GB1584191A

GB1584191A - Apparatus for passing the closed end of a bag through a tape applying device

Info

Publication number: GB1584191A
Application number: GB2553077A
Authority: GB
Original assignee: METROMETHODS Ltd
Current assignee: METROMETHODS Ltd
Priority date: 1978-05-19
Filing date: 1978-05-19
Publication date: 1981-02-11

Description

(54) IMPROVEMENTS IN OR RELATING TO APPARATUS FOR PASSING THE CLOSED END OF A BAG THROUGH A TAPE APPLYING DEVICE (71) We, METROMETHODS LTD, a British Company, of Shortmead Street, Biggleswade, Bedfordshire SG18 OBB do hereby declare the invention for which we pray that a patent may be granted to us and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to apparatus for passing the closed end of a bag through a tape applying device.

According to the present invention there is provided apparatus for passing the closed end of a bag through a device for automatically applying a loop of adhesive tape to a closed end of a bag passed through the device to secure the end portion closed, the apparatus comprising a station for receiving a tape applying device a guide for guiding, in use, an end portion of the bag to the tape applying device, a pair of co-operating jaw members for embracing a closed end portion of the bag and for moving the end portion through the tape applying device, in use, means acting on each of the members for positively biassing the jaw members together to grip the portion of the bag as the end portion is moved, in use, through the tape applying device and means for opening the jaw members, against the action of the biassing means, prior to and then subsequent to the movement, in use, of the end portion through the tape applying device to receive and release the end portion of the bag.

One of the jaw members may be mounted for rotation about an axis with respect to the other of the jaw members. In this case the means for opening may comprise means for rotating the one jaw member with respect to the other jaw member against the action of the bias means.

In this case the means for opening may comprise separate means for rotating the one jaw member prior to and subsequent to the movement of the end portion of the bag through the tape applying device.

The or each means for rotating may comprise means for moving the one jaw member and detent means disposed to engage the one jaw member to, together with the means for moving, cause the one jaw member to rotate with respect to the other jaw member.

Preferably the one jaw member is pivotably mounted on the other jaw member.

In this case the means for moving the one jaw member may comprise means for moving the other jaw member, and the other jaw member.

The other jaw member may be pivotably mounted about an axis of rotation disposed such that the first mentioned axis of rotation of the one jaw member lies intermediate the axis of rotation of the other jaw member and the tape applying device.

Preferably the one jaw member has its jaw facing against the direction of movement, in use, of the end portion of the bag through the apparatus. In this case the apparatus may comprise means for holding the one jaw member, in a position, to oppose the movement, in use, of the end portion of the bag until the bag is gripped between the pair of jaw members and thence to release the one jaw from said one position.

The means for holding may be constituted by the detent means of the means for rotating the one jaw member prior to movement of the end portion of the bag through the tape applying device.

The means for moving the other jaw member may be actuated by a switch responsive to movement of the end portion of the bag into the guide.

Preferably means are provided for introducing a delay between the switching of the switch by the movement of the bag and the movement of the other jaw member.

The means for moving the other jaw member may comprise a reciprocable ram.

In any of the above cases the apparatus may further comprise a further jaw member mounted in the same sense as and for movement with the other jaw member, the other and further jaw members being mounted on respective sides of the guide.

The apparatus may further comprise means for feeding the end portion of the bag along the guide prior to gripping of the bag by the pair of jaw members.

The means for feeding may include means for holding the end portion of the bag on either side of the guide.

Specific embodiments of the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a side view of an apparatus for passing the closed ends of plastics bags through a tape applying device mounted in the apparatus; Figure 2 is an enlarged view of the jaw members showing the operation of the jaw members of the apparatus of Figure 1; Figure 3 is an inverted sectional view of the jaw members of the apparatus of Figure 1 in their closed portion; Figure 4 is a side view of the infeed apparatus of Figure 1; Figure 5 is a view from above of an alternative embodiment of the jaw members; and Figure 6 is a sectional view of Figure 5 along the line A-A.

Figure 1 shows an apparatus 10 for passing the closed ends of plastics bags through a tape applying device 14 which apparatus comprises a chassis 11 formed by two spaced parallel plates 12 (see Figure 3) and each of which has a slot 13 extending from one side into its respective plate 12 to an enlarged closed end 1 3a to together define a guide for the end portion of a bag, the tape applying device 14 being disposed between the plates 12 with its tape applying mechanism, generally indicated at 15, lying in the central region of the guide formed by the slots 13, a bag infeed mechanism, generally indicated at 16, mounted on chassis 11, intermediate the entrance of the slots 13 and the tape applying mechanism 15, for feeding the end portions of bags toward the tape applying mechanism 15, and a mechanism generally indicated at 17 for gripping the end portion of each bag, moving it through the tape applying mechanism 15 and subsequently releasing the taped end portion adjacent the closed end 13a for subsequent removal thereform.

Referring to Figures 1 to 3 mechanism 17 includes three elongate jaw members 18, 19 and 20, each of which has a jaw formed at one end. Jaws of jaw members 18 and 20 are indicated at 18a and 20a, whilst that of jaw member 19 is not shown. It should be noted that in Figures 1 and 2 jaw members 18 and 20 are shown in a first solid line position and three other chain line positions.

Referring to Figure 3,jaw members 18, 19 and 20 are mounted between plates 12.

Jaw members 18 and 19 are mounted at their other ends on a shaft 21, which extends through the plates 12 and is mounted at its end on the plates 12 by respective bearings 22, with their jaws facing in the direction of movement of the end portion of a bag through the apparatus (see arrow A in Figure 1). Jaw members 18 and 19 are fixed together by screws 23 and 24 and bolt 25 and spaced apart, by spacers 26 to 28, to lie adjacent the inner faces of respective plate 12.

Spacer 27 is formed with a central bore 29 in which a bush 29a is located. A pivot 30 extends through bush 29a and jaw member 20, to pivotably mount jaw member 20, adjacent its other end, on jaw member 18 such that the jaw member 20 lies between jaw member 18 and its adjacent plate 12 with its jaw 20a facing against the direction of the arrow A. A part circular slot 31 is formed in each of the plates 12 to provide clearance for rotational movement of pivot 30 about shaft 21.

As will be seen from Figures 1 and 2 jaws members 18 and 20 are positively biassed together by a spring 32, which is mounted at its ends on spring posts 34 and 35 respectively. Spring post 34 also carries a stop 36 for engaging jaw member 20 to limit the extent that jaws 1 8a and 20a can be closed.

A reciprocating ram 37 is pivotably mounted at one end to the chassis 11 by spaced parallel plates, one of which is indicated at, 38 and shaft 39 such that its other end 40 extends between the plates 12 to engage around the bolt 25, which connects between jaw member 18 and 19. Axial movement of the ram 37 thus causes pivotable movement of the assembly of jaws 18, 19 and 20 about shaft 21. It will be noted that ram 37 is shown in both broken and solid line positions the latter of which corresponds with the solid line position of jaw members 18 and 20. The ram 37 is reciprocable between its solid and dotted line positions, as shown in Figure 1, by means of a solenoid valve 37a via lines 37b and 37c. A transversely extending plate 40a is mounted on the movable portion of the ram 37 such that it engages a micro switch 65 when the ram 37 is in its dotted line position.

The other end of jaw member 20 is formed with a fin 41, which extends at right angles to the axis of jaw member 20 in the direction in which jaw 20a faces and which forms an abutment face 42, which faces towards the other end of the jaw member 20.

The other side of the other end of jaw member 20 is cut away to form a concave abutment face 43.

A stop 44 is mounted on that plate 12, which is adjacent the jaw member 19, and extends in the gap between plates 12 to engage abutment face 42. The stop 44 is disposed such that when jaw member 18 is moved into its solid line position, stop 44 holds jaw member 20 against the action of spring 32 in a position in which jaw member 20 will resist the movement of the end portion of a bag down the slots 13 to the tape applying mechanism 15.

A stop 45 is mounted on that plate 12, which is adjacent the jaw member 20, and extends into the gap between plates 12 to engage abutment face 43. The stop 45 is disposed adjacent shaft 21 at a level intermediate the tape applying mechanism 15 and the closed end 13a and at a position intermediate the shaft 21 and the slots 13.

The infeed mechanism 16 generally comprises a pair of gear wheels 46 and 47 rotatably mounted on the outside of the plate 12 shown in Figure 1 on either side of the slot 13 in that plate, such that they intermesh at a point adjacent the slot 13, a wheel 48 (see Figure 4), having a peripheral groove 49, in which an O-ring 50 is mounted, is mounted outside the other plate 12 for rotation with gear wheel 47, a further wheel 51 having a peripheral groove 52 is rotatably mounted on the other plate 12 such that its peripheral groove 52 engages the O-ring 50 opposite the nip formed by gear wheels 46 and 47, and a motor 53, mounted on the chassis 11 for driving gear wheel 46, via an intermediate gear wheel 54, and hence for driving gear wheel 47 and grooved wheel 48.

The gear wheel 47 and wheel 48 are mounted on a common shaft 55, which is held for rotation in a spring load bearing 56.

Each end of the spring load bearing 56 extends through a respective one of eccentricly disposed circular apertures 57 each of which is formed in a respective plate 12 to allow lateral movement of the bearing 56 away from channels 13 against biassing spring 58.

A switch actuator 59 is mounted between plates 12. The switch actuator 59 is biassed into a non-operative position in which it extends between channels 13 adjacent the point of intermeshing of gear wheels 46 and 47.

The tape applying device 14 is know per se and is of the type described in our United Kingdom Patent No. 1334146 wherein the device as a whole is reference 25. Reference should be made to United Kingdom Patent No. 1334146 for a full description of the construction and mode of operation of the device, but in essence when an end portion of a bag is pressed into one of the recesses of the tooth wheel 60 of the tape applying mechanism 15 adhesive tape is drawn from a spool tap rotatably mounted on shaft 61 (see Figure 1), part way round the end portion, and as the end portion continues to move along slots 13, in the direction of arrow A, the wheel 60 is rotated anti-clockwise causing tape to be around the end portion.

The portion of tape encircling the end portion of the bag is then severed by a pivotably mounted knife 62 in response to the end portion of the bag deflecting arm 63 of the mounting 64 of the knife 62.

At the start of each operation the ram 37 is in its solid line position and hence jaw members 18 and 20 are in their solid line positions and jaw member 19 is in a position parallel to jaw 18 on the other side of the gap between plates 12.

In operation the open end of a bag is fed in elongated form into the guide formed by slots by hand. Alternatively it may be fed in by pair of conveyor belts. The outer ends of the slots 13 are widened into V-information to facilitate insertion of the end portion of the bag into the slot. One end of the end portion of the bag is gripped by gear wheels 46 and 47 on one side of the apparatus and wheels 48 and 51 on the other side of the apparatus 10, so that the end portion of the bag is stretched across the gap between the plates 12, and fed into jaw 20a of jaw member 20.

In the course of its passage along slots 13, the end portion of the bag deflects the switch actuator 59 to its chain line position and maintains it in this position until all of the end portion of the bag has been fed through the infeed mechanism 16, at which point the switch actuator 59 returns to its solid line position. Control circuitry (not shown) detects the making and subsequent braking of the switch controlled by switch actuator 59, and in response to the breaking of the switch solenoid valve 87a is actuated to retract the hydraulic ram 37 towards its broken line position.

Retraction of the hydraulic ram 37 causes jaw members 18 and 19 to rotate towards the closed end 13a of guides 13 engaging the trailing edge of the end portion of the bag causing it to bunch in the jaw 20a. During this section of movement jaw member 20 is essentially maintained in its solid line position because the spring 32 urges abutment face 42 against the stop 44. However the pivotable movement of jaw member 18 rotates the position of pivot 25 and hence causes the abutment face 42 to slide along stop 44. By the time chain line position B (seen most clearly in Figure 2) is reached the end portion of the bag has been compressed into a narrow neck, which is gripped between jaws 18 and 20a and abutment face 42 is virtually clear of stop 44.

In position B the stop 36 engages jaw membe 36, and the continued pivotable movement of the jaw members 18 and 19 is imparted to jaw member 20, such that all three jaw members rotate about shaft 21, pushing the neck of the bag through the tape applying mechanism 15, which tapes the neck and then severes the tape as described above. The provision ofthe jaw member 19 ensures that the bunched portion of the bag, which passes through the tape applying mechanism 15, extends at right angles to the direction of movement of that portion.

This configuration is desirable when the apparatus is used with the tape applying mechanism described.

When position C is reached abutment face 43 engages stop 45 which together with the continued pivotable movement ofjaw members 18 and 19 causes jaw 20 to rotate about the axis of pivot 25. As the distance between jaw 20a and pivot 25 is shorter than the distance between jaw 18a and shaft 21, jaw 20a accelerates away from jaw 18a, opening the jaw members 18 and 20 and releasing the end portion of the bag (see position D).

When position D is reached the plate 40a engages switch 65. The operation of the switch 65, after a delay to allow the removal of the bag from the closed end 13a reverses the solenoid valve 37a causing the ram 37 to return towards its solid line position, causing jaw members 18, 19 and 20 to pass through position C. Just before position B is reached the abutment face 42 engages stop 44, which stops any further significant movement of jaw member 20.

The continued return movement of ram 37 opens jaw members 18 and 20 against the action of spring 32 until ram 37 and hence jaw member 18 reaches its solid line position, in which position the apparatus 10 is reset to await its next cycle of operation.

Figures 5 and 6 show an alternative form of the jaw members 18 and 20. In this embodiment a plate 66, having a chamfered leading edge 67, is mounted on the upper surface of the jaw member 18 to extend over its jaw 18a. The trailing edge of the jaw 20a is also chamfered to cooperate with the leading edge 67 of the plate 66 such that the end of the bag 69 is trapped between the chamfered edges 67 and 68 when position B is reached in the first half of the cycle of operation of the apparatus 10.

The resultant distortion of the bag 69 enables the bag 69 to be gripped more firmly without damage to the bag 69 occurring.

WHAT WE CLAIM IS: 1. Apparatus for passing the closed end of a bag through a device for automatically applying a loop of adhesive tape to a closed end of a bag passed through the device to secure the end portion closed, the apparatus comprising a station for receiving a tape applying device a guide for guiding, in use, an end portion of the bag to the tape applying device, a pair of co-operating jaw members for embracing a closed end portion of the bag and for moving the end portion through the tape applying device, in use, means acting on each of the members for positively biassing the jaw members together to grip the portion of the bag as the end portion is moved, in use, through the tape applying device and means for opening the jaw members, against the action of the biassing means, prior to and then subsequent to the movement, in use, of the end portion through the tripe applying device to receive and release the end portion of the bag.

2. Apparatus as claimed in claim 1 wherein one of the jaw members is mounted for rotation, about an axis, with respect to the other of the jaw members and wherein the means for opening comprise separated means for rotating the one jaw member prior to and subsequent to the movement of the end portion of the bag through the tape applying device.

3. Apparatus as claimed in claim 2 wherein one or each means for rotating comprise means for moving the one jaw member and detent means disposed to engage the one jaw member, together with the means for moving, cause the one jaw member to rotate with respect to the other jaw member.

4. Apparatus as claimed in claim 2 or claim 3 wherein the one jaw member is pivotably mounted on the other jaw member.

5. Apparatus as claimed in claim 4 wherein the means for moving the one jaw comprise means for moving the other jaw member, and the other jaw member.

6. Apparatus as claimed in claim 5 wherein the means for moving the other jaw member comprises a reciprocable ram.

7. Apparatus as claimed in claim 5 or claim 6 wherein the means for moving the other jaw member is activated by a switch responsive to the movement of the end portion of the bag into the guide.

8. Apparatus as claimed in claim 7 further comprising means for introducing a delay between the switching of the switch by the movement of the bag and the movement of the other jaw member.

9. Apparatus as claimed in any one of claims 2 to 8 wherein the other jaw member is pivotably mounted about an axis of rotation disposed such that the first mentioned axis of rotation of the one jaw member lies intermediate the axis of rotation of the other jaw member and the tape applying device.

10. Apparatus as claimed in any one of claims 2 to 9 wherein the one jaw member has its jaw facing against the direction of movement, in use, of the end portion of the bag through the apparatus.

11. Apparatus as claimed in claim 10 further comprising means for holding the one jaw member, in a position, to oppose the movement, in use, of the end portion of the bag until the bag is gripped between the pair ofjaw members and thence to release the one jaw from said one position.

12. Apparatus as claimed in claim 11 wherein the means for holding are constituted by the detent means of the means for rotating the one jaw member prior to movement of the end portion of the bag through the tape applying device.

13. Apparatus as claimed in any one of the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. apparatus is used with the tape applying mechanism described. When position C is reached abutment face 43 engages stop 45 which together with the continued pivotable movement ofjaw members 18 and 19 causes jaw 20 to rotate about the axis of pivot 25. As the distance between jaw 20a and pivot 25 is shorter than the distance between jaw 18a and shaft 21, jaw 20a accelerates away from jaw 18a, opening the jaw members 18 and 20 and releasing the end portion of the bag (see position D). When position D is reached the plate 40a engages switch 65. The operation of the switch 65, after a delay to allow the removal of the bag from the closed end 13a reverses the solenoid valve 37a causing the ram 37 to return towards its solid line position, causing jaw members 18, 19 and 20 to pass through position C. Just before position B is reached the abutment face 42 engages stop 44, which stops any further significant movement of jaw member 20. The continued return movement of ram 37 opens jaw members 18 and 20 against the action of spring 32 until ram 37 and hence jaw member 18 reaches its solid line position, in which position the apparatus 10 is reset to await its next cycle of operation. Figures 5 and 6 show an alternative form of the jaw members 18 and 20. In this embodiment a plate 66, having a chamfered leading edge 67, is mounted on the upper surface of the jaw member 18 to extend over its jaw 18a. The trailing edge of the jaw 20a is also chamfered to cooperate with the leading edge 67 of the plate 66 such that the end of the bag 69 is trapped between the chamfered edges 67 and 68 when position B is reached in the first half of the cycle of operation of the apparatus 10. The resultant distortion of the bag 69 enables the bag 69 to be gripped more firmly without damage to the bag 69 occurring. WHAT WE CLAIM IS:

1. Apparatus for passing the closed end of a bag through a device for automatically applying a loop of adhesive tape to a closed end of a bag passed through the device to secure the end portion closed, the apparatus comprising a station for receiving a tape applying device a guide for guiding, in use, an end portion of the bag to the tape applying device, a pair of co-operating jaw members for embracing a closed end portion of the bag and for moving the end portion through the tape applying device, in use, means acting on each of the members for positively biassing the jaw members together to grip the portion of the bag as the end portion is moved, in use, through the tape applying device and means for opening the jaw members, against the action of the biassing means, prior to and then subsequent to the movement, in use, of the end portion through the tripe applying device to receive and release the end portion of the bag.

13. Apparatus as claimed in any one of the

preceding claims wherein the apparatus further comprises a further jaw member mounted in the same sense as and for movement with the other jaw member, the other and further jaw members being mounted on respective sides of the guide.

14. Apparatus as claimed in any one of the preceding claims further comprising means for feeding the end portion of the bag along the guide prior to gripping of the bag by the pair ofjaw members.

15. Apparatus as claimed in claim 14 wherein the means for feeding includes means for holding the end portion of the bag along the guide prior to gripping of the bag by the pair of jaw members.

16. Apparatus for passing the closed end of a bag through a device for automatically applying a loop of adhesive tape to a closed end of a bag passed through the device to secure the end portion closed, the apparatus being substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 4 of the accompanying drawings or Figures 1 to 4 as modified by Figures 5 to 6 of the accompanying drawings.