JPS60104687A - Gripper - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a gripping device used in industrial robots and the like.

[Technical background of the invention and its problems]

In recent years, many industrial robots with functions similar to the motor functions of human upper limbs have been used in fields such as the manufacturing industry. A gripping device corresponding to a hand is provided.

This gripping device is required to be able to perform not only the simple work of gripping and transporting an object to be gripped, but also sophisticated work such as assembly work.

Conventionally, there is a type of gripping device that utilizes the reciprocating motion of a drive device such as a cylinder that reciprocates in the opening and closing directions to reciprocate a pair of gripping bodies.

FIG. 1 shows a conventional gripping device of this type. 1 in the diagram
, 1 are a pair of gripping bodies, and these gripping bodies 1, 1 are attached to the frame 2.
It is supported so as to be movable in a straight line on a guide rail 3. A drive rod 4 is provided at the center of the frame 3 in a direction perpendicular to the guide rails 3, 3, and the drive rod 4 is reciprocated by a drive device (not shown), such as an air cylinder. Links 5, 5 are connected via pins 6 between the drive rod 4 and the pair of gripping bodies 1, 1. Note that the frame 2 is attached to, for example, an arm of a robot (not shown). When the drive rod 4 moves in one direction, the gripping bodies 1, 1 move in the closing direction along the guide rails 3, 3 via the links 5.5.

While the gripping bodies 1, 1 move to the closed limit, the object to be gripped 70
Grip by touching both sides. The entire gripping device is then moved to another location by movement of the robot's arm. Therefore, the drive rod 4 moves in the opposite direction and links 5,5
The grips 1, 1 are moved along the guide rails 3, 3 in the opening direction. The gripping bodies 1, 1 move to a certain opening limit position, separate from the object to be gripped 7, and release the grip.

However, the conventional gripping device, like the above-mentioned operation,
When the gripping body 1.1 moves in the opening direction, it operates so that its opening limit is always at a constant position, and the gripping bodies 1, 1 are temporarily moved at the opening position with a small interval on the way to the opening limit. No consideration has been given to stopping it. For this reason, the gripping body 1
It is not possible to work in places where the movement distance in the opening direction of °1 is small and restricted. For example, a part 8 having a recess 8&
Let's consider an assembly operation in which the object to be grasped 7 is inserted into. After inserting the object 7 gripped by the grippers 1, 1 into the component 8,
When the gripping bodies 1,1 move away from the object to be gripped 7 in the opening direction, the inner width of the recess 8a of the component 8 is smaller than the opening limit of the gripping body 1.1. It collides with the side wall and becomes unable to move. Therefore, the conventional gripping device cannot perform assembly work in such a narrow space, and its use in industrial robots is limited.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and is a gripping device that can perform assembly work in a narrow place where the moving distance in the opening direction of the gripping body is limited, and has expanded applications when used in industrial robots. It provides:

[Summary of the invention]

In the gripping device of the present invention, a pawl is pivotally connected to a pair of gripping bodies that are opened and closed by a drive device, and a ratchet pawl is pivotally attached to the pawls, and the ratchet pawls contact the gripping body of the ratchet pawl. Ratchet teeth that allow movement in the closing direction and prevent movement in the opening direction are provided in the grip body opening/closing direction, and furthermore, a position where the two-check pawl contacts the ratchet teeth and a position where the ratchet pawl separates from the ratchet teeth are provided. A locking mechanism is provided for positioning the claws relative to the gripping body. When the gripping body that grips the object to be gripped is moved in the opening direction, the movement of the gripping body is restricted to a small distance by the engagement of the ratchet pawl and the ratchet teeth C. Further, the restraint of the grip body is released by moving the grip body to the closed limit, and the above-mentioned operation is made possible again by moving the grip body to the open limit.

[Embodiments of the invention]

An embodiment of the present invention illustrated in the drawings will be described below.

2 to 8 show an embodiment of the gripping device of the present invention.

In the figure, a pair of gripping plates 1, 1, frame 2), guide rails 3, 3, drive port, door 4, and links 5, 5 are the same as in FIG. 1, so their explanation will be omitted. ]: On the lower surface of the guide rail 3 located on the side, a large number of ratchet teeth 9°9 are formed extending in the longitudinal direction except for the central part.
The ratchet teeth 9, 9 are oriented such that ratchet pawls 13, 13, which will be described later, collide with each other when the grips 1, 1 move in the opening direction. In addition, a pair of gripping plates 1
, 1 have claws 10.10 facing each other and pivotally attached to the bins 11.11.

A ratchet pawl 13.13 that engages in meshing contact with the ratchet teeth 9 of the guide rail 3 is attached to a pin 14. It is pivoted by 14. These ratchet pawls 13.13 are operated by compressed coil springs 15, 15 provided on the pawls 10.10.
Rotational force is applied in the direction of meshing with ratchet tooth 9.
, 9 is maintained. In addition, nail 10.10
Stopper surfaces 10a, 10a for regulating the rotation of the ratchet pawls 13.degree. Further, as shown in FIG. 8, a hole 16.16 is formed in the pawl 10.10, and a compression type coil spring 18 held by the spring retaining screw 17 and a coil spring 16 are formed in the hole 16.16. A claw 19 is provided which is pressed toward the side surface of the grip 1 by the handle 18 . Positioning holes 20.20 and 21.21, in which the ball 19 is pressed and engaged by the coil spring 18, are formed on the side surface of the gripping body 1.1 facing the claw 10.10. One of the positioning holes 2 (1, 20 is set at a position where the pawl 10.10 is positioned and fixed relative to the grip body 1.degree. 1 when the ratchet pawl 13.13 is engaged with the 2-chatch tooth 9.9, The other positioning hole 21.21 is set at a position where the pawl 10.10 is positioned and fixed relative to the gripping body 1, 1 when the ratchet pawl 13.13 is disengaged from the ratchet teeth 9.9. Bushings 22, 22 are provided on the upper parts of both the guide rails 3 which have been formed with the guide rails 3.

The operation of the gripping device 6 configured as described above will be described with respect to a case where a silk making machine is used to grip an object 7 to be gripped and insert it into a component 8. First, when gripping the object to be gripped 7, as shown in FIG. It is moved along the rails 3, 3 in the closing direction. The gripping bodies 1, 1 move from both ends of the guide rail 3.degree. 3 toward the center so as to approach each other, and grip an object 7 placed on a stand (not shown) from both sides. Nail 1
0.10 and 2-check claws 13.13 are grippers 1,1
and move all at once. In this case, the pawl 10.10 and the ratchet pawl 13.13 are connected to the ratchet teeth 9°9 of the guide rail 3.
The ball 19.19 provided in the hole 16.16 of the pawl 10.10 is in a position to engage with the coil spring 1B, 1B.
is pressed by the positioning holes 2θ, 2 of one of the gripping bodies 1, 1.
0 to position the pawl 10.10 relative to the gripping bodies 1,1. The ratchet pawl 13.13 is pushed by a coil spring 15.15 and moves while sequentially contacting each ratchet +-@9.9 arranged in the longitudinal direction of the guide rail 2. In addition, since the ratchet teeth 9, 9 have their upright surfaces located on the gripper closing direction side as shown in the figure, the ratchet claws IJ
, 7.9 does not inhibit movement in the closing direction.

Next, by driving the arm of the robot equipped with the frame 2, the entire gripping device that grips the object 7 is moved upward to another location, for example, and the object 7 is placed on the part 8 placed at that location. insert.

In this case, as shown in FIG. 3, a recess 8a is formed in the component 8, and the tip of the gripper 1.1 is located inside this four part 8a.

Next, the gripping bodies 1, 1 are separated from the cedar gripping object 7 to release the grip. When the drive rod 4 is moved in the direction of the arrow shown in FIG. 3, the grips 1, 1 start moving in the opening direction via the links 5, 5. Nail 10.
10 and the ratchet pawls 13.13 also move together with the gripping bodies 1, 1 in the opening direction. Here, the ratchet tooth 9
, 9, the ratchet pawls 13° 13, which are in contact with the ratchet teeth 9, 9, move from the distal end side position of the inclined surfaces of the ratchet teeth 9, 9 shown in FIG. As shown in , the ratchet tooth 9 collides with the upright surface of the adjacent ratchet tooth 9 and is prevented from moving.

The moving distance of the ratchet pawls 13, 13 at this time is small, within one pitch of the ratchet teeth 9. At the same time, as shown in FIG. 3, the gripping bodies 1, 1 move in the opening direction by a small distance corresponding to the movement distance of the ratchet pawls 13 and 13, and move away from both sides of the gripped object 7. .

Therefore, the gripping bodies 1, 1 release their grip on the object 7 to be gripped. In this case, since the moving distance of the grippers 1, 1 in the opening direction is small, they do not collide with the wall of the recess 8a of the component 8. On the other hand, when the ratchet pawl 13.13 collides with the upright surface of the two ratchet teeth 9, 9, when a force is applied to the gripping bodies 1, 1 by the drive rod 4 in the opening direction, the ratchet pawl 13.13 rotates about the bin 14.14 in the direction of the arrow. However, the ratchet pawl 13.13 is slightly rotated so that the pawl 10°1θ has a stopper surface 10th,
10a and is prevented from rotating. In the end, the gripping body 1,
1 is held between the bottle 11.11 and the ratchet pawl 13.13 via the pawl 10.10 and the ratchet pawl 13.13, and the force that tends to open the gripping body 1.1 in the opening direction is No movement will take place. Unfortunately, the gripping bodies 1, 1 only move by the above-mentioned small distance in the opening direction,
The grasping of the object to be grasped 7 can be released, and collision with the wall of the recess 8a of the component 8 can be prevented.

Thereafter, the entire gripping device is returned to its original position by the arm, and the assembling operation is repeated in the same manner as described above.

Therefore, when gripping an object 7 of a different size from that described above, the following operations are performed in preparation. As shown in FIG. 4, the gripping bodies 1, 1 are moved from the above-mentioned open state to the closing direction by the operation of the driving rod 4. Then, the claws 10 +' 10 move together with the gripping bodies 1, 1. The respective ends 1111 in the closing direction contact each other, and as the grippers 1,1 move, the claws 10.10 rotate in the direction of the arrow about the bottle 11.11.

The above-mentioned part provided on the claw 10.10 with this fL -Le 19.1
9 comes off from one positioning hole 20, 20 of the gripping bodies 1, 1, and the other positioning hole 2.

21 and is pushed and engaged by the coil spring 18. The position of pawl 10.10 at this time is the closed limit position, and pawl 1
0.10 stops rotating due to engagement between the ball 19 and the positioning hole 21.21, and is positioned and fixed relative to the gripping bodies 1,1.

Also, the ratchet pawls 13, 13 move together with the pawls 10, 10, and reach a position away from the ratchet teeth 9, 9 of the guide rail 2. This screw, ratchet claw 13.13
The restraint on the gripping body 1.1 due to the meshing of the ratchet teeth 9, 9 is released, and the gripping bodies 1.1 are in a state where they can freely move in the opening direction.

Next, as shown in FIG. 5, the gripping body 1,
1 in the opening direction until it approaches the opening limit, the claw 10.
10 is a pusher 22 provided at both ends of the guide rail 3.
．． 22, and while the grippers 1 and 1 reach their opening limits, the claws 10, 10 are pushed back by the pushers 22, 22 in the opposite direction from the closing limit, and the bottle 1 is closed.

It rotates about 11 in the direction of the arrow shown in the figure. This is no good,
The ratchet pawl 13.13, which was in a position where the ratchet teeth 9,9 were also separated, moves together with the pawl 10.10 and comes into contact with the ratchet teeth 9,9 again. Therefore, the operation of moving the gripping body 1 in the closing direction and gripping the object 7 to be gripped becomes t+J.

In addition, in the embodiment described above, the gripping bodies 1, which move to open and close mutually,
1 is provided with pawls 10.10 and ratchet pawls 13.13, respectively. However, one gripping body 1 is movable and the other gripping body 1 is fixed, and the pawls 10 are provided only on this movable gripping body 1. A ratchet 1 and pawl 13 may also be provided.

Further, the present invention is not limited to the standing work of the above-described embodiment, but can be widely implemented when assembling work is performed under conditions where movement of the gripping body in the opening direction is restricted.

〔Effect of the invention〕

As explained above, in the gripping device of the present invention, the moving distance of the gripping body when releasing the grip on the object to be gripped is small, so that assembly work can be performed under conditions where the movement of the gripping body in the opening direction is restricted. This makes it possible to expand the range of applications when used in industrial robots.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of a conventional gripping device, Figs. 2 to 8 show an embodiment of the present invention, and Fig. 2 does not show the gripping state of the object to be gripped. 3 is a front view of the gripping device showing the state in which gripping of the object to be gripped is released, FIG. 4 is a front view of the gripping device showing the state in which the gripping body has been moved to the closed limit, and FIG. A front view of the gripping device showing a state in which the gripping body is moved to the opening limit 1, Figures 6 and 7 are front views showing an enlarged view of the key pawl, ratchet pawl, and ratchet teeth, and Figure 8 is a front view showing the gripping device with the pawl moved to the opening limit 1. FIG. 7 is a sectional view taken along the line XX in FIG. 7, showing an enlarged view of the locking mechanism for positioning and fixing the body. DESCRIPTION OF SYMBOLS 1... Gripping body, 2... Frame, 3... Guide rail, 4... Driving rod, 7... Grasped object, 8...
Parts, 9... Ratchet teeth, 10... Pawls, 13...
Ratchet pawl, 15...Coil spring, 1B...Coil spring, 19...Ball, 20.21...Positioning hole. 14+j agents Patent attorney Takehiko Suzue Figure 5 Figure 4 Figure 6 Figure 7

Claims (1)

[Claims] A pair of gripping bodies to be moved, a pawl pivotally connected to the movable gripping body, a ratchet pawl pivotally connected to the pawl, and a ratchet pawl that is moved in the opening/closing direction of the gripping body and the ratchet pawl is Ratchet teeth that come into contact with each other to allow the grip to move in the closing direction and prevent it from moving in the opening direction, and the position and front T where the ratchet pawl contacts the ratchet teeth.
a locking mechanism for positioning and fixing the ratchet pawl relative to the gripping body at a position where the ratchet pawl is separated from the ratchet yl'teeth; A grip characterized by positioning and fixing a pawl at a position where it contacts the ratchet teeth, and positioning and fixing at a position where the ratchet pawl separates from the ratchet teeth when the grip body is moved to a closing limit. Device.