WO2014199161A1

WO2014199161A1 - Traysealing apparatus

Info

Publication number: WO2014199161A1
Application number: PCT/GB2014/051805
Authority: WO
Inventors: Lee Vine
Original assignee: Ishida Europe Limited
Priority date: 2013-06-13
Filing date: 2014-06-12
Publication date: 2014-12-18
Also published as: GB201310529D0

Abstract

A traysealing apparatus (100) is provided. The traysealing apparatus (100) comprises a traysealing machine (10) comprising first (11) and second (13) traysealing tools operable to perform respective first and second traysealing processes on trays (20, 22) to be sealed, wherein the first (11) and second (13) traysealing tools are located side by side, first (1) and second (5) infeed lanes and first (3) and second (7) outfeed lanes for transferring trays (20, 22, 24) to and away from their respective traysealing tool (11, 13), and transfer means (9) for transferring trays (22) that have been subjected to the first sealing process from the first outfeed lane (3) to the second infeed lane (5), wherein in use the movement of trays (20, 22, 24) through the first (11) and second (13) traysealing tools is in opposite directions.

Description

TRAYSEALING APPARATUS

Field of the Invention

The present invention is directed towards a traysealing apparatus having a particularly advantageous application in food packaging systems.

Background to the Invention

In the food packaging industry, a common method of sealing containers (such as trays) of food is to use a skin sealing process. In this process, a plastic film such as LDPE or PVC is heated and placed over the food product. Due to softening by heat, the plastic film follows the contours of the food product and forms a close-fitting seal. Such skin sealing advantageously increases the shelf life of the food product, which typically include meat and fish products, and is therefore increasing in popularity.

However, as the sealing film in the skin sealing process follows the (typically uneven) contours of the food product, this presents a number of disadvantages as compared to the flat surface associated with a conventional top seal, including:

• The top surface of the product is commonly used by vendors to display nutritional and marketing information at point of sale - an uneven top surface makes this difficult;

• An uneven top surface makes automatic handling of the packaged food product (such as by "pick and place" systems, for example those produced by Ishida Europe Limited) difficult; and,

• An uneven top surface makes stacking and displaying the product more difficult. In order to overcome these difficulties, producers often apply an additional top seal layer in addition to the skin seal layer, so as to benefit from both an increased shelf life and easier handling of the packaging. Conventionally this is carried out by two traysealing tools positioned one after the other on a food production line. The food product is first subjected to a skin sealing process in the first traysealing tool and subsequently a flat top seal is applied in the second traysealing tool. However, the use of two traysealing tools in this manner greatly increases the length of the food packaging line, taking up valuable factory floor space. Further, packaging materials have to be transferred greater distances and machine operators have to move between the two machines.

GB10041 11A discloses a carton sealing apparatus in which cartons are sealed first by jaws, before being transferred onto an oval shaped conveyor, and subsequently onto a linear conveyor for transferring to a second sealing process. This is an example of a sealing apparatus which takes up a large area of factory floor space, and in which the sealing processes occur in disconnected and isolated sealing machines.

There is therefore a need to reduce these inefficiencies in using two traysealing tools.

Summary of the Invention

In accordance with the invention there is provided a traysealing apparatus comprising; a traysealing machine comprising first and second traysealing tools operable to perform respective first and second traysealing processes on trays to be sealed, wherein the first and second traysealing tools are located side by side; first and second infeed lanes and first and second outfeed lanes for transferring trays to and away from their respective traysealing tool; and transfer means for transferring trays that have been subjected to the first sealing process from the first outfeed lane to the second infeed lane, wherein; in use the movement of trays through the first and second traysealing tools is in opposite directions.

The traysealing apparatus of the present invention overcomes the above problems by providing a single traysealing machine which comprises first and second traysealing tools. The use of a single unitary machine advantageously reduces the amount of factory floor space taken up by a food production line where trays are to be sealed by two sealing processes (typically a skin seal followed by a top seal). In order to allow a single traysealing machine to be used, the first and second traysealing tools are located side by side, meaning that they are laterally adjacent each other. Further, in use the movement of the trays through the first and second traysealing tools is in opposite directions. For example, trays may move through the first traysealing tool from "right to left", meaning that they approach the first traysealing tool on the first infeed lane located to the right of the traysealing tool and exit the first traysealing tool having been subjected to the first traysealing process on the first outfeed lane located to the left of the tool.

The trays which have now been subjected to the first traysealing process subsequently move through the second traysealing tool in the opposite direction, i.e. "left to right". Therefore, the second infeed lane is located to the left of the second traysealing tool and the second outfeed lane is located to the right of the second traysealing tool.

As the first and second traysealing tools are located side by side, typically the first outfeed lane and the second infeed lane are located side by side. Alternatively or in addition, the first infeed lane and second outfeed lane are located side by side. Conventionally, the first and second traysealing tools are elongate and thus each of the infeed and outfeed lanes are typically linear and parallel. Such a configuration provides a compact traysealing apparatus having a small factory floor footprint. Other configurations and geometries are envisaged however, for example curved infeed and/or outfeed lanes.

Furthermore, it is envisaged that in one arrangement the infeed and/or outfeed lanes are not side by side, dependent on the requirements of the food packaging line. For example, the first infeed lane may transfer trays from a batching table and approach the traysealing machine at a first angle, and the second outfeed lane may transport trays away from the traysealing machine to a labelling station, at a second angle such that the first infeed lane and second outfeed lane are not parallel. However, as the first and second traysealing tools themselves are located side by side, the overall factory floor footprint is advantageously small, and both sealing processes occur in a compact and easily monitored space.

Preferably, a "U" shaped conveyor is used to transport trays from the first outfeed lane to the second infeed lane. This is particularly advantageous in the preferred configuration when the first outfeed lane and second infeed lane are side by side and parallel. Even so, such a "U" shaped conveyor may be used to transfer trays appropriately even when the first outfeed lane and second infeed lane are not side by side and parallel. In such an arrangement, it will be understood by the skilled person that the term "U shaped conveyor" includes any geometry of conveyor that transfers trays from the first outfeed lane to the second infeed lane. In some arrangements, the "U" shaped conveyor is an integral part of either the first outfeed conveyor or the second infeed conveyor. Other ways of transferring the trays from the first outfeed conveyor to the second infeed conveyor are envisaged, such as a cross pusher and/or walking beam. These examples find particular use when the first outfeed and second infeed lanes are side by side and preferably parallel. As discussed above, preferably the first traysealing process is a skin sealing process operable to apply a skin seal to the content of the trays, such as foodstuff, and the second traysealing process is a top seal process adapted to apply a top seal to the trays. However, the traysealing tools may be operable to perform different sealing processes known in the art.

Brief Description of the Drawings

The invention will now be described with relation to the following drawing, in which:

Figure 1 is a schematic illustration of a traysealing apparatus according to a first embodiment of the invention, in plan form.

Figures 2A to 2G are schematic illustration of a traysealing apparatus according to a second embodiment of the invention, in plan form.

Detailed Description of the Drawings Figure 1 is a schematic illustration of a traysealing apparatus 100 in plan form. The apparatus 100 comprises a traysealing machine 10 which further comprises first (1 1 ) and second (13) traysealing tools depicted by the dashed lines. The first and second traysealing tools are located side by side and are both housed within an outer frame 14 of the traysealing machine 10. This advantageously means that all cabling (for electronics, pneumatics etc.) only needs to be routed to a single machine rather than two separate tools as in the prior art.

The apparatus 100 further comprises a first infeed lane 1 which is operable to transport trays to be sealed (shown at 20) in the direction of arrow A to the first traysealing tool 1 1. Typically, in practice, trays will be packaged with food product by operators at a batching table and placed on a conveyor leading to the first infeed lane 1. A first gripper arm (not shown) transfers trays from the first infeed lane 1 onto a lower tool half of the first traysealing tool 1 1. The trays are spaced at a predetermined pitch corresponding to the tool being used. Figure 1 shows two trays (spaced at a pitch P) being sealed simultaneously by the first traysealing tool 1 1 , although it will be appreciated that more than two trays may be sealed at the same time depending on the tool used. In the present example, the first traysealing tool 1 1 is a skin sealing tool. During the sealing process, the lower tool half of the tool is raised towards an upper tool half of the tool where the plastic film is applied to food product in the trays. Trays which have been subjected to the skin sealing process are shown at 22 and schematically illustrated with a single diagonal line. These trays which have been subjected to the skin sealing process are then transferred by the first gripper arm from the first traysealing tool 1 1 and onto a first outfeed lane 3 which runs in the direction of arrow A.

The trays 22 are transported by the first outfeed lane 3 onto U-shaped conveyor 9. The U-shaped conveyor transports the trays through a 180° change of direction (illustrated by arrow C) onto second infeed lane 5 which transports the trays in the direction of arrow B. In the present example, the first outfeed lane 3 and second infeed lane 5 are located side by side and run in substantially opposite directions (i.e. directions A and B are at 180° to each other). The presence of the first outfeed lane 3 and second infeed lane 5 creates a "buffer" between the first and second traysealing tools which increases each tool's efficiency and allows the machines to run independently. Therefore a small delay on the first machine will not delay the start of the second machine's cycle. Alternatively if the second machine has a delay the first machine can continue to feed trays into the buffer provided between it and the second machine.

A second gripper arm (not shown) then transfers the trays 22 from the second infeed lane 5 onto a lower tool half of the second traysealing tool 13. In the present example the trays are spaced on the lower tool half of the second traysealing tool at the same predetermined pitch P as for the first traysealing tool. However, it will be appreciated that a different spacing of trays may be used depending on the requirements of the first and second traysealing tools. Typically, the trays are not maintained at the same pitch along each of the infeed and outfeed lanes and U-shaped conveyor of the apparatus 100 so that these areas can act as a buffer.

In the present example, the second traysealing tool 13 is a top seal tool and during the sealing process, the lower tool half of the top seal tool is raised towards an upper tool half where the top seal is applied to flanges of the trays. The gripper tool then transfers the sealed trays onto second outfeed conveyor 7 which runs in the direction of arrow B. In the present example, the first infeed lane and second outfeed lane are located side by side and run in substantially opposing directions A and B respectively.

The trays which have been subjected to both the skin seal and top seal processes are schematically illustrated at 24 and depicted by two diagonal lines. These trays 24 are then conveyed to further apparatus of the food packaging line, such as quality control and/or labelling tools (not shown).

Figures 2A to 2F show an alternative transfer means to the U-shaped conveyor 9 of the embodiment of Figure 1. In this embodiment, the transfer means comprises a cross pusher 31 , operating in conjunction with the walking beams or gripper arms 32, 33 of Figure 1 (although the gripper arms are not shown in Figure 1 ). A first gripper arm 32 is located, in a first position, longitudinally alongside the first traysealing tool 1 1. The length of the first gripper arm 32 is such that, in the first position, it extends along the length of the first traysealing tool 1 1 and part of the first infeed lane. The first gripper 32 arm is further connected to control means (not shown) capable of moving the gripper arm longitudinally to a second position, alongside the first traysealing tool 1 1 and part of the first outfeed lane 3. The gripper arm 32 is also movable, while in both the first and second positions, transversely into and out of the first traysealing tool and first infeed/outfeed lane. A second gripper arm 33 is arranged in a similar manner with respect the second traysealing tool 13, second infeed lane 5, and second outfeed lane 7. Each gripper arm 32, 33 also has indents (not shown in Figure 2A) into which respective trays are received in use. A cross pusher 31 is located longitudinally alongside the first outfeed lane 3, and is connected to a control means (not shown) capable of moving it transversely across the first outfeed lane and partially into the second infeed lane.

Figure 2A shows the traysealing tools 1 1 , 13 immediately after executing their respective sealing processes, in which the lower tool halves of both tools are raised towards repective upper tool halves. After the sealing process in completed, the lower tool half of the traysealing tool 11 , 13 is lowered, and the trays 22, 24 may be accessed by their respective gripper arms 32, 33. The first sealing tool 1 1 contains four skin sealed trays 22 ready to be moved out of the first traysealing tool, and the first infeed lane 1 contains 4 open trays 20, ready to be moved to the first traysealing tool 1 1. As shown in the transition between Figures 2A and 2B, a first gripper arm 32 moves horizontally, perpendicular to the direction of travel A of the first infeed and outfeed lanes 1 , 3, to collect both sets of trays 20, 22 in the respective indents on the gripper arm. As shown in Figure 2C, the first gripper arm them moves parallel to, and in the direction of travel A of the first infeed and outfeed lanes 1 , 3, thereby moving the skin sealed trays 22 into the first outfeed lane 3, and moving the open trays 20 into the first traysealing tool 1 1.

As shown in Figure 2D, the cross pusher 31 then moves horizontally, perpendicular to the direction of travel A of the first infeed and outfeed lanes 1 , 3, over the top of the first gripper arm 32, thereby pushing the skin sealed trays (parts of which extend above the gripper arm) from the first outfeed lane 3 to the second infeed lane 5. The first gripper arm 32 then moves transversely, out of the first outfeed lane 3 and the first traysealing tool 11 , leaving the open trays 20 in the first tray sealing tool 1 1. The gripper arm 32 then moves longitudinally back to its starting position, ready to collect another set of trays.

As shown in Figure 2E, once the lower tool half of the second traysealing tool 13 is lowered, a second gripper arm 33 moves horizontally, perpendicular to the direction of travel B of the second infeed and outfeed lanes 5, 7 to collect both the skin sealed trays 22 in the second infeed lane 5, and the top sealed trays 24 in the second traysealing tool 13. As shown in Figure 2F, the second gripper arm 33 then moves parallel to and in the direction of travel B of the second infeed and outfeed lanes 5, 7, thereby moving the skin sealed trays 22 into the second traysealing tool 13, and the top sealed trays 24 into the second outfeed lane 7. Then, the second gripper arm 33 moves horizontally back out of the second sealing tool 13, leaving the skin sealed trays in the second sealing tool 13 and the top sealed trays on the second outfeed lane 7, before returning to its first position ready to collect another set of trays.

While the operation of the transfer means is discussed sequentially, step by step, it will be appreciated that execution of a number of these steps may overlap or occur simultaneously. For example, the first and second gripper arms 32, 33 may simultaneously operate to move their respective trays.

Additional embodiments are also foreseen in which the cross pusher 31 is positioned alongside the first outfeed lane 3 at a greater distance from the traysealing machine 10, so that the first outfeed and second infeed lane may act as a buffer between the first and second traysealing tools 1 1 , 13.

Claims

1. A traysealing apparatus comprising;

a traysealing machine comprising first and second traysealing tools operable to perform respective first and second traysealing processes on trays to be sealed, wherein the first and second traysealing tools are located side by side;

first and second infeed lanes and first and second outfeed lanes for transferring trays to and away from their respective traysealing tool; and,

transfer means for transferring trays that have been subjected to the first sealing process from the first outfeed lane to the second infeed lane, wherein; in use the movement of trays through the first and second traysealing tools is in opposite directions.

2. The traysealing apparatus of claim 1 , wherein the first outfeed lane and the second infeed lane are located side by side.

3. The traysealing apparatus of claim 1 or claim 2, wherein the first infeed lane and the second outfeed lane are located side by side.

4. The traysealing apparatus of any of the preceding claims, wherein the first traysealing process is a skin seal process.

5. The traysealing apparatus of any of the preceding claims, wherein the second traysealing process is a top seal process.

6. The traysealing apparatus of any of the preceding claims, wherein the transfer means is a U-shaped conveyor.

7. The traysealing apparatus of any claims 1 to 5, wherein the transfer means comprises a cross pusher.

8. The traysealing apparatus of any of claims 1 to 5, wherein the transfer means comprises a walking beam or gripper arm.

9. The traysealing apparatus of any of the preceding claims, wherein the speeds of one or more of the first outfeed lane, transfer means and/or the second infeed lane are selectable so as to provide a buffer between the first traysealing tool and the second traysealing tool.

10. A food packaging system comprising a traysealing apparatus according to any of the preceding claims.