JP3482530B2 - Chuck - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck used as a gripping tool for an assembly machine for supplying, discharging, and positioning assembly parts, or a hand tool for a robot.

[0002]

2. Description of the Related Art This type of chuck has a structure in which fingers supported by spindles are opposed to each other on the tip side of a cylindrical body, and these are opened and closed by a drive mechanism driven by air pressure or the like. Has become. Further, it is important that the fingers have no play in the opening / closing direction (horizontal direction) and in the direction perpendicular to this (the axial direction of the support shaft ... longitudinal direction) in order to maintain high repetitive position accuracy of work. Is.

Of the backlash in the left-right direction, since the movement of the fingers in the opening / closing direction is restricted by the drive mechanism, the drive mechanism is made to have a high rigidity structure and the force transmission path is accumulated with the working tolerance and the allowable value. Although it has been solved by making it difficult to structure, in the axial direction of the support shaft, the members (rollers, spacers, guides, etc.) supported by the support shaft, including the fingers, simply move in the axial direction of the support shaft. Only polymerized, so far, little has been done to eliminate backlash in the front-back direction.

Moreover, since these members are not tightly joined because it is necessary to reduce mutual movement between the members, even if the processing and assembling of the members are carried out with high precision, it is inevitable that the 2/1
It was impossible to avoid backlash in the front-back direction of about 00 to 5/100 mm. This backlash appears as a position error with respect to the target position of the moved work, particularly when the body is rotated about the axis (up and down direction) of the body for positioning.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a chuck in which fingers have no play in the supporting shaft direction.

[0006]

[PROBLEMS TO BE SOLVED BY THE INVENTION] The present invention relates to a chuck in which fingers are attached so as to face a tip portion of a body accommodating a drive mechanism. The front end side of the body is configured as a fork portion including a front wall and a rear wall that are arranged at a distance. In the space between the front wall and the rear wall of the fork part, a support shaft is mounted over both walls, and the fingers are supported thereby. A biasing body that acts in the axial direction of the support shaft is provided. The urging body constantly urges the fingers to one side of the both walls.

When the finger moves with the inner surface of the front wall or the rear wall of the fork as a guide surface, a sliding surface with at least the finger side as a smooth surface is provided between the finger and the guide surface and between the finger and the urging body. A face plate may be interposed. Further, the smooth surface plate may have rigidity so as not to be deformed by the bias of the biasing body, and the fingers may be biased in the axial direction of the support shaft through the smooth surface plate.

[0008]

The urging body always pushes the finger against one wall side to absorb the play in the front-back direction of the chuck. The smooth plate smoothes the opening / closing movement of the fingers even when the fingers are constantly biased in the axial direction of the support shaft. Further, the rigid smooth plate further disperses the urging force of the urging body in a wide range to make the urging of the fingers uniform.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The figures relate to a single-acting parallel opening / closing chuck.
The chuck generally comprises a body 1, a double piston 4 consisting of an inner piston 2 and an outer piston 3, an action lever 5 and slide fingers 6 (a, b). In the body 1, an upper cylinder portion 7 and a lower fork portion 8 are integrally formed, and the fork portion 8 includes a front wall 9 and a rear wall 10.
And a space 11 is formed between both walls. The double piston 4 is attached to the cylinder portion 7 of the body 1, and the cylinder side air chamber 12 is provided between the cylinder portion 7 and the inner piston 2.
Is provided with a port P1, and the piston side air chamber 13 is provided with a port P2 between the inner piston 2 and the outer piston 3. The port P2 is in this case always open to the atmosphere. Further, between the inner piston 2 and the outer piston 3, a clamp spring 1 for single action is provided.
4 is installed. The clamp spring 14 drives the double piston 4 by its elastic force to move the slide finger 6
There is sufficient elasticity between a and 6b to hold an object (work), and it is mounted so as to always be in a preloaded state.

The action lever 5 is a member that is rotatably supported by a support shaft 30 which will be described later, and has an outer receiving portion 15 and an inner receiving portion 16 on both sides, and an engaging portion 17 formed so as to project between them. It has a triangular shape and has two pieces.

Slide fingers 6 (a, b) (FIG. 3)
The left and right parts have the same structure, and the upper slide part 18 (a, b) and the lower claw part 19 (a, b) are integrally formed. The slide portion 18 includes a front regulation plate 20 (a, b) and a rear regulation plate 21 (a, b) that are parallel to each other in the front and rear. A rail portion 22 (a, b) having a width dimension (length in the front-rear direction) corresponding to the wall thickness of the regulation plates 20, 21 is formed on the lower portion of one side of the regulation plates 20, 21. Therefore, when the slide fingers 6a and 6b are opposed to each other as shown in FIG.
8 (a, b) are superposed and assembled so as to guide each other (FIG. 1). In addition, the regulation plate 2 of the slide portion 18
0 and 21 have long holes 23 and 24 and an engagement pin 25 (FIG. 2).
Are provided respectively.

These parts are assembled as follows. The double piston 4 is attached to the cylinder portion 7 from below the body 1. The action levers 5, 5 are provided between the front and rear regulation plates 20, 21 where the slide fingers 6 (a, b) are superposed, and the engaging portions 17, 17 are individually engaged with the engagement pins of the slide fingers 6 (a, b). 25 and engage. The front rollers 26 and 27 and the rear rollers 28 and 29 are attached to the elongated holes 23 and 24 of the front and rear regulation plates 20 and 21 in the slide portion 18 in the overlapping state.

The entire slide fingers 6 (a, b) assembled in this manner are inserted into the fork portion 8 of the body 1 from below, and a support shaft 30 having a stopper at one end is attached to the front wall 9 of the fork portion 8. The front roller 26, the action lever 5, and the rear roller 28 are penetrated from the front sleeve 31 and the rear sleeve 32 mounted on the rear wall 10 is penetrated, and the E ring 3 is attached to a portion protruding to the rear surface of the rear wall 10.
Attach 3 and mount the shaft. The other support shaft 30, the front roller 27, and the rear roller 29 are also mounted in the same manner.

At this time, as shown in FIG. 4, between the inner surface of the front wall 9 and the rear wall 10 and the slide finger 6 (a, b), that is, the front surface of the front regulating plate 21b of the slide finger 6b and the slide finger 6b. The smooth plates 34, 34 are interposed between the rear regulation plate 21b and the rear regulation plate 21b. Smooth plate 34
Is formed of a rigid thin graphite-containing polyester plate, Teflon plate, or thin stainless plate, and has a hole through which the support shaft 30 passes. Further, the rear sleeve 32 has a front portion formed with a step with a small diameter, and a coil spring 35 as an urging body is attached to the small diameter portion in a preloaded state.

Therefore, the slide fingers 6 (a, a supported by the support shaft 30 in the gap 11 of the fork portion 8).
In b), a smooth surface plate 34 on the rear wall side is interposed, and a coil spring 35 constantly urges forward. As a result, unnecessary play between the members superposed on the support shaft 30 is eliminated. In this case, the urging force of the coil spring 35 acts in the axial direction of the support shaft 30 supporting the slide fingers 6 (a, b) and the action lever 5, so that the members are twisted between the support shaft 30 and the support shaft 30. Is less likely to occur.

Even if the slide fingers 6 (a, b) and the action lever 5 are constantly urged in one direction (forward) by the coil spring 35, the smooth surface plate 34 slides at least on the finger side (inner surface). Since it is a surface, there is no hindrance to the movement of the slide fingers 6 (a, b). Further, the pressing force of the coil spring 35 is applied to the slide finger 6 by the smooth surface plate 34.
It acts uniformly over a wide area with respect to (a, b), and twisting due to uneven distribution of pressure hardly occurs.

By assembling in this way, the push-out side end of the inner piston 2 of the double piston 4 contacts the inner receiving portions 16, 16 of the action levers 5, 5. Therefore, when the driving force is supplied from the port P1 to the cylinder side air chamber 12, the inner piston 2 is moved downward (pushing side), and the inner receiving portion 16 of the action lever 5 is pushed. As a result, the action lever 5 is pivoted outward about the support shaft 30, and the slide fingers 6 (a, b) are opened in parallel to the moving direction of the inner piston 2 via the engaging pin 25. Be done. At the same time, the action lever 5 is pivoted outward so that the outer receiving portion 1
Since 5 pushes the outer piston 3 upward, the outer piston 3 moves upward (in the retracting direction) and the clamp spring 14 arranged in the piston side air chamber 13 is compressed.

When the port P1 is released to the atmosphere, the single-acting clamp spring 14 expands and, contrary to the above, the inner piston 2 is pulled in, and the outer piston 3 is pushed out to the outside of the action lever 5. The receiving portion 15 is pushed. Then, the slide fingers 6 (a, b) are closed, and the target component is held between the fingers. The gripped state is maintained by the elastic force exerted by the single-acting clamp spring 14. That is, the double piston 2, the action lever 5,
5 is a slide finger 6 (a,
It is the drive mechanism of b) and is housed in the body 1.

As described above, the body 1 is caused by the anti-reciprocal movement of the inner piston 2 and the outer piston 3 in the double piston 4 (the movement in which the other always moves in the opposite direction with respect to one)
Slide finger 6 mounted on the fork part 8 of the
(A, b) opens and closes in parallel to the left and right. This opening / closing movement is reliable because it is caused by the above-mentioned anti-reverse movement of the double piston 4, and the backlash in the left / right direction (opening / closing direction) of the slide fingers 6 (a, b) is extremely small. Further, since the slide fingers 6 (a, b) are constantly urged in the support shaft direction by the spring 35, these play in the front-back direction (axial direction of the support shaft 30) is almost eliminated. This machine
Noh is mounted on the front and rear walls 9 and 10 of the fork part 8
The slide fingers 6 (a,
b) Inclination of the clamping surface (when the clamping surfaces on both sides are parallel when closed)
It does not occur, and it has a function of absorbing one-sided contact with the transported product.
Conveyed goods with slide fingers 6 (a, b) sandwiched
The (workpiece) rotates around the one-sided contact point during conveyance and is conveyed.
Dangers such as the feeding posture collapsed or falling
Can be wiped off. Slide film for transported goods
One-sided contact of the ngers 6 (a, b) is a common factor in processing and assembly.
Inevitable due to differences etc., but slide finger 6
An urging body 35 for urging (a, b) in the supporting axis direction is provided.
Can be mitigated by

The above is one embodiment. The present invention is not limited to the illustrated specific configuration. For example, the slide fingers 6 (a, b) are not limited to the slide type that opens and closes in parallel, but may be those that open and close by rotating around the support shaft 30, and the biasing body is not limited to the coil spring 35. An elastic body such as rubber may be used, or the E ring 33 itself for fixing the support shaft 30 may be configured as a spring body such as a disc spring. However, in the case of a coil spring, there is little change in load due to expansion and contraction of the spring, and a stable biasing force can be expected. Further, even if the smooth surface plate 34 has a relatively low rigidity such as a sheet, the slide fingers 6 (a, b)
There is a function to smooth the movement of.

[0021]

EFFECTS OF THE INVENTION With respect to the fingers, play in the supporting shaft direction (front-back direction) for supporting the fingers is eliminated, and the accuracy of repeated position of the work using this chuck is improved. Since the urging force of the urging body acts in the axial direction of the support shaft, twisting due to the urging does not occur, assembly is easy, and the opening / closing characteristics of the fingers are less likely to vary.

[Brief description of drawings]

FIG. 1 is an exploded perspective view.

FIG. 2 is a vertical sectional view.

FIG. 3 is a perspective view of a main part.

4 is a cross-sectional view (partial) taken along the line AA in FIG.

FIG. 5 is a side view.

[Explanation of symbols]

1 Body 4 Double Piston 5 Action Lever 6 Slide Finger 8 Fork 9 Front Wall 10 Rear Wall 11 Space 30 Spindle 34 Smooth Surface Plate 35 Spring (Biasing Body)

Claims (3)

(57) [Claims] 1. A drive mechanism housed in a body
Rotate the lever and use the action lever to tip the body.
It is a chuck that drives a finger that is attached to face the front part of the body, and the tip side of the body is composed of a fork part consisting of a front wall and a rear wall that are spaced apart from each other. support shaft is axially call over both walls, the on support shaft
The action lever of can be rotated, and the fingers
It is supported so that it can slide to the left and right , and on the spindle.
Fingers are attached to one side of both walls by the attached biasing body.
Chucks, characterized in that the normally are biased. 2. The chuck according to claim 1, wherein the fingers move with the inner surface of the front wall or the rear wall of the fork portion as a guide surface, and between the finger and the guide surface and between the finger and the urging body. A chuck characterized in that a smooth surface plate having a smooth surface on at least the finger side is interposed therebetween. 3. The smooth surface plate has rigidity such that it is not deformed by the biasing force of the biasing body, and the fingers are biased in the axial direction of the support shaft through the smooth surface plate. Item 3. The chuck according to Item 2.