GB2117739A - Grasping device for pieces of textile material or the like piled up to form a pack - Google Patents

Abstract

Grasping device for pieces of textile material or the like piled up to form a pack 14 comprising a rocking bracket 6 carrying a roller 8 covered with a material having a strong friction coefficient, such as rubber, and integral to a toothed wheel 10 meshing with a pawl 11 hinged on said bracket and actuated by a spring 12 so that, when the roller is moved on the pack of pieces towards the vertical passing across the oscillation fulcrum 7 of said bracket, said roller is prevented from rotating by means of the ratchet coupling while, when it is moved to the opposite direction, the roller can rotate about its own axis, said device being characterized in that said fulcrum is supported by a spindle 1 arranged to move up and down within a block 3 resting on the pack of pieces, so that when the roller moves towards the block which is still resting on the pack it causes the top piece 13 to form a fold which is trapped against the block itself, which allows the piece to be picked up when the whole device is raised. Textile pieces may be picked up and transported to an assembly device such as a sewing machine. <IMAGE>

Description

SPECIFICATION Grasping device for pieces of textile material or the like piled up to form a pack.

The present invention relates to a grasping device suitable to pick up, one by one, pieces of textile material or the like from a pack of pieces, said device being arranged to be applied to a picking up and transporting machine, said machine bringing each piece near an operator which can therefore easily grasp it in order to carry out the following operations, such as for example the assembling of pieces by means of a sewing-machine.

It is rather difficult to pick up one single piece of material by hand from a pile or pack obtained in a particular size by means of suitable shears which cut said pack consisting of 20 to 50 pieces together prior to the sewing operation.

Different either pneumatic or mechanical and electro-mechanical devices have been accomplished in order to speed up said grasping operation.

Pneumatic devices are based on the formation of a vacuum on the piece to be picked up; however they are expensive and cannot be used in all kinds of factories as for instance in small factories compressed air systems are not available.

Mechanical devices have also been accomplished as for example the one disclosed in U.S. Patent No. 2,042,734 in which two rollers, which can move across the pack of pieces but are prevented from rotating are provided, so that they form a fold on the top piece which is therefore isolated from the one placed immediately below and is then moved away from the device by means of a movement parallel to the axis of the two rollers, said rollers being adapted to rotate during their backward movement only, i.e. the revers movement with respect to the one which has caused the separation of the top piece from the pack below.

The above described patent of the prior art has not however solved the problem of grasping pieces in a sure and simple manner, this problem being on the contrary solved by the grasping device of the present invention which comprises a rocking bracket carrying a roller covered with a material having a strong friction coefficient, such as rubber, and coupled with a ratchet means carried by said bracket so that when the roller is moved on the pack of pieces towards the vertical passing across the oscillation fulcrum of said bracket, said roller is prevented from rotating by means of the ratchet coupling, while, when it is moved to the opposite direction, the roller can rotate about its own axis, said device being characterized in that said fulcrum is supported by a spindle arranged to move up and down within a block resting on the pack of pieces, so that when the roller moves towards the block which is still resting on the pack it causes the top piece to form a fold which is trapped between the roller itself and the block and which allows the piece to be picked up when the whole device is raised.

Further features of the present invention consist in that: -the block is provided with a projection against which the piece is trapped by the roller; -at its lower portion the spindle is provided with a collar which rests on the pack of pieces when the roller is at its outermost position, while it is substantially against the upper portion of the block for the raising thereof when roller is against the block itself, the piece being trapped therebetween; -the rocking bracket is provided with two side ears which enclose the block so that when the roller is draged across the pack of pieces, it is guided with respect to the block against the block projection;; -a switch is provided which closes an electric circuit when the roller is at its outermost position, so that in this position the electric circuit is closed on a means which causes said spindle to rise automatically and therefore the roller to move across the pack against the block, the piece being trapped therebetween.

These features and the advantages of the device of the invention will now be described in accordance with a particular embodiment given hereinafter by way of example only, with reference to the accompanying drawings, in which: Figure 1 is an elevation view of the device, the roller being at its outermost position; Figure 2 is a plan view of the device as shown in Fig. 1; Figure 3 is an elevation view of the device, the piece being trapped ready to be raised.

As shown in the drawings, the upper portion of a spindle 1 is provided with a hole 2 through which a cross bar carried by a picking up machine not shown in the figures is engaged, and is passing through a block 3 which is caused to rest on the pack of pieces to be grasped. At its lower portion spindle 1 is provided with collar 4 which slides up and down in hole 5 drilled in block 3 at the raising and lowering of spindle 1.

Spindle 1 also carries a bracket 6 which is hinged at fulcrum 7 and which in turn carries a roller 8 covered with rough material, such as rubber; roller 8 rotates about pin 9 and is integral to a toothed wheel 10 mashing with a pawl 11 (together forming a ratchet coupling) hinged on said bracket 6 at 11' and actuated by a spring 12, so that when roller 8 is moved across the upper piece 1 3 of the pack of pieces 14 from the position shown in Fig.

1 towards spindle 1 (Fig. 3), it is prevented from rotating by the pawl 11 which penetrates between two teeth of the toothed wheel 10. Conversely, when it is moved in the opposite direction, from the position of Fig. 3 to that of Fig. 1, roller 8 is allowed to rotate about its own axis along the top piece 1 3 of the pack of pieces 1 4.

In this way, when roller 8 is in its outermost position, collar 4 rests on the pack of pieces 14 and when roller 8 moves away from this position towards block 3, as it is prevented from rotating by the pawl 11, it forms a fold on the piece 1 3 which is disposed on top of the pack 14 trapping it against a projection 3' of block 3 in a manner suitable to allow its grasping when the whole device is raised by a machine not shown in the figures.

Said bracket 6 is provided with two side ears which enclose the block 3, thereby preventing the rotation of the same block, of spindle 1 and of roller 8, so that said roller, during the rising of spindle 1, moves horizontally on the pack of pieces 1 4 and is guided with respect to block 3 against projection 3', thus causing a sure grasping of the top piece of the pack.

Fixed to spindle 1 is an electric contact 1 integral to block 3 which closes the switch 1 5 when roller 8 is at its outer position so that in this position the electric circuit which is closed by said switch causes said spindle to rise automatically by means of a known means not shown, thereby moving the roller on the pack 14 against the block, the piece being grasped.

A second switch not shown in the figures can be provided which causes roller 8 to return to its outer position, i.e. the position in which block 3 is resting on the pack of pieces after the grasped piece has been taken away.

Obviously the device of the present invention is susceptible of a number of modifications and changes without departing from the scope and spirit of the invention itself.

Claims (5)

1. A grasping device for pieces of textile material or the like piled up to form a pack comprising a rocking bracket carrying a roller covered with a material having a strong friction coefficient and coupled with ratchet means carried by said bracket so that when the roller is moved on the pack of pieces towards the vertical passing across the oscillation fulcrum of said bracket said roller is prevented from rotating by means of the ratchet coupling, while, when it is moved to the opposite direction, the roller can rotate about its own axis, said device being characterized in that said fulcrum is supported by a spindle arranged to move up and down within a block resting on the pack of pieces, so that when the roller moves towards the block which is still resting on the pack it causes the top piece to form a fold which is trapped between the roller itself and the block and which allows the piece to be picked up when the whole device is raised.

2. A grasping device according to claim 1, characterized in that the block is provided with a projection against which the piece is trapped by the roller.

3. A grasping device according to claim 1, characterized in that the spindle is provided at its lower portion with a collar which rests on the pack of pieces when the roller is at its outermost position, while it is substantially against the upper portion of the block for the raising thereof when roller is against the block itself, the piece being trapped therebetween.

4. A grasping device according to claim 1, characterized in that the rocking bracket is provided with two side ears which enclose the block so that when the roller is draged across the pack of pieces, it is guided with respect to the block against the block projection.

5. A grasping device according to claim 1, characterized in that a switch is provided which closes an electric circuit when the roller is at its outermost position, so that in this position the electric circuit is closed on a means which causes said spindle to rise automatically and therefore the roller to move across the pack against the block, the piece being trapped therebetween.