JPS6232792Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an article gripping device attached to the tip of an arm in a so-called industrial robot.
More specifically, it relates to a gripping device that can handle even if the object to be gripped and the gripping portion of the gripping claw are slightly misaligned, and that can absorb shock when the gripping claw comes into contact with an obstacle, etc. It is something.

For example, an industrial robot moves from a first position to a second position.
It is used in a variety of fields, including transporting parts to different locations. Generally, when transferring an article, a gripping device for grasping the article is usually attached to the tip of an arm of an industrial robot. When gripping an article with the above-mentioned gripping device,
It is necessary to accurately teach the movement of the robot arm in advance so that the gripping section of the gripping device is properly aligned with the article, and there are problems such as when the article is misaligned, it may become difficult to grip it.

The present invention has been made to solve the above-mentioned disadvantages, and preferred embodiments thereof will be described in detail below with reference to the drawings.

The article gripping device 1 shown in FIGS. 1 and 2 is mounted on a rotary base 5 which can be rotatably positioned at the tip of a rotary shaft 3 at the tip of a robot arm on a plane perpendicular to the rotary shaft.
A plurality of them are provided so as to protrude forward in parallel to the rotation axis.

The article gripping device 1 includes a gripping claw base 7 whose front end is formed into a yoke shape, a fluid pressure cylinder 9 provided at the rear end, and a pair of left and right gripping claws 11 whose tips are slidable.
The gripping claw portion 11 has a gripping claw base 7.
The shaft 13 is attached to the gripping claw base 7 in the yoke-shaped groove.
The front end of the piston rod 17, which is driven by the piston 15 of the hydraulic cylinder 9, is also formed in a yoke shape, and is provided with an elongated hole 21 by a shaft pin 19. A link 23 extending in the left-right direction is slidably attached.

In the gripping claw portion 11 illustrated on the left side of FIG. 1, a gripping claw piece 27 in contact with a block 25 (shown in a circular cross section) as an object to be gripped can swing around a shaft body 29. The pair of gripping claw pieces 27 are configured to be able to grip even blocks 25 that have some variation in size and shape, and are implanted near the rear end of the gripping claw portion 11 at a distance shorter than the center distance of the shaft 13. The slide pin 31 is located in the elongated hole 21 of the link 23 described above.
is engaged in.

In the article gripping device 1 shown in FIG. is compressed and fitted, and a ventilation hole 43 is provided in the cylinder lid 39.

In this way, when fluid pressure is introduced to the fluid pressure piping 35, the piston 15 compresses the bullet 41 and retreats, and the piston rod 17 retreats the link 23 and the slide pin 31 as well, so the gripping claws 11 approach each other. Then, the block 25 is grasped.

There is no need to particularly explain that if the fluid pressure is released to atmospheric pressure, the gripping claws 11 will release the block 25 due to the biasing force of the ammunition 41.

The article gripping device 1 illustrated on the right side of FIG.
It is secured to the gripping claw portion 11 with a fastener 45 such as a bolt, so that replacement is easy.

In this example, since the center distance in the left and right direction of the slide pin 31 is set to be larger than the inherent distance of the shaft 13, if the piston 15 is guided from the cylinder cover 39 of the fluid pressure cylinder 9 to the rear pressure chamber 37, the piston 15 will move toward the front of the cylinder. Since the bullet 41 compressed and fitted between the wall surface and the wall surface is compressed and moved forward, the piston rod 19 also advances and the link 23 is also advanced.
The front ends of the block 25 are brought closer together to grip the block 25.

In the example of the article gripping device 1 on the right side of FIG. 1, the vent hole 43 passes through the front wall surface of the fluid pressure cylinder 9 and communicates the front pressure chamber 33 with the groove in the yoke-shaped portion of the gripping jaw base body 7 .

In the apparatus of the embodiment illustrated on the right side of FIG.
The entire gripping claw base 7 is configured to be slidable in the front and rear directions within a cylindrical body 47 fixed to the rotating base 5. That is, a guide groove 49 is provided in the front large diameter portion of the gripping claw base 7, and its rotation with respect to the cylinder 47 is restricted by a guide bolt 51.
7 and the outer periphery of the fluid pressure cylinder 9.
is provided, and this slider 53 is in contact with a part of the front surface of the rotating base 5 at its retreating end. In this state, the slider 53 is also in contact with the front surface of a snap ring 55, which serves as a locking member fixed to the outer periphery of the fluid pressure cylinder 9, to prevent the gripping claw base 7 and the slider 53 from separating.

Furthermore, between the slider 53 and the gripping claw base 7, a coil spring 57 with a weak stored force acts as a first bullet biased to project the gripping claw base 7. An outer coil spring 59 with a weak stored force is compressed and fitted between the cylinder body 47 and the second bullet biased to throw the gripping claw base body 7.

Therefore, when the gripping claw piece 27 of the gripping claw portion 11 is open, the slider 53 is biased by the inner coil spring 57 and its lower end comes into contact with the upper surface of the snap ring 55, as shown in FIG. In this state, the block 25 is seated on the front surface of the rotating base 5 under the force of the outer coil spring 59. Let's introduce fluid pressure into the fluid pressure cylinder 9 to move the piston 15 forward and grip the block 25 with the gripping claws 27. When this happens, for example, if the block 25 is located in front of the illustrated position within the width range of the V groove of the gripping claw piece 27, a force will be exerted to pull out the gripping claw base 7 forward.

In this case, the slider 53 is the inner coil spring 5
7, the outer coil spring 59 is compressed while remaining in contact with the snap spring 55, and the gripping claw base 7 moves forward to grip the block 25.

Conversely, if the block 25 is located at the rear of the illustrated position within the V-groove width range of the gripping claw piece 27 at the time of gripping, a force that pushes the gripping claw base 7 backward as a whole acts, and the slider 53 While seated on the front surface of the rotating base 5, the gripping claw base 7 compresses the inner coil spring 57 and retreats, and the snap spring 55 separates from the rear end surface of the slider 53.

Thus, the article gripping claw device 1 shown on the right side of FIG. 1, which is equipped with the cylinder 47, the slider 53, and the inner and outer coil springs, can automatically grip the object even if the position of the block 25 is slightly shifted in the front-rear direction. The claw base 7 can move back and forth to grip the object.

Figure 2 shows the rotating base 5 at 180 degrees from the state shown in Figure 1.
It shows a perspective view in a state where the left and right sides have been rotated by a degree.

FIG. 3 shows a reference example of the present invention, in which a gear 61 is rotatably or fixedly attached to the side surface of the robot's tip rotating shaft 3, and a gripping claw base 7 is provided at an equal distance from the shaft center. The fluid pressure cylinders 9 are rotated by the gears 61, and the plurality of gripping claw bases 7 on the rotating base 5 are rotated as shown by the arrow 63, revolved as shown by the arrow 65, and moved forward and backward by the fluid pressure cylinder 9 as shown by the arrow 67. The structure is such that the original movement is performed. With this configuration, both ends of a long shaft having a stepped portion, for example, can be gripped by the cooperation of the two gripping devices.

In the reference example shown in FIG. 4, both left and right tapered cams 69 enter the center of a cam follower roll 71 provided behind the gripping claw 11 as means for opening and closing the gripping claw 11 and the grasping claw piece 27. A tension spring 73 is provided in the middle to release the gripping claw piece 27 from the block when the cam 69 retreats.

As can be understood from the above description of the embodiments, the essential gist of the present invention is as stated in the claims for utility model registration, and as is clear from the description, in the present invention, the tip of the arm is A cylindrical slider is slidably fitted and supported in the cylindrical body fixed to the base, and the slider has a gripping claw base body equipped with gripping claw pieces that can freely grip an object to be gripped. Fitted and supported for reciprocating movement. A first bullet that urges the gripping claw base in a direction to protrude from the cylinder is loaded between the gripping claw base and the slider. A locking member is provided for locking the two to prevent them from coming apart. Furthermore, a second bullet which urges the gripping claw base to sink into the cylinder is loaded between the cylinder and the slider. The bombs are installed in parallel.

Therefore, when the gripping claw pieces try to grip the object to be gripped, even if the object to be gripped and the gripping portion of the gripping claw pieces are slightly misaligned, the first ammunition Alternatively, by moving the gripping claw base body in an appropriate direction against the second bullet, the object to be gripped and the gripping portion of the gripping claw piece are aligned, and the object to be gripped can be accurately gripped. . Further, for example, when the tip of the gripping claw piece or the gripped object comes into contact with an obstacle, the gripping claw base moves against the first and second bullets. It can absorb shock.

Further, as described above, the slider is fitted and supported on the cylinder fixed to the base, and the gripping claw base is fitted and supported on the slider, so that the gripping claw base slides on the cylinder. When moving, stable sliding occurs and no rocking or the like occurs. Further, the configuration in which the first ammunition machine and the second ammunition machine are provided in parallel reduces the length in the axial direction, and is desirable as a configuration to be provided at the tip of an arm of an industrial robot. Since the first and second bullets do not interfere with each other, as if one is contracted and the other is extended, the settings of the bullets are easy.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the device according to the present invention, Fig. 2 is a perspective view of the same as above, Fig. 3 is an explanatory view of a reference example, and Fig. 4 is an explanatory view of the grip-release operation portion of another reference example. . Explanation of symbols representing main parts of the drawings, 5...Rotating base, 7...Gripping claw base, 11...Gripping claw part,
27...Gripping claw piece, 53...Slider, 57...Inner coil spring, 59...Outer coil spring.

Claims (1)

[Scope of utility model registration request] A cylindrical body 47 is fixed to a base provided at the tip of the arm, a cylindrical slider 53 is slidably fitted into the cylindrical body 47, and the slider 53 is fitted and supported. A gripping claw base 7 is provided to be able to freely reciprocate in the axial direction, and a gripping claw piece 27 that can freely grip an object to be gripped is attached to the gripping claw base 7, and the gripping claw base 7 protrudes from the cylindrical body 47. A first elastic force biased in the direction is provided between the gripping claw base 7 and the slider 53, and a locking member for locking the gripping claw base 7 and the slider 53 is provided. , a second bullet which urges the gripping claw base body 7 in a direction to sink into the cylinder 47 is installed between the slider 53 and the cylinder 47, and a first bullet. An article gripping device comprising a machine and a second bullet machine arranged in parallel.