JPH07309576A - Holding device - Google Patents

Abstract

PURPOSE:To provide a holding device which is free from the occurrence of the position deflection of each top end of a fixed nipping holding piece and a movable nipping holding piece regardless of the dimension of the conveyed member to be held. CONSTITUTION:Concerning a holding device which is equipped with a fixed nipping holding piece 21 installed on the working attachment of a construction machine and a movable nipping holding piece 24 which can be attached and detached for the fixed nipping holding piece 21 and holds a conveyed member 201 between both the nipping holding pieces 21 and 24, an attaching/detaching mechanism 23 which attaches and detaches the movable nipping holding piece 24 in a straight line form for the fixed nipping holding piece 21, maintaining the state where the straight line joining the top end of the fixed nipping holding piece 21 and the top end of the movable nipping holding piece 24 is set almost parallel to the nipping holding direction of the conveyed member 201 is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gripping device for use in, for example, assembling a steel frame, and more particularly to a gripping device for gripping a carrier such as a steel frame between a pair of holding pieces.

[0002]

2. Description of the Related Art A conventional gripping device of this type is used, for example, in a handling machine for assembling a steel frame based on a hydraulic excavator. Kaisho 63-219
The one disclosed in Japanese Patent Publication No. 730 is known. FIG. 8 shows the gripping device disclosed in Japanese Utility Model Laid-Open No. 52324/1993, which is the arm 12 connected to the hydraulic excavator body.
It is attached to the tip of 3. Reference numeral 101 denotes a pair of holding pieces rotatably connected to the frame 102, 103 denotes a holding piece opening / closing cylinder interposed between the holding pieces 101, and the holding piece 101 is closed by the extension of the cylinder 103. The carrier material 201 such as H steel is gripped, and the clamping piece 101 is opened by the contraction of the cylinder 103 to release the carrier material 201.

Further, the one disclosed in Japanese Patent Laid-Open No. 63-219730 has a frame 111 as shown in FIG.
Pair of clamping pieces 112a, 112 rotatably connected to each other
b and a holding piece opening / closing cylinder 113, and the cylinder 113 is fixed to the frame 111. Cylinder 1
The tip of the piston rod 13 is connected to one holding piece 112a, and the holding piece 112a is connected to the other holding piece 112b via a link 114. Cylinder 113
Is extended, the gripping piece 112a is rotated clockwise in the drawing, and the gripping piece 112b is rotated via the link 114.
Rotates counterclockwise, and as a result, both gripping pieces 112
The conveying material 201 is gripped by a and 112b.

By the way, in both of the gripping devices of the above-mentioned two examples, both of the sandwiching pieces are operated at the same time. Therefore, in order to allow the sandwiching pieces to grip the conveying material 201, the conveying material 2 is previously prepared.
01 must be aligned so that it is centered on both clamps. This alignment usually takes time for the operator to perform visual examination, and there is a problem in that it is inaccurate.

Therefore, in order to facilitate the above alignment, one gripping piece is fixed, and the other gripping piece is moved with respect to the fixed gripping piece to grip the conveying material 201 (piece. Actuated gripping devices) have been proposed. Hereinafter, a conventional example of the one-sided gripping device will be described with reference to FIG. In FIG. 10, the boom 122 and the arm 123 are sequentially connected to the hydraulic excavator body 121, and the one-sided gripping device 130 is connected to the tip of the arm 123 via the bracket 124 and the turntable 125.
In addition, 126 is a boom cylinder that drives the boom 122, 127 is an arm cylinder that drives the arm 123,
128 is a wrist cylinder that drives the gripping device 130.

Reference numeral 131 denotes a frame on the side of the gripping device which is connected to the turntable 125.
A fixed holding piece 132 having a holding portion 132 a is attached to 31. The lever 1 is provided on the upper part of the fixed holding piece 132.
33 is rotatably connected, and the movable holding piece 134 has a holding portion 132 of the fixed holding piece 132 on one end side of the lever 133.
It is rotatably connected so as to face a. further,
The piston rod of the cylinder 135 fixed to the lower part of the fixed holding piece 132 is connected to the other end of the lever 133.

When the cylinder 135 is extended, the lever 1
33 rotates, the movable holding piece 134 is driven toward the holding portion 132a of the fixed holding piece 132, and the conveying material 201 is held between the holding piece 134 and the holding portion 132a. In this way, if the gripping device is of the one-acting type, it is sufficient to bring the conveying material 201 into contact with the sandwiching portion 132a of the fixed sandwiching piece 132 when gripping the conveying material 201. Pre-positioning can be done easily.

[0008]

By the way, by using the handling machine having the above-mentioned gripping device, the conveying material 201 can be obtained.
Often, the work of gripping and placing it horizontally along a vertical wall as shown in FIG. However, in the gripping device shown in FIG.
Since the movement of 4 is an arc movement, as shown in FIG.
Depending on the amount of rotation of the lever 133, a positional deviation L occurs between the tip of the holding portion 132a and the tip of the movable holding piece 134. Figure 1
In the case of gripping a large conveying material 201 as shown in 0, there is no problem because the positional deviation L is small, but FIG.
In the case of the small conveying material 201 as shown in Fig. 6, the positional deviation L
Becomes larger, and as described above, the conveying material 20 is moved along the vertical wall.
This will hinder the work of placing 1.

An object of the present invention is to provide a gripping device in which the tip ends of the fixed gripping piece and the movable gripping piece are not displaced regardless of the size of the conveying material to be gripped.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to FIG. 1 showing an embodiment. In the present invention, a fixed holding piece 21 attached to a work attachment of a construction machine and a fixed holding piece 21 separated from the fixed holding piece 21. With a movable holding piece 24 that can be contacted,
It is applied to a gripping device that grips the conveying material 201 between the sandwiching pieces 21 and 24. The movable holding piece 24 is linear with respect to the fixed holding piece 21 while maintaining a state in which the straight line connecting the tip of the fixed holding piece 21 and the tip of the movable holding piece 24 is substantially parallel to the gripping direction of the conveying material 201. Separation mechanism 2 to separate and contact
3 to solve the above problems. In particular, the invention of claim 2 constitutes the connecting / disconnecting means by the cylinder 23 including the cylinder tube 23a fixed to one of the holding pieces and the piston rod 23b fixed to the other holding piece. . Further, the invention of claim 3 is, for example, as shown in FIG. 3, a fixed side rack gear 42 which is integrated with the fixed holding piece 31 and extends in the holding direction of the conveying material 201.
And the movable holding piece 34, and the fixed side rack gear 4
2, a movable-side rack gear 43 extending in parallel with 2, a cylinder tube 33a fixed to the fixed sandwiching piece 31, and a cylinder 33 including a piston rod 33b having a pinion gear 41 meshing with the fixed-side and movable-side rack gears 42 and 43. The connecting / disconnecting means is configured by. Further, the invention of claim 4 is, for example, as shown in FIGS. 5 and 6, a guide rail 6 for guiding the movement of the movable holding piece 64.
2a, 62b, and the guide rails 62a, 62b and the movable holding piece 64, which are interposed between the guide rails 62a, 62b.
62b and the movable holding piece 64 are further provided with a slide member 65 having a contact surface that makes surface contact with each other.
Furthermore, the invention of claim 5 is, for example, as shown in FIG. 7, a positioning stopper 71 for positioning the conveying material 201 to be gripped with respect to the fixed sandwiching piece 61 ′, and the position of this stopper 71. The position adjusting mechanism 72 for adjusting between the base end portion and the tip end portion of 61 'is further provided.

[0011]

When the separating / connecting mechanism 23 is operated, the movable holding piece 24 is moved.
Is linearly driven toward the fixed sandwiching piece 21, and the conveying material 201 is held between both sandwiching pieces. Here, since the movable gripping piece is driven while maintaining a state in which the straight line connecting the tip of the fixed gripping piece and the tip of the movable gripping piece is substantially parallel to the gripping direction of the conveying material 201, regardless of the driving amount. The displacement L (FIG. 11) does not occur at the tips of both holding pieces. In addition,
In the section of means and action for solving the above problems for explaining the configuration of the present invention, the drawings of the embodiments are used to make the present invention easier to understand, but the present invention is thereby limited to the embodiments. is not.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 (a) is a front view of a gripping device according to the present invention,
FIG. 1B is a right side view of the same, and FIG. 2 is an enlarged plan view seen from the line II-II of FIG. The turntable 2 is rotatably connected to the arm tip of the hydraulic excavator as shown in FIG. 10 via the plate 1, and the gripping device 100 is mounted on the turntable 2. Gripping device 100
Has a pair of gripping mechanisms 20 symmetrically attached to the turntable 2 via the base plate 10. Hereinafter, the gripping mechanism 20 will be described in detail.

A fixed holding piece 21 fixed to the base plate 10 has a holding portion 21a formed at the lower end thereof and a cylinder guide portion 21b integrally formed at the upper end thereof, and the holding portion 21a and the guide portion are formed. A pair of left and right guide rails 22a and 22b are arranged between 21b. Both ends of the pair of guide rails 22a and 22b are fixed to the sandwiching portion 21a and the cylinder guide portion 21b, respectively. An opening / closing cylinder (hydraulic cylinder) 23 as a connecting / disconnecting means is penetrated through a guide hole provided in the cylinder guide portion 21b, and the cylinder 23 passes through between the pair of guide rails 22a and 22b and the tube 23a thereof.
The front end of is fixed to the movable holding piece 24.

The movable holding piece 24 includes engagement grooves 24a and 24b (FIG. 2) which engage with the pair of guide rails 22a and 22b, and a recess 24c formed between the engagement grooves 24a and 24b. And a through hole through which the piston rod 23b of the cylinder 23 penetrates is formed at the bottom of the recess 24c. The piston rod 23b of the cylinder 23, which is penetrated by the cylinder guide portion 21b, is penetrated by the through hole of the recess 24c, and then the tip thereof is fixed to the sandwiching portion 21a of the fixed sandwiching piece 21. A mounting flange 23c is formed at the tip of the tube 23a of the cylinder 23, and the flange 23c is fixed to the bottom surface of the recess 24c. That is, the cylinder tube 23a is integrated with the movable gripping piece 24, and the piston rod 23b is integrated with the fixed gripping piece 21. Therefore, the expansion and contraction of the cylinder 23 causes the movable gripping piece 24 to move to the gripping portion 21a of the fixed gripping piece 21. It separates and contacts in a straight line.

Here, there is no positional deviation L as shown in FIG. 11 between the tip of the movable holding piece 24 and the tip of the holding portion 21a of the fixed holding piece 21, that is, in other words, with the tip of the movable holding piece 24. The straight line connecting the tip of the sandwiching portion 21a is the conveying material 20.
It is substantially parallel to the gripping direction of 1 (direction A). Also,
Grooves DR with which the conveying material 201 engages are formed on the surfaces of the movable sandwiching piece 24 and the sandwiching portion 21a that face each other, and the conveying material 2 such as H steel is formed through the groove DR.
01 is held between the holding piece 24 and the holding portion 21a.
The cylinder 23 is driven by a hydraulic drive device (not shown) provided in the main body of the hydraulic excavator.

Next, the operation of gripping the conveying material (here, H steel) 201 by the hydraulic excavator (handling machine) having the gripping device 100 and arranging it along the vertical wall will be described. First, both cylinders 23
To extend the pair of left and right movable holding pieces 24 to the position indicated by P in FIG. 1B, that is, the holding portion 21a of the fixed holding piece 21.
It is located at the position farthest from. In this state, the boom 122 and arm 123 of the hydraulic excavator (see FIG.
0) is operated to direct the gripping device 100 downward so as to face the conveying material 201 placed on the ground and then descend.

After that, the groove DR of the pair of left and right holding portions 21a is formed.
After engaging one end portions of the conveying material 201 with each other, both cylinders 23 are contracted via a hydraulic drive device (not shown). Along with this, the pair of movable pinching pieces 24 integrated with the cylinder tube 23a are connected to the guide rails 22a, 22.
Guided by b, it is linearly driven toward the holding portion 21a side of the fixed holding piece 21, that is, in the direction A in the drawing. Since the movable holding piece 24 is linearly driven in this manner, the straight line connecting the tip of the holding portion 21a and the tip of the movable holding piece 24 is always held in the gripping direction of the conveying material 201 (direction A) regardless of the amount of drive.
Holds a state of being substantially parallel to. That is, there is no displacement between the nipping portion 21a and the tip of the movable nipping piece 24. When the movable gripping piece reaches the conveying material 201, the groove DR thereof is engaged with the other end of the conveying material 201, whereby the conveying material 201 is gripped between the movable gripping piece 21 and the sandwiching portion 21a.

Thereafter, the main body of the hydraulic excavator is moved and the boom 122 and the arm 123 are driven to orient the gripping device 100 in the horizontal direction as shown in FIG.
Similarly to the above, the transport material 201 is horizontally arranged along the vertical wall. At that time, as described above, the holding portion 21a.
Since the tip of the movable holding piece 24 is not displaced, the transport material 201 can be arranged without any trouble. Further, in the present embodiment, since the movable holding piece 24 moves linearly, the lengths of the holding portion 21a of the fixed holding piece 21 and the movable holding piece 24 are smaller than those of the rotating type shown in FIGS. Since it can be shortened, there is an effect that the stability of the entire hydraulic excavator is improved.

Although the cylinder tube 23a is integrated with the movable holding piece 24 and the piston rod 23b is integrated with the fixed holding piece 21, the cylinder tube 23a is integrated with the fixed holding piece 24. The piston rod 23b may be integrated with the movable holding piece 21.

FIG. 3 shows another embodiment. In the above-described embodiment, since the tube 23a of the cylinder 23 protrudes upward in FIG. 1 when the movable holding piece 24 is opened, the cylinder tube 23a may come into contact with a beam or the like at a construction site and be damaged. Therefore, in this embodiment, an example is shown in which a differential rack and pinion mechanism is used to prevent the cylinder from protruding regardless of the position of the movable holding piece.

In FIG. 3, a fixed holding piece 31 constituting a pair of holding mechanisms 30 (only one of which is shown) is fixed to the lower end of the base plate 10 attached to the turntable 2, and the fixed holding piece 31 is fixed to the fixed holding piece 31. The tube 33a of the cylinder 33 is fixed. A pair of pinion gears 41 are coaxially and rotatably supported on the piston rod 33b of the cylinder 33, and the pair of fixed rack gears 42 fixed to the base plate 10 have the pinion gears 41.
And a pair of movable rack gears 43 fixed to the movable holding piece 34, respectively. The movable clamping piece 34 is
Similar to the above, the guide rails 22a and 22b guide the elevation.

In the above structure, when the cylinder 33 contracts, the pinion gear 41 moves to the fixed holding piece 31 side along the fixed rack gear 42 while rotating, and accordingly,
The movable holding piece 34 moves in the same direction via the movable rack gear 43. At this time, since the movable holding piece 34 is moved by both the contraction operation of the piston rod 33a and the rotation operation of the pinion gear 41, the moving amount thereof is larger than that when the tip end of the piston rod 33a is simply connected to the movable holding piece 34. Is doubled. In other words, the stroke amount of the piston rod 33a required to move the movable holding piece 34 by the same amount as that of the embodiment of FIG. 1 is half that of the embodiment of FIG. 1, and the cylinder tube 34a is projected upward or downward. You don't have to. Therefore, the cylinder tube 23a does not come into contact with the beam or the like at the construction site, and its damage is prevented.

Further, FIG. 4 shows a two-stage type cylinder (telescopic cylinder) 50 instead of the differential rack and pinion mechanism.
Shows an example using. Also in this case, the moving amount of the movable holding piece can be increased as compared with the case of using a normal cylinder, and the same effect as the above can be obtained. In addition to this, it is conceivable to move the movable holding piece by using a motor and a ball screw, but in this case, a brake, a reduction gear mechanism, etc. are required, and the structure is complicated, the weight is heavy, and the cost is increased. On the other hand, the method shown in FIGS. 3 and 4 is simple in construction, light in weight, and inexpensive.

In the embodiment described above, the carrier material H
An example of holding the steel 201 in the direction shown in FIG. 12 (b) has been shown, but in order to hold the H steel in the direction shown in FIG. 12 (a),
As shown in FIG. 5A, the holding portion 61a of the fixed holding piece 61 and the movable holding piece 64 may be longer than those described above.
Here, as shown in FIG. 5B, the movable holding piece 64 of the present embodiment has slide plates 64a and 64b fixed to the inner peripheral surface thereof, and these slide plates 64a and 64b. By sliding the guide rails 62a and 62b respectively, the movement of the movable holding piece 63 is guided.

However, the holding portion 61a and the holding piece 64
When the H steel 201 is gripped, when the force in the arrow direction acts on the tip of the movable gripping piece 64 when gripping the H steel 201, the movable gripping piece 6
4 is inclined and the corners of the slide plates 64a and 64b come into contact with the portions of the guide rails 62a and 62b shown by A and B in FIG. Therefore, if the holding work of the H steel 201 having the same size is repeated, a large load is repeatedly applied to the same point of the guide rails 62a and 62b to wear the portion, and the movable holding piece 64 may not be able to move smoothly. .

Therefore, in the embodiment shown in FIGS. 6 (a) to 6 (c),
Slide plates 64a and 64b and guide rail 62
A slide piece 65 is provided between a and 62b to prevent the load from being concentrated on the same point. Figure 6
5A is a view corresponding to the VI portion of FIG. 5A, and the slide plates 64a and 64b are provided with arcuate grooves 64c at two corners (locations corresponding to A and B in FIG. 5). A slide piece 65, which is formed respectively and has an arc surface 65b as shown in FIG. 6B, is engaged with the groove 64c. 66 and 67 are slide plates 64a,
These are bolts and nuts for integrating 64b with the movable holding piece 64.

In the above structure, when the cylinder 63 (FIG. 5) is expanded and contracted, the flat portion 65 of the slide piece 65 is formed.
When a slides on the guide rails 62a and 62b, the movement of the slide plates 64a and 64b, that is, the movable holding piece 64 is guided. According to this, the sandwiching portion 61a
When gripping the H steel 201 between the movable holding piece 64 and the movable holding piece 64, even if a force in the direction of the arrow in FIG. 5A acts on the tip of the movable holding piece 64, portions A and B of the guide rails 62a, 62b. The flat surface portion 65a of the slide piece 65 is in surface contact with each other, and the corner portions of the slide plates 64a and 64b are not pressed. Therefore, even if the H-steel 201 having the same dimensions is repeatedly gripped, a large load is not repeatedly applied to the same point of the guide rails 62a and 62b, wear of the guide rails 62a and 62b is suppressed, and the movable gripping piece is always held. 64 can be moved smoothly. In addition, the circular arc surface 65b of the slide piece 65 is the slide plate 64.
Since it is in contact with the circular arc surfaces of the grooves 64c of a and 64b, it is possible to prevent wear of the corner portions of the movable holding piece 64.

FIG. 7 shows an example in which the length L1 of the movable holding piece 64 'in the load direction is longer than that in FIG. By lengthening L1, the load applied to the portions A and B in FIG. 5A can be reduced, and the wear of the guide rails 62a ′ and 62b ′ can be further reduced in combination with the effect of the slide piece 65. In this embodiment, the guide rails 62a 'and 62b' are extended downward by the length of L1 so that the movement of the movable holding piece 64 'is not hindered. Further, even when a force in the vehicle lateral direction (direction orthogonal to the paper surface of FIG. 7) acts on the movable sandwiching piece 64 ′, local force may act on the guide rails 62a ′ and 62b ′,
In order to suppress this, it is desirable to make the length L2 in the front-rear direction of the moving holding piece 64 'as long as possible.

By the way, when a small conveying material 201 is grasped by a grasping device having a long clamping piece, if the conveying material 201 is grasped in a state of being located at the base of the clamping piece, the conveying material 201 is moved along the wall as shown in FIG. This will hinder the work of arranging. Therefore, in the embodiment of FIG. 7, the stopper 71 is provided inside the fixed holding piece 61 ′ so that the conveying material 201 does not go to the base of the holding piece. The stopper 71 is attached from the outside of the fixed holding piece 61 'via a pin 72, and the fixed holding piece 61' is provided with a plurality of pin holes so that the position in the front-rear direction can be changed. Thus, the stopper position can be changed according to the size of the conveyed conveyance material 201.

In the above, the case where the H steel is gripped as the transport material has been described, but the present invention can be used when gripping a transport material other than the H steel. Further, the construction machine to which the gripping device according to the present invention is attached is not limited to the hydraulic excavator.

[0031]

According to the present invention, the movable gripping piece is driven while the straight line connecting the tip of the fixed gripping piece and the tip of the movable gripping piece is kept substantially parallel to the gripping direction of the conveying material. Therefore, regardless of the size of the conveyed material to be gripped, the tip positions of the two holding pieces are not displaced, and the operation of arranging the conveyed material along the vertical wall can be performed without any trouble. Further, since the length of the fixed and movable sandwiching pieces can be shortened as compared with the conventional example in which the movable sandwiching piece is rotated, there is an effect that the stability of the entire construction machine in which the gripping device is mounted is improved. . Particularly, according to the invention of claim 2, since the separating / connecting means is constituted by the cylinder including the cylinder tube fixed to one of the sandwiching pieces and the piston rod fixed to the other sandwiching piece, the connecting / disconnecting means is extremely small. The movable clamping piece can be driven linearly with a simple structure. Further, according to the invention of claim 3, since the cylinder having the fixed side rack gear, the movable side rack gear, and the pinion gear meshed with these is used, the cylinder stroke amount at the time of driving the movable holding piece can be small, The movable gripping piece can be driven without projecting the cylinder from the gripping device. Further, according to the invention of claim 4, a slide member is interposed between the guide rail for guiding the movement of the movable sandwiching piece and the movable sandwiching piece, and the slide member makes surface contact with the guide rail and the movable sandwiching piece, respectively. With this configuration, even if the length of the sandwiching piece is increased, a local load does not act on the guide rail, wear of the guide rail is suppressed, and the movable sandwiching piece can be always driven smoothly. Furthermore, the invention of claim 5 is provided with a positioning stopper for positioning the conveying material to be gripped with respect to the fixed sandwiching piece, and the position of this stopper is adjusted between the base end portion and the tip end portion of the fixed sandwiching piece. Since it is possible, a particularly small conveying material is not gripped at the base of the sandwiching piece, and the wall attaching work of the conveying material can be performed without any trouble.

[Brief description of drawings]

1A is a front view showing a gripping device according to an embodiment of the present invention, and FIG. 1B is a right side view thereof.

FIG. 2 is a view seen from a line II-II in FIG.

FIG. 3A is a front view of a gripping device according to another embodiment,
(B) is the left side view.

FIG. 4A is a front view of a gripping device according to another embodiment, and FIG. 4B is a left side view thereof.

FIG. 5 shows another embodiment in which the size of the holding piece is lengthened,
(A) is a side view, (b) is the bb line sectional view.

FIG. 6 shows another embodiment in which a slide piece is added,
5A is an enlarged view corresponding to the VI portion in FIG. 5, FIG. 6B is a cross-sectional view taken along the line bb, and FIG. 6C is a perspective view illustrating the shape of the slide piece.

FIG. 7 is a side view showing another embodiment in which a positioning stopper is added.

FIG. 8 is a side view showing a handling machine including a conventional double-acting type gripping device.

FIG. 9 is a front view showing another conventional example of the gripping device.

FIG. 10 is a side view showing a handling machine including a conventional single-acting type gripping device.

FIG. 11 is a diagram illustrating a conventional problem.

FIG. 12 is a diagram showing a working example of a handling machine including a gripping device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 plate 2 turntable 10 base plate 20,30 gripping mechanism 21, 31, 61 fixed gripping piece 21a gripping part 22a, 22b guide rail 23 cylinder 24 movable gripping piece 201 carrier material 100 gripping device

Front page continuation (72) Inventor Hiroshi Tanigawa 650 Kazutachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Engineering Co., Ltd. (72) Inventor Ryuichi Shimazawa 2-6 Otemachi 2-chome, Chiyoda-ku, Tokyo Inside Construction Machinery Co., Ltd. (72) Inventor Kaoru Kiriyama 2-6-2 Otemachi, Chiyoda-ku, Tokyo Inside Nitto Construction Machinery Co., Ltd.

Claims (5)

[Claims] 1. A grip that includes a fixed gripping piece attached to a work attachment of a construction machine, and a movable gripping piece that can be brought into and out of contact with the fixed gripping piece, and grips a conveying material between the both gripping pieces. In the device, the movable holding piece is linearly moved with respect to the fixed holding piece while maintaining a state in which a straight line connecting a tip of the fixed holding piece and a tip of the movable holding piece is substantially parallel to a gripping direction of a conveying material. A gripping device comprising a separation / contact mechanism for separating / contacting. 2. The separating / connecting means is composed of a cylinder including a cylinder tube fixed to one of the sandwiching pieces and a piston rod fixed to the other sandwiching piece. The gripping device according to claim 1. 3. The separation / contact means is integrated with the fixed holding piece, and is fixed to a fixed rack gear extending in the holding direction of the conveying material, and is integrated with the movable holding piece, and is parallel to the fixed rack gear. And a cylinder tube fixed to the fixed holding piece, and a cylinder formed of a piston rod having a pinion gear that meshes with the fixed and movable rack gears. The gripping device according to claim 1. 4. A slide having guide rails for guiding the movement of the movable gripping piece and a contact surface interposed between the guide rail and the movable gripping piece and having surface contact with the guide rail and the movable gripping piece, respectively. The gripping device according to any one of claims 1 to 3, further comprising a member. 5. A positioning stopper for positioning the conveying material to be gripped with respect to the fixed holding piece, and a position adjusting mechanism for adjusting the position of the stopper between the base end portion and the tip end portion of the fixed holding piece. The invention further comprises:
The gripping device according to any one of 4 above.