IE893475A1

IE893475A1 - Handling systems for food products

Info

Publication number: IE893475A1
Application number: IE347589A
Authority: IE
Original assignee: Oseney Ltd
Priority date: 1989-10-27
Filing date: 1989-10-27
Publication date: 1991-05-08
Also published as: GB2237271A; BE1001791A6; GB9001450D0; GB2237271B

Abstract

A processing chamber 1 for food products has a number of treatment floors one above the other. A lift (5) (fig. 2, not shown) transfers incoming products carried on trays from a supply conveyor 3 to any selected one of floors. A similar lift 6 transfers products being discharged from the chamber 1 to a downstream conveyor 4. The lifts are each provided with a transfer mechanism for transferring a tray 12 carrying food product from lift 5 to a floor or from a floor to lift 6 respectively. The transfer mechanism includes a carriage 11 which can travel outboard of the lift 5 or 6 to engage a tray 12 carrying the food products by means of a ratchet member 14. Return movement of carriage 11 draws the tray 12 onto the lift 6, where it is advanced to a discharge position by a further ratchet configuration independently driven tooth 18. Simultaneously with this advance of the tray 12, carriage 11 returns to a disposition in which a second ratchet 15 engages against a rear face 19 of the tray 12. When the lift 6 is aligned with the discharge conveyor 4, a second forward movement of the carriage 11 drives tray 12 forward from lift 6 onto conveyor 4.

Description

The present invention relates to handling systems for food products. In particular, the invention is directed to a system for handling food products during a treatment step in a food production process. The invention also relates to an input/output feed mechanism for a treatment unit in a food processing system, and to a tray for use in such a system.

In the production of food products, control of the environment in which the food product is contained is frequently required. Depending on the process involved, it may also be necessary to transfer a product into a controlled-environment region where it undergoes a specific treatment, such as heating or cooling, for a period during a manufacturing process. This transfer may involve bringing products to a treatment unit on a single conveyor and transferring them to multiple conveyors for the treatment phase, and subsequently collecting the products from the multiple conveyors, after the treatment step, for advancing the treated products to further production stages on a single conveyor.

USSR Patent No. 1.346.538A describes an inter-conveyor reloading device having a frame with two conveyors at different levels and a vertically movable table mounted in guide means on struts. The device is used for transfer of items from one conveyor to another located at a different level. German Patent Specification No. 2,110,979 describes an endless conveyor for piece goods in which carriages with lifting platforms cooperate with vertically displaceable loading conveyors. Systems are also known for displacements of products between a single conveyor and multiple conveyors. Netherlands Patent Specification No. 6,918,904 provides apparatus for transferring rows of containers from a series of carriers to parallel discharge tracks. A transfer device is arranged to guide the containers to one or other of the two tracks. Alternative distribution arrangements for connecting vertically spaced parallel conveyors may also be employed, such as the helical conveyor described in U.S. Patent Specification No. 3,845,853.

In any of the various arrangements noted, reciprocating transporting arangements may be used for displacing products along a conveyor track. An example of an arrangement of this kind is described in U.S. Patent Specification No. 4,487,308.

There are also known trays and other containers for carrying food products and other articles, in which one or more walls of the tray are displaceable, for example for convenience in handling the product or for allowing the container to be collapsed for ease of storage or return of the unladen tray.

US Patent Specification No. 4,248,349 provides a tray for ampoules having pivotable end walls. British Patent Specifications Nos. 2,017,637A and 1,571,703 disclose wiremesh-type containers or baskets having removable panels, while British Patent Specification No. 2,051,172A and French Patent Specification No. 2.447.324A relate to collapsible containers or cases, folding flat for storage.

It is an object of the present invention to provide an improved handling arrangement for food products capable of transferring product between a single conveyor and a plurality of floors, such as the floors of a product treatment unit, for example. A further object of the invention is the provision of a food product handling arrangement capable of use with other steps or systems in food product processing. A still further object of the invention is the provision of a food product support unit or tray allowing ready transfer of product to and from the support unit or tray.

According to a first aspect of the invention, there is provided a handling system for transferring food products to and from a processing unit having a plurality of treatment floors disposed one above the other, the handling system comprising (a) a lift unit for selective alignment with an infeed or outfeed conveyor and/or any selected one of said treatment floors, and (b) drive means carried on said lift unit for transferring product between said lift unit and said feed conveyor or between the lift unit and a treatment floor.

The drive means preferably comprises a travelling carriage mounted on the lift unit for displacement into a product collection disposition in which a portion of the carriage is located outboard of the lift unit. This carriage is suitably provided with a first drive mechanism for engaging product carried on a support means for drawing the product support means onto said lift unit during a product-collection operation. The carriage is preferably also provided with a second drive mechanism for advancing said product support means forward from said lift unit onto an outfeed conveyor or a treatment floor as required during a product discharge operation. The lift unit also suitably comprises a further or third drive mechanism for advancing a product support means or tray from a reception location on the lift unit at which it is disposed following completion of a product-collection operation by said carriage, to a discharge location in which a driving or discharge operation may be carried out by said second drive mechanism for advance of the product support means or tray to a treatment floor or output conveyor.

The third mechanism is preferably operable independently of the position of the carriage. In particular, the third drive mechanism may be operable for forward movement of a product support or tray from the product-collection disposition on the lift unit to the product discharge disposition while a reverse movement of the carriage takes place, following completion of a product-collection operation, to bring the carriage into a position in which it may carry out a product discharge operation. The carriage is suitably mounted for travelling movement along the lift unit and for movement into said outboard disposition at the product-collection end or side of the lift. The drive mechanisms may include ratchet or dog type arrangements, active for advancing movement in a forward direction only and arranged to underrun a product support means or tray during return or reverse movement of the carriage or drive mechanism.

In another aspect, the invention provides a treatment system for food products, comprising a chamber having a plurality of treatment floors arranged one above the other and at least one handling system according to the first aspect of the invention. Preferably two such handling systems are provided, one for input of product to the chamber and the second for product discharge to an outfeed conveyor. A control arrangement may be provided for input of selected product to a selected one of said treatment floors as required.

Drive means, preferably in the form of ratchet mechanisms, are provided for advance of product from the input end of the cooling chamber to its output end along each treatment floor.

In a third aspect, there is provided, according to the invention, a product-carrying tray for use in food processing, comprising a frame and a planar portion for underlying product carried on the tray, said planar portion being displaceable relative to the frame between lower and upper stops. Preferably the planar portion is an openwork mesh-form structure and the frame includes a sidewall portion, which may be defined by the vertical limb of a section of L-shaped material, the upper stops being placed so that in an uppermost disposition of the planar member, its surface is substantially aligned with the upper edge of said sidewall portion, i.e., the vertical limb of the L-shaped frame. In operation for carrying product, this sidewall portion or vertical limb of the L-shaped frame surrounds the planar member and provides a rim around the sides of the tray, with the wireform planar member in its lowermost position. In this way, product is prevented from falling over the sides of the tray. For discharge of product, the planar member is displaced into an uppermost disposition against the upper stops and product may then be swept off the planar member without any snagging on the rim, while product may also be loaded onto the planar member in convenient manner under these circumstances.

In a still further aspect, there is provided a handling system for food products carried on trays according to the foregoing aspect of the invention, wherein the system comprises drive means for displacing the planar member of the tray between its upper and lower dispositions, for loading and discharge of product onto the tray and from it. The handling system according to the invention for food products carried on trays according to the foregoing aspect of the invention may also comprise a conveyor having means for displacing the planar member of the tray into its uppermost disposition, along with means, such as a diagonally-disposed sweeping blade, for directing product carried on said planar member towards a discharge location for packing or further treatment.

Embodiments of the invention will now be described having regard to the accompanying drawings, in which Figure 1 is a diagrammatic pictorial view of a food product treatment system according to the invention, Figure 2 is a schematic sectional side view of the treatment system of Figure 1, Figures 3 to 8 are schematic representations of the progression of operations in a product handling system according to the invention from the collection of a product tray from the discharge end of a treatment system according to Figures 1 and 2 to final placement of the tray on an outfeed conveyor, Figure 9 is a pictorial view of a tray suitable for use in product handling systems according to the invention, Figure 10 is a plan view of the frame of the tray of Figure 9, Figure 11 is a plan view of the wiremesh portion of the tray of Figure 9, Figure 12 is a sectional view of the tray of Figure 9 showing the upper and lower side stops, Figure 13 is a sectional view of the frame of the tray of Figure 9 showing part of the lower stop arrangements, Figure 14 is a schematic representation of the tray of Figures 9 to 13 in a carrying configuration, Figure 15 is a schematic representation of the tray of Figures 9 to in an upward loading and discharge configuration, and Figure 16 is a pictorial representation of a plurality of trays according to Figures 9 to 13 on a discharge conveyor together with a sweeping blade for removal of treated product from the trays.

As shown in Figure 1, there is provided a food product treatment system comprising a chamber 1 having six treatment floors 2a to 2f. A feed conveyor 3 brings product to the chamber 1 and a discharge conveyor 4 carries it away again following treatment. A feed lift 5 provides for transfer of arriving product, typically carried on trays, from feed conveyor 3 to a selected one of treatment floors 2a to 2f. A similar discharge lift 6 provides for removal of product from a selected treatment floor and transfer of the product trays to the discharge conveyor 4.

These arrangements are also shown in Figure 2, with the discharge lift 6 being shown in each of Figures 1 and 2 located at the treatment floor 2d. Chamber 1 may be a cooling chamber, in which cool air is directed through the treatment floors in a counter-current arrangement.

Alternatively, chamber 1 may serve for other treatment stages in a food production process, including heating or the maintenance of temperature at a controlled level for a specified treatment period.

It will be apparent that the functioning of the feed and discharge lifts 5 and 6 are crucial to success of a system of this kind, in that the lift mechanisms must be fast, precise and preferably also light in weight, so as to be able to place incoming product at the correct level speedily and also to collect emerging product at the appropriate time and floor for transfer to the discharge conveyor. Product travels through each floor driven forward by ratchet mechanisms or other drive arrangements arranged, for example, to engage the trays on which the product is carried and advance them stepwise along the treatment floor. The system may comprise a control arrangement for selecting and instructing each lift to place particular products on a particular floor and to move to appropriate floors for collection of particular products as they reach the output end of the system.

Microprocessor control facilitates this aspect of operations.

A lift mechanism according to the present invention is shown in Figures 3 to 8. As shown, a discharge lift 6 is in question, but a precisely similar arrangement may be provided at the input side of the chamber 1. - 7 IE 893475 Referring firstly to Figure 3, discharge lift 6 is aligned with treatment floor 2d. A carriage mechanism 11 is mounted on lift 6. Carriage 11 is displaceable along the length of lift 6 and is also capable of movement outboard of the lift at its lefthand or product collection end, for engagement of a tray 12 carried on treatment floor 2d. Tray 12 has an engagement edge 13, subsequently described in more detail in connection with a later Figure, for engagement by a carriage collection ratchet or dog 14, provided at the lefthand end of the carriage. At its other end, the carriage has a drive ratchet or dog 15, operation of which is again subsequently described. In addition, the lift itself has a belt or chain drive mechanism 16, mounted on wheels or rollers 17, and carrying a third drive dog or ratchet 18. The functioning of these various components will become clear having regard to the following further description of Figures 4 to 8.

Considering now Figure 4, starting from the initial configuration of Figure 3, where carriage 11 is inboard of lift 6, carriage 11 first of all moves outboard of the lift 6 so that collection ratchet 14 underruns the engagement edge 13 of tray 12. At this stage, movement to the left of carriage 11 into its outboard configuration terminates. The next step consists of a tray collection displacement during which carriage 11 travels to the right, back onto lift 6 and almost to the righthand end of the lift, to draw tray 12 onto lift 6 into an initial reception or collection location.

The configuration of the mechanisms involved on completion of this operation are shown in Figure 5. Immediately the tray enters into the reception region, drive of the belt or chain 16 commences, and as shown in Figure 4, drive dog 18 will be seen to have started its forward movement directed to bringing it into a driving engagement against the rear face 19 of the tray.

The next stage of operation is shown in Figure 6, where a number of movements are progressing simultaneously. Since the tray is now entirely inboard of lift 6, downward displacement of the lift towards discharge conveyor 4 has commenced. At the same time, continuing drive of chain belt 16 has brought drive dog 18 onto the upper surface of the lift for engagement against rear face 19 of tray 12 and forward drive of the tray from its reception or collection location on the lift towards a discharge location where the leading edge of the tray, designated by original tray engagement edge 13, is adjacent to the discharge end or side of lift 6. While this forward movement is taking place, a rearward displacement of carriage 11 is also in progress, with ratchets 14 and 15 underrunning the edges of the tray without impeding the forward drive of the tray during this stage.

Referring now to Figure 7, lift 6 has descended further towards its lowermost disposition at which it is aligned with discharge conveyor 4.

Drive dog 18 has completed its forward action and tray 12 has been placed at a discharge location on the conveyor. Drive of belt or chain 16 has been reversed and drive dog 18 is returning towards its initial location.

Leftward movement of lift carriage 11 has also been completed and the carriage is now positioned to carry out a discharge displacement to the right, ratchet 15 being placed immediately to the rear of rear face 19 of the tray for forward action against this rear face as soon as lift 6 becomes aligned with discharge conveyor 4.

The final stage of the operation is shown in Figure 8. Lift 6 is now aligned with discharge conveyor 4, carriage 11 has again moved to the right, with ratchet 15 engaged against the rear face 19 of the tray to drive the tray forward from the discharge location on the lift 6 onto the discharge conveyor 4. At this stage all operations have been completed and the carriage may then move back into its starting position during movement of the lift 6 to the next location at which it is required to undertake a collection operation from a further treatment floor. The cycle continues under instructions from the control system of the treatment unit as long as there are trays to be collected.

Precisely the same sequence of activities or operations is carried on at the input side of the chamber. In this instance however, trays are always collected from the feed conveyor, so that collection movement takes place at one level only. By contrast, discharge movements from the lift 5 take place at whichever one of the six treatment floors is currently selected.

Operation on this side of the chamber is therefore substantially a mirror-image of that at the outlet.

A tray especially suited to use in the system previously described is shown in pictorial view in Figure 9, with further details in the following drawings. Referring therefore to Figures 9 to 13, the tray has a frame 21 formed from L-section material, having a vertical limb 22 and a lower horizontal flange 23, which defines the engaging edge 13 previously adverted to.

The carrying surface of the tray is defined by a wiremesh structure 24, supported within frame 21 on transverse bars 25 and end spigots 26 which define lower stops of the tray structure. Wiremesh 24 is vertically displaceable within frame 21 from a lowermost disposition in which it rests on lower stops 25 and 26 into an upper disposition in which it engages against upper stops 27. These upper stops consists of inverted L-shaped pieces of flat bar, extending inwardly from the upper edge of vertical limb 22 of the frame before turning downwardly with vertical portions 28, the lower ends of which are welded onto transverse bars 25 near their points of connection to the frame. Pockets 29 are formed along the sides of the generally rectangular wiremesh portion of the tray and these pockets are entrapped or engaged by the stop members 27 and 28, so that the wire frame cannot be removed from the tray assembly but is displaceable from its lowermost disposition resting on the lower stops into an uppermost disposition in which the outer peripheral portion of the wire frame, enclosing the outer boundaries of the pockets, engages against the upper stops 27.

When the tray is in this uppermost disposition, the plane defined by the wire mesh framework 24 is substantially aligned with the upper edge of vertical limb 22. In this configuration of the tray, loading and unloading, such as by sweeping off of food products carried on the tray, may be readily achieved. When the wiremesh member is in its lower disposition, the vertical limb 22 of the frame forms a positive boundary or rim preventing the product from falling off the tray during handling, such as being passed through a treatment system as previously described.

Figures 14 and 15 show the tray of the invention in its carrying disposition, with the wiremesh member against the lower stops, Figure 14, and driven upwardly by a drive means designated by reference 31, in Figure 15, to bring the wiremesh member into this substantial alignment with the upper edge of vertical limb 22. Infeed or outfeed means 32 and 33 are also shown in Figure 14, to indicate the close alignment between the plane of the wiremesh member and the infeed and outfeed levels, for ease of transfer of product at this stage.

It will be appreciated that alternative configurations of tray may be provided. In particular, the wiremesh floor may be replaced by a continuous or solid plate, while alternative arrangements may define the upper and lower - 10 IE 893475 stops. For example, the periphery or rim of the tray may be defined by outwardly-opening channel-section material. Displacement of the planar member may be guided and limited by laterally-extending spigots engaged in vertical closed-end slots in the web of the channel, so that the upper and lower ends of the slots define the upper and lower stops. The spigots may have enlarged ends, so that they cannot be withdrawn from the slots in the axial direction of the spigots. Many other constructions will also be apparent within the scope of the present invention.

Finally, Figure 16 shows a further feature of a food product handling system according to the invention for cooperation with the tray of Figures 9 to 13 for product discharge. Conveyor 41 has transverse slats 42, of somewhat lesser length than the width of the trays 43 and spaced along the belt so that at least two slats underlie the wiremesh screen 24 of each tray, when the tray rim 21 is placed on the conveyor over the slats. The height of the slats on conveyor 41 is also selected so as to raise the wiremesh screens upwards to be level with the top edges of the rims 21. Thus a number of trays placed on conveyor 41 with their transverse edges in juxtaposition essentially define a single planar surface on which the food product is carried. The food product can then be removed from this level surface by a diagonally arranged sweep blade 44, which diverts the product sidewise and off the upper surfaces of the wire screens during travelling motion of the conveyor and the trays carried on it. Thus use of the tray provided by the invention further facilitates economical handling of food product in food manufacturing systems.

Claims

1. A handling system for transferring food products to and from a processing unit having a plurality of treatment floors disposed one above the other, the handling system comprising (a) a lift unit for selective alignment with an infeed or outfeed conveyor and/or any selected one of said treatment floors, and (b) drive means carried on said lift unit for transferring product between said lift unit and said feed conveyor or between the lift unit and a treatment floor.

2. A handling system according to Claim 1, wherein the drive means comprises a carriage mounted on the lift unit for displacement into a productcollection disposition in which a portion of the carriage is located outboard of the lift unit.

3. A handling system according to Claim 2, wherein the carriage is provided with a first drive mechanism for engaging product carried on a support means for drawing the product support means onto said lift unit during a product-collection operation.

4. A handling system according to Claim 3, wherein the carriage is provided with a second drive mechanism for advancing said product support means forward from said lift unit onto an outfeed conveyor or a treatment floor as required during a product discharge operation.

5. A handling system according to Claim 4, wherein the lift unit comprises a third drive mechanism for advancing a product support means from a reception location on the lift unit at which it is disposed following completion of a product-collection operation by said carriage, to a discharge location in which a driving or discharge operation may be carried out by said second drive mechanism for advance of the product support means to a treatment floor or output conveyor.

6. A handling system according to Claim 5, wherein the third drive mechanism is operable independently of the position of the carriage.

7. A handling system according to Claim 6, wherein the third drive 12 IE 893475 mechanism is operable for forward movement of a product support or tray from the product-collection disposition on the lift unit to the product discharge disposition while a reverse movement of the carriage takes place, following completion of a product-collection operation, to bring the carriage into a position in which it may carry out a product discharge operation.

8. A handling system according to any of Claims 2 to 7, wherein the carriage is mounted for travelling movement along the lift unit and for movement into said outboard disposition at the product-collection end or side of the lift.

9. A handling system according to any of Claims 2 to 8, wherein the or each drive mechanism includes a ratchet or dog type arrangement, active for advancing movement in a forward direction only and arranged to underrun a product support means during return or reverse movement of the carriage or drive mechanism.

10. A treatment system for food products, comprising a chamber having a plurality of treatment floors arranged one above the other and at least one handling system according to any preceding claim.

11. A treatment system according to Claim 10, comprising two handling systems, one for input of product to the chamber and the second for product discharge to an outfeed conveyor.

12. A treatment system according to Claim 10 or Claim 11, wherein a control arrangement is provided for input of selected product to a selected one of said treatment floors.

13. A treatment system according to any of Claims 10 to 12, wherein drive means are provided for advance of product from the input end of the chamber to its output end along each treatment floor.

14. A tray for carrying product in food processing, comprising a frame and a planar portion for underlying product carried on the tray, said planar portion being displaceable relative to the frame between lower and upper stops

15. A tray according to Claim 14, wherein said planar portion is an - 13 IE 893475 openwork mesh-form structure and the frame includes a sidewall portion, the upper stops being placed so that in an uppermost disposition of the planar member, its surface is substantially aligned with the upper edge of said sidewall portion, and said sidewall portion surrounding the planar member and defining a rim around the sides of the tray when the planar member in its lowermost position.

16. A handling system for food products carried on trays according to Claim 14 or Claim 15, comprising drive means for displacing the planar member of the tray between its upper and lower dispositions, for loading and discharge of product onto the tray and from it.

17. A handling system for food products carried on trays according to Claim 14 or Claim 15, comprising a conveyor having means for displacing the planar member of the tray into its operative position and means for directing product carried on said planar member towards a discharge location.

18. A handling system for food products substantially as described herein with reference to and as shown in Figures 1 to 8 or Figures 15 or 16 of the accompanying drawings.

19. A treatment system for food products substantially as described herein with reference to and as shown in Figures 1 to 8 of the accompanying drawings.

20. A tray for food products substantially as described herein with reference to and as shown in Figures 9 to 14 of the accompanying drawings.