JP3007591B2 - How to attach and detach top jaws on 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 grasping a workpiece in a machine tool, and is particularly characterized by a method of attaching and detaching a top jaw.

[0002]

2. Description of the Related Art The present invention is an improvement of the prior application (Japanese Patent Application Laid-Open No. 63-93504) previously proposed by the present applicant. The feature of this prior application is that the master jaw and the top jaw are provided with seating means for forcibly seating the top jaw on the master jaw, and a mechanism for engaging the top jaw with the master jaw. The point is that the joining means is provided so as to sandwich the seating means in the center.

[0003]

SUMMARY OF THE INVENTION The present invention has a drawback inevitably generated from the configuration of the prior application, that is, the top jaw is completely removed from the master jaw every time the gripping diameter of the workpiece changes. Frequent attachment and detachment work of attaching another top jaw again occurs.Also, each time the master jaw is moved in the radial direction of the body by the power source that operates the chuck, the jaw recombination process which is a part of the movement process Therefore, since the top jaw is attached and detached , many operations are required for attaching and detaching work, and a complicated recombination structure is required. The present invention has been proposed in view of the above circumstances, and an object of the present invention is to make it possible to attach / detach a top jaw at an arbitrary position irrespective of movement of a master jaw, and to easily and reliably attach / detach a top jaw.
An object of the present invention is to provide a method of attaching and detaching a top jaw to and from a chuck in which accuracy after attaching and detaching is secured .

[0004]

According to the present invention, however, the engaging means for engaging the top jaw and the master jaw has a special structure to be described later, and has a reasonable assembly procedure. The feature is that the master jaw and the top jaw that engages with the master jaw are formed from a part of a cone at a site where the both engage.
An engaging means consisting of a convex portion and a concave portion is provided, and a part of the cone is cut into a width B in the concave portion of the engaging means to be incorporated into the convex portion.
Divided by the embedded portion is formed, <br/> guide portion both sides were excised width A of the cone is formed to guide the <br/> width B of the embedded portion of the recess in the convex portion, and When attaching and detaching the top jaw using the top jaw and the master jaw in which both widths are formed in B> A, the width A of the built-in portion is added to the width A of the guide portion.
Lies in removing or inserting a top jaw forms a step and a top jaw to insert a B to a step you rotational movement relative to the axis of the cone.

The operation of the present invention will now be described with reference to FIGS. FIG. 5 shows a master jaw according to the present invention, in which engagement means for engaging with the top jaw is provided as a part of a cone, and the width of the guide portion in the circumferential direction of the body of the master jaw. A for both sides of the cone
The face has been resected. The top jaw shown in FIG. 6 is provided with an engaging means for engaging with the master jaw, and a width B of an installation portion for assembling the master jaw is provided by removing a part of the cone . For this purpose, the master jaw is guided using the width B of the top jaw assembly.
After insertion into the width A of the portion, the wedge-shaped meshing surface centered on the axis of the cone of the top jaw is rotated as a slide surface in a direction parallel to the body surface to detach and attach the jaw. shape that was formed in a conical shape, and is obtained without a permit be engaged with a minimum clearance of the engagement means of the cone can be rotated and moved by providing the embedded part to jaw. If only the rotational movement of the top jaw is controlled based on the shape of the cone thus formed, the positional accuracy of the body in the axial direction and the radial direction can be secured by itself, and the positioning of the top jaw can be performed accurately and accurately. Also, it is possible to change the grasping surface of the top jaw once incorporated. In order to change the grasping surface , the top jaw only has to be rotated by an arbitrary angle. It is not necessary to always remove the jaw completely from the master jaw. As described above, the idea of providing a built-in portion in the engagement means of the jaw, and further rotating and moving the top jaw to attach it to the master jaw is novel, and is particularly effective in changing the setup of the top jaw.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the chuck according to the present invention will be described below in detail with reference to FIGS.

FIG. 1 is a longitudinal sectional view of a chuck according to the present invention, and shows a plunger 2 which slides in the axial direction (the left-right direction in FIG. 1) around the center of a substantially cylindrical body 1.
And a plurality of master jaws 3 slidably moving outward and inward in the radial direction of the body 1 by a wedge action in conjunction with the plunger 2, and each of the master jaws 3 has a wedge-like shape. The engaging portion 4 (engaging means) is formed as a convex portion, the clamp stand 5 and the positioning pin 6 are disposed in the axial direction, and the clamp bolt 15 and the notch pin 19 are inserted from the outside in the radial direction. A screw 45 is provided in the circumferential direction of the body so as to be continuous with the detent groove 40 of the clamp stand 5.

[0008] As shown in FIG.
It is formed in a substantially cylindrical shape, and is urged and inserted axially forward (to the right in FIG. 3) by a spring 8 into a shaft hole 7 formed in a substantially central portion of the master jaw 3 in an axial direction. On the front end side of the clamp stand 5, a nail mounting portion 10 is formed via a small diameter portion 9. The claw mounting portion 10 is formed with a shaved portion 11 in which two circumferential portions of a disk are cut away to face each other, and the claw mounting portion 10 is rotated so that the shaved portion 11 is assembled in a direction parallel to the sliding movement direction of the master jaw 3. A stop groove 40 is provided to project forward of the master jaw 3. Also, on the rear side of the clamp stand 5, FIG.
The wedge surface 13 of the clamper 12 engages with the clamper 12 shown in FIG.

The clamper 12 has a substantially cylindrical shape, and has an arc-shaped wedge surface 13 on one end surface. A clamp bolt 15 is screwed on the outside of the clamper 12 to the master jaw 3.
Of the clamper 12 by turning the
Press inward.

The locking means 50 comprises a positioning pin 6, a spring 18 and a notch pin 19 as shown in FIG. 4, and the positioning pin 6 is formed in a columnar shape.
A spring 18 urges the master jaw 3 axially forward into an axial hole 17 formed in the axial direction on the outer side of the master jaw 3 and is inserted. The front end of the positioning pin 6 is formed in a conical shape, and an axially inclined groove 20 that engages with the notch pin 19 is engraved at the rear. Notch pin 19
Is formed in a stepped substantially cylindrical shape, is incorporated into a hole 21 formed from the outside in the radial direction of the master jaw 3, and has a small screw 2.
2 prevents slippage.

The projection of the wedge-shaped meshing portion 4 (engaging means)
A part of the engaging means is cut off by the width A of the guide portion centering on the shaft hole 7 projecting from the surface 23 of the body and in front of the master jaw 3 shown in FIG.
A claw mounting surface 41 is provided on a protruding front end surface formed as a part of the formed cone. The wedge-shaped meshing surfaces 24a and 24b (the wedge-shaped meshing surfaces 24a and 24b are combined into 24), which are shown in detail in the cross-sectional view of FIG. The gap between the wedge-shaped meshing surfaces 29a and 29b of the top jaw shown in FIG. 6 is 0.02 mm. Further, in a part of the cone of the wedge-shaped meshing portion 4 in FIG. 5, the minimum radius R of the center of the shaft hole 7 into which the clamp stand 5 is fitted is の of the guide width A of the master jaw. Has been made larger.

The top jaw 25 incorporated in the master jaw 3 formed as described above has a structure as shown in FIG.
A grasping surface 31 and a grasping surface 32 for grasping a workpiece are provided at both ends in the vertical direction, and a substantially trapezoidal cut section in the axial direction that is opened rearward is formed at a rear portion. A nail mounting hole 28 that is larger than the hollow portion is formed in the mounting surface 33 serving as the bottom surface through the oval hollow portion 27.

On the mounting surface 33 of the opening 26, two positioning holes 34 are provided at positions 180.degree. Symmetric with respect to the claw mounting holes 28, and a guide groove 35 including the positioning holes 34 is formed. Have been. In the vertical direction of the opening 26, an arc-shaped wedge-shaped engaging portion 2 centered on the hole center of the claw mounting hole 28.
9 (engaging means) is formed so as to form a concave portion, and wedge-shaped meshing surfaces 29a and 29b are provided in a conical shape on the opposing inner surfaces.

Further, a wedge-shaped meshing portion 29 (engaging means)
In the recessed portion, an installation part 30 which is partially removed in the radial direction with the nail mounting hole 28 as the center of distribution is provided with a radial width dimension B. Width B of this built-in part 30
Is set to be larger than the width A of the guide portion of the master jaw 3.

Next, the operation of this embodiment will be described. To attach the top jaw 25 to the master jaw 3, the width A of the guide portion of the master jaw 3 is shifted by 90 ° with respect to the radial direction of the master jaw 3 from the front of the body in the axial direction. of Rutotomoni engaged from the axial direction of the cone so as to straddle the width dimension B of the embedded portion, passes corresponding to cutting penetration point 11 of the claw mounting part 10 which protrudes from the master key 3 in the oval hollow section 27 Then, the nail mounting portion 10 is inserted into the nail mounting hole 28. At this time, the positioning pin 6 is set in the guide groove 35 of the top jaw 25.
Is pushed into the master jaw, and the top jaw 25 is rotated by 90 ° about the clamp stand 5 so that the positioning pin 6 urged by the spring 18 is fitted into the positioning hole 34, and the top jaw 25 is moved.
Is stopped from rotating with respect to the master jaw 3, and the claw mounting portion 10 of the clamp stand and the claw mounting hole 28 of the top jaw engage with each other.

By tightening a clamp bolt provided outside the master jaw 3, the clamper 12
The clamp stand 5 is moved rearward in the axial direction via the claw device 10, and the mounting surface 33 of the top jaw 25 is
The master jaw 3 is completely seated on the claw mounting surface 41, and the mounting is completed.

The positioning pins are used to prevent the top jaw from scattering when the chuck is rotated after the top jaw is attached without grasping the workpiece. When the workpiece is grasped by the top jaw 3 attached in this manner, the wedge-shaped meshing portion 4 of the master jaw 3 is grasped.
And the wedge-shaped meshing portion 29 of the top jaw 25, the top jaw 3 can be firmly engaged with the master jaw 3 in the axial direction and the radial direction. Further, the wedge-shaped meshing surfaces for grasping the inner diameter and the outer diameter are shared by 24a of the master jaw 3 and 29a of the top jaw 25 for grasping the inner diameter, and 24b of the master jaw 3 and 29b of the top jaw 25 for grasping the outer diameter. Will be done.

On the other hand, the top jaw 25 is connected to the master jaw 3
To remove the top jaw 25 , first loosen the clamp bolt 15 by about a half turn to release the seating of the top jaw 25, and then push the notch pin 19 so that the positioning pin 6 comes out of the positioning hole 34, and the top jaw 25 becomes wedge-shaped Surface (24a, 24b, 29a, 29b) as a slide surface so as to be freely rotatable, and the width of the installation portion of the top jaw
By matching the width A of the guide part of B with the master jaw
And can be easily removed. By the way, different dimensions
The change of the grasping surface 31 for grasping the workpiece
As with removing the top jaw 25, the top jaw 25
After rotating the top jaw 25 by 180 °, a new grasping surface 32 can be secured. Thereafter, if the clamp bolt 15 is tightened, the replacement is completed.

As described above, according to the present embodiment, the gripping surface of the top jaw 25 according to the diameter of the workpiece is a chuck jaw having three functions of the seating means, the locking means, and the engaging means. When replacing the top jaw 25, a new grasping surface can be obtained by inverting the top jaw 25 without completely removing it.

Further, by appropriately providing three or four positioning holes for the top jaw, one top jaw can provide a large number of gripping surfaces. As a result, the top jaw 25 can be stably mounted and the grasping surface can be quickly replaced. In the present embodiment, the wedge action portion of the master jaw and the plunger is described as being provided inward and rearward of the master jaw, but may be provided at the center in the radial direction, which was previously filed by the present applicant. Further, a structure not using the wedge action, specifically, a lever shape or another structure may be used.

FIG. 9 shows another embodiment in which the top jaw is inserted into the master jaw from the radial direction of the body. The oval hollow portion 127 and the claw mounting hole 128 of the top jaw 125 have gripping surfaces 131 and 132. Are opened in a direction perpendicular to.

FIG. 10 shows a top jaw integrated with a clamp stand which is a part of the seating means. The master jaw 225 is provided with an axial hole of the master jaw from the front in the axial direction of the body similarly to the first embodiment. 7 is inserted. At the time of insertion, the clamper 12 needs to be sufficiently moved outward in the radial direction so as not to enter the shaft hole 7. To this end, the clamper is engaged with the clamp bolt and is adapted to follow the radial movement of the clamp bolt.

FIG. 11 shows a top jaw in which the number of gripping surfaces is increased. This top jaw 325 is formed in a substantially columnar shape and has a large number of gripping surfaces 331, 332, 333 in front thereof. At the part where the surface is not formed,
0 is provided in one place. For many gripping surfaces,
The concave portion of the wedge-shaped meshing portion 329a has a width B of the built-in portion 330.
Except for the portion 3, the arc is formed.
4 are provided as many as the number of grasping surfaces.

FIG. 12 shows a master jaw 303 in which the top jaw 325 of FIG. 11 is incorporated. The master jaw 303 has a wedge-shaped meshing portion 304 formed only inward in the radial direction for exclusive use in grasping the outer diameter.
The wedge-shaped meshing surface 324b is formed as one convex portion. In order to incorporate this, the top jaw 325 is inserted from the front in the axial direction with the width B3 of the installation portion of the top jaw being equal to the width A3 of the master jaw guide. At this time, as in the first embodiment, the claw mounting portion 10 of the clamp stand is inserted into the claw mounting hole 28 and the top jaw 325 is rotated, so that the positioning pin 6 is turned into the positioning hole 34.
And is positioned. Thereafter, similarly to the first embodiment, the top jaw 325 is completely replaced with the master jaw 3.
03 is attached.

It should be noted that the top jaw shown in FIG.
The master jaw shown in FIG. 12 can be formed integrally with a clamp stand as shown in FIG. 0, and the master jaw shown in FIG. Thus, a master jaw dedicated to grasping the inner diameter can be provided.

[0026]

According to the present invention, the mounting and dismounting of the top jaw or the change of the grasping surface can be instantaneously performed by the above-described steps. Further, it is possible to provide a large number of grasping surfaces on the jaw, and one top jaw can deal with various types of workpieces. In addition, the engagement means requires only the minimum clearance that can be rotated, the position accuracy of the top jaw is dramatically improved, and the wedge action effect is achieved by fitting the cone when grasping the workpiece.
As a result, the lifting of the top jaw in the chuck axial direction
Can be prevented and the grasping accuracy can be improved.
It plays a significant role.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a chuck according to the present invention.

FIG. 2 is a front view of the chuck.

FIG. 3 is a vertical view of a jaw portion.

FIG. 4 is a partial cross-sectional view of the master jaw portion YY of FIG. 2 with the top jaw removed.

FIG. 5 is a perspective view of a master jaw.

FIG. 6 is a perspective view of a top jaw.

FIG. 7 is a perspective view of a clamp stand.

FIG. 8 is a perspective view of a clamper.

FIG. 9 is a perspective view of a top jaw showing another embodiment.

FIG. 10 is a perspective view of a top jaw showing another embodiment.

FIG. 11 is a perspective view of a top jaw showing another embodiment.

FIG. 12 is a perspective view of a master jaw showing another embodiment.

[Explanation of symbols]

· · · · Master jaw 4, 29, 304, 329 · · · Engaging means (wedge-shaped meshing portion) 5 · · · Seating means (clamp stand) 25, 125, 225, 325 ... · Top jaw 50 ··· Locking means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23B 31/16

Claims (3)

(57) [Claims] 1. A master jaw and a top jaw engaged with the master jaw are provided with a circle at a portion where both are engaged.
An engaging means comprising a convex part and a concave part formed from a part of the cone is provided.
A built-in portion is formed by removing a part of the cone to a width B, and the convex portion has a conical portion for guiding the width B of the built-in portion of the concave portion .
Guide portions formed by cutting both sides in the width A is formed, and both
When attaching and detaching the top jaw using the top jaw and the master jaw having a width of B> A, the guide is used.
Top jaw width A parts in the chuck, characterized in that removing or inserting a top jaw forms a step and a top jaw to insert the width B of the embedded portion and the step you rotational movement relative to the axis of the cone How to put on and take off . 2. The width A of the assembly part is inserted into the width A of the guide part.
In the step of inserting the top jaw into the axial center of the cone
2. The chuck according to claim 1, wherein
How to attach and detach the top jaw in the field. 3. The width A of the assembly portion is inserted into the width A of the guide portion.
In the step of inserting the top jaw in the radius direction of the cone
2. The chuck according to claim 1, wherein
How to attach and detach the top jaw in the field.