CN111032943A

CN111032943A - Cloth gripping chuck and cloth handling device

Info

Publication number: CN111032943A
Application number: CN201880051874.6A
Authority: CN
Inventors: 矢野诚; 矢部雄一郎
Original assignee: Purex Co Ltd
Current assignee: Purex Co Ltd
Priority date: 2017-08-31
Filing date: 2018-07-11
Publication date: 2020-04-17
Also published as: EP3677714A4; US20200224348A1; WO2019044191A1; KR20200027983A; EP3677714A1; JP2019044288A

Abstract

In a cloth gripping chuck and a cloth operating device capable of avoiding damage to a cloth and reducing falling of the cloth when the cloth is operated, the cloth gripping chuck (21) is provided with: a pair of holding claws (212, 213) arranged oppositely; and an opening/closing mechanism for relatively moving the pair of gripping claws (212, 213) closer to and away from each other, wherein each gripping claw (212, 213) has a protruding portion (214, 215) at the tip thereof, which protrudes toward the other gripping claw (213, 212) that is opposite to the other gripping claw, and the surface (214a, 215a) of the protruding portion (214, 215) on the base end side of the gripping claw (212, 213) is formed as a flat surface that is parallel to the direction in which the pair of gripping claws (212, 213) face each other, or is formed as an inclined surface that is inclined in the direction toward the base end side as the other protruding portion (215, 214) that faces each other.

Description

Cloth gripping chuck and cloth handling device

Technical Field

The present invention relates to a cloth gripping chuck for gripping a cloth and detachably holding the cloth in a cloth washing plant or the like, and a cloth handling apparatus for moving the cloth gripping chuck to perform operations such as lifting, pulling out, or delivering the cloth.

Background

In the automatic cloth stretching machine of patent document 1, for example, a plurality of cloth handling devices for performing operations such as lifting, pulling out, or delivering of a cloth are mounted on an automatic cloth stretching machine for stretching a cloth and a cloth smoothing machine for loosening a cloth block made of a plurality of cloths entangled with each other, which are used in a cloth washing plant or the like.

The chuck in such a cloth handling apparatus is configured to have a pair of gripping claws, and the gripping or releasing of the cloth is performed by opening and closing the pair of gripping claws using a driving mechanism such as an air cylinder or a motor.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-222724

Disclosure of Invention

As shown in fig. 41, a conventional cloth gripping chuck includes a chuck in which the entire gripping surfaces of gripping claws are flat and the entire gripping surfaces are in contact with each other in a fully closed state of the chuck. However, in the case of a chuck having such a shape, when a large amount of cloth is gripped or pulled up, the cloth often falls off. Further, since the tips of the gripping claws of the chuck are in close contact with each other in the fully closed state of the chuck, as shown in fig. 42, if the gripped fabric is about to fall off, the tips of the gripping claws may catch the fabric, for example, and cause damage such as fraying.

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a cloth gripping chuck and a cloth handling apparatus which can prevent damage to a cloth and reduce the falling of the cloth when the cloth is handled.

In order to achieve the above object, the present invention provides a cloth gripping chuck including a pair of gripping claws arranged to face each other and an opening/closing mechanism for relatively moving the pair of gripping claws toward and away from each other, wherein each gripping claw has a protruding portion at a distal end thereof, the protruding portion being formed on a surface of the gripping claw on a proximal end side thereof with a plane parallel to a direction in which the pair of gripping claws face each other, or with an inclined surface inclined in a direction toward the proximal end side as the protruding portion approaches the other opposing protruding portion.

In the cloth holding chuck according to the present invention, it is preferable that a gap is formed between the opposing protruding portions at the fully closed position of the pair of holding claws, and more preferably, the gap is set to be substantially equal to the thickness of the cloth to be held.

In the cloth holding chuck according to the present invention, it is preferable that at least one of the pair of holding claws is provided so as to be swingable around a swing axis extending in a direction orthogonal to both an extending direction from a proximal end to a distal end of the holding claw and the opposing direction.

The present invention is a cloth handling apparatus including a cloth gripping chuck having a pair of gripping claws arranged to face each other and an opening/closing mechanism for relatively moving the pair of gripping claws toward and away from each other, and a moving mechanism for moving the cloth gripping chuck, wherein each gripping claw has a protruding portion at a tip thereof, the protruding portion protruding toward the other gripping claw facing each other, and a surface of the protruding portion on a base end side of the gripping claw is formed as a flat surface parallel to a facing direction of the pair of gripping claws or as an inclined surface inclined toward the base end side as it goes toward the other protruding portion facing each other.

In the cloth material handling apparatus according to the present invention, it is preferable that a gap is formed between the opposed protruding portions at the fully closed position of the pair of gripping claws, and more preferably, the gap is set to be substantially equal to the thickness of the cloth material to be gripped.

In the cloth handling apparatus according to the present invention, it is preferable that at least one of the pair of gripping claws is provided so as to be swingable about a swing axis extending in a direction orthogonal to both an extending direction from a proximal end to a distal end of the gripping claw and the opposing direction.

Effects of the invention

In the cloth gripping chuck of the present invention, when a part of the cloth is brought into contact with the pair of gripping claws in the open posture and the pair of gripping claws are closed by the opening and closing mechanism, the part of the cloth is sandwiched between the gripping claws and the cloth operating device is moved upward from this state, for example, whereby the cloth can be lifted. At this time, when a load from the cloth is applied to the surface (back surface) of the protruding portion of the gripping claw on the base end side of the gripping claw, the back surface is formed as a flat surface parallel to the opposing direction of the pair of gripping claws at the fully closed position of the gripping claw or as an inclined surface inclined in a direction approaching the base end side as the other protruding portion is opposed, whereby the gripping claw is further swung in the closing direction, and a cloth portion inside the protruding portion is hooked on the back surface of the protruding portion. Therefore, the falling off (dropping) of the cloth Y is reduced.

In the cloth holding chuck according to the present invention, even when the holding claw is fully closed and a gap is maintained between the protruding portions, the protruding portions do not forcibly hold the cloth and are allowed to fall off when the cloth held by the cloth holding chuck is about to fall off, and therefore, the cloth can be more reliably prevented from being damaged by the holding claw. In addition, when the size of the gap is made substantially equal to the thickness of two pieces of cloth, the cloth can be prevented from falling off and from being damaged more reliably.

Drawings

Fig. 1 is an overall schematic view of an automatic cloth unfolding machine.

Fig. 2 is an enlarged perspective view of the supply conveyor and the lifting device in the automatic cloth spreading machine of fig. 1.

Fig. 3 is an enlarged perspective view of the supply conveyor and the lifting device in the automatic cloth spreading machine of fig. 1.

Fig. 4 is an enlarged perspective view of the supply conveyor and the lifting device in the automatic cloth spreading machine of fig. 1.

Fig. 5 is an enlarged perspective view of the temporary holding means and the corner end finding means of the cloth automatic unrolling machine of fig. 1.

Fig. 6 is an enlarged perspective view of the corner end finding device of the automatic cloth unfolding machine of fig. 1.

Fig. 7 is an enlarged perspective view of the corner end finding device of the automatic cloth unfolding machine of fig. 1.

Fig. 8 is an enlarged perspective view of the corner end finding device of the automatic cloth unfolding machine of fig. 1.

Fig. 9 is an enlarged perspective view of the corner end finding device of the automatic cloth unwinding machine of fig. 1.

Fig. 10 is an enlarged perspective view of the corner end finding device and the corner end obtaining device of the automatic cloth unfolding machine of fig. 1.

Fig. 11 is an enlarged perspective view of the corner-end obtaining device and the lateral pulling device in the automatic cloth unfolding machine of fig. 1.

Fig. 12 is an enlarged perspective view of a lateral pulling device of the automatic cloth unfolding machine of fig. 1.

Fig. 13 is an enlarged perspective view of a lateral pulling device in the automatic cloth stretching machine of fig. 1.

Fig. 14 is an enlarged perspective view of a lateral pulling device for the automatic cloth stretching machine of fig. 1.

Fig. 15 is an enlarged perspective view of the lateral pulling device, the double-position holding device, the edge finding conveyor, and the up-down reversing device of the automatic cloth stretching machine of fig. 1.

Fig. 16 is an enlarged perspective view of the double-position holding device, the edge finding conveyor and the up-down reversing device of the automatic cloth unwinding machine of fig. 1.

Fig. 17 is an enlarged perspective view of the double-position holding device, the edge finding conveyor and the up-down reversing device of the automatic cloth unwinding machine of fig. 1.

Fig. 18 is an enlarged perspective view of the double-position holding device, the edge finding conveyor and the up-down reversing device of the automatic cloth unwinding machine of fig. 1.

Fig. 19 is an enlarged perspective view of the double-position holding device, the edge finding conveyor and the up-down reversing device of the automatic cloth unwinding machine of fig. 1.

Fig. 20 is an enlarged perspective view of the double-position holding device, the edge finding conveyor and the up-down reversing device of the automatic cloth unwinding machine of fig. 1.

Fig. 21 is an enlarged perspective view of the edge finding conveyor and the vertical reversing device in the automatic cloth spreading machine of fig. 1.

Fig. 22 is an enlarged perspective view of the edge finding conveyor and the vertical reversing device in the automatic cloth spreading machine of fig. 1.

Fig. 23 is an enlarged perspective view of the edge finding conveyor, the vertical reversing device, the rollers, and the setting device in the automatic cloth stretching machine of fig. 1.

Fig. 24 is an enlarged perspective view of the edge finding conveyor, the vertical reversing device, the rollers, and the setting device in the automatic cloth stretching machine of fig. 1.

Fig. 25 is an enlarged perspective view of the edge finding conveyor, the vertical reversing device, the rollers, and the setting device of the automatic cloth stretching machine of fig. 1.

Fig. 26 is an enlarged perspective view of the roller and the setting device in the automatic cloth unrolling machine of fig. 1.

Fig. 27 is an enlarged perspective view of a roll for the automatic cloth unwinding machine of fig. 1.

Fig. 28 is an enlarged perspective view of the rollers, the advancing and retreating device, and the conveying conveyor of the automatic cloth stretching machine of fig. 1.

Fig. 29 is an enlarged perspective view of the rollers, the advancing and retreating device, and the conveying conveyor of the automatic fabric stretcher of fig. 1.

Fig. 30 is an enlarged perspective view of the advancing and retreating device and the conveying conveyor in the automatic fabric spreading machine of fig. 1.

Fig. 31 is an enlarged perspective view of the advancing and retreating device and the conveying conveyor in the automatic fabric spreading machine of fig. 1.

Fig. 32 is an enlarged perspective view of the advancing and retreating device and the conveying conveyor in the automatic fabric spreading machine of fig. 1.

Fig. 33 is an enlarged perspective view of the advancing and retreating device and the conveying conveyor in the automatic fabric spreading machine of fig. 1.

Fig. 34 is an enlarged perspective view of the conveying conveyor of the automatic fabric stretching machine of fig. 1 and a fabric folding machine in the next step.

FIG. 35 is a top view of a cloth gripping chuck in accordance with an embodiment of the present invention.

Fig. 36 shows an internal structure of the cloth gripping chuck of fig. 35, (a) shows a fully closed state of the gripping claws, and (b) shows a fully opened state of the gripping claws.

Fig. 37 is a view showing a state where the cloth gripping chuck of fig. 35 grips and lifts the cloth.

Fig. 38 is a view showing a state where the cloth is dropped from the gap between the protruding portions when the cloth holding chuck of fig. 35 holds and lifts the cloth.

Fig. 39 is a plan view showing a main part of a modification of the cloth holding clip of fig. 35.

Fig. 40 is a plan view showing a main part of a cloth holding chuck according to another embodiment of the present invention.

Fig. 41 is a view for explaining a problem when a cloth is lifted by using a conventional cloth holding chuck.

Fig. 42 is a view for explaining a problem when a cloth is lifted by using a conventional cloth holding chuck.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The cloth gripping chuck and the cloth handling apparatus having the same according to the present invention are suitable for lifting, pulling out, or delivering a cloth in an automatic cloth unwinding machine, a cloth smoothing machine, or the like provided in a cloth washing plant or the like, and the following description will be given by taking, as an example of use, a case where the cloth gripping chuck and the cloth handling apparatus having the same according to the embodiment are applied to the automatic cloth unwinding machine.

Fig. 1 shows an overall view of the cloth automatic unrolling machine, and fig. 2 to 34 show individual apparatus portions of the cloth automatic unrolling machine of fig. 1. In the following description, front, rear, right, left, up, and down directions are shown in the state of fig. 1.

As shown in fig. 1, the cloth automatic unfolding machine automatically unfolds cloth such as towels, sheets, quilts, pillow cases, bathrobes, etc. after washing and drying are mainly provided with a supply conveyor 1, a lifting device 2, a temporary holding device 3, a corner end finding device 4, a corner end acquiring device 5, a horizontal pulling device 6, a double-position holding device 7, an edge finding conveyor 8, an up-down reversing device 9, rollers 10, a setting device 11, a forward-backward device 12, a conveying conveyor 13, and a control device, not shown, for controlling the operations of the devices 1 to 13. In fig. 1, a suction conveyor a, a push-out device B, a return conveyor C, and a cloth folding machine D are illustrated as auxiliary or related devices. The return conveyor C returns the cloth dropped in the middle of the processing to the supply conveyor 1.

The automatic cloth unwinding machine operates substantially as follows. That is, the supply conveyor 1 supplies the cloth after the washing and drying is completed to the lower side of the lifting device 2, the lifting device 2 lifts the cloth to a predetermined height, the temporary holding device 3 receives and temporarily holds the cloth in the lifted state and moves the cloth to a transfer position to the corner end finding device 4, the corner end finding device 4 receives an arbitrary portion of the suspended cloth from the temporary holding device 3 and presents the corner end of the cloth, the corner end acquiring device 5 holds the corner end and moves the cloth to the side of the lateral pulling device 6 while hanging down and supporting the cloth, the lateral pulling device 6 laterally pulls the cloth to be substantially horizontal in the front-rear direction, and after the two position holding device 7 holds two positions of the vicinity of the corner end of the cloth in the lateral pulled state and the middle position separated from the corner end by a proper distance at the same height and moves the cloth to the upper side of the edge finding conveyor 8, releasing the center of the held cloth, moving the other part of the cloth held near the corner end by the double-position holding device 7 by the edge finding conveyor 8 to present one side edge of the long side of the cloth, holding the side edge of the long side of the cloth lowered from the edge finding conveyor 8 by the up-down reversing device 9, vertically reversing the cloth, and holding the cloth, picking up the side edge of the long side of the cloth from the up-down reversing device 9 by the picking-up device 11 moving in the left-right direction along the roller 10 above the roller 10, picking up the cloth from the up-down reversing device 9, picking up the cloth from the side edge of the long side of the cloth on the roller 10, conveying the cloth picked up by the roller 10 to leave the short end edge thereof and hanging down to the advancing-retreating device 12, and moving the cloth to the conveyor 13 in the unfolded state while holding the short edge of the cloth and retreating the short end edge of the cloth after picking up the short end edge of the cloth left on the roller 10, the transport conveyor 13 carries out the spread cloth and drops it into, for example, a cloth folding machine D in the next step.

As shown in fig. 1 to 3, the supply conveyor 1 can be continuously moved by a motor 1a during operation, and a block X of, for example, about 10 to 50 pieces of rectangular cloth Y, which is kept in a rolled state after washing and drying, is dropped on the supply conveyor 1. The supply conveyor 1 conveys the block X of the cloth Y to below the lifting device 2 (indicated by reference numeral X' in fig. 2). A suction conveyor a is provided at the end of the supply conveyor 1 in the conveying direction. The suction conveyor a includes a perforated belt a1, a suction fan a2 for sucking the cloth Y supplied onto the conveyor 1 by the perforated belt a1, and a motor A3 for driving the perforated belt a1 to rotate and convey the sucked cloth Y to a position directly below the lifting device 2 (indicated by reference numeral X ″ in fig. 3). A wall 1b for preventing the block X from falling from the supply conveyor 1 is provided upright near the terminal end of the perforated belt a 1. In addition, a pushing device B that pushes the cloth on the supply conveyor 1 toward the right below the lifting device 2 may be provided in addition to or instead of the suction conveyor a at the end of the conveying direction of the supply conveyor 1. The ejector B is composed of a cylinder B1 and an ejector rod B2 that advances and retracts by the cylinder B1.

The lifting device 2 includes a chuck 21 for holding an arbitrary portion of the cloth Y and a lifting device for lifting and lowering the chuck 21, and in the illustrated example, the lifting device includes a drive belt 23 and a motor 22. The lifting device may have any structure as long as it can lift and lower the cartridge 21 between a predetermined height and the conveying surface of the supply conveyor 1, and may have, for example, a chain structure or a structure including a slider unit that moves up and down on a guide rail. When the lifting device 2 moves the chuck 21 to the lowermost position (the position shown by the imaginary line and reference numeral 21' in fig. 4) by the drive belt 23 and the motor 22, the chuck 21 comes into contact with the fabric Y at the terminal end of the supply conveyor 1 and the chuck 21 holds the contact portion of the fabric Y. The cloth holding portion held by the chuck 21 may be any portion. When the chuck 21 is moved upward, the chuck 21 moves upward to a predetermined height (uppermost position) shown by a solid line in fig. 4 while holding the cloth Y by the chuck 21, and holds the cloth Y in a suspended state. At this time, two or more cloths Y may be held and lifted by the chuck 21.

As shown in fig. 1 and 4, the temporary holding device 3 includes a collet 31 and a moving device (telescopic cylinder 32) for moving the collet 31 forward and backward. When the chuck 21 of the lifting device 2 moves to the uppermost position or when the cloth Y held by the chuck 21 at the uppermost position is detected by a sensor (not shown), the stretching cylinder 32 of the temporary holding device 3 is stretched, the chuck 31 moves forward to a position (shown by 31') shown by an imaginary line in fig. 4, the vicinity of the upper end of the cloth Y lifted by the lifting device 2 is received by the chuck 31 of the temporary holding device 3 (at this time, the chuck 21 of the lifting device 2 releases the cloth Y), and then the stretching cylinder 32 is shortened and retreats to a predetermined position while holding the cloth Y suspended by the chuck 31 as shown by a solid line in fig. 4. In addition, in most cases, one of the corner ends of the cloth Y suspended by the chuck 31 is present at the lowermost end (shown by reference character Ya in fig. 4).

As shown in fig. 5 to 9, the corner finding device 4 includes: a chuck 41 that takes in the cloth Y suspended and held by the chuck 31 of the temporary holding device 3 at its retreated position; a retractable device (retractable cylinder 42) for advancing and retracting the chuck 41 forward and backward; a platen 43 on which a cloth Y is placed on an upper surface; a sensor 49, for example, a photoelectric tube, for detecting a terminal end (corner end Ya) of the cloth Y drawn on the platen 43; a platen 47 that sandwiches a central portion of the cloth Y on the platen 43 between the platen 43 and the platen 47; a telescopic cylinder 48 for moving the platen 47 up and down; a diagonal

end finding roller

44, 45; and a telescopic cylinder 46 that makes one corner-end finding roller 45 approach and separate from the other corner-end finding roller 44.

When the angular end finding device 4 is operated to the retreating position with the chuck 31 of the temporary holding device 3 holding the cloth Y as shown in fig. 5, the telescopic cylinder 42 is extended and the chuck 41 is advanced, the chuck 41 receives the cloth Y from the chuck 31 of the temporary holding device 3, then, as shown in fig. 6, the telescopic cylinder 42 is shortened and the chuck 41 pulls the cloth Y in a predetermined distance on the platen 43 while holding the cloth Y, then the chuck 41 releases the cloth Y, then, as shown in fig. 7, the angular end finding roller 45 located inside is lowered from the position indicated by reference numeral 45 ', the leading end portion of the cloth Y is sandwiched between the angular end finding roller 44 located near the leading end, and the platen 47 is lowered from the raised position indicated by reference numeral 47', the center portion of the cloth Y is sandwiched between the platen 47 and the platen 43, and in this state, as shown in fig. 8, the two angular end finding rollers 44, 45 are rotated in the arrow direction, accordingly, when the cloth Y hangs down and the terminal end portion (the corner end Ya) of the cloth Y drawn on the platen 43 is detected by the sensors 49, 49 (or the cloth Y is not detected by the sensors 49, 49 any more), the rotation speeds of the two corner end finding rollers 44, 45 are switched to low speeds. In this series of operations, when there are a plurality of the cloth materials Y, the other cloth materials Z fall except for one cloth material Y held between the platen 43 and the platen 47 at the terminal end. When the

other sensors

4a and 4a, which are, for example, phototubes, disposed between the two corner

edge finding rollers

44 and 45 detect the terminal end portion (corner edge Ya) of the fabric Y (or when the fabric Y is no longer detected by the

sensors

4a and 4 a), the rotation of the corner

edge finding rollers

44 and 45 is stopped, and the corner edge Ya of the fabric Y or the vicinity thereof is held by the corner

edge finding rollers

44 and 45, and the corner edge finding operation is completed.

In the illustrated example, after the cloth Y lifted by the lifting device 2 is temporarily held by the temporary holding device 3, the cloth Y is held by the chuck 41 of the corner-end finding device 4, but in another example not illustrated, the temporary holding device 3 may be omitted and the cloth Y lifted by the lifting device 2 may be directly held by the chuck 41 of the corner-end finding device 4.

As shown in fig. 10, the corner edge obtaining device 5 includes a collet 51 disposed below the corner

edge finding rollers

44 and 45, and a retracting device (a telescopic cylinder 52) for retracting the collet 51 in the right-left direction (see fig. 1) in a range directly below the contact portions of the corner

edge finding rollers

44 and 45. The corner-end obtaining device 5 acts in the following manner: when the diagonal

end finding rollers

44 and 45 of the diagonal end finding device 4 hold the diagonal end Ya of the fabric Y or its vicinity, the stretching cylinder 52 is stretched, the chuck 51 advances in the left direction as shown by the imaginary line in fig. 10, the chuck 51 holds the diagonal end Ya of the fabric Y slightly below, and the fabric Y is retreated to the right side (the side of the lateral pulling device 6) while holding the hanging fabric Y. Further, a sensor 53 for detecting the fabric Y is attached to the chuck 51, and the chuck 51 is operated after the sensor 53 detects that the chuck 51 approaches the fabric Y, whereby the fabric Y can be reliably held.

A platen 64 (see fig. 11) is provided below and in the rear vicinity of the collet 51 in a state where the telescopic cylinder 52 of the corner end obtaining device 5 is shortened. The platen 64 is used for supporting the terminal end side of the fabric Y when the vicinity of the upper end portion (corner end Ya) of the fabric is pulled up by the transverse pulling device 6 described later and moved to the rear side.

In the present embodiment, in order to make the one corner end Ya of the rectangular cloth Y appear, the corner end can be automatically found from the rectangular cloth in the rolled state using the lifting device 2, the temporary holding device 3, and the corner end finding device 4, but the work of finding the corner end of the cloth may be performed manually by an operator, for example, to find the one corner end from the cloth Y in the rolled state. In this case, the operator can directly take in the found cloth corner end Ya by the chuck 51 of the corner end obtaining device 5 or by the chuck 61 of the horizontal pulling device 6 described later.

As shown in fig. 11 to 14, the lateral pulling device 6 includes a chuck 61 and an advancing/retreating device for advancing and retreating the chuck 61 in the front-rear direction. In the illustrated example, the advancing and retreating device is constituted by a drive belt 63 that holds the chuck 61 and a motor 62 that advances and retreats the chuck 61 in the front-rear direction by rotating a pulley around which the drive belt 63 is wound. As shown in fig. 11, when the chuck 51 of the corner-end acquiring device 5 holds the fabric Y and retreats, the horizontal pulling device 6 advances the chuck 61 to a position shown by an imaginary line and reference numeral 61 ', and the chuck 61' at the advanced position holds a position slightly below the upper end portion (corner end Ya) of the fabric. Next, after the fabric Y is released by the chuck 51 of the corner end obtaining device 5, as shown in fig. 12, the chuck 61 is moved backward while the vicinity of the fabric corner end Ya is held by the chuck 61, and the fabric Y is pulled across the platen 64. Next, as shown in fig. 13, after the cloth is pulled laterally by a predetermined distance, the upper platen 65 is lowered from the raised position indicated by reference numeral 65' by the cylinder 66 to sandwich the cloth Y between the platen 64, and then the lateral pulling is continued, and when the sensor 67 disposed below the platen 64 detects the terminal end Yb of the cloth Y (or when the sensor 67 no longer detects the cloth Y), the lateral pulling speed is switched to a low speed. As shown in fig. 14, when the other sensor 68 disposed near the platen 64 detects the terminal end Yb of the fabric Y (or when the sensor 68 no longer detects the fabric Y), the lateral pulling is stopped. At this time, the cloth Y is in a state (triangular shape) in which the remaining two corner ends except the corner end Ya held by the chuck 61 and the corner end Yb pressed by the upper platen 65 are arranged in front and rear, and one side edge Yc on the long side is present in a hanging portion.

As shown in fig. 15, an edge finding conveyor 8 driven by a motor 81 is provided on the right side of the platen 64 and the upper platen 65. A plurality of (nine in the illustrated example) narrow belts 8a extending in the left-right direction are disposed in the edge finding conveyor 8 at intervals in the front-rear direction.

As shown in fig. 15 to 20, the two-position holding device 7 includes: two clips 71, 72 (hereinafter also referred to as an intermediate holding clip 71 and an angular holding clip 72) attached to the rear end and the front end of the connecting rod 70 extending in the front-rear direction, respectively; a lift cylinder 73 for raising and lowering the

chucks

71 and 72; and a forward/backward moving device for moving the

chucks

71 and 72 forward and backward to the left and right together with the lift cylinder 73. The advancing/retreating means is constituted by a drive belt 75 for holding the lift cylinder 73 in a suspended state and a motor 74 for rotating a pulley around which the drive belt 75 is wound, but any structure may be used as long as the

chucks

71 and 72 can be moved in the left-right direction. The distance between the

chucks

71, 72 can be appropriately changed according to the size of the cloth Y to be processed, for example, by using a connecting rod 70 whose length can be adjusted, or by making the mounting position of the

chucks

71, 72 to the connecting rod 70 variable.

As shown in fig. 15, the corner holding clip 72 is positioned to hold the front end part (corner end) Yb of the fabric Y stretched by the stretching device 6, and the middle holding clip 71 is positioned to hold a suitable portion of the rear middle part of the fabric Y stretched.

The lift cylinder 73 causes the

chucks

71 and 72 to stand by at a position above the cloth Y being stretched in the shortened state (the state shown by the solid line in fig. 15), and causes the

chucks

71 and 72 to descend to a position capable of holding the upper edge of the cloth Y being stretched in the extended state as shown by the imaginary line in fig. 15.

When the two-position holding device 7 is lowered by the extension of the lift cylinder 73, as shown in fig. 16, the corner holding collet 72 holds the front end portion (corner end) Yb of the cloth Y, and the middle holding collet 71 holds the middle portion of the rear side of the cloth Y. At this time, as shown in fig. 15, the opening degree of the chuck 69 provided in the vicinity of the rear side of the upper platen 65 is reduced from the largely opened state shown by reference numeral 69', and the fabric Y can be easily held by the corner holding chuck 72. Then, the cloth Y is released from being held or bound by the chuck 61, the upper platen 65, and the chuck 69 by the lateral pulling device 6. As shown in fig. 17, the double-position holding device 7 is then moved toward the terminal end side of the edge finding conveyor 8 by the advancing and retreating device at a position above the edge finding conveyor 8. The belt of the edge finding conveyor 8 moves in the direction of the arrow in fig. 17, and the triangular portion (near Yc) of the fabric Y can contact the conveyor 8. The triangular portion is in a state of following (following) the moving direction of the conveyor 8 by the blowing action of the blower 82 provided between the upper and lower belts of the conveyor 8.

Next, as shown in fig. 18, the chuck 71 at the rear of the double-position holding device 7 releases the cloth Y, and one side (a portion at the rear side of the corner end Yb) of the cloth Y falls onto the moving belt of the edge finding conveyor 8. Since the leading end (the corner end Yb) of the cloth Y is held by the corner holding chuck 72, only the falling portion of the cloth Y moves to the right side as shown in fig. 19. When the falling portion of the cloth Y moves a predetermined distance, one side edge Yc of the long side of the cloth Y is disposed substantially orthogonal to the moving direction of the edge finding conveyor 8. When this arrangement is established, as shown in fig. 20, the other chuck 72 releases the cloth Y and the cloth Y is completely dropped onto the edge finding conveyor 8. Two sensors 83 for detecting the leading side edge Yc of the cloth Y transferred on the edge finding conveyor 8 are provided near the terminal end of the edge finding conveyor 8, and when the sensors 83 detect the cloth Y, the edge finding conveyor 8 is switched to a low speed.

As shown in fig. 21, the up-down reversing device 9 includes: two

chucks

92, 93 arranged near the end of the edge finding conveyor 8 and gripping one side edge Yc on the long side of the cloth Y; two

sensors

94, 95 provided near the

respective chucks

92, 93; a reverse shaft 96 that supports the

chucks

92, 93; and a rotation cylinder 91 that rotates the reversing shaft 96. Any mechanism may be used as long as the cloth Y gripped by the two

chucks

92, 93 can be reversed, and a motor for rotating the reversing shaft 96 forward and backward may be used instead of the rotating cylinder 91. The two chucks 92 and 93 are configured to operate independently of each other based on detection signals of the side edge Yc of the fabric Y detected by the

sensors

94 and 95, and thereby the side edge Yc of the fabric Y can be held straight between the two

chucks

92 and 93.

The vertical reversing device 9 operates as follows. First, as shown in fig. 20, the

chucks

92 and 93 stand by in a substantially horizontal (slightly upward inclined) posture until the leading side edge Yc of the fabric transferred on the edge finding conveyor 8 is detected by the

sensors

94 and 95, and when the leading side edge Yc of the fabric Y transferred on the edge finding conveyor 8 is detected by the

sensors

94 and 95, the

chucks

92 and 93 hold the leading side edge Yc of the fabric based on the detection signals from the

sensors

94 and 95. Then, immediately after the rotating cylinder 91 is shortened, the

chucks

92 and 93 rotate downward at high speed while holding the side edge Yc of the cloth, and assume the downward posture shown in fig. 22. At this time, the cloth Y held by the

chucks

92 and 93 is rapidly thrown downward (a smoothing action is generated in the short side direction of the cloth) and hangs down. Then, the

respective chucks

92 and 93 holding the side edge Yc of the fabric in the downward posture release the respective holding portions of the side edge Yc at the time of transfer to the

respective chucks

111 and 112 of the mounting device 11 described later, and immediately thereafter, rotate upward to return to the original standby position.

As shown in fig. 23, a roller 10 and a setting device 11 for setting the cloth Y on the roller 10 are provided in a positional relationship in which the setting device 11 is located above and the roller 10 is located below the front side portion of the edge finding conveyor 8.

The setting device 11 includes: a forward/backward table 110 facing the vertical reversing device 9; two

chucks

111, 112 arranged on both sides of the advancing-retreating table 110, and configured to receive the cloth Y from the

chucks

92, 93 of the vertical reversing device 9; and chuck

sensors

113, 114. The setting device 11 is moved forward and backward in the left-right direction (the direction of the rotation axis of the roller 10) by the advancing and retreating device. In the illustrated example, the advancing/retreating device is constituted by a drive belt 116 that holds the advancing/retreating table 110 and a motor 115 that rotates a pulley around which the drive belt 116 is wound, but any structure may be used as long as the

chucks

111, 112 can be advanced and retreated in the left-right direction, and for example, an advancing/retreating cylinder may be used.

The setting device 11 moves from the standby position shown in fig. 23 toward the cloth Y held by the vertical reversing device 9, and when the

chuck sensors

113 and 114 detect the cloth Y, as shown in fig. 24, the

chucks

111 and 112 close to both side portions of the advancing/retreating stage 110 to hold the cloth Y. Here, the holding position of the cloth Y held by the

chucks

111 and 112 is a position close to the holding position of the cloth Y held by the

chucks

92 and 93 of the vertical reversing device 9. Further, the two

chucks

111 and 112 may be configured to operate independently of each other, so that the portion of the side edge Yc of the fabric Y between the two

chucks

111 and 112 can be kept more straight. After the cloth Y is delivered, the vertical reversing device 9 is reversed to return to the original position as shown in fig. 25, and retreats from the rail of the mounting device 11. Since the roller 10 is disposed so that the rotation axis thereof is parallel to the advancing and retreating direction of the setting device 11, when the setting device 11 which holds the cloth Y while hanging down is retreated, the cloth Y is set on the roller 10 and hangs down from the roller 10 as shown in fig. 25. At this time, the side edge Yd on the opposite side to the side edge Yc on the long side held by the

chucks

111 and 112 is detected by the sensor 101, and after a predetermined time has elapsed since the detection, the

chucks

111 and 112 release the fabric Y. The predetermined time is set as appropriate so that the

chucks

111 and 112 release the fabric Y when the widthwise center of the fabric Y substantially coincides with the widthwise center of the roller 10. The setting device 11 also continues to retreat by a predetermined distance after the

chucks

111 and 112 release the cloth Y.

As shown in fig. 26, the roller 10 is composed of a1 st partial roller 102 and a2 nd partial roller 103 which are disposed adjacent to each other on the same axis. The 1 st segment roller 102 is connected to a motor 104 via a drive belt 105 and is rotationally driven by the motor 104. The 2 nd partial roller 103 is connected to a motor 106 via a drive belt 107 and is rotationally driven by the motor 106. The rotation directions and rotation speeds of the

motors

104 and 106 can be independently controlled, and are preferably independently controlled so that the direction of the fabric Y on the roller 10 is corrected to a correct direction (for example, a direction in which the longitudinal direction of the fabric Y coincides with the front-rear direction) based on detection signals from a plurality of

sensor groups

108 and 109 arranged below the

rollers

102 and 103 in parallel with the rotation axes of the rollers as shown in fig. 27. For example, as shown in fig. 26, when the cloth Y is obliquely placed on the roller 10 and only the sensor group 109 among the

sensor groups

108 and 109 detects the side edge Ye on the short side of the cloth Y as shown in fig. 27, based on the detection result, the stop, the normal rotation, and the reverse rotation of the 1 st partial roller 102 and the 2 nd partial roller 103 are repeated until the side edge Ye is parallel to the

sensor groups

108 and 109 and both

sensor groups

108 and 109 simultaneously detect the side edge Ye on the short side of the cloth Y. In the illustrated example, each of the

sensor groups

108 and 109 is formed by five sensors, but the number of sensors is not limited to this, and may be four or less, six or more depending on the width of the fabric Y to be processed, or may be a sensor that switches the operation depending on the fabric Y to be processed.

The advancing and retreating device 12 transfers the fabric Y, which has been oriented correctly on the roller 10, to the transport conveyor 13, and as shown in fig. 28, includes: a holding section having a holding width larger than the width of the fabric Y and holding an end of a short side of the fabric Y; and an advancing and retreating mechanism for advancing and retreating the grip portion in the front-rear direction. In the illustrated example, the gripping portion is composed of a holding base 123a inclined toward the roller 10 and a holding plate 123b opened and closed with respect to the holding base 123a by a cylinder 124 or the like. The advancing and retreating mechanism is constituted by a drive belt 122 coupled to the holding base 123a and a motor 121 that rotates a pulley around which the drive belt 122 is wound.

When the cloth Y on the roller 10 is transferred to the conveying conveyor 13 by the advancing and retreating device 12, as shown in FIG. 28, the 1 st partial roll 102 and the 2 nd partial roll 103 are rotated simultaneously and at the same speed toward the advancing/retreating device 12 side, so that the side edge Ye of the cloth Y located near the

sensor groups

108 and 109 approaches the advancing/retreating device 12 side, further, as shown in FIG. 29, the grip portion of the advancing-retreating device 12 is advanced, the tip of the holding base 123a of the grip portion in the state where the holding plate 123b is opened is pressed against the air blowing member 10a provided below the roller 10, the part of the roller 10 on the side of the fabric Y conveyor 13 is sandwiched between the front end of the holding base 123a and the air blowing member 10a, in this state, as shown in fig. 30, the air is blown out from the air blowing means 10a, and the 1 st partial roller 102 and the 2 nd partial roller 103 are further rotated toward the advancing and retreating device 12 side. The side edge Ye of the cloth Y is thereby placed on the holding base 123 a. Then, as shown in fig. 31, the holding plate 123b is closed, and the side edge Ye of the cloth Y is held between the holding plate and the holding base 123 a. The portion of the cloth Y other than the portion held by the holding base 123a and the holding plate 123b of the grip portion hangs down from the holding base 123 a. In this state, as shown in fig. 32, the grip portion of the advancing-retreating device 12 is moved to the conveying conveyor 13 side. After the grip portion is retracted by a predetermined distance, the holding plate 123b is opened again as shown in fig. 33, and the cloth Y is carried onto the conveying conveyor 13. Further, the grip portion of the advancing-retreating device 12 is also continuously retreated by a predetermined distance after the holding plate 123b releases the cloth Y.

As shown in fig. 33, the conveying conveyor 13 includes: a belt 133 having a plurality of through holes; a motor 132 that drives a belt 133; and a suction fan 131 for sucking the cloth Y on the belt 133 through a through hole formed in the belt 133. By sucking the fabric Y on the conveying conveyor 13 in this manner, the side edge Ye of the fabric Y held by the grip portion of the advancing and retreating device 12 can be dropped onto the conveying conveyor 13 and smoothly transferred. Then, as shown in fig. 34, the transport conveyor 13 carries out the fabric Y and transports (drops) the fabric Y to the next step (here, the fabric folding machine D). Further, the transport conveyor 13 may not drive the belt 133 when the grip portion of the advancing-retreating device 12 transfers the fabric Y onto the transport conveyor 13, but the belt 133 is preferably driven from the viewpoint of increasing the number of processed sheets.

According to the automatic cloth spreading machine having the above-described configuration, by simply throwing the washed and dried cloth Y onto the supply conveyor 1, the cloth Y can be automatically spread and conveyed (thrown) to the next process by the lifting device 2, the temporary holding device 3, the corner end finding device 4, the corner end acquiring device 5, the horizontal pulling device 6, the two-position holding device 7, the edge finding conveyor 8, the vertical reversing device 9, the rollers 10, the setting device 11, the advancing and retreating device 12, the conveying conveyor 13, and the like.

Next, an embodiment of the cloth holding chuck of the present invention will be described in detail with reference to fig. 35 to 40. In the above-described example of the automatic cloth unwinding machine, the cloth gripping chucks of the embodiment can be applied to the

chucks

21, 31, 41, 51, 61, 71, 72 and the like in the lifting device 2, the temporary holding device 3, the corner end finding device 4, the corner end obtaining device 5, the lateral pulling device 6, the two-position holding device 7 and the like, which are the cloth handling devices, respectively. In this case, the lifting device of the lifting device 2, the advancing and retreating device of the temporary holding device 3, the advancing and retreating device of the corner end finding device 4, the advancing and retreating device of the corner end obtaining device 5, the advancing and retreating device of the lateral pulling device 6, and the lift cylinder 73 and the advancing and retreating device in the two-position holding device 7 correspond to the moving mechanism of the cloth handling apparatus of the present invention. In the following description, the cloth handling apparatus of the present invention is described based on an example in which the cloth handling apparatus is applied to the lifting device 2.

First, fig. 35 is a plan view showing a cloth holding chuck according to an embodiment of the present invention, and the cloth holding chuck 21 according to the embodiment includes a main body 211 and a pair of holding

claws

212 and 213 which are held by the main body 211, are arranged to face each other, and can relatively approach and separate from each other. In the illustrated example, the two

gripping claws

212 and 213 are configured to be opened and closed by being swung about swing axes x1 and x2 (schematically indicated by dots in the figure). However, in a modification not shown, one of the gripping

claws

212 and 213 may be swingable, and the other

gripping claw

213 and 212 may be fixed, so that the one

gripping claw

212 and 213 may be moved toward and away from the other

gripping claw

213 and 212. The swing axes x1, x2 extend in a direction perpendicular to both the extending direction (the direction indicated by the one-dot chain line in fig. 35) from the proximal ends to the distal ends of the gripping

claws

212, 213 and the above-described opposing direction.

At the tip of each of the gripping

claws

212, 213, there are formed projecting

portions

214, 215 projecting toward the other

gripping claw

213, 212 facing each other, and each of the gripping claw portions on the outer side of the main body 211 has a substantially L-shape in plan view. The protruding

portions

214 and 215 are formed separately from the

claw bodies

216 and 217 that protrude straight from the main body 211, but may be formed integrally with the

claw bodies

216 and 217. The

claw bodies

216 and 217 and the

extension portions

214 and 215 can be formed of different materials by being separated from each other. For example, the

claw bodies

216 and 217 may be formed of a high-strength material, for example, a metal such as carbon steel, and the

extension portions

214 and 215 may be formed of an easily moldable material, for example, a synthetic resin. Further, by separating the

pawl bodies

216, 217 and the

extension portions

214, 215, the

extension portions

214, 215 can be replaced with different sizes and shapes depending on the use application. The protruding

portions

214 and 215 may be detachably fixed to the

pawl bodies

216 and 217 via fixing members such as screws and bolts, or may be fixed using an adhesive or the like.

In this regard, it is important that surfaces (side surfaces of the main body 211, hereinafter also referred to as "back surfaces") 214a and 215a of the protruding

portions

214 and 215 on the base end sides of the gripping

claws

212 and 213 are formed as planes parallel to the opposing direction of the pair of gripping claws 212 and 213 (in fig. 35, planes orthogonal to the extending direction indicated by the one-dot chain line). In addition, in a more advantageous aspect, a gap g is formed between the opposed protruding

portions

214, 215 at the fully closed position of the pair of holding

claws

212, 213. In a more preferable embodiment, the gap g is set to be substantially equal to the thickness of the two tensors of the cloth gripping the object. Here, the "fully closed position" indicates a position where the pair of

gripping claws

212 and 213 are closest to each other in structure.

Fig. 36 shows a driving unit as an opening/closing mechanism provided inside the main body 211 and configured to swing the pair of

gripping claws

212 and 213 about swing axes x1 and x 2. As shown in fig. 36 (a), the grip claw portion inside the main body 211 is also bent toward the

other grip claws

212 and 213, and the

grip claws

212 and 213 are formed into a substantially コ shape as a whole. The gripping

claws

212 and 213 are swingably held by the main body 211 via fulcrum pins 218 and 219 serving as swing axes x1 and x 2. Further, notches 221 into which drive pins 222b formed at the distal ends of piston rods 222a of cylinders 222 to be described later are pushed are formed in end portions of the gripping

claws

212 and 213 located on one side in the main body 211.

The driving unit is constituted by a cylinder 222 that advances and retracts a piston rod 222a by the pressure of air in the illustrated example. Fig. 36 (b) shows a state in which the piston rod 222a is moved in and out to simultaneously swing the two

gripping claws

212 and 213 about the fulcrum pins 218 and 219, thereby opening the gripping

claws

212 and 213. Any known drive mechanism such as a solenoid or a ball screw mechanism may be used as the drive unit as long as the

grippers

212 and 213 can be swung.

In the cloth gripping chuck 21 of the present embodiment, as shown in fig. 37, when a part of the cloth Y is brought into contact with the pair of

gripping claws

212 and 213 in the open posture and the piston rod 222a of the cylinder 222 is retracted, the pair of

gripping claws

212 and 213 are closed by swinging around the fulcrum pins 218 and 219, a part of the cloth Y is sandwiched between the gripping claws, and the lifting device 2 as the cloth operating device is moved upward from this state, whereby the cloth Y can be lifted. At this time, when a load is applied from the cloth Y to the

back surfaces

214a and 215a of the

extension portions

214 and 215 of the gripping

claws

212 and 213, the

back surfaces

214a and 215a are formed as flat surfaces parallel to the opposing direction of the pair of

gripping claws

212 and 213 at the fully closed position, and the gripping

claws

212 and 213 are further swung in the closing direction, whereby the cloth portion on the inner side (main body side) than the

extension portions

214 and 215 is hooked on the

back surfaces

214a and 215a of the

extension portions

214 and 215. Therefore, the falling off (dropping) of the cloth Y is reduced.

Further, according to the cloth holding chuck 21 of the present embodiment, since the gap g is maintained between the protruding

portions

214 and 215 even in the fully closed position of the holding

claws

212 and 213, as shown in fig. 38, when the cloth Y held by the cloth holding chuck 21 is about to come off, the protruding

portions

214 and 215 do not forcibly hold the cloth Y but allow the cloth Y to come off, and thus a situation in which the cloth Y is damaged by the holding

claws

212 and 213 can be avoided. Further, by making the size of the gap g substantially equal to the thickness of two pieces of the cloth Y, the cloth Y can be prevented from falling off and damage to the cloth Y can be prevented more reliably.

Fig. 39 is a plan view showing a main part of a modification of the cloth holding chuck 21 shown in fig. 35 to 38. In the cloth holding chuck 21 of the present modification, the

back surfaces

214a and 215a of the projecting

portions

214 and 215 are formed as inclined surfaces inclined in a direction approaching the main body 211 side as the projecting

portions

214 and 215 face each other, and the structure is different from that of the cloth holding chuck described with reference to fig. 35 to 38, and the other structure is the same. In this way, even when the

back surfaces

214a and 215a of the

extension portions

214 and 215 are formed by inclined surfaces, the fabric Y can be caught between the

extension portions

214 and 215 when the fabric Y is held, and therefore, the fabric Y can be prevented from falling off. Further, the inclination angle θ of the

back surfaces

214a, 215a with respect to the direction in which the

claw bodies

216, 217 protrude from the body 211 is preferably 75 ° or more and 90 ° or less. This is because if the inclination angle of the

back surfaces

214a and 215a is smaller than 75 °, the cloth Y is excessively caught by the

extension portions

214 and 215, and as a result, the cloth Y may not be smoothly released from the cloth holding clip 21.

Fig. 40 is a plan view showing a main part of a cloth holding chuck according to another embodiment of the present invention. In the above embodiment, the gripping

claws

212 and 213 are configured to be opened and closed by swinging about the swing axis, but the cloth gripping chuck of the present embodiment is configured to be opened and closed by sliding the pair of

gripping claws

212 and 213 in the opposing direction.

That is, the cloth holding chuck mainly includes: a guide rail 224 laid along the front side surface of the main body 211; a pair of

sliders

225, 226 traveling on the guide rail 224; a driving unit, not shown, provided inside the main body 211 and driving the

sliders

225 and 226; and

gripping claws

212, 213 fixed to the

respective sliders

225, 226. Any known drive mechanism such as an air cylinder, a solenoid, and a ball screw mechanism may be used as the drive unit as long as the

sliders

225 and 226 can be moved along the guide rail 224. Since the respective holding

claws

212 and 213 have the protruding

portions

214 and 215, and the cloth portions on the inner side (the main body 211 side) than the protruding

portions

214 and 215 are caught by the

back surfaces

214a and 215a of the protruding

portions

214 and 215 to reduce the falling-off (dropping-off) of the cloth Y, and the fully closed position of the holding

claws

212 and 213 maintains a gap between the protruding

portions

214 and 215 to prevent damage caused by the falling-off of the cloth Y, the detailed description thereof is omitted.

Industrial applicability

According to the present invention, a cloth gripping chuck and a cloth handling apparatus can be provided which can prevent damage to a cloth and reduce the falling of the cloth when the cloth is handled.

Description of the reference numerals

1 supply conveyor

2 hoisting device

3 temporary holding device

4-angle end finding device

5-corner end acquisition device

6 horizontal pulling device

7 two-position holding device

8 edge finding conveyor

9 vertical reversing device

10 roller

11 placing device

12 advancing and retreating device

13 conveying conveyor

21 cloth gripping chuck

211 main body

212. 213 gripping claw

214. 215 projecting part

214a, 215a back side

216. 217 jaw body

218. 219 fulcrum pin

221 cut

222 cylinder

222a piston rod

222b drive pin

224 guide rail

225. 226 slider

g gap

x1, x2 axis of oscillation

Claims

1. A cloth gripping chuck is provided with: a pair of holding claws arranged oppositely; and an opening/closing mechanism for relatively moving the pair of gripping claws toward and away from each other, wherein the cloth gripping chuck is characterized in that,

each gripping claw has a protrusion at a front end thereof protruding toward the other opposing gripping claw,

the surface of the protruding portion on the proximal end side of the gripping claws is formed as a flat surface parallel to the opposing direction of the pair of gripping claws or as an inclined surface inclined in a direction approaching the proximal end side as the other protruding portion becomes opposed.

2. A cloth gripping chuck according to claim 1,

at the fully closed position of the pair of gripping claws, a gap is formed between the opposed protruding portions.

3. A cloth gripping chuck according to claim 2,

the gap is set to be substantially equal to the thickness of the two tensors of the cloth gripping the object.

4. A cloth gripping chuck according to any one of claims 1 to 3,

at least one of the pair of gripping claws is provided swingably with a swing axis as a center, the swing axis extending in a direction orthogonal to both an extending direction from a proximal end to a distal end of the gripping claw and the opposing direction.

5. A cloth handling device is characterized by comprising:

the cloth gripping chuck of any one of claims 1 to 4; and a moving mechanism for moving the cloth holding chuck.