JPH08309608A - Chuck - Google Patents

Abstract

PURPOSE: To provide a chuck, which can clamp a work to be held on the basis of the center reference with separate clamp claw. CONSTITUTION: A center 4 is provided in an axis center of a rotator 2 to be rotated with a spindle, and a piston rod 13 to be slide with a piston 8 by the fluid pressure acting upon plural cylinder chambers 3 provided in the rotator 2 is provided, and clamp claws 20 is provided in a turning body 14, which is rotated by a converter 17 freely to be reversely rotated, and a work is clamped by each clamp claw 20.

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 a shaft center of a workpiece by a center and gripping an outer peripheral surface of the workpiece to transmit rotation.

[0002]

2. Description of the Related Art Conventionally, when gripping a workpiece with a center as a reference, the center on the chuck side and the center on the tailstock side support the centers of both ends of the workpiece, and Rotation of the chuck is transmitted to the workpiece by engaging with the chuck.

[0003]

According to the above-mentioned gripping method, since the tool is attached to and detached from the work piece, it takes a great deal of work and the working rate of the working machine is remarkably lowered.

Further, since the kerbs are used, it is not possible to automate the attachment and detachment of the workpiece by the robot.

Further, if the attachment of the skeins is incomplete, the rotation will be poorly transmitted due to slip and the tool such as the cutting tool will be damaged.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to transmit rotation to a work piece held on the basis of a center without using skeins.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is provided with a rotary member provided so as to rotate together with a spindle, and a shaft body of which the tip is projected forward. A center, a plurality of cylinder chambers provided at equidistant positions in the peripheral portion of the rotating body, and restrained from rotating by appropriate means in each of the cylinder chambers, and sliding forward and backward by a fluid pressure supplied from a passage. A piston provided in the piston, a front surface of the rotating body, and the cylinder chamber to communicate with each other so as to freely rotate at a fixed position, and rotatably fitted to the outside of a piston rod connected from the piston. A rotating body, a conversion device provided between the contact surfaces of the rotating body and the piston rod so as to convert the forward / backward movement of the piston rod into the rotating movement of the rotating body, and the rotating bodies. Employing a chuck comprising a clamping claw provided on the projecting end facing forward.

[0008] Further, a rotating body provided so as to rotate together with the spindle, a center provided with its tip projecting forward on the axis of the rotating body, and a plurality of cylinders provided at equidistant positions on the periphery of the rotating body. A chamber, a piston provided in each of the cylinder chambers so as not to rotate by an appropriate means, a passage provided to apply a fluid pressure to at least the rear side of the piston in the cylinder chamber, and the rotation A rotating body which is inserted into a through hole that communicates the front surface of the body with the cylinder chamber so as to freely rotate at a fixed position, and is rotatably fitted to the outside of a piston rod connected from the piston, and the rotating body. A conversion device provided between the contact surface with the piston rod so as to convert the forward / backward movement of the piston rod into the rotational movement of the rotating body, and the conversion device is provided to the piston rod by appropriate means. 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 spindle, a rotating body provided so as to be movably screwed to the outside of the tip portion of the center, and rotated together with the spindle through an appropriate engaging means, and a peripheral portion of the rotating body. A plurality of cylinder chambers provided at equal intervals, a piston provided in each of the cylinder chambers so as not to rotate by an appropriate means, and a piston provided so as to slide forward and backward by a fluid pressure supplied from a passage; A rotating body that is inserted into a through hole that communicates the front surface of the body with the cylinder chamber so as to freely rotate at a fixed position, and is rotatably fitted to the outside of a piston rod that connects the piston, and A conversion device provided on the contact surface between the moving body and the piston rod so as to convert the forward / backward movement of the piston rod into the rotational movement of the rotary body, and in front of each rotary body. Employing a chuck comprising a clamping claw provided on Ku projecting end.

Further, a center provided on the spindle, a rotating body provided so as to be movably screwed to the outside of a tip end portion of the center and rotating together with the spindle through an appropriate engaging means, and a peripheral portion of the rotating body. A plurality of cylinder chambers provided at equal intervals, a piston constrained in each cylinder chamber so as not to rotate by an appropriate means, and a fluid pressure acting on at least the rear side of the piston in the cylinder chamber. And a through hole through which the front surface of the rotor and the cylinder chamber communicate with each other so as to freely rotate at a fixed position, and rotatably fitted on the outside of a piston rod connected from the piston. A rotating body and a conversion device provided between the contact surface between the rotating body and the piston rod so as to convert the forward / backward movement of the piston rod into the rotating movement of the rotating body. Employing a chuck comprising a a return force applied by the appropriate means to the piston rod, the clamp jaws provided in projecting end facing the front of the each time the moving object.

Further, the above-mentioned clamp claw is composed of a mesh-shaped hole and an arc-shaped plate or a circular plate whose distance from the hole is successively changed. The mesh-shaped protruding shaft and the hole of the projecting end of the rotating body are fitted into the clamp claw. In addition, the chuck according to any one of claims 1 to 4, wherein the clamp claw is attached by a screw screwed into the protruding shaft.

[0012]

With the above construction, when the fluid is press-fitted from the passage to the rear side of the piston in the cylinder chamber and the piston is advanced, the rotary body is rotated by the sliding motion of the piston rod and the conversion device which move together. . Then, both clamp claws open (the distance between the clamp claws increases).
Turn to.

After the center of the end face is engaged with the center to supply the workpiece, the fluid is press-fitted into the front and rear of the piston in the cylinder chamber from the passage. Then, since the piston rod retracts together with the piston, the rotating body rotates due to the sliding movement of the piston rod and the converting device, and the work piece is clamped by the crank claws that rotate in the closing direction, and rotates together with the spindle. The rotation of the body is transmitted to the work piece.

Even if the press-fitting of the fluid is interrupted due to some influence during machining (during clamping), the piston rod is pushed back together with the piston rod (retracting direction) due to the restoring force applied to the piston rod. The rotating force of the force acts to maintain the clamped state of the work piece. In addition, after the piston is moved forward by fluid pressure to open the clamp claw and insert the work piece inside the opened claw,
When the advance of the piston due to the fluid pressure is released, the piston retracts due to the return force and the workpiece is clamped by the clamp claw.

The spindle and the center are released from the connection, or the engagement between the spindle and the rotating body is released, and the center is moved 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 center in the stationary state. Then, the degree of protrusion of the tip of the center with respect to the front surface of the rotating body is reduced or increased.

After removing the screws, the engagement between the protruding shaft and the hole is released, and then the clamp claws made of an arc-shaped plate or a circular plate are rotated in the clockwise direction and the counterclockwise direction by a predetermined angle, respectively. Fit the hole and the salient shaft into a meshed shape,
Screw the screw into 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, the cylinder chambers are arranged at equal intervals among a plurality of peripheral portions (three in the case shown) in a rotating body 2 which rotates together with the spindle 1. 3 is provided.

The center of the rotary body 2 is provided with a center 4 whose front end projects from the front surface of the rotary body 2. As shown in the drawing, when 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 to be attached. ,
The center 4 can be replaced.

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

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

As the restraint means for preventing the piston 8 from rotating, the cylinder chamber 3 and the piston 8 are formed into an elliptical shape in the illustrated case, but there are other means such as a polygonal stop and a pin to prevent rotation.

Further, a through hole 12 for communicating the front surface of the rotating body 2 with each cylinder chamber 3 is provided, and the through hole 12 is fitted so as to freely rotate at a fixed position, and the piston 8 is provided. A rotatable body 14 that allows the piston rod 13 to slide is fitted on the outer side of the piston rod 13 that is continuous with.

The rotating body 14 has a cylindrical shape with its tip closed, and means for freely rotating at a fixed position is the through hole 12.
Annular groove 15 that matches the inner peripheral surface of the rotor and the outer peripheral surface of the rotating body 14.
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 forward / backward movement of the piston rod 13 into the rotary movement of the rotary body 14 is provided between the contact surfaces with and.

As shown in FIG. 1, the conversion device 17 has a piston rod 13 formed on the outer peripheral surface of the piston rod 13.
A plurality of inclined grooves 18 obliquely intersecting with the axis of the ball 19 and a ball 19 having a part of the peripheral surface fitted in the inclined groove 18 and a part of the peripheral surface fitted and retained 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 the piston rod 13 moves backward together with the piston 8. 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 structure, when fluid (air) is forced into the cylinder chamber 3 from the first passage 10 to move the piston 8 forward, the piston rod 13 is moved forward by the forward movement of the piston rod 13 and the converter 17. The moving body 14 rotates.
Then, the clamp claws 20 rotate together in the opening direction.

After the workpiece A is supplied by engaging the hole a of the end face shaft center 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 reciprocating movement of the piston rod 13 and the converting device 17 that retreat together with the retreat of the piston 8 causes the revolving body 14 to revolve and rotate the clamp claw 20 in the closing direction.
The work piece A is clamped. At this time, even if there is a dimensional variation between the center 4 of the processed portion A and each portion of the outer periphery,
The piston 8 having the piston rod 13 acting independently of each other and the rotating body 14 with the clamp claw 20 clamp the workpiece without any trouble.

(Second Embodiment) As shown in FIGS. 3 and 4, a first member is screwed into the outside of the center 4 for adjusting the movement in the front-rear direction, and is rotated together with the spindle 1 through an engaging means 31. A rotary body 2 similar to that of the embodiment is provided.

As shown in FIG. 3, the center 4 is fitted with a tapered shank 33 extending from the center 4 into the tapered hole 32 of the spindle 1, and the rotary body 2 is screwed into the center 4 as shown in FIG. The cylindrical body 34 is fitted on the outside of the center 4, and the 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 bearing 36 on the outside of the cylindrical body 34. The rotating body 2 is provided so as to freely rotate at a fixed position via the. The engaging means 31 is, as shown in FIG. 3, a pin 37 provided at the tip of the rotary spindle 1 that rotates outside the stationary spindle 1 of the grinder, and a forked piece 38 on the rotary body 2 side. The space is adapted to be fitted and engaged when the taper shank 33 is fitted into the taper hole 32, but the invention is not limited thereto.

Further, since the center 4 is attached to the spindle 1, the fluid supply passage has a rotating body 2 as shown in FIG.
A ring 39 that maintains airtightness and ensures free rotation of the rotating body 2 is provided at the outer peripheral end of the ring, and a fluid is supplied from the hose 40 to the ring 39 through the connection fitting 41 to the ring 39. From the passage 10 to the rear side of the piston 8 in the cylinder chamber 3, and from the second passage (not shown) to the cylinder chamber 3
The fluid is press-fitted into the front side of the piston 8.

With the above construction, the connection between the spindle 1 and the center 4 is released, and the center 4 is rotated with respect to the rotating body 2.
The center 4 is moved forward while rotating in one direction, or the center 4 is moved backward while rotating the center 4 in the other direction with respect to the rotating body 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, the clamp claw 2 is attached to the large-diameter portion of the taper of the center 4.
When 0 faces each other, the clamp of the work piece A having a large center hole is clamped on the small diameter portion of the center 4 having the tapered taper 2
When 0s face each other, the work part A having a small center hole 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-mentioned backward return force is applied to the piston rod 13
Both ends of the spring 42 fitted in the hole 41 are brought into contact with the bottom of the hole 41 and the tip wall of the rotating body 14. Then, the pushing force of the method of retracting the piston rod 13 maintains the clamping force of the clamp claw 20, so that the clamped state is maintained even if the fluid supply path is damaged or the fluid supply source fails due to some influence. Can also be the first
The fluid is press-fitted into the cylinder chamber 3 from the passage 10 and the piston 8
While the clamp claw 20 is opened while advancing, the end of the workpiece A is fitted between the opened clamp claws 20, and when the press-fitting of the fluid from the first passage 10 is released, the piston 42 is pushed back (retracted) by the spring 42. ) So close clamp claw 2
The work piece A is clamped by 0, and the work piece can be processed. Note that, as shown in FIG. 2, the piston 8 may be pushed back by the spring 42.

(Fourth Embodiment) As shown in FIGS. 3 and 4, the clamp claw 20 has a meshing hole 51, and an arc-shaped plate (not shown) or a disk (not shown) whose distance from the hole 51 changes sequentially. The hole 51 is located at an eccentric position of the disc as shown in FIG. 4), and a projecting shaft 52 of a meshing shape protruding from the tip of the rotating body 14 is fitted into the hole 51 and meshed with each other. The screw 21 is screwed into the screw hole 53 of the protruding shaft 52 to mount the clamp claw 20. Then, the screw 21 is removed, the fitting between 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, respectively, and then the hole 51 and the protruding shaft 52 are removed. Are engaged with each other in a meshing manner, and the clamp claw 20 is attached to the rotating body 14 via the screw 21. If the peripheral edge of the disc wears, the disc may be turned over and attached.

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 according to the diameter of the workpiece A
The clamp by 0 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 ° shown in the figure, and a spline shaft, a hole, and the like are conceivable. In addition, it is convenient to display the distance between the axis 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 work piece is gripped with the center as a reference, the rotation can be transmitted to the work piece without the use of vignetting. . Therefore, it becomes possible to supply and discharge the workpiece using the robot.

Further, since the clamps are adapted to be clamped by the respective self-actuating clamps, the clamps can be reliably clamped even if the size from the center to the outer diameter varies.

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

Further, since the center is screwed into the rotating body, the degree of protrusion of the tip 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, the clamp position can be changed depending on whether the center hole of the workpiece is large or small.

Further, since the holes for engaging the clamp claws and the rotating body with each other in a meshing manner and the projecting shafts are mounted, the meshing engagement is changed to change the distance from the center to the clamp contact point of the clamp claws. Can be changed.
For this reason, a dedicated clamp claw corresponding to the diameter of the workpiece is unnecessary.

[Brief description of 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]

 1 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 Converter 18 Inclined groove 19 Ball 20 Clamp claw 21 Bolt 31 Engaging means 32 Tapered hole 33 Shank 34 Cylindrical body 35 Screw part 36 Bearing 37 Pin 38 Two-pronged piece 41 Hole 42 Spring 51 Hole 52 Projection shaft

Claims (5)

[Claims] 1. A rotating body provided so as to rotate together with a spindle, a center provided with its tip projecting forward from an axis of the rotating body, and a plurality of centers provided at equidistant positions in a peripheral portion of the rotating body. A cylinder chamber, a piston which is constrained from rotating by an appropriate means in each of the cylinder chambers, and which is provided so as to slide forward and backward by a fluid pressure supplied from a passage, a front surface of the rotating body, and the cylinder chamber. A rotating body which is inserted into a communicating through hole so as to freely rotate at a fixed position, and is rotatably fitted to the outside of a piston rod continuous from the piston, and a contact surface between the rotating body and the piston rod. A conversion device provided to convert the forward / backward movement of the piston rod into the rotational movement of the rotating body;
A chuck comprising a clamp claw provided on a front end of each of the rotary bodies. 2. A rotating body provided so as to rotate together with a spindle, a center provided with its tip projecting forward from the axis of this rotating body, and a plurality of cylinders provided at equidistant positions on the periphery of the rotating body. A chamber, a piston provided in each of the cylinder chambers so as not to rotate by an appropriate means, a passage provided to apply a fluid pressure to at least the rear side of the piston in the cylinder chamber, and the rotation A rotating body which is inserted into a through hole that communicates the front surface of the body with the cylinder chamber so as to freely rotate at a fixed position, and is rotatably fitted to the outside of a piston rod connected from the piston, and the rotating body. A conversion device provided between the contact surface with the piston rod so as to convert the forward / backward movement of the piston rod into the rotational movement of the rotating body, and the retraction provided to the piston rod by appropriate means. A chuck comprising a restoring force and a clamp claw provided on a protruding end of each of the rotating bodies facing the front. 3. A center provided on the spindle, a rotating body provided so as to be movably screwed to the outside of the tip end portion of the center, and rotated together with the spindle through an appropriate engaging means, and a peripheral portion of the rotating body. A plurality of cylinder chambers provided at equal intervals, a piston provided in each of the cylinder chambers so as not to rotate by an appropriate means, and provided so as to slide forward and backward by a fluid pressure supplied from a passage,
A rotating body that is inserted into a through hole that connects 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 that is continuous from the piston, A conversion device provided on the contact surface between the rotating body and the piston rod so as to convert the forward / backward movement of the piston rod into the rotating movement of the rotating body, and a clamp provided at a protruding end of each rotating body facing forward. A chuck consisting of claws. 4. A center provided on the spindle, a rotor provided so as to be movably screwed to the outside of the tip of the center, and rotated together with the spindle through an appropriate engaging means, and a peripheral portion of the rotor. A plurality of cylinder chambers provided at equal intervals, a piston constrained in each cylinder chamber so as not to rotate by an appropriate means, and a fluid pressure acting on at least the rear side of the piston in the cylinder chamber. And a through hole through which the front surface of the rotor and the cylinder chamber communicate with each other so as to freely rotate at a fixed position, and rotatably fitted on the outside of a piston rod connected from the piston. A rotating body, a conversion device provided between the contact surface between the rotating body and the piston rod so as to convert the forward / backward movement of the piston rod into the rotating movement of the rotating body; A chuck composed of a restoring force applied to the piston rod by an appropriate means and a clamp claw provided on a front end of each of the rotating bodies. 5. The clamp claw comprises an intermeshing hole and an arc-shaped plate or a circular plate whose distance from the hole sequentially changes, and the intermeshing protruding shaft and the hole at the protruding end of the rotating body are fitted into the clamp claw. The chuck according to any one of claims 1 to 4, wherein the clamp claw is attached by a screw screwed into the protruding shaft.