GB2074127A - Package handling - Google Patents

Abstract

A packet handling device operable to pick up and place a packet 24, comprises a suction pick-up member 8 depending via a longitudinal lost motion connection 11 from a vertically mountable and operable piston and cylinder 4. The device is incorporated in packing apparatus for movement between pick-up and deposit points, means being provided for repeatedly effecting the said movement and operating the suction pick-up member and piston and cylinder according to a predetermined programme for the sequential pick up of a packet from one point and its transport to and deposit at another; for example, a plurality of the devices may be connected to a vertical central drive shaft by radial arms (preferably extendible and retractable) for incremental rotation by and in a circuit about the drive shaft. <IMAGE>

Description

SPECIFICATION Package handling The present invention relates to the filling of packets or pouches and the like into trays, boxes and like receptacles. Heretofore, this operation has generally been performed manually, thus being inefficient and labour-intensive and contributing appreciably to the production cost of the packed guods. Machines for the purpose have been complex and of high capital and maintenance costs.

The present invention provides a packet handling device operable to pick up and place a packet, the device comprising a suction pick-up member depending via a longitudinal lost motion connection from a vertically mountable and operable piston and cylinder. The device will usually be incorporated in packing apparatus comprising such a device mounted vertically for movement (e.g. in a full or partial circuit) between pick-up and deposit points, means being provided for intermittently effecting the said movement and operating the suction pick-up member and piston and cylinder according to a predetermined programme for the sequential pick up of a packet from a pick-up point and its transport to and deposit at a deposit point; for example, the packet handling device may be radially spaced from and connected to a vertical central drive shaft for rotation by and in a circuit about the drive shaft.

Preferably, a plurality of such packet handling devices will be so mounted, e.g. circumferentially spaced around a circuit, each for movement along the circuit between pick-up and deposit points.

Preferably the or each packet handling device repeated by moves incrementally through a full 3600 circuit in operation of the apparatus, through arrangements are possible in which the or each packet handling device reciprocates between pickup and deposit points.

In operation a packet handling device is moved, e.g. rotated, to a pick-up point where a packet has been located, and its piston and cylinder are operated to lower the pick-up member onto the packet; the lost motion connection allows the pick-up member to halt on contact with the packet before the end of the downward piston/cylinder stroke, so that delicate packets can be handled without damage and packets of different size can be handled without adjustment of the device.The pick-up member preferably contacts the packet resiliently, e.g. by way of a resilient pad or pads, this further decreasing the risk of packet damage, and on or before this contact the suction is applied to secure the member and packet together and is maintained whilst the piston and cylinder are operated to raise the packet, the device is moved, e.g. rotated, to a deposit point, and the piston and cylinder are there coerated to deposit the packet; on deposition, the lost motion connection between the pick-up member and piston/cylinder again prevents damage to the packet being handled, and also permits packets to be deposited in different layers without adjustment of the device. When the packet has been deposited, the suction is switched off, the pick-up member raised, and the device moved, e.g. rotated, to the said or another pick-up position to collect another packet.Preferably, one packet handling device will be at a pick-up point whilst another is at a deposit point, so that one packet is picked up whilst another is deposited.

The suction pick-up member usually comprises a plate or frame carrying at least one downwardly directed suction nozzle attached to a suction line, the plate or frame also carrying a resiliently deformable pad or pads extending downwardly beyond the suction nozzle or nozzles for resilient contact with a packet or pouch during operation.

The resiliently deformable pad or pads (e.g. of sponge rubber or foamed plastics) will preferably be resiliently compressible, under the weight applied when the pick-up member rests on a package or pouch, to permit contact between the suction nozzle or nozzles and the package or pouch surface. Preferably, a resiliently deformable pad is spaced from and extends in a complete circuit around the suction nozzle or nozzles (which may also project downwardly from the plate or frame), for example forming around the nozzle or nozzles an elliptical or circular wall or one which is generally rectangular with at least one pair of opposed sides rounded.The provision of the suction nozzle or nozzles within a surrounding resiliently deformable wall projecting downwardly beyond the nozzle or nozzles can optimise the positive engagement between the suction pick-up member and packet or pouch during operation.

The lost motion connection between the pick-up member and its piston and cylinder may be effected in a number of ways. For example, the piston or cylinder may be connected to the pick-up member by at least one connector which folds or flexes to take up the continued downward movement of the piston or cylinder when downward movement of the member is arrested; such connectors include lazy tongs, other pivoted arm structures, flexible linkages etc. In another type of arrangement, the pick-up member is suspended by at least one rod or tubular member from a plate or frame rigidly attached to the moving cylinder or piston, the rod(s) or tube(s) being telescopic or passing freely through the body of the plate or frame to provide for the said lost motion.The pick-up member, together with the adjacent portion of the lost motion connection, should be of sufficient weight to extend the lost motion connection to its full length under gravity - and, as mentioned above, preferably also to compress a resiliently deformable pad or pads on the pick-up member when resting on a packet or pouch sufficiently to permit contact between the packet or pouch and a suction nozzle or nozzles of the pick-up member.

Once the pick-up member comes to rest in its pick-up or deposition operation, continued downward movement of the piston or cylinder involves wastage of useful time -- doubly so, since the return stroke also involves taking up of the lost motion before the pick-up member is raised. In order to reduce such wastage, it is preferred to provide the packet handling device with a switch for automatically curtailing the downward stroke of the piston or cylinder shortly after the pick-up member comes to rest.For example a switch member mounted on the moving piston or cylinder may contact another on the lost motion connection on continued downward movement of the piston or cylinder shortly after the pick-up member comes to rest, such contact operating a switch to stop and then reverse the piston and cylinder stroke; alternatively, a contact might be broken in like manner to effect the stroke reversal. In this way, safe handling of the packets or pouches due to the lost motion connection can be maintained whilst minimising the amount of time wastage due to the lost motion. Such a switch may also be programmed to control the application and release of suction by the pick-up member.

The packets or pouches are conveniently fed to the pick-up point on a smooth band conveyor, a stop member being disposed to arrest the packets as they arrive at the predetermined pick-up point with the conveyor then slipping beneath them; the stop is preferably adjustable longitudinally of the conveyor so that different size packets can be located accurately at the pick-up point for correct engagement with the pick-up member of the packet handling device.

In the simplest case, packets or pouches fed in single file to the pick-up point are deposited in a corresponding single line in a receptacle advanced intermittently through the deposit point; the receptacle is advanced an appropriate distance after each deposit. Where the packets or pouches are to be deposited in the receptacle in two or more layers, then the bottom layer will be completed first, and the receptacle then reversed to its original position for deposition in similar fashion of the second layer, and soon.

Alternatively, the receptacle can be advanced intermittently through the deposit point for the deposition of one layer, and then reversed intermittently through the deposit point for deposition of the second, and so on. It is possible to pick up a plurality of packets or pouches simultaneously from the single line at the pick-up point and then to deposit them simultaneously in a corresponding line in the receptacle at the deposit point; for this purpose one may for example provide a corresponding plurality of aligned, juxtaposed and simultaneously operable packet handling devices, or a single packet-handling device provided with a corresponding plurality of aligned, juxtaposed and simultaneously operable pick-up members.

Where the packets are to be deposited in a plurality of parallel rows, a variety of arrangements is possible. For example, the packets or pouches may be fed to the pick-up point in a plurality of rows, and, in a manner similar to that mentioned above for multiple pick-up from a single row, a plurality of simultaneously operable packet handling devices and/or suction pick-up members may be positioned for simultaneous pick-up and subsequent simultaneous de-position of one or more adjacent packets from each of a plurality of rows.The preferred arrangement, however, is for the packets to be fed to the pick-up point in single file, with the or each packet handling device being moveable according to a predetermined programme for deposition of a packet in its required row; for example to or each packet handling device may be radially spaced from and connected to a central drive shaft by a radially extendible linkage (for instance a further piston and cylinder) operable according to the predetermined programme to adjust the radial distance between device and shaft to position the device correctly for pick-up from the single row at the pick-up point and deposition in the predetermined required row at the deposition point.In would be possible for such- a radially extendible and retractable linkage to carry a plurality of simultaneously operable packet handling devices or one or more such devices provided with a plurality of simultaneously operable suction pick-up members, for simultaneous pick-up and subsequent simultaneous deposition of two or more adjacent packets in a single row and/or a plurality of rows, but for accuracy and reliability of operation it is preferred to supply the packets or pouches to the pick-up point in single file and to deposit them at the deposition point in one row at a time.

In all instances, the intermittent movement of the receptacle through the deposit point is programmed to provide for the required deposition pattern, and as indicated above this may involve movement of the receptacle to and fro through the deposition point where two or more layers are to be deposited, one layer normally being completed before the next is commenced.

Whilst apparatus according to the invention may be provided with a single packet handling device according to the invention, the apparatus preferably has a plurality of such devices spaced around a circuit for movement between the pickup and deposition points on the circuit. It is in fact preferred to provide as many packet handling devices as possible, compatible with the size of packet or pouch to be handled and with the deposition pattern that is required. Preferably, the packet handling devices, or at least some of them, will be detachable from the apparatus so that it can be modified according to the packets or pouches to be handled and according to the required packing programme.

The invention is illustrated, by way of example only, by the following description of a preferred embodiment, to be taken in conjunction with the accompanying drawings, in which: Fig. 1 is a schematic elevation view, partly in section, of a packet handling device according to the invention, and Fig. 2 is a schematic plan view illustrating the operation of an apparatus according to the invention provided with devices as shown in Fig. 1.

The packet handling device 2 illustrated in Fig.

1 comprises a cylinder 4 and piston 6 from which a suction pick-up member 8 depends via a lost motion connection 11. The suction pick-up member 8 has a plate or frame structure 10 carrying a downwardly projecting flared suction nozzle 12 connected to a flexible suction line 14.

Also secured to plate or frame structure 10 is a wall 1 6 of resiliently deformable and compressible foamed plastics material, this wall being generally elliptical in plan view and surrounding the nozzle 12. The lost motion connection 11 comprises a plate 1 8 attached rigidly to the lower end of moving piston 6 and a plurality of rods 20 which are fixed at their lower ends to the pick-up member 8 and whose upper ends pass freely through apertures in plate 18, stops 22 on the upper ends of rods 20 preventing these upper ends from passing through plate 1 8. The device 2 is shown with pick-up member 8 in operative engagement with a packet 24, the wall 1 6 being deformed and compressed under the weight of member 8 and rods 20 so that with suction applied nozzle 12, which projects downwardly less than wall 16, is in contact with the upper surface of packet 24. Fig. 1 shows device 2 with the piston 6 extended downwardly for pick-up or deposition of the packet 24. On continued downward movement of piston 6, the plate 18 slides down rods 20 so that no undue pressure is placed upon packet 24, which'is subjected solely to the weight of pick-up member 8 and rods 20.

To limit the extent of such lost motion in the downward and subsequent return strokes of piston 6, switch members 26 are located on plate 1 8 and rod 20 so that they contact shortly after plate 18 begins to slide down rods 20, such contact operating a switch (not shown) to stop the downward movement of piston 6 and immediately shortly thereafter initiate its return upward stroke to take up the small amount of lost motion and raise the pick-up member 8. The said switch may also control the suction applied through nozzle 12.For example, in one arrangement a closeable passageway or tube (not shown) is open to the atmosphere at one end and communicates at the other end with nozzle 12 and/or line 14 at or adjacent to their junction; suction applied continuously via line 14 is transmitted through nozzle 12 when the said passageway or tube is closed and is effectively nullified when it is opened, and the opening and closing of the said passageway or tube is controlled by the said switch.

The packet handling device 2 according to the invention shown in Fig. 1 may thus operate as follows. With a packet 24 positioned on a support at a predetermined pick-up point, the device 2 is positioned with its suction pick-up member 8 suspended centrally and vertically above the packet. The packet 24 may for example be a grocery packet, for example a sealed package, pouch or sachet of rice.For the pick-up operation piston 6 is extended vertically downwards until pick-up member 8 comes to rest on packet 24 and remains there under its own weight and that of rods 20 as piston 6 continues to descend a short distance until contact is made between contacts 26 to operate the switch (not shown) which halts the downward stroke of piston 6, closes the above mentioned air passageway or tube (not shown) communicating with line 14 or nozzle 12 so that suction is applied through nozzle 12, and initiates the upward stroke of piston 6 to its retracted position. The resiliently compressible wall 1 6 deforms as illustrated under the weight applied to conform to the packet surface and to help smooth out this surface, so that this surface and nozzle 1 2 are in contact when or before suction is applied through the nozzle.The packet is thus positively but gently and safely engaged and is raised by the pick-up member 8 on the upward stroke of piston 6. The device 2 is then moved to the predetermined deposit point whereupon piston 6 is extended vertically downwards again until packet 24 carried by pick-up member 8 is positioned on the base.of a receptacle (or on a previously deposited packet therein) under the weight of the pick-up member 8 and rods 20.

Piston 6 continues to move downwardly a short distance until contact between contacts 26 again operates the said switch (not shown) which operates to terminate this downward stroke, open the said air passageway or tube (not shown) communicating with line 14 or nozzle 12 to nullify the suction, and initiates the upward stroke of piston 6 to its retracted position. The packet 24 is thus placed positively but gently and safely at the deposition point and is then released from pick-up member 8 by the nullification of the suction, and the device 2 with the pick-up member 8 in its raised position is moved to the said or another pick-up position for another pick-up operation.

As shown in Fig. 1, the packet handling device 2 is conveniently mounted on a central rotary drive shaft 28 by a horizontal radial arm 30 which preferably incorporates a further cylinder 32 and piston 34 by way of which the arm can be controlledly extended and retracted to vary the radial spacing of device 2 from central drive shaft 28. Piston and cylinder units 4, 6 and 32, 34 are each conveniently operated pneumatically by conventional means not shown.

Packing apparatus according to the invention may have a single device 2 mounted on arm 30 from drive shaft 28 which is operable (by means not shown) to rotate device 2 repeatedly between a pick-up point where it picks up a packet to a deposit point where it deposits the packet in a required position, e.g. in a receptacle. Preferably, however, the apparatus will have a plurality of devices 2 spaced uniformly around shaft 28 on respective arms 30, such an apparatus 36 having four devices 2 being illustrated schematically in plan view in Fig. 2. In Fig. 2 the apparatus 36 is used in conjunction with a feed conveyor 38 and a receptacle conveyor 40. In Figs. 1 and 2, like reference numerals indicate like parts.

In operation of the Fig. 2 apparatus packets 24 to be transferred are fed at right angles onto feed conveyor 38, a smooth band conveyor which conveys them towards a stop plate 42 which brings them to rest with the conveyor slipping beneath them. The region immediately adjacent the upstream face of the stop plate is the pick-up point or region, and the packets 24 move incrementally in single file to this point or region as the preceding packet or packets are removed, the conveyor 38 operating continuously. Parallel to and laterally spaced from conveyor 38 is conveyor 48 carrying receptacles 44 to be filled with the packets 24 from conveyor 38.Between the two conveyors is the apparatus 36 according to the invention, this being disposed so that on rotation of the arms 30 in a clockwise direction each device 2 comes sequentially over the said pick-up point or region, then over the receptacle to be filled, and then over the pick-up point or region again.

The Fig. 2 apparatus is shown set up for transferring the packets 24 from the single file on feed conveyor 38 and depositing them in four parallel rows in the receptacle 44 on conveyor 40.

The lowermost arm 30 as seen in Fig. 2 has its piston 34 in the fully retracted position and its associated device 2 positioned centrally and vertically above a packet 24 at the pick-up position on conveyor 38; at the same time, the uppermost arm 30 as seen in Fig. 2 has its piston 34 partially extended with the associated device 2 carrying a packet 24 located vertically and centrally over the deposition point for depositing the carried packet 24 in the third row of packets in receptacle 44 on conveyor 40. The left-hand arm 30 as seen in Fig. 2 has its piston 34 in its fully extended position with its device 2 carrying a packet 24 for subsequent deposition in the fourth row of packets in receptacle 44. The right-hand arm 30 as seen in Fig. 2, which has previously deposited a packet in the second row in receptacle 44, has its piston 34 in a partially extended position.With the apparatus 36 stationary in the position shown in Fig. 2, device 2 on the lowermost arm 30 is operated to pick up its packet whilst device 2 of the uppermost arm 30 is operated to deposit its packet, each in the manner described above with reference to Fig. 1.

Substantially simultaneously, the piston 34 of the left-hand arm 30 is extended from the fully retracted position (which it would have adopted for pick-up from conveyor 38) to its illustrated fully extended position ready for the next deposition step, and the partially extended piston 34 of the right-hand arm 30 is withdrawn to its fully retracted position ready for the next pick-up from conveyor 38. With these operations complete and all pick-up members in the raised position, the apparatus 36 is rotated clockwise through 900 by shaft 28 and the packet pick-up and deposit are repeated.Each arm when in the intermediate position between deposit and pickup point has its piston 34 fully retracted (if necessary) so that its device 2 is properly positioned for the next pick-up step, and each arm 30 when in the intermediate position between pick-up and deposit points has its piston 34 extended (if necessary) the appropriate amount ready for deposition of its packet in the predetermined row in receptacle 44.With four arms 30 depositing the packets 24 in four rows as illustrated, a given arm always deposits in the same row, and so goes through the same operational sequence in each cycle; thus the lowermost arm 30 as seen in Fig. 2 retains its piston 34 fully retracted through-out each cycle, whereas the left-hand arm as seen in Fig. 2 is always fully extended when in the indicated position and then fully retracted when it comes to the right-hand intermediate position; and the other two arms always have their pistons 34 extended to their respective partially extended positions when they come to the left-hand intermediate position and fully retracted when they come to the right-hand intermediate position.

Programming of the controls for operation of each arm is thus simple. More complex programming would be necessary where there is no direct correlation between number of arms and number of rows to be deposited so that a given arm deposits in different rows in consecutive cycles, but this of course is possible. For efficiency of operation it is preferred to employ as many arms 30 and devices 2 as possible; for example an apparatus similar to that of Fig. 2 might have eight, twelve or sixteen arms 30 and devices 2. At least some of the arms 30 and/or devices 2 provided with any given apparatus are preferably detachable so that the apparatus can readily be modified according to the size of packet to be handled and according to the deposition pattern required.Each piston and cylinder 32, 34 is preferably settable to provide for extension and retraction of piston 34 in predetermined fixed increments, with the number and size of these increments being adjustable according to the particular packing programme to be performed.

Operation of the conveyor 40 is programmed to synchronise with operation of apparatus 36, so that the conveyor 40 is advanced one packet length after the completion of each lateral row; where two or more layers of packets are to be packed into the receptacle, the conveyor 40 will be programmed to reciprocate the receptacle 44 incrementally through the deposit point in the manner previously explained.

It will be appreciated that the above described operation of the Fig. 2 apparatus is purely exemplary; the apparatus may thus be programmed to deposit the packets in any required sequence different from that mentioned above. Although currently less preferred, the packets 24 can be fed to form a plurality of rows on conveyor 38 instead of being fed in single file, with the arms 30 being programmed to pick up from as well as to deposit in a predetermined row; indeed, with this arrangement, each arm 30 may remain of respective fixed length throughout each cycle, one arm always picking up from and depositioning in a first row and the next always picking up from and depositing in a second row, and so on; once again, however, the length of each arm is preferably adjustable so that the same apparatus can be modified to cope with packets of various size and with various pick-up and deposition patterns. Moreover, although again currently less preferred, each device 2 and/or pick up member as shown in Fig. 2 may be replaced by a simultaneously operable set arranged to 'simultaneously pick up and then simultaneously deposit a plurality of packets from at least one row. Devices other than the switch-operating contacts 26 may be used to control the movement of piston 6 and/or the application and release of suction through nozzle 12. Lost motion connections other than the simple rod and sliding plate arrangement illustrated are possible, and two or more nozzles 12 may be provided for each pick-up member. Whilst pistons and cylinders are preferred for raising and lowering the pick-up members and for extending and retracting the arms 30, either or both may be replaced by another type of extendible and retractable carrier or supporting linkage. The illustrated stop plate 42 over conveyor 38 is adjustable longitudinally of the conveyor for accurate location of packets 24 at the pick-up position, according to their size and orientation.

The packet handling device and apparatus according to the invention are particularly suited for the handling of "soft" packets, e.g. packaged grocery products.

Claims (2)

1. A packet handling device operable to pick up and place a packet, the device comprising a suction pick-up member depending via a longitudinal lost motion connection from a vertically extendible and retractable carrier member.

2. A device according to claim 1 including means to control the application and release of suction by the suction pick-up member.

2. A device according to claim 1 wherein the carrier member comprises a piston and cylinder

3. A device according to claim 1 or 2 wherein the suction pick-up member comprises a plate or frame carrying at least one downwardly directed suction nozzle attached to a suction line and surrounded by a resiliently deformable wall extending downwardly beyond the suction nozzle or nozzles for resilient contact with a packet during operation.

4. A device according to any of claims 1 to 3 including at least one switch means operable by the downward stroke of the extendible and retractable carrier to restrict the extend of the lost motion and/or to control the application and release of suction by the suction pick-up member.

5. Packing apparatus comprising at least one packet handling device according to any of claims 1 to 4 mounted for repeated movement between pick-up and deposit points, and means for intermittently effecting the said movement and operating the or each suction pick-up member and extendible and retractable carrier according to a predetermined programme for the sequential pickup of a packet from a pick-up point and its transport to and deposit at a deposit point.

6. Apparatus according to claim 5 wherein the or each device is radially spaced from and connected to a central drive shaft for rotation by and in a circuit about the drive shaft between pickup and deposit points.

7. Apparatus according to claim 6 wherein the or each device is connected to the drive shaft by an arm extendible and retractable radially of the drive shaft.

8. Apparatus according to claim 7 wherein the or each arm is extendible and retractable by increments adjustable in number and extent.

9. Apparatus according to claim 7 or 8 wherein the or each arm comprises a further piston and cylinder.

10. A packet handling device substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawings.

11. Packing apparatus substantially as hereinbefore described with reference to Fig. 2 of the accompanying drawings.

New claims or amendments to claims filed on 3 June 81 Superseded claims: 1 New or amended claims:

1. A packet handling device operable to pick up and place a packet, the device comprising a suction pick-up member depending via a longitudinal lost motion connection from a vertically extendible and retractable carrier member, and means operable by the stroke of the carrier member to restrict the extent of the lost motion.