Automated bag handling

Abstract

An apparatus and method for automatically handling vest-type bags in the context of an automated packing process for packing items such as groceries are described. The apparatus includes at least two fingers that extend parallel to one another, and are arranged to move apart to increase the spacing between the fingers along a bag-opening direction. The fingers are inserted between the strips of the handle, and then moved apart in the bag-opening direction to part the strips of the handle in the bag-opening direction. A packing process involving automated bag handling operations is also inclosed.

Claims

1. Apparatus for automatically handling vest-type bags of an automated packing process, the bags including two handles, each handle being formed as a loop with two strips joined at one end of each handle, the apparatus comprising: two finger pairs, each finger pair being associated with one of the two handles, each finger within the finger pairs extending parallel to one another, said fingers within the finger pairs being arranged to move apart to increase a spacing between the fingers along a bag-opening direction, wherein the apparatus is configured to insert a finger pair between strips of each handle, and to move the fingers apart in the bag-opening direction to part the strips of the handle in the bag-opening direction; and at least one push plate for insertion into a loop of a respective handle, the push plate being moveable away from the fingers in a direction substantially perpendicular to the bag-opening direction so as to tension the handles and constrain the side portions in the bag-opening direction.

2. The apparatus of claim 1, comprising: suction means configured for engaging each strip of the handle, wherein the suction means is configured to grip each strip of the handle so as to part the strips before the fingers of each finger pair are inserted.

3. The apparatus of claim 1, wherein the apparatus is configured to manipulate vest-type bags having two sheets of film-like material and having a non-rigid form.

4. The apparatus of claim 3, wherein the apparatus is configured to insert the fingers of each finger pair when a bag is in a closed configuration where the two sheets are substantially adjacent each other and the bag is unable to receive items, and to separate the fingers of each finger pair to place the bag in an open configuration where the two sheets are substantially separated and the bag is open to receive items.

5. The apparatus of claim 1, wherein via the at least one push plate for insertion into a loop of a respective handle the apparatus is configured to impart a temporary rigidity to an opened bag to enable automated manipulation of the opened bag.

6. The apparatus of claim 1, wherein the fingers of each finger pair are moveable between a first position in which the fingers of each finger pair are to be inserted into the handle, and a second position in which the fingers of each finger pair will pull the loop of the handle outwards from a respective bag.

7. The apparatus of claim 6, wherein the first position is substantially perpendicular to the second position.

8. The apparatus of claim 6, wherein the first position is a generally horizontal position, and the second position is a generally vertical position.

9. The apparatus of claim 6, wherein the fingers of each finger pair are pivotable between the first and second positions about an axis that extends substantially parallel to the bag opening direction.

10. The apparatus of claim 9, comprising: a carriage having a pivotable part to which the fingers of each finger pair are mounted.

11. The apparatus of claim 10, wherein the carriage comprises: a roller connected to the pivotable part and cooperable with a cam track of a guide component of the apparatus, the cam track being arranged such that movement of the carriage along the guide component will cause pivoting of the fingers of each finger pair from the first position to the second position.

12. The apparatus of claim 6, wherein the apparatus is configured to lower the bag towards a container by downward motion of the fingers of each finger pair, with movement of the fingers from the first position to the second position is being driven by the downward motion.

13. The apparatus of claim 6, wherein the at least one push plate is configured to be inserted into the loop of a respective handle and moved away from the fingers when the fingers of each finger pair are in the second position.

14. The apparatus of claim 1, comprising: means for tensioning the handle and constraining side portions of the handle in the bag-opening direction.

15. The apparatus of claim 1, wherein the apparatus is configured to place an open bag in a container configured to support the bag in an opened configuration.

16. The apparatus of claim 15, wherein the apparatus is configured to insert side portions of the at least one handle into respective recesses defined in the container.

17. The apparatus of claim 1, comprising: a frame having first and second upstanding legs spaced apart to define a bag-receiving zone in between; a first pair of fingers mounted to the first leg; and a second pair of fingers mounted to the second leg, the legs being configured to pivot about respective axes that extend substantially parallel to the bag-opening direction so as to move the legs inwardly and outwardly with respect to a bag, and wherein inward movement of the legs causes the respective pairs of fingers each to be inserted between the strips of a respective handle of the bag.

18. A packing line for packing items into vest-type bags, the packing line comprising: the automated bag-handling apparatus of claim 1.

19. A packing facility comprising: the packing line of claim 18.

20. An automated method of handling vest-type bags in an automated packing process, the bags including two handles formed as a loop with two strips joined at one end of the handle, the method comprising: inserting a finger pair including two fingers of an automated bag-handling apparatus between the strips of each handle; moving the fingers within the finger pair apart in a bag-opening direction to part the strips of each handle in the bag-opening direction; and inserting a push plate into the loop of the handles and moving the push plate away from the fingers of each finger pair in a direction substantially perpendicular to the bag-opening direction so as to pull the handles taut and constrain side portions of the handles in the bag-opening direction.

21. The method of claim 20, comprising: parting the strips of the handle by suction before the fingers of each finger pair are inserted between the strips.

22. The method of claim 20, comprising: imparting temporary rigidity to an opened bag by means of the fingers of each finger pair to enable automated manipulation of the bag.

23. The method of claim 20 comprising: moving the fingers of each finger pair from a first position to a second position so as to pull a loop of the respective handle outwards from the bag.

24. The method of claim 23, wherein the first position is substantially perpendicular to the second position.

25. The method of claim 23, wherein the first position is a generally horizontal position, and the second position is a generally vertical position.

26. The method of claim 23, wherein moving the fingers of each finger pair between the first and second positions comprises: turning the fingers of each finger pair about an axis that extends substantially parallel to the bag opening direction.

27. The method of claim 23, comprising: lowering an open bag into a container by moving the fingers of each finger pair in a downwards direction, wherein the downward motion of the fingers of each finger pair drives the movement of the fingers of each finger pair from the first to the second position via a cam mechanism.

28. The method of claim 23, comprising: inserting the push plate into the loop of a respective handle when the fingers of each finger pair are in the second position.

29. The method of claim 20, comprising: placing the bag in a container configured to support the bag in an opened configuration.

30. The method of claim 29 comprising: inserting the constrained side portions of the at least one handle into respective recesses defined in the container.

31. The method of claim 29 comprising: releasing the bag from the handling apparatus by moving the fingers of each finger pair together and moving the fingers further in a downwards direction.

32. The method of claim 20, comprising: supporting the bag in a bag-receiving zone defined between first and second pairs of fingers and moving the fingers of each finger pair inwardly with respect to the bag so as to insert respective pairs of fingers between the strips of a respective handle of the bag.

33. A method of packing items into vest-type bags, the method comprising: automatically handling vest-type bags according to the method of claim 20.

34. The method-of claim 33, wherein items are packed into vest-type bags within a packing facility.

35. A method of packing items into vest-type bags, the method comprising: (a) providing an automated bag handling apparatus, the bag handling apparatus including finger pairs, wherein each finger pair includes two fingers and the fingers of each finger pair are configured to be inserted into a respective handle of the bag; (b) continuously supplying vest-type bags to the automated bag handling apparatus, the bags being supplied empty and in a closed configuration, each bag including two handles wherein each handle is formed as a loop, the loop includes two strips joined at one end of the respective handle, and the fingers within the finger pairs of the handling apparatus is arranged to move apart in a bag opening direction to part the strips of each handle; and (c) successively supplying containers to the automated bag handling apparatus, the containers being configured to support the vest-type bags in an open configuration; wherein the automated bag handling apparatus is configured to perform the following operations on each bag in turn: (i) automatically open the bag; and (ii) automatically place the opened bag in a respective container such that the respective container supports the bag in an open configuration; the method comprising: (d) moving the respective container including the supported opened bag to a packing station or between a plurality of packing stations; (e) adding one or more items to the opened bag at the or each packing station whilst the bag is supported inside the respective container; (f) removing the bag containing the one or more items from the respective container; and (g) inserting a push plate into the loop of each handle and moving the push plate in a direction substantially perpendicular to the bag-opening direction so as to pull the handles taut and constrain side portions of the handles in the bag-opening direction.

36. The method of claim 35, wherein the automated bag handling apparatus comprises: inserting the fingers of each finger pair of the automated bag-handling apparatus between the strips of the respective handle; and moving the fingers apart in the bag-opening direction to part the strips of the respective handle in the bag-opening direction.

37. The method of claim 35, wherein the automated bag handling apparatus is configured to perform-operations (i) and (ii) by: inserting the fingers of each finger pair of the automated bag-handling apparatus between the strips of the respective handle; and moving the fingers apart in the bag-opening direction to part the strips of the respective handle in the bag-opening direction.

38. The method of claim 35, comprising: automatically placing a plurality of bags into the same container before step (d).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

(2) FIG. 1 is a schematic illustration of a vest-type carrier bag;

(3) FIGS. 2(a) and 2(b) provide a schematic illustration of a container or tote for holding bags of the type shown in FIG. 1;

(4) FIGS. 3, 4 and 5 are schematic side, top and front views respectively of a bag handling apparatus according to an embodiment of the invention, illustrating a sequence of steps in a bag opening and placing operation;

(5) FIGS. 6(a) and 6(b) are schematic top views of part of a bag opening device of the bag handling apparatus of FIGS. 3 to 5;

(6) FIG. 7 is a more detailed view of the bag handling apparatus of FIGS. 3 to 5;

(7) FIG. 8 is a side view of a guide component of the bag handling apparatus of FIGS. 3 to 5;

(8) FIG. 9 is a perspective view of part of the bag handling apparatus of FIGS. 3 to 5;

(9) FIG. 10 shows schematic side views of the bag handling apparatus of FIGS. 3 to 5, to illustrate a sequence of further steps in the bag opening and placing operation;

(10) FIG. 11 is a schematic top view of the bag handling apparatus of FIGS. 3 to 5 illustrating one step in the bag opening and placing operation; and

(11) FIGS. 12(a) and 12(b) are schematic side and top views respectively of the bag handling apparatus of FIGS. 3 to 5, illustrating a further step in the bag opening and placing operation.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

(12) FIG. 1 shows an example of a vest-type carrier bag 10. The bag 10 is made from two thin layers of plastics film. In a generally rectangular body portion 12 of the bag, the layers are joined along two opposite sides and the bottom of the body portion 12 and are not joined along the top of the body portion 12, to define an open-topped volume for receiving and holding goods when the film layers are spaced apart in use. Two handles 14, one on each side, extend away from the open top of the body portion 12. Each handle 14 is formed by joining the film layers only along their top edge, allowing the film layers to be parted so that the handles 14 form loops.

(13) In the present embodiment, vest-type bags 10 of the type shown in FIG. 1 are supplied flat on a roll for use in an automated, industrial-scale process forming part of a system for fulfilling orders in a grocery retail operation. The present embodiment provides apparatus for opening the bag 10 by separating the two layers of film that form each handle 14, and pulling the layers apart to open the body portion 12 of the bag 10. The apparatus also places the opened bag 10 in a container or tote to allow subsequent filling of the bag to satisfy a customer order.

(14) The benefit of using a vest-type bag 10 is that not only can it subsequently be used for carrying the bag as part of the delivery to the customer, but also that it allows the bag 10 to be securely placed and held in a container and thus facilitate the picking and packing of product in an order picking system. FIG. 2(a) shows an example of an order picking container 16, known as a tote, having an open top and rigid side walls 18 and base. This type of container 16 is instrumental for moving goods around in a large order picking operation, since the containers 16 can be transported on automated conveyor systems and the like. The container 16 may be equipped with keyhole-shaped slits 20 at the top of the side walls 18 for holding each bag 10 open and in place within the container 16. FIG. 2(b) shows the detail of a slit 20.

(15) The present embodiment includes a device for inserting vest-type bags 10 of the type shown in FIG. 1 into containers 16 of the type shown in FIG. 2(a), by means of mechanical fingers 22, as will be explained with reference first to FIGS. 3 to 5.

(16) The process starts with one carrier bag 10 being dispensed from a roll into a location in which four suction cups 24 of a suction device are applied to the handles 14 to separate the layers of film in each handle 14, as shown as Step 1 in FIGS. 3 and 4. The bags may alternatively be dispensed from a stack of flat bags provided and for one bag at a time to be dispensed to the apparatus by a bag dispensing mechanism (not shown). The suction cups 24 are arranged either side of a vertical plane, referred to hereafter as the bag plane. A container or tote 16 is moved into position beneath the bag 10.

(17) The suction cups 24 pull the handles 14 slightly open in a direction perpendicular to the bag plane, known hereafter as the bag opening direction, and the body portion 12 of the bag 10 hangs generally vertically downwards from the handles 14.

(18) Once the handles 14 are opened by the suction device, it is necessary to gain positive mechanical control of the handles 14, in order to open the bags 10 and position them to the intended location.

(19) In the present embodiment, this is achieved by means of fingers 22, which are inserted into the opened handle 14 (namely between the two pulled-apart portions of the bag handles) and then moved apart to gain full and positive mechanical control of the bag 10. Referring additionally to FIG. 6(a), in one possible embodiment the fingers 22 comprise elongate bar-like members that extend horizontally inwards from a frame 26 in a direction parallel to the bag plane and perpendicular to the bag opening direction. Four fingers 22 are present in total, and the fingers 22 are arranged in two pairs that oppose one another across the frame (only one pair of fingers 22 is shown in FIG. 6(a)). The fingers 22 are arranged to slide together and apart from one another in the bag opening direction. The inside end 28 of each finger 22 is shaped so that, when the two fingers 22 of a pair come together as shown in FIG. 6(b), they form a pointed shape (pointed in the direction of insertion) for easy insertion between the handles 14 of the bag 10.

(20) As shown in Step 2 in FIGS. 3 and 4, each pair of fingers 22 is inserted into the loop formed by the respective handle 14 of the bag 10. The inward movement of the fingers 22 is achieved by movement of the frame 26, as will now be explained.

(21) FIG. 7 is a front view of the apparatus together with a bag 10 and a container 16, and with the suction device and other features omitted for clarity. The frame 26 comprises upstanding legs 30 that are able to pivot at their respective bases 32 about axes that lie parallel to the bag opening direction and either side of the container 16. The fingers 22 are mounted on carriages 34 that can move up and down in a vertical direction with respect to each leg 30. The legs 30 can be rotated about the pivots in planes parallel to the bag plane (i.e. parallel to the plane of FIG. 7) to move inwardly and outwardly with respect to the bag 10.

(22) When the bag 10 is moved into position, the legs 30 are held in a retracted position, so that the tops of the legs 30 are splayed outwardly (not shown). In Step 2 of the process, the legs 30 are moved inwards by actuators 36 into the position shown in FIG. 7, to push the fingers 22 into the loops of the handles 14. The suction cups 24 are then withdrawn, so that the bag 10 hangs from the fingers 22.

(23) In Step 3, each pair of fingers 22 is separated to stretch the handles 14 open. The fingers 22 move apart in the bag opening direction, into the configuration shown in FIG. 6(b). Each finger 22 includes a hook-like formation 38 to help positively locate and retain the bag handle 14 on the finger 22 and to guard against the handle 14 slipping off the fingers 22.

(24) Referring back to FIGS. 3 to 5, In Step 4, the bag 10, held by fingers 22 on both sides, is lowered towards the container 16. As this happens, each pair of fingers 22 is rotated through approximately 90 degrees about a respective pivot axis 40 that extends parallel to the bag opening direction. In this way, the fingers 22 move into a generally vertical or upright configuration.

(25) The fingers 22 move into the upright configuration automatically as the carriage 34 moves downwards. Any suitable means can be used to achieve this action. In one embodiment of the invention, movement of the fingers 22 is controlled using a cam mechanism driven by the downwards motion of the carriage 34. An example of a suitable cam mechanism is shown in FIGS. 8 and 9. A guide component 42, shown most clearly in FIG. 8, is positioned vertically along each leg 30 of the frame. The guide component 42 has a cam track 44 for guiding a roller 46 along a path having an upper generally vertical portion 44a and a lower generally vertical portion 44b. The upper and lower vertical portions 44a, 44b are linked by an intermediate portion 44c of the track 44 that extends at an angle to the vertical. The upper and lower portions 44a, 44b are offset so that the upper portion 44a is closer to the bag 10 than the lower portion 44b.

(26) As shown in FIG. 9, the roller 46 engages with the cam track 44. The roller 46 is mounted on the carriage 34, and is connected by links to a plate 48 on which the fingers (not shown in FIG. 9) are mounted. The plate 48 can pivot about an axis that extends in the bag opening direction. The roller 46 is connected to a driveshaft 50 by way of a link 52, so that the driveshaft 50 is driven in a turning movement as the roller 46 moves down the cam track 44. The driveshaft 50 is mounted in a fixed portion of the carriage 34, which is driven in vertical movement by suitable actuators (not shown).

(27) Further links 54, 56 connect the end of the driveshaft 50 opposite the roller 46 to the plate 48, so that turning movement of the driveshaft 50 causes the plate 48 to move from a horizontal orientation to a vertical orientation as the roller 46 moves downwards along the cam track 44. One pair of fingers 22, and the associated mechanism that moves the fingers 22 together and apart, are mounted on and generally parallel to the plate 48, so that the downward movement of the carriage 34 causes the fingers 22 to move into their upright configuration. FIG. 9 shows the cam mechanism used on the left-hand, rear side of the apparatus as oriented in FIG. 7, and the driveshaft 50 moves anticlockwise as the carriage 34 moves downwards to rotate the left-hand pair of fingers 22 to the upright position. A corresponding mirror image cam mechanism (not shown) is also provided on the right-hand rear side of the apparatus of FIG. 7.

(28) Once the fingers 22 have moved into the upright position in Step 4, the handles 14 are then manipulated to stretch them fully open ready to engage with the container 16. This is useful as the rotation of the fingers moves the handles into a position at which one side edge 57a of the handle 14 will be relatively taut and the other side edge 57b will be relatively slack. So, in Step 5 (see FIGS. 4 and 5), push plates 58 are inserted into the gaps in the handles 14 created by the fingers 22. The push plates 58 are then pushed inwardly towards one another to stretch the handles 14 into a fully open configuration, namely to make the edge 57a of the handles 14 which has some relative slack to become taut. Details of the push plate operation 58 are shown in FIGS. 10 and 11, which show the left-hand-side handle 14 of the bag 10. The push plate 58 is a generally rectangular plate which is tilted into a vertical position within the loop of the handle 14 by a suitable mechanism. The handle 14 is held open by the fingers 22 to allow access for the push plate 58. The push plate 58 is then pushed sideways (perpendicular to the bag opening direction) to stretch the handle 14, to ensure both side edges 57 of the handle are relatively taut.

(29) In this position, the plastic film of the handle 14 is fully stretched into a generally rectangular shape and held in a precisely defined position, as shown in the top view of FIG. 11. It will be appreciated that the push plates 58 ensure that side portions 59 of the handles 14 are suitably taut and constrained in the bag-opening direction in order to facilitate their insertion into the slits 20 in the rim of the container 16, as will now be explained.

(30) Referring back to FIG. 5, with the bag 10 now fully controlled by the fingers 22 and push plates 58, in Step 6 the bag 10 is lowered into the container 16 in a way which pushes the side portions 59 of the handles 14 into the slits 20, as shown in FIGS. 12(a) and 12(b). The fingers 22 remain outside the side walls 18 of the container 16, while the push plates 58 are lowered a short distance into the inside of the container 16. In this way, the side portions 59 of the handles 14 are guided into the slits 20 in the rim of the container 16.

(31) In Step 7, when the bag 10 is positioned in the container 16, with the handles 14 engaged with the slits 20 in the container 16, the push plates 58 are lifted and withdrawn and the fingers 22 are moved together in the reverse of the bag opening direction, to disengage the fingers 22 from the handles 14. The fingers 22 are then lowered further to disengage fully the apparatus from the container 16. The bag 10 is now fully inserted into a defined and secure location in the container 16.

(32) In Step 8 of the process (not illustrated), the container 16 is then moved on by means of a conveyor belt, and is replaced by another empty container 16. The legs 30 of the frame are moved outwards and the carriages 34 moved upwards to return the apparatus to its starting position, and the process described above is then repeated to place a bag 10 into the new container 16.

(33) The apparatus may be configured to place multiple bags into each container 16. A first bag 10 is placed at a first location in the container, and the container 16 may then be indexed to another position, to insert a second bag 10 at a second location in the same container. The steps above are then repeated to place further bags in the container. In the present embodiment, four pairs of slits 20 are provided on the rim of the container 16 which permits three bags 10 to be held within the current container 16 as adjacent bags share the same slit in the container. However, the container and the process could readily be designed to hold greater or fewer numbers of bags as required. The automated nature of the bagging process of the present embodiment enables a bagging rate of ten bags per minute to be accurately handled by the apparatus.