudinally oriented relationship. Shelf units are typically fixedly mounted at their ends to chains42,44and so rotate with chains around the conveyor path of vertical conveyor18. However, as will be evident from the description below, the shelves26are configured for a limited degree of rotation about a longitudinal axis relative to chains42,44facilitated by pivot connections of shelves26to chains42,44. The shelves26rotate relative to the chains, about a longitudinal axis when they move from the tray loading position (FIGS. 2A–2E) to the tray unloading position (FIGS. 2G and 2H).

Side wall48ais fixedly attached to or formed with base46and is upstanding from base46. However, side wall48bis formed from a longitudinally extending L-bracket member which is movable relative to shelf base46, between an extended, tray holding position (as shown inFIG. 4A) and a retracted, tray release position (as shown inFIGS. 4B and 4C). As shown in further detail inFIG. 4C, the end of each shelf can be attached to a chain42(chain44at opposite end of the shelf) by way of a plate member84. Plate member84can be attached to base46with conventional attachment mechanisms or integrally formed therewith. Plate member84can be mounted with nuts and bolts82to the chain. It will be noted, as shown inFIG. 4D, that when a tray is at the item receiving position the upper surface of shelf base46is sloped downwards a few degrees. Side wall member48bhas arms49at both ends (FIG. 4C) which are pivotally mounted for limited rotation about a pin83. Arms49each have a cam follower87attached at the front. Vertical tray conveyor18also has cam tracks85at each end with a groove for receiving the previously mentioned cam followers87. Driving shelf base46with drive chains42and44around the conveyor track of vertical conveyor18, will drag cam follower87which is engaged in its groove, in the paths as shown inFIG. 4D. The path of the track85relative to the chains42,44will then produce relative motion, in particular a rotation, of the side wall48baround its pivoting point and pivot pins83. When shelves26have to receive trays17from conveyor16, side wall48bis standing up and in a tray retaining position. When shelves26are at discharge position then that side wall48bis pivoted downwards about pins83to allow free side sliding motion of the loaded trays from a shelf26onto tray output conveyor20.

As will be noted inFIGS. 2G and 2H, as each shelf26is positioned in the tray release position, whereby the leading longitudinal edge26aof each tray26has rotated anti-clockwise relative to chains42,44, the L-bracket member has rotated anti-clockwise relative to base46to retract the upstanding wall portion48bso that it no longer blocks tray17from being pushed from shelf26by a tray discharge mechanism76, as is described below.

InFIG. 4A, a shelf26carrying loaded trays117,217,317is being lowered by vertical conveyor18. Wall portion48bis in a tray blocking position. InFIG. 4B, tray26is shown in the position where it is unloaded from the shelf, with wall portion48bhaving been retracted. Trays117,217,317have already been discharged from shelf26onto tray output conveyor20and carried away by that conveyor.

With reference toFIGS. 3A to 3D, a tray positioning apparatus24is mounted to a frame (not shown) and includes a plate60mounted to an end of a reciprocating piston62. Piston62is interconnected to and can be powered by a conventional pneumatic reciprocating cylinder63and is operable to move in a reciprocal movement between an extended position as shown inFIG. 3Cand a retracted position as shown inFIG. 3D. This reciprocating motion can be achieved in known ways such as for example, by using a double acting cylinder, which can for example, channel compressed air to two different chambers which in turn provides interchanging forward and backward acting forces on the piston. To channel the compressed air appropriately, valves can be driven between open and closed positions by solenoids responsive to signals from PLC100(FIG. 1A). Piston62has at its extension end a front plate60attached thereto. Plate60is positioned to be able to abut the trailing end face117aof the last carton117in a train of three cartons117,217and317, each of which has been loaded onto a shelf26by tray input conveyor16. Tray positioning apparatus24is positioned so that when a shelf is at a tray loading position, where items11are loaded into the trays, the apparatus can assist in holding the trays in a stable position. This can be accomplished by holding the trays in serial abutment with each other in a slot formed by side walls48a,48b, end wall50of shelf26, and plate60. The plate60may be configured to exert a small axial compressive force on trays117,217,317to ensure that they are stable.

With reference toFIGS. 5A to 5C, a tray discharge apparatus76can include a plate75mounted to an end of a pair of longitudinally spaced reciprocating pistons77. Pistons77can be mounted to a frame (not shown) and interconnected to and powered by a conventional pneumatic reciprocating cylinder device79, in a manner similar to the pneumatic cylinder and piston described above. The pistons77are operable through activation of the pneumatic cylinder79to move back and forward between an extended position as shown inFIG. 5C, through a partially extended position shown inFIG. 5B, and a retracted position as shown inFIG. 5A. This movement can be controlled by valves, solenoids in communication with and controlled by PLC100. Plate75is positioned to be able to abut the trailing side face17cof each of the three cartons117,217and317in the train held on a shelf26when the shelf is at the tray discharge position shown inFIG. 5C. At the position shown inFIG. 5C, the trays117,217and317have been pushed off the shelf26transversely onto tray output conveyor20, by which they can be transported away for further processing.

With reference again toFIG. 1A, the tray input conveyor16includes an endless belt66supported at either end by rollers61, one or more of which can be driven by a motor70which may provide for continuous or intermittent movement and for a constant or varying speed. In this embodiment belt66is driven for continuous movement at a substantially constant speed and carries on its upper surface a plurality of trays17, generally in serial abutment with each other.

Input tray conveyor16delivers trays17toward vertical tray conveyor18. Trays can be delivered in batches. Each batch can comprise a lead tray317, a middle tray217and a trailing tray117(seeFIG. 7A). Tray conveyor16will push the batch of trays117,217,317onto a shelf26of vertical conveyor18. As conveyor16is running continuously, a tray retaining apparatus (only finger80of which is shown) is provided to retain each batch, until such time as a shelf26is ready to receive a batch of three trays. Various tray retaining apparatus can be used, and the tray retaining apparatus can for example be a walking beam conveyor and can have a tray retaining finger or member80depending downwardly therefrom. Such a finger80can be deployed on an intermittent basis to engage an interior face of trailing end wall317a, of the leading tray317in each batch of three trays, when it is desired to restrain a batch of trays117,217,317. When tray member80is in the position shown inFIGS. 6A and 7A, engaging the inside face of rear wall317aof the leading carton317, conveyor belt66will just slide underneath and against the bottom surfaces of the trays, movement of the trays toward the in-feed for vertical conveyor18being restricted by member80. When it is desired to load three trays117,217,317onto a shelf26, finger80is raised (FIGS. 6B and 7B), allowing three trays117,217,317to pass by. The movement of member80can also be controlled by PLC100and an electronic eye or other sensor can be used to detect when an empty shelf26is in position ready to receive a batch of trays. Other mechanisms can also be employed to effect the operation of the member80to release one batch of trays and then restrain the following batch.

The operation of tray loading system10will now be described. In this embodiment, items11are shown being fed serially and continuously in turn by item input conveyor12, into cavities41that are positioned at an item receiving location of item accumulating conveyor14. Items11would be positioned at an appropriate spacing on conveyor12for proper feeding to accumulator14. Sequentially, first all of the cavities41defined by the flights of one of belts36and38are filled in turn with an item11. This is accomplished by indexing the respective belt36,38carrying the cavities currently to be filled, so that each cavity receives a single item11. Once one cavity is filled, the belt is indexed so the next cavity in the set is positioned ready to receive and then does receive an item11. The flow of items needs to be controlled so items11are fed properly to accumulating conveyor14. The use of a sensor to detect the filling of a cavity could be used in conjunction with PLC100to ensure the proper movement of conveyor12and accumulating conveyor14.

Once each of the cavities41in the set of cavities on the belt has been filled, that set of flights is moved by moving the appropriate belt36or38of accumulating conveyor14, along the conveyor path so that the flights40and their respective cavities41are aligned with the fingers or sweep members23of the item discharge apparatus22(FIG. 1A), as well as a set of trays117,217,317held on a shelf26of vertical conveyor18. It will be noted fromFIGS. 2A and 2B, that the top openings of trays117,217,317are disposed slightly below the horizontally oriented top side runs of belts36and38and the upper surface of platform15, so that when item discharge apparatus performs its sweeping action it will transfer the items in each of the cavities between flights40across platform15into transversely positioned trays.

FIGS. 1A to 1Fshow the sequential movement of belts36and38. InFIG. 1A, belt36is being indexed to complete the filling of the cavities of its set of flights. Belt38has already previously discharged the items11held in its flights into an earlier delivered batch of trays and is holding at, or moving to, a waiting position upstream of the item input position from item input conveyor12. At this waiting position, flights40of belt38do not interfere with the completion of the filling of the flights40of belt36.

FIG. 1Bshows flights from belt36having been previously filled with items11and moved to the tray loading position, are in the process of being discharged from the cavities41of item accumulating conveyor14by item discharge apparatus22. At the same time, the flights40associated with belt38are starting to have their cavities41filled with items11from accumulating conveyor12.

InFIG. 1C, the discharge of items11from the flights of belt36has been completed and the items have filled one layer of trays117,217and317. At the same time, the process of filling the set of cavities41of belt38is continuing.

InFIG. 1Dit is shown that the filling with items11of cavities41of belt38is close to being completed. Additionally, restraining member80has moved upwards to release another batch of trays117,217and317so that they move onto a vertically aligned second shelf (above the first shelf positioned vertically below and carrying the first batch of trays117,217,317that are currently being filled).

InFIG. 1E, item discharge apparatus22is in the process of discharging items11from the cavities41of belt38across platform15and over the edge of platform15, to fall into trays17so that a second layer of items11can be provided on top of the first layer of items, in each of the trays117,217,317. As the drop from platform15is typically relatively small, there will not be an opportunity for items11to become disoriented when they land in the trays. Furthermore, it is usually not critical that the items11be perfectly positioned in the tray, although they should be lying substantially flat. Additionally, the flights40of belt36have now already started to be moved past the item in-feed position such that two items11have already been fed from conveyor13into two of its cavities41. Additionally, in the second batch of trays117,217,317being fed from tray input conveyor16onto a shelf26of vertical conveyor18, all three trays have almost been pushed onto the shelf26positioned adjacent conveyor16.

InFIG. 1F, the loading of items11into the trays by item discharge apparatus22has been completed, as the items11held in cavities41of belt38have been pushed across platform15into trays117,217,317. The result is the loading of two layers of items11into the batch of trays117,217,317. Discharge apparatus22has commenced its return movement, with fingers23being raised to ensure that in the return movement, they do not contact the items held in the cavities of belt36, some of which are still in the process of being filled. Additionally, the next batch of trays has now been fully loaded onto the shelf26adjacent tray input conveyor16, and restraining member80has been lowered and moved backwards to form a gap between the trailing tray117of the just loaded batch of trays, and the leading tray317of the next to be loaded batch of trays. The gap relieves any pressure which would otherwise be applied to the trailing wall117aof tray117by the leading wall of leading tray317of the to be loaded batch of trays. Thus, member80will restrain the next to be loaded batch of trays, while the vertical conveyor moves the just loaded batch of trays downwardly to the item loading position, and the risk of tray117being upended from any such pressure is reduced or eliminated.

After the operations shown inFIG. 1F, the movement of vertical conveyor18will commence to move the just filled batch of trays away from the item loading position, and moves the just loaded batch of trays to the item loading position.

The system will have then completed one cycle and will move again to the positions shown inFIG. 1A.

Referring now toFIGS. 2A to 2H, the process of transfer from item accumulating conveyor14to vertical conveyor18is shown in further detail. InFIG. 2A, item discharge apparatus22is shown commencing a sweep of items11from item accumulating conveyor14across platform15into trays17. This position shown inFIG. 2Acorresponds with the position of discharge apparatus22shown inFIG. 1A. As shown inFIG. 2A, a shelf26with trays17is positioned with its top edge slightly below the upper run of belts36and38and the upper surface of platform15. The front edge of the trays is positioned a short horizontal and vertical displacement from the adjacent edge of platform15. Thus, as shown inFIG. 2B, as item discharge apparatus22has almost completed its sweep (corresponding with the position of discharge apparatus22shown inFIG. 1B), items11move across platform15and will fall into trays17which can be held in a substantially stationary position by vertical conveyor18. The precise positioning of the tray relative to the edge of platform15can be selected to ensure that items11will usually, if not always, fall into the batch of trays117,217,317in their proper configuration. The proper positioning of items as they are loaded into trays117,217,317is assisted by the slight downward sloping of shelf26at the item loading position (which can be sloped downward at for example between about 1 and 10 degrees and preferably about 5 degrees). This sloping of the shelf can be effected by the path of the chains of the conveyor18and mounting of shelves thereon.

FIGS. 2C,2D,2E and2F show the sequential movement of item discharge apparatus22sweeping a second layer of items11into trays17. As shown inFIG. 2C, fingers23have been pivoted rearwardly about their longitudinal axis of rod21, during the return transverse movement. InFIG. 2D, fingers23have been rotated back to a substantially vertical orientation, and are about to commence a sweeping action to sweep the second layer of items11into trays117,217,317. InFIG. 2E, the fingers23have pushed the second layer of items11to the edge of platform15and those items are about to fall into trays117,217,317.

InFIG. 2F, the fingers23have been rotated by rod21in preparation from the return transverse movement to the other side of belts36,38. InFIG. 2G, the fingers23are returning to the transverse position where they will be ready for the next sweeping action, and inFIG. 2Hthey are ready to sweep a first layer of items11into the next batch of trays which have been lowered into the tray loading position by vertical conveyor18. The loading cycle has thus substantially returned to the configuration shown inFIG. 2A.

It should be noted that it may be possible to configure the overall system10so that the next batch of trays117,217,317to be loaded can be placed onto the next shelf26during the loading of the first layer of items11in the current batch of trays. Optionally, if the loading of the next shelf with trays from conveyor16is completed, a small vertical adjustment by conveyor18may possibly be of assistance in some applications or embodiments, so that the position of the current batch of trays being loaded can possibly be moved up, or more likely down, a small amount, to help ensure that the first layer of items is loaded properly and the second layer of items will be loaded properly, with a reduced risk of improper placement into the trays on top of the first layer of trays.

In the movement as shown inFIGS. 2E and 2F, item discharge apparatus22is in its return movement back to the ready position and the vertical tray delivery conveyor18has commenced the movement of the shelf carrying the loaded trays (as well as all the other shelves which are attached to vertical conveyor18) downwards and in an anti-clockwise direction towards tray output conveyor20.

With reference to that ofFIG. 2G, the shelf26carrying the loaded trays reaches a tray discharge position, shown inFIG. 2G. At this position, the shelf base46can be oriented more steeply downward from the horizontal, such as for example about 15 degrees. Also with reference toFIG. 5C, at this position, the L-bracket sidewall48bhas been pivoted about a longitudinal axis on pins83such that the sidewall48bhas been retracted. Tray pushing apparatus76has been operated so that longitudinal oriented plate75is translated transversely downward to push the trays from shelf26onto tray output conveyor20(see alsoFIG. 5B). Pistons77are then retracted as shown inFIG. 2H, which will then allow vertical conveyor18to operate to move the just unloaded shelf26away from the tray unloading position. It should be noted that the positioning of shelves is such that as one shelf26is discharging its trays onto conveyor20, another shelf26is positioned to start receiving items from item accumulating conveyor14.

With reference now toFIGS. 3A to 3D, tray positioning apparatus24is shown in operation. Prior to a shelf26and its trays being held thereon starting to receive items11from item accumulating conveyor14, the piston62of tray positioning apparatus24is actuated such that plate60abuts the trailing wall117aof the trailing tray117and pushes into tray117,217and317into abutment with each other up against end wall50of shelf26. Plate60remains in abutment with the end wall117aof tray117during the loading process. After the second layer of items has been loaded from item accumulating conveyor14, piston62is retracted to release the tray117which permits vertical conveyor18to rotate in an anti-clockwise direction to move the shelf26and trays117,217and317contained therein to the tray output conveyor20.

With reference toFIGS. 4A,4B,4C, and4D, the detailed movement of the L-bracket member that forms side wall48bof shelf26is shown in detail. The detailed view inFIG. 4Acorresponds substantially with the view of the shelf having trays with items, as shown inFIG. 2F. The position of wall48band shelf26shown inFIGS. 4B and 4Ccorresponds with the position of the system shown inFIG. 2H. It will be observed fromFIG. 4D, that as the shelves reach the tray unloading position, the relative movement of the cam follower in track85has produced the rotation of wall48b. This causes wall48bto be lowered releasing the trays from the shelf26, and they can then be pushed transversely onto conveyor20.

It is understood that the term “tray” as used herein describes any container or holder with some kind of retaining wall(s) and an open top, such as an open-topped box. Although the invention has been described employing various specific components such as item supply conveyor12, tray supply conveyor16, item accumulating conveyor14and vertical conveyor18, other types of apparatus can be employed to achieve the same movements. For example, instead of vertical conveyor18, other devices capable of moving trays vertically between the different stations can be employed.

The foregoing described only preferred embodiments, and modifications and variations will readily become apparent to those of ordinary skill in the art without departing from the scope of the invention as defined by the claims hereinafter.