JP2561750Y2 - 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 for attaching a tool such as a tap or a drill to a machine tool.

[0002]

2. Description of the Related Art Conventionally, as a chuck of this type, there is a chuck proposed by the present applicant in Japanese Utility Model Laid-Open Publication No. 2-97505. That is, as shown in FIG. 4, a cylindrical portion 32 is formed in the chuck main body 31, and the cylindrical portion 32 is provided with a mounting hole 33. A square hole 36 is provided on the inner bottom surface of the mounting hole 33, and a prism 37 a of a tap 37 as a tool inserted into the mounting hole 33 is inserted and fixed. Further, a plurality of insertion grooves 38 are formed in the inner periphery of the front end of the mounting hole 33. The insertion grooves 38 are provided with a deep retreating portion 39 and an oblique portion extending in front of the retreating portion 39 so that the depth decreases. And a shape portion 40.

A mounting cylinder 41 is mounted in the mounting hole 33 so as to be slidable in the front-rear direction. The mounting cylinder 41 has an insertion hole 44 through which the tap 37 is inserted. A storage recess 45 is provided at the rear of the mounting cylinder 41.
And a notch 46 are formed.

[0004] A coil spring 47 is provided between the housing recess 45 and the inner bottom surface of the mounting hole 33 to constantly urge the mounting cylinder 41 strongly forward. The front end portion 47a of the coil spring 47 is formed in an oval shape extending vertically long. And the front end portion 47a is the mounting cylinder 4
It is engaged in the notch 46 and projects outward from the outer peripheral surface of the mounting cylinder 41. When the mounting cylinder 41 is pushed forward by the coil spring 47, the projection 47 comes into contact with a front wall 35a formed in the mounting hole 33 to restrict the forward movement position of the mounting cylinder 41. Has become.

[0005] A plurality of holes 48 are provided in the shaft portion 42 of the mounting cylinder 41, and a ball 49 is movably inserted into each of the holes 48. Each ball 49 is retracted into the retreat portion 39 when it corresponds to the retreat portion 39 of the insertion groove 38, and is pushed out into the insertion hole 44 when it corresponds to the inclined portion 40.

Accordingly, when the tap 37 is not inserted, the mounting cylinder 41 is strongly pushed forward by the coil spring 47, and each ball 49 is slightly pushed out into the insertion hole 44 by the inclined portion 40 of the insertion groove 38. Then, when the tap 37 is inserted and the mounting cylinder 41 is slid rearward against the elasticity of the coil spring 47, the retracting portion 3 of the insertion groove 38 is formed.
Since the spheres correspond to 9, these spheres 49 can be retracted from the inside of the insertion hole 44.

[0007] The chuck constructed as described above, when assembling the mounting cylinder 41 to the chuck body 31, when inserting the mounting cylinder 41 into the mounting hole 33,
A stopper 47b formed integrally with the mounted coil spring 47 is pressed into the mounting hole 33, deformed and immersed in the notch 46, and does not hinder the insertion of the mounting cylinder 41. In a state where the mounting cylinder 41 is assembled to the chuck body 31, the stopper 47b projects from the notch 46 by its own elastic force and abuts on the front wall 35a provided in the mounting hole 33, The front movement position of the mounting cylinder 41 is regulated.

[0008]

However, according to the prior art, the mounting cylinder 41 inserted into the mounting hole 33 of the chuck body 31 has a stopper 47b integral with the coil spring 47 and a notch 46 of the mounting cylinder 41. From the mounting hole 33 and is prevented from falling off by engaging with the front wall 35a of the mounting hole 33. Since the stopper 47b has elasticity, when the mounting cylinder 41 is inserted into the chuck body 31, the notch 46b engages with the chuck body 31.
Although it is immersed in the inside and does not hinder the insertion of the mounting cylinder 41, the mounting cylinder 41
Need to be removed from the mounting hole 33, the front wall 35a
The stopper 47b abutted on the mounting cylinder 41 hinders the movement of the mounting cylinder 41 in the extracting direction. For this reason, the work of disassembling the chuck has been extremely difficult.

The mounting cylinder 41 is locked only by a stopper 47b abutting on the front wall 35a. For this reason,
Stress concentration acts on the stopper 47b to shorten the life of the coil spring 47.

The present invention has been made in view of the problems existing in the prior art described above, and its object is to make it possible to easily remove the mounting cylinder from the chuck body and to use the chuck. > replacement of sphere or spring material constituting can be easily, moreover, it is to provide a chuck which can assembly or removal of the chuck body of no hollow mounting applying unreasonable load on a spring member.

[0011]

In order to solve the above-mentioned problems, the present invention provides a chuck body in which a female screw is formed on a part of an inner peripheral surface of a mounting hole provided in a cylindrical portion, It has an external thread which meshes with the outer peripheral surface, and a mounting cylinder insertion holes are formed through the tool attachment such as tapping, attached to the tubular portion, a spring member for always urging forwardly the hollow mounting, said mounting A plurality of balls provided on the cylinder, which are protruded and retracted into the insertion hole by the forward and backward movement of the mounting cylinder, and which engage with a shank such as a tap when protruding into the insertion hole to prevent the ball from coming off; And a square hole for inserting a prism such as a tap so as to be relatively non-rotatable. A mounting cylinder is inserted into the mounting hole by screwing, and a mesh between the male screw and the female screw is formed in the mounting hole. It comes off at the back, and the threads of the same male screw and female screw come in contact Is obtained by configured to prevent inadvertent said hollow mounting by.

Further, in order to solve the above-mentioned problems, in the present invention, the spring member is a coil spring.

[0013]

[Action] In the chuck having the above structure, when only assembling of the chuck body of the mounting tube, when inserting the hollow mounting in the mounting hole, near the mounting tubular tip with female thread formed in the mounting hole periphery With a male screw formed on the outer peripheral surface of the. Since the female screw and the male screw are respectively formed in the mounting hole and only a part of the mounting cylinder, when the mounting cylinder is rotated a plurality of times, the engagement between the male screw and the female screw is disengaged at the inner part of the mounting hole. Although the hollow mounting is urged by a coil spring as a spring member which is inserted into the mounting hole, the thread of the male screw and the female screw falling out of the mounting tube by abutment is prevented.

When the mounting cylinder is removed to replace a coil spring, a ball, or the like, the mounting cylinder is rotated in the opposite direction to the insertion, so that the male screw and the female screw are meshed, and further rotated a plurality of times. Can be removed by

[0015]

EXAMPLES Hereinafter, a description will be given of an embodiment in which the chuck of the present invention is embodied in accordance with FIGS.

As shown in FIGS. 1 to 3, a cylindrical portion 2 is formed in a chuck body 1 attached to a machine tool such as a drilling machine, and the cylindrical portion 2 has a large diameter opening at a front end face. A mounting hole 3 including a hole 4 and a small diameter hole 5 formed at the inner end of the large diameter hole 4 is provided. A square hole 6 is provided on the inner bottom surface of the mounting hole 3, and a prism 7 a of a tap 7 as a tool inserted into the mounting hole 3 is inserted and fixed. A plurality of insertion grooves 8 are formed in the inner periphery of the front end portion of the mounting hole 3 in the circumferential direction. The insertion grooves 8 have a deeper retreating portion 9 and a shallower depth in front thereof. And a slanted portion 10 that follows. Further, a female screw 5b is formed in the circumferential direction of the front wall 5a of the small diameter hole 5.

A mounting cylinder 11 is mounted in the mounting hole 3 so as to be slidable in the front-rear direction. The mounting cylinder 11 includes a shaft 12 inserted into the mounting hole 3 and the shaft 1.
A flange 13 is formed integrally with the front end of the shaft 2. An insertion hole 14 into which the tap 7 is inserted is formed in the shaft 12 and the flange 13 in a front-rear direction. On the outer periphery of the shaft portion 12 located at the front end of the mounting cylinder 11, a male screw 12 a that can mesh with the female screw 5 b is formed over the entire circumference, and the insertion of the mounting cylinder 11 into the chuck body 1 is performed by using the male screw 12 a and the female screw 5b is rotated, and the mounting cylinder 11 is rotated a plurality of times, so that the engagement between the male screw 12a and the female screw 5b is
It is performed by coming off at the back.

A coil spring 15 is interposed between the front end of the mounting cylinder 11 and the inner bottom surface of the mounting hole 3 as a spring material for constantly urging the mounting cylinder 11 forward. The coil spring 15 is constituted by a number of annular portions. The coil spring 15 is inserted between the front end of the mounting cylinder 11 and the inner bottom surface of the mounting hole 3 and constantly urges the mounting cylinder 11. The male screw 12
The thread of a is mounted on the mounting cylinder 11 by the coil spring 15.
When it is pushed forward, it comes into contact with the thread of the female screw 5b of the front wall 5a to regulate the forward movement position of the mounting cylinder 11.

The flange portion 1 is formed on the shaft portion 12 of the mounting cylinder 11.
3, a plurality of holes 1 through which the coaxial portion 12 penetrates inside and outside.
A ball 17 is inserted into each hole 16 so as to be movable inward and outward. At the inner end of each hole 16, a locking projection 16a for preventing the ball 17 from dropping into the insertion hole 14 of the mounting cylinder 11 is formed.
Each ball 17 is retracted into the retracting portion 9 when corresponding to the retracting portion 9 of the insertion groove 8, and is pushed out into the insertion hole 14 when corresponding to the inclined portion 10.

Therefore, when the tap 7 is not inserted, the mounting cylinder 11 is strongly pushed forward by the coil spring 15, and each ball 17 is inserted into the insertion hole 1 by the inclined portion 10 of the insertion groove 8.
4 is slightly pushed out. Then, when the tap 7 is inserted and the mounting cylinder 11 is slid backward against the elasticity of the coil spring 15, the ball 17 is inserted into the retreat portion 9 of the insertion groove 8.
Correspond, these balls 17 can be retracted from the inside of the insertion hole 14.

Next, in the present embodiment constructed as described above,
The operation and effect of the chuck will be described. First, when removing the tap 7 from the state of FIG. 1, as shown in FIG.
The mounting cylinder 11 is slid backward. By doing so, the plurality of balls 17 can be retracted into the retreat portion 9 of the insertion groove 8, and the tap 7 can be easily removed by manually removing the shank 7b from the tubular portion 2.

After the tap 7 is removed, the mounting cylinder 11 is projected forward by the action of the coil spring 15 as shown in FIG. In this state, the thread of the male screw 12a of the shaft portion 12 of the mounting cylinder 11 abuts on the thread of the female screw 5b formed on the front wall 5a of the small-diameter hole 5, and the mounting cylinder 11 is prevented from slipping forward. You.

When another tap 7 is to be attached to the chuck body 1 in a state where the mounting cylinder 11 is completely protruded as described above, the tap 7 is inserted into the insertion hole 14 of the mounting cylinder 11. Then, the shank 7b of the tap 7 is attached to the mounting cylinder 1.
The mounting cylinder 11 engages with the inner protruding surface of the ball 17 and retracts into the mounting hole 3 together with the tap 7 against the urging force of the coil spring 15. When the mounting tube 11 is retracted, the ball 17 moves to the inner part of the inclined portion 10 of the insertion groove 8 and is pushed out of each hole by the shank 7b.
Is disengaged from the shank 7b.

Then, the shank 7b is inserted deeply into the insertion hole 14. At this time, when the prism 7 a of the tap 7 is not properly inserted into the square hole 6 of the chuck body 1, the tap 7 is slightly rotated in the insertion hole 14. Then, the prism portion 7a is inserted into the inside corresponding to the square hole 6, and as a result, the tap 7 cannot rotate with respect to the chuck body 1.

In this state, as shown in FIG. 1 , the mounting cylinder 11 is strongly pushed forward by the coil spring 15 so that the balls 17 are pushed into the insertion holes 14, and these balls 17 are pushed into the shank 7b of the tap 7. Since the tap 7 is pressed against the outer periphery, the tap 7 cannot be pulled out from the chuck body 1.

By the way, the hollow mounting 11 to Keru assembling the chuck body 1, inserting the coil spring 15 into the mounting hole 3 as shown in FIG. Then, the front end face of the female screw 5b formed in the mounting hole 3 is brought into contact with the distal end surface of the male screw 12a formed at the distal end of the mounting cylinder 11, and when the mounting cylinder 11 is rotated, the female screw 5b and the male screw 12a are engaged with each other. The mounting cylinder 11 is sent toward the back of the mounting hole 3. At this time, since the female screw 5b and the male screw 12a are formed only partially in the mounting hole 3 and the length direction of the mounting cylinder 11, respectively, when the mounting cylinder 11 is rotated a plurality of times, the male screw 12a and the female screw 12a are formed. 5b is disengaged at the back of the mounting hole 3. The mounting cylinder 11 is always urged forward by the coil spring 15, but the mounting cylinder 11 cannot be pulled out of the chuck body 1 due to the contact of the thread.

As described above, in this embodiment, the mounting holes 3
The mounting tube 11 is pulled out by abutting the thread of the male screw 12a of the shaft portion 12 and the thread of the female screw 5b formed on the front wall 5a of the small-diameter hole 5 in the mounting tube 11 disengaged from the back of the mounting tube 11. Stopper to prevent. Therefore, it is not necessary to the front annular portion of the conventional coil spring 15 as deformed into an oval shape, it can be simplified the structure of the coil spring 15.

In addition, conventionally, the mounting cylinder 1 is
In the present embodiment, it is difficult to remove the mounting cylinder 11 because the movement of the mounting cylinder 11 in the removal direction is restricted. By rotating the mounting cylinder 11, the coil spring 15 and the ball 17 can be easily replaced.

Further, the mounting cylinder 11 is attached to the chuck body 1.
Since there is no need to apply a load to the coil spring 15 in a direction other than the urging direction at the time of assembly or removal, the life of the coil spring 15 is extended.

The present invention is not limited to the above embodiment, but can be implemented in the following manner without departing from the gist of the present invention. (1) A step is provided on the outer peripheral surface of the shaft portion 12 of the mounting cylinder 11, and the coil spring 15 is mounted on the shaft portion 12 between the step and the inner bottom surface of the mounting hole 3. (2) A step is provided on the inner peripheral surface of the shaft portion 12 of the mounting cylinder 11, and the coil spring 15 is mounted in the shaft portion 12 between the step and the inner bottom surface of the mounting hole 3. (3) In the above (1) or (2), a concave portion is provided on the inner bottom surface of the mounting hole 3, and the coil spring 15 is mounted on the shaft between the concave portion and the step.

[0031]

[Effects of the Invention] As described in detail above, the chuck of the present invention is easy to assemble and remove the mounting cylinder to and from the chuck body, and easily disassemble for replacing coil springs and balls. It has the effect of gaining.

Further, since there is no need to provide a complicated stopper structure for the coil spring and the mounting cylinder, it can be easily manufactured. Further, it is not necessary to apply a load other than the biasing direction to the coil spring at the time of assembling or removing the mounting cylinder from / to the chuck body.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a state in which a tap is mounted on a chuck according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the chuck in a state where a tap is not mounted.

FIG. 3 is a sectional view showing positions of a mounting cylinder and a ball when a tap is removed from a chuck .

FIG. 4 is a partial sectional view showing the vicinity of a stopper of a conventional chuck .

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Chuck body, 2 ... Cylindrical part, 3 ... Mounting hole, 5b ... Female screw, 6 ... Square hole, 7 ... Tap, 7a ... Square column part, 7b ... Shank, 11 ... Mounting cylinder, 12a ... Male screw, 14 ... Insertion Hole, 15: Coil spring as spring material, 17: Ball

Claims (2)

(57) [Scope of request for utility model registration] 1. A chuck body in which a female screw is formed on a part of an inner peripheral surface of a mounting hole provided in a cylindrical portion, and a male screw which meshes with the female screw on an outer peripheral surface, and an insertion hole for mounting a tool such as a tap. There a mounting tube which is pierced, mounted on the tubular portion, a spring member for urging the hollow mounting always forward, provided on the mounting tube, are infested into the insertion hole by back-and-forth movement of the mounting cylinder A plurality of balls that engage with a shank such as a tap when protruding into the insertion hole to prevent the ball from coming off, and a prism such as a tap that is provided at the back of the mounting hole and cannot be relatively rotated. The mounting cylinder is inserted into the mounting hole by screwing, and the engagement between the male screw and the female screw is disengaged at the inner part of the mounting hole, and the male screw and the female screw are in contact with each other. Make sure that the mounting tube is Chuck according to claim. 2. The chuck according to claim 1, wherein the spring member is a coil spring.