JP3060893B2 - 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 for supporting an axis of a workpiece by a center and transmitting rotation by gripping an outer peripheral surface of the workpiece.

[0002]

2. Description of the Related Art Conventionally, when a workpiece is gripped on the basis of a center, both centers of both ends of the workpiece are supported by a center on a chuck side and a center on a tail stock side, and a vignetting attached to the workpiece. The rotation of the chuck is transmitted to the workpiece by engaging the chuck with the workpiece.

[0003]

According to the above-mentioned gripping method, since the burrs are attached to and removed from the workpiece, it takes a lot of trouble and the operating rate of the processing machine is significantly reduced.

[0004] In addition, the use of knurls makes it impossible to automatically mount and remove a workpiece by a robot.

[0005] Further, when the mounting of the burrs is incomplete, the rotation transmission becomes poor due to the slip and the tool such as a cutting tool is damaged.

SUMMARY OF THE INVENTION It is an object of the present invention to transmit rotation to a workpiece gripped on the basis of a center without using burrs.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a rotating body provided to rotate together with a spindle, and a tip end protruding forward from an axis of the rotating body. A center, a plurality of cylinder chambers provided at equally-spaced peripheral portions in the rotating body, and each cylinder chamber is restrained from rotating by appropriate means, and slides forward and backward by fluid pressure supplied from a passage. The piston provided in the above, is inserted in a through hole communicating with the front surface of the rotating body and the cylinder chamber so as to freely rotate at a fixed position, and is rotatably fitted to the outside of a piston rod connected to the piston. A rotating body, a conversion device provided between a contact surface of the rotating body and the piston rod to convert the forward / backward movement of the piston rod into a rotating movement of the rotating body, and each of the rotating bodies Employing a chuck comprising a clamping claw provided on the projecting end facing forward.

Also, a rotating body provided so as to rotate together with the spindle, a center provided with a front end protruding forward from the axis of the rotating body, and a plurality of cylinders provided at circumferentially equal intervals in the rotating body. A piston provided in each cylinder chamber so as not to rotate by appropriate means so as not to rotate; a passage provided to apply a fluid pressure to at least a rear side of the piston in the cylinder chamber; A rotating body which is inserted into a through hole communicating with the front surface of the body and the cylinder chamber so as to freely rotate at a fixed position, and which is rotatably fitted outside a piston rod continuous with the piston; A conversion device provided between the contact surface with the piston rod to convert the advancing and retreating motion of the piston rod into a rotating motion of the rotating body; A retraction restoring force, employing a chuck comprising a clamping claw provided on the projecting end facing the front of the each time the moving object.

Further, a center provided on the stationary spindle and a center of the center are movably screwed to the outside of the front end of the center, and the center of the center is fixed to the outside of the stationary spindle via appropriate engaging means.
A rotating body provided so as to rotate together with a rotating spindle , a plurality of cylinder chambers provided at equally spaced positions in a peripheral portion of the rotating body, and restraint such that each cylinder chamber is not rotated by appropriate means. And a piston provided to slide forward and backward by the fluid pressure supplied from the passage,
A rotating body that is inserted into the through hole communicating with the front surface of the rotating body and the cylinder chamber so as to freely rotate at a fixed position, and that is rotatably fitted to the outside of a piston rod that is connected to the piston; A conversion device provided on a contact surface between the rotating body and the piston rod so as to convert the forward / backward movement of the piston rod into a rotating movement of the rotating body; and a clamp provided on a forwardly projecting end of each of the rotating bodies. A chuck composed of a claw is used.

A center provided on the stationary spindle;
While screwing movably outside the tip of this center,
Pivoting outside the stationary spindle via suitable engagement means
A rotating body provided so as to rotate together with the rotating spindle , a plurality of cylinder chambers provided at circumferentially equal intervals in the rotating body, and each cylinder chamber is restrained from rotating by appropriate means. The piston provided, a passage provided so as to apply a fluid pressure to at least the rear side of the piston in the cylinder chamber, and the through hole communicating the front surface of the rotating body and the cylinder chamber freely rotates at a fixed position. A rotating body fitted and rotatably fitted to the outside of a piston rod connected to the piston, and moving the piston rod forward and backward between the contact surface of the rotating body and the piston rod by rotating the rotating body. A conversion device provided to convert the motion into a dynamic motion, a return force applied to the piston rod by an appropriate means, and a clamp claw provided at a forwardly projecting end of each of the rotating bodies. To adopt a chuck made.

Further, the above-mentioned clamp claw is constituted by a meshing hole and an arc-shaped plate or a disk whose distance from the hole changes gradually, and is fitted with a meshing projecting shaft at the projecting end of the rotating body and the hole. The chuck according to any one of claims 1 to 4, wherein the clamping claws are attached by screws screwed into the protruding shaft.

[0012]

With the above construction, when the fluid is pressed into the rear side of the piston in the cylinder chamber from the passage and the piston is advanced, the rotating body is rotated by the sliding motion of the piston rod which advances together and the conversion device. . Then, the direction in which the clamp claws open (the distance between the clamp claws increases)
To rotate.

After the workpiece is supplied by engaging the end surface axis with the center, the fluid is press-fitted into the front and rear of the piston in the cylinder chamber from the passage. Then, the piston rod retreats together with the piston, so that the rotating body is rotated by the sliding motion of the piston rod and the conversion device, the workpiece is clamped by the crank pawl that rotates in the closing direction, and the rotation rotates together with the spindle. The rotation of the body is transmitted to the workpiece.

Even if the press-fitting of the fluid is interrupted during processing (during clamping) due to some influence, the piston is pushed back together with the piston rod by the restoring force applied to the piston rod (retreating direction). The turning force acts to maintain the clamped state of the workpiece. In addition, after the piston is advanced by the fluid pressure, the clamp claws are opened, and after the workpiece is fitted inside the opened claws,
When the advance of the piston by the fluid pressure is released, the piston retreats by the return force, and the workpiece is clamped by the clamp claws.

Disengaging the connection between the spindle and the center, or disengaging the spindle from the rotating body, and moving the center forward or backward while rotating the center with respect to the stationary rotating body; or The rotating body is moved forward or backward while rotating the rotating body with respect to the stationary center. Then, the degree of protrusion of the front end of the center with respect to the front surface of the rotating body becomes small or large.

The screw is removed, the engagement between the protruding shaft and the hole is released, and then the clamp claws formed of an arc-shaped plate or a circular plate are rotated clockwise and counterclockwise by a predetermined angle, and thereafter, The hole and the protruding shaft are fitted in a meshing manner,
Screw the screw on the protruding shaft and attach the clamp claw to the rotating body. Then, the distance from the center to the contact point of the clamp claw with the workpiece can be changed.

[0017]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) As shown in FIGS. 1 and 2, a plurality of (in the illustrated case, three equally spaced) peripheral portions in a rotating body 2 which rotates together with a spindle 1 have cylinder chambers. 3 are provided.

The center of the rotating body 2 is provided with a center 4 having a front end projecting from the front surface of the rotating body 2. As shown in the figure, the center 4 is inserted into the recessed hole 5 on the front surface of the rotating body 2 and the terminal screw shaft 7 of the center 4 is screwed into the threaded portion 6 of the recessed hole 5 for attachment. ,
The exchange of the center 4 becomes possible.

Further, the cylinder chamber 3 is provided with a piston 8 which is restrained from rotating and which slides forward and backward by the fluid pressure from the passage.

In the case shown in the figure, the above-mentioned passage is connected to a first passage 10 for supplying a fluid to the rear side of the piston 8 of the cylinder chamber 3 through a rotary joint while piping using a through hole 9 in the axis of the spindle. And a second passage 11 for supplying a fluid to the front side of the piston 8 of the cylinder chamber 3.

As the restraining means for preventing the rotation of the piston 8, the cylinder chamber 3 and the piston 8 are formed in an elliptical shape in the illustrated case, but there are other means such as a detent by a polygon or a pin.

A through-hole 12 is provided for communicating the front surface of the rotating body 2 with each of the cylinder chambers 3. The through-hole 12 is inserted into the through-hole 12 so as to freely rotate at a fixed position. A rotatable rotating body 14 that allows the piston rod 13 to slide is fitted on the outer side of the piston rod 13 that continues from.

The above-mentioned rotating body 14 has a cylindrical shape with a closed end.
Annular groove 15 which matches the inner peripheral surface of
And the ball 16 is fitted into the annular groove 15.

Further, the piston rod 13 and the rotating body 14
A conversion device 17 for converting the advancing and retreating movement of the piston rod 13 into the rotating movement of the rotating body 14 is provided between the contact surfaces of the rotating members 14.

As shown in FIG. 1, the conversion device 17 includes a piston rod 13 on the outer peripheral surface of the piston rod 13.
A plurality of inclined grooves 18 obliquely oblique to the axis of, a part of the peripheral surface is fitted into the inclined grooves 18 and a part of the peripheral surface is fitted and held in the inner peripheral concave portion of the rotating body 14. When the piston rod 13 moves forward together with the piston 8, one end of the inclined groove 18 approaches the ball 19 at a fixed position to rotate the rotating body 14 in one direction, and when the piston rod 13 moves backward with the piston 8, Then, the other end of the inclined groove 18 approaches the ball 19 at the fixed position to rotate the rotating body 14 in the other direction.

A clamp claw 20 is attached to the tip of each rotating body 14 via a mounting bolt 21.

With the above-described structure, when fluid (air) is press-fitted into the cylinder chamber 3 from the first passage 10 and the piston 8 is advanced, the piston rod 13 moves together with the forward movement and the conversion device 17 rotates. The moving body 14 rotates.
Then, together, the clamp claw 20 rotates in the opening direction.

After the workpiece A is supplied by engaging the hole a of the end surface axis with the center 4 (as shown in FIG. 1), the fluid is pressed into the cylinder chamber 3 from the second passage 11. Then, the clamp claw 20 is rotated in a direction in which the rotating body 14 is rotated and closed by the retreating motion of the piston rod 13 and the conversion device 17 which retreat together with the retraction of the piston 8,
Workpiece A is clamped. At this time, even if there is a dimensional variation between the center 4 of the workpiece A and the outer periphery,
Clamping is performed without any trouble by the piston 8 having the piston rod 13 acting independently and the rotating body 14 with the clamp claw 20.

(Second Embodiment) As shown in FIG. 3 and FIG. 4, a first screw which is screwed on the outside of the center 4 to adjust the movement in the front-rear direction and rotates together with the spindle 1 via the engagement means 31. A rotating body 2 similar to that of the embodiment is provided.

As shown in FIG. 3, the center 4 has a tapered shank 33 connected to the center 4 inserted into the tapered hole 32 of the stationary spindle 1. As shown in FIG. 3, the cylindrical body 34 is fitted to the outside of the center 4, and screw portions 35 provided on the outer peripheral surface of the center 4 and the inner peripheral surface of the cylindrical body 34 are screwed into the cylindrical body 34. The rotating body 2 is provided outside the rotating member 34 via a bearing 36 so as to freely rotate at a fixed position. As shown in FIG. 3, the engaging means 31 includes a pin 37 provided at the tip of a rotating spindle 1 ' that rotates outside the stationary spindle 1 of the grinding machine, and a fork on the rotating body 2 side. 38, the taper shank 33 is fitted and engaged when the tapered shank 33 is fitted into the tapered hole 32. However, the present invention is not limited to this.

Further, since the center 4 is attached to the stationary spindle 1, the fluid supply passage is kept airtight at the outer peripheral end of the rotating body 2 and free rotating of the rotating body 2 as shown in FIG. A security ring 39 is provided.
A fluid is supplied from a hose 40 to a ring 39 via a connection fitting 41, and a piston 8 of the cylinder chamber 3 is supplied from a first passage 10 to a rear side of the piston 8 of the cylinder chamber 3 and a second passage (not shown). Fluid is pressed into the front side.

With the above construction, the coupling between the stationary spindle 1 and the center 4 is released, and the center 4 is advanced while rotating the center 4 in one direction with respect to the rotating body 2, or The center 4 is retracted while rotating the center 4 in the other direction with respect to 2. Then, the degree of protrusion of the tip of the center 4 with respect to the front surface of the rotating body 2 is adjusted. That is, when the clamp claw 20 is opposed to the large-diameter portion of the tapered taper of the center 4, the clamp of the workpiece A having a large center hole is small when the clamp claw 20 is opposed to the small-diameter portion of the tapered taper of the center 4. The workpiece A can be clamped.

(Third Embodiment) As shown in FIGS. 1 and 3, the piston rod 13 is provided with a backward return force.

The above-described retraction return force is applied to the piston rod 13.
Both ends of a spring 42 fitted in the hole 41 are brought into contact with the bottom of the hole 41 and the end wall of the rotating body 14. Then, the clamp force by the clamp claw 20 is maintained by the push-back force of the retreating method of the piston rod 13, so that the clamp state is maintained even if the fluid supply path is damaged or a fluid supply source fails due to some influence. Can also be the first
The fluid is pressed into the cylinder chamber 3 from the passage 10 and the piston 8
When the press-in of the fluid from the first passage 10 is released after the clamp claw 20 is opened and the end of the workpiece A is fitted between the opened clamp claws 20 and the piston 8 is pushed back by the spring 42 (retreat). ) So close clamp claw 2
The workpiece A can be clamped by 0 to process the workpiece. 2, the piston 8 may be pushed back by the spring 42.

(Fourth Embodiment) As shown in FIGS. 3 and 4, a clamp claw 20 is provided with a meshing hole 51 and an arc-shaped plate (not shown) or a disk (not shown) whose distance from the hole 51 changes successively. The hole 51 is located at the eccentric position of the disk as shown in FIG. 4), and the engaging protruding shaft 52 projecting from the tip of the rotating body 14 is fitted into the hole 51 and engaged therewith. Then, the screw 21 is screwed into the screw hole 53 of the protruding shaft 52, and the clamp claw 20 is attached. Then, the screw 21 is removed, the fitting of the protruding shaft 52 and the hole 51 is released, and then the clamp claw 20 is rotated clockwise or counterclockwise by a predetermined angle. Are fitted in a meshing manner, and the clamp claw 20 is attached to the rotating body 14 via the screw 21. When the peripheral edge of the disk is worn, the disk may be mounted upside down.

As described above, the distance between the axis of the center 4 and the clamp claw 20 can be increased or decreased. That is, the clamp claw 2 corresponding to the diameter of the workpiece A
The zero clamp can be adjusted.

The meshing fitting hole 51 and the protruding shaft 52 are not limited to the hexagonal shape having a polygonal step angle of 60 °, but may be a spline shaft and a hole. It is convenient to display the distance between the center of the center 4 and the clamp claw 20 at each step position on the plate surface of the clamp claw 20, and the hole 51 and the protruding shaft 52 may be provided in reverse.

[0039]

Since the chuck according to the present invention is configured as described above, when the workpiece is gripped on the basis of the center, the rotation can be transmitted to the workpiece without using burrs. . Therefore, the supply and discharge of the workpiece using the robot can be performed.

Further, since the clamping is carried out by the clamp claws which act independently, the clamping can be surely performed even if the dimension from the center to the outer diameter varies.

Further, since the piston rod is provided with a returning force in the retreating direction, even if a problem occurs on the fluid supply side, the clamped state can be maintained, or clamping can be performed without using fluid pressure. Can also.

Since the center is screwed into the rotating body, the degree of protrusion of the center can be adjusted. Therefore, the position of the clamp claw with respect to the tip of the center can be changed. That is, it is possible to change the clamp position according to whether the center hole of the workpiece is large or small.

Further, since the clamp claw and the rotating body are fitted with a hole and a protruding shaft which are fitted in a meshing manner, the fitting mesh is changed so that the distance from the center to the clamp contact point of the clamp claw is reduced. Can be changed.
For this reason, a dedicated clamp claw according to the diameter of the workpiece becomes unnecessary.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view of a first embodiment.

FIG. 2 is a partially cutaway front view.

FIG. 3 is a partially cutaway side view of the second embodiment.

FIG. 4 is a front view with one clamp claw removed.

[Explanation of symbols]

Reference Signs List 1 spindle 1 ' rotating spindle 2 rotating body 3 cylinder chamber 4 center 5 recessed part 6 screw part 7 screw shaft 8 piston 9 through hole 10 first passage 11 second passage 12 through hole 13 piston rod 14 rotating body 15 annular groove 16 Ball 17 Transformation device 18 Inclined groove 19 Ball 20 Clamping claw 21 Bolt 31 Engaging means 32 Tapered hole 33 Shank 34 Cylindrical body 35 Threaded portion 36 Bearing 37 Pin 38 Bifurcated piece 41 Hole 42 Spring 51 Hole 52 Projection shaft

Claims (5)

(57) [Claims] 1. A rotating body provided so as to rotate together with a spindle, a center provided with a front end protruding forward from an axis of the rotating body, and a plurality of provided at equal intervals around a peripheral edge of the rotating body. A cylinder chamber, a piston constrained from rotating by appropriate means in each of the cylinder chambers, and a piston provided to slide forward and backward by the fluid pressure supplied from the passage, and a front surface of the rotating body and the cylinder chamber. A rotating body inserted into the communicating through-hole so as to freely rotate at a fixed position, and rotatably fitted to the outside of a piston rod connected to the piston, and a contact surface between the rotating body and the piston rod. A conversion device provided to convert the reciprocating motion of the piston rod into the rotating motion of the rotating body;
A chuck comprising a clamp claw provided at a protruding end facing forward of each of the rotating bodies. 2. A rotating body provided so as to rotate together with a spindle, a center provided with a tip protruding forward from an axis of the rotating body, and a plurality of cylinders provided at equally spaced positions on the periphery of the rotating body. Chambers, pistons provided in the respective cylinder chambers so as not to rotate by appropriate means, and passages provided to apply a fluid pressure to at least a rear side of the pistons in the cylinder chambers; A rotating body which is inserted into a through hole communicating with the front surface of the body and the cylinder chamber so as to freely rotate at a fixed position, and which is rotatably fitted outside a piston rod continuous with the piston; A conversion device provided between the contact surface with the piston rod so as to convert the advancing and retreating motion of the piston rod into a rotating motion of the rotating body, and a retreat provided to the piston rod by appropriate means. A chuck comprising a return force and a clamp claw provided at a protruding end of each of the rotating bodies facing forward. 3. A center provided on the stationary spindle, and movably screwed to the outside of the front end portion of the center, and rotated outside the stationary spindle via appropriate engaging means.
A rotating body provided to rotate with the rotating spindle ;
A plurality of cylinder chambers provided at equally-spaced peripheral portions in the rotating body, and each cylinder chamber is provided so as to be restrained from rotating by appropriate means and to slide forward and backward by fluid pressure supplied from a passage. The piston, and the front surface of the rotating body and the cylinder chamber are inserted so as to freely rotate at a fixed position in a through hole communicating therewith, and rotatably fitted to the outside of a piston rod connected to the piston. A rotating body, a conversion device provided on a contact surface between the rotating body and the piston rod so as to convert an advancing / retreating movement of the piston rod into a rotating movement of the rotating body, and a forward end of each of the rotating bodies. Chuck comprising a clamp claw provided at 4. A center provided on a stationary spindle, and is movably screwed to the outside of the tip of the center, and is rotated outside the stationary spindle via an appropriate engaging means.
A rotating body provided to rotate with the rotating spindle ;
A plurality of cylinder chambers provided at equally-spaced peripheral portions in the rotating body; a piston provided in each cylinder chamber so as not to rotate by appropriate means; and at least a rear side of the piston in the cylinder chamber. Into the passage provided to apply fluid pressure to the through hole through which the front surface of the rotating body and the cylinder chamber communicate with each other so as to rotate freely at a fixed position, and rotate outside the piston rod connected to the piston. A rotating body fitted movably, a conversion device provided between a contact surface of the rotating body and the piston rod, for converting an advancing and retreating motion of the piston rod into a rotating motion of the rotating body, and the piston; A chuck comprising a return force applied to the rod by an appropriate means, and a clamp claw provided at a forwardly protruding end of each of the rotating bodies. 5. The clamping claw comprises a meshing hole, an arc-shaped plate or a disc whose distance from the hole changes successively, and is fitted with a meshing projecting shaft at the projecting end of the rotating body and the hole. The chuck according to any one of claims 1 to 4, wherein the clamp claws are attached by screws screwed into the protruding shaft.