JPH06155209A - Continuously variably clamping jig for any bore - Google Patents

Abstract

PURPOSE:To provide a continuously variably clamping jig for any bore in which works having large difference in bores can be clamped without changing the jig. CONSTITUTION:This continuously variably clamping jig for any bore 10 is provided with a housing 11 which is provided with step parts 11a, 11b and a plurality of openings 11c and fitting holes 11d in the radial direction, firmly fixed to a supporting body 20, and to the outer circumference, of which works W1, W2 are fitted or detached a plurality of pins 12 which are fitted in the respective fitting holes 11d capably of projecting and retreating and energized inward by means of a first spring S1, a draw bar 13 which is fitted in the inner hole of the housing 11 and provided with a taper part 13a engaged with the inner ends of the respective pins 12, and a case 14 which is fitted into the inner hole of the extreme end part of the housing 11 and energized to the extreme end of the draw bar 13 by means of a second spring S2. Further, a plurality of claws 15 which are assembled to the case 14, energized to the outside by means of a third spring S3, and projected or retracted through the openings 11c according to the movement of the case 14 in the axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal diameter stepless clamping jig for clamping various workpieces having different internal diameters in a machine tool.

[0002]

2. Description of the Related Art A conventional inner diameter stepless clamping jig uses a collet (a ring that has a large number of axial slits in the circumferential direction and can be expanded in diameter). The work is clamped by being mounted and expanded by an expander (expansion member).

[0003]

By the way, in the inner diameter stepless clamping jig using the collet, since the diameter expansion deformation of the collet is utilized, the difference in the inner diameter which can be clamped by the same collet is usually 0. It is about 3 mm, and when clamping a work with a large difference in inner diameter, it is necessary to change to a clamp jig that uses a collet with a different basic diameter, which makes usability poor. The present invention has been made to solve the above-described problem, and an object thereof is to provide an inner diameter stepless clamping jig capable of clamping a work having a large inner diameter difference without changing the jig.

[0004]

In order to achieve the above object, in the present invention, the inner diameter stepless clamping jig is a stepped cylinder having a step on the outer circumference in the circumferential direction at the tip. It has a plurality of openings at equal intervals and a plurality of radial mounting holes at equal intervals in the circumferential direction in the middle, and a cylindrical work is fixed to the support of the machine tool at the base end on the outer circumference. A housing that is axially attached and detached from the tip end side, a plurality of pins that are assembled in the mounting holes of the housing so as to be retractable in the radial direction, and are biased inward by a first spring, and an inner hole of the housing And a draw bar having a tapered portion that is axially movable so as to engage with the inner end of each pin on the tip side of each pin, and an axially movable assembly in a distal end inner hole of the housing. And is arranged coaxially with the drawbar and is A case is urged toward the tip of the draw bar by a ring, and a case is attached to the case so as to be rotatable in the radial direction at one end and is urged outward by a third spring so that the case is not in contact with the draw bar. When engaged, the other end of the housing projects through the opening of the housing to the outside of the housing by a predetermined amount, and the case engages the draw bar and is pushed forward against the second spring. A plurality of claws that are engaged and housed in the housing are provided.

[0005]

In the inner diameter stepless clamp jig according to the present invention, when the case is engaged with the draw bar and is pushed forward against the second spring, the claws engage with the housing and the housing. Since it is housed inside, the cylindrical work can be attached to and detached from the tip side of the outer circumference of the housing. Further, when the draw bar is pulled axially toward the base end side of the housing with the cylindrical work fitted in the outer periphery of the housing, the case is released from the engagement with the draw bar.
It is pushed in the axial direction by the spring and each claw is radially outwardly rotated by the third spring so that the other end projects out of the housing by a predetermined amount and engages with the end of the work, and the taper of the draw bar. Each pin is pushed outward in the radial direction against the first spring, and engages with the inner diameter of the work at the outer end. Therefore, the work is clamped in the axial direction by the claws and the stepped portion of the housing, and is radially held by the pins, and is firmly clamped in the centered state.

When the draw bar is pushed axially toward the tip of the housing in such a clamped state, the draw bar engages with the case and pushes the case in the axial direction against the second spring. Moves away from the end of the work and engages with the housing to rotate radially inward against the third spring, the other end is housed in the housing, and the tapered portion of the drawbar separates from each pin. , The pins are pushed inward in the radial direction by the first spring to separate from the inner diameter of the work. Therefore, the work is released from the axial holding by each claw and the stepped portion of the housing and released from the radial holding by each pin, and the clamp is released.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a state in which a work W1 having a long axial length and a small inner diameter and a work W2 having a short axial length and a large inner diameter are clamped by using the inner diameter stepless clamping jig 10 according to the present invention. The jig 10 has a housing 11, a pin 12, a draw bar 13, a case 14, and a claw 15 attached to the housing 11 as main constituent members. The housing 11 has stepped portions 11a and 11b on the outer circumference and is fixed to the rotary support body 20 of the machine tool by bolts at the large-diameter base end portion on the left side in the drawing, with a stepped cylinder (in this embodiment, the main body 11A. I adopted a stepped sleeve 11B combined with a bolt,
It is also possible to employ an integrally formed one), and three (or four or more) openings 11c are arranged at equal intervals in the circumferential direction at the small diameter tip part on the right side in the drawing. Further, three (or more than four) radial mounting holes 11d are formed in the small-diameter intermediate portion at equal intervals in the circumferential direction, and cylindrical works W1 and W2 are formed on the outer periphery from the tip side. It is designed to be attached and detached in the axial direction.

The pin 12 is attached to each mounting hole 1 of the housing 11.
The first spring S1 is attached to the arm-shaped flange of the pin 12 at one end and the other end at the other end. It is locked to a stopper 16 fixed to the housing 11. The draw bar 13 is assembled in the inner hole of the housing 11 so as to be movable in the axial direction, and is reciprocally moved by a double-acting hydraulic cylinder connected to the left end (not shown). Each pin 12 has a tapered portion 13a that engages with the inner end of the pin. The draw bar 13 is restricted from rotating by bolts attached to the housing 11.

The case 14 is attached to the inner hole of the front end portion of the housing 11 so as to be movable in the axial direction.
3, and is urged toward the tip of the drawbar 13 by the second spring S2. Second
The spring S2 has one end locked to the tip of the case 14 and the other end locked to the cap 17 fixed to the housing 11. Each of the pawls 15 is attached to a notch provided in the case 14 at one end thereof via a support pin 18 so as to be rotatable in the radial direction, and is biased outward by a third spring S3. The spring S3 is locked to the case 14 at one end and to the claw 15 at the other end. Then, each nail 15
When the case 14 is not engaged with the drawbar 13, the other end projects a predetermined amount out of the housing 11 through the opening 11c of the housing, and the case 14 engages the drawbar 13 and resists the second spring S2. When it is pushed forward, it engages with the housing 11 at the front end of the opening 11c, rotates inward, and is housed in the housing 11.

In this embodiment constructed as described above, when the case 14 is engaged with the draw bar 13 and is pushed forward against the second spring S2, each pawl 15 is pressed.
Is engaged with the housing 11 and is housed in the housing 11, so that the cylindrical work W1 or W2 can be attached to and detached from the distal end side of the outer periphery of the housing 11. Further, when the hydraulic cylinder is operated with the cylindrical work W1 or W2 inserted into the outer periphery of the housing 11 and the draw bar 13 is pulled in the axial direction toward the base end side of the housing 11, the case 14 is opened as shown in the figure. The engagement with the drawbar 13 is released, and the second spring S2 pushes it axially, and each claw 15 is rotated radially outward by the third spring S3 so that the other end of the claw 15 is moved outside the housing 11 by a predetermined amount. It projects and engages with the end of the work W1 or W2, and each pin 12 is pushed radially outward by the tapered portion 13a of the drawbar 13 and engages with the inner diameter of the work W1 or W2 at the outer end. . Therefore, the work W1 or W2 is attached to each nail 1.
5 and the housing step portion 11a or 11b are sandwiched in the axial direction and radially retained by the pins 12, and firmly clamped in the centered state.

When the hydraulic cylinder is actuated in such a clamped state to push the draw bar 13 axially toward the tip of the housing 11, the draw bar 13 is moved to the case 14.
And the case 14 is pushed in the axial direction against the second spring S2 by engaging with the workpiece W1 or W2.
Away from the end portion of the housing 11 and engages with the housing 11 to rotate inward in the radial direction against the third spring S3, the other end portion is housed in the housing 11, and the draw bar 13
Since the tapered portion 13a of each of the pins 12 separates from each pin 12, each pin 12 is pushed radially inward by the first spring S1 and separates from the inner diameter of the work W1 or W2. Therefore, the workpiece W1 or W2 is released from the axial holding by the claw 15 and the stepped portion 11a or 11b of the housing and released from the radial holding by the pins 12, and the clamp is released.

[0012]

In summary, according to the present invention, the work which is removably mounted on the outer periphery of the housing is axially clamped by the claws mounted on the case and the stepped portion of the housing, and the draw bar is tapered. Since it is clamped so as to be held in the radial direction by each pin that is pushed outward in the radial direction, the difference in inner diameter is within the radial movement amount of each pin due to the tapered portion of the drawbar. All workpieces can be clamped.By setting the amount of radial movement of each pin by the taper part of the drawbar, workpieces with a large difference in inner diameter can be clamped accurately without changing the jig, thus reducing the working time. It can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of an inner diameter stepless clamping jig according to the present invention.

[Explanation of symbols]

10 ... Inner diameter stepless clamp jig, 11 ... Housing, 1
1a, 11b ... Step, 11c ... Opening, 11d ... Radial mounting hole, 12 ... Pin, 13 ... Drawbar, 13a ... Tapered part, 14 ... Case, 15 ... Claw, S1 ... 1st spring,
S2 ... second spring, S3 ... third spring, W1,
W2 ... work.

Claims (1)

[Claims] 1. A stepped cylinder having a step on the outer circumference, a plurality of openings at equal intervals in the circumferential direction at the tip end, and a plurality of radial mounting holes at equal intervals in the circumferential direction at an intermediate portion. And a housing that is fixed to the support of the machine tool at the base end and has a cylindrical work that is axially attached to and detached from the tip end side of the outer circumference, and is assembled in the mounting holes of this housing so that it can project and retract in the radial direction. First
A plurality of pins that are biased inward by springs, and a taper portion that is assembled in the inner hole of the housing so as to be movable in the axial direction and that engages with the inner ends of the pins are located on the tip side of the pins. A drawbar having the case, a case that is movably assembled in the inner hole of the front end portion of the housing, is arranged coaxially with the drawbar, and is urged toward the front end of the drawbar by a second spring; When the case is disengaged rotatably in the radial direction and is urged outward by a third spring so that the case is not engaged with the drawbar, the other end passes through the opening of the housing to a predetermined amount outside the housing. When the case protrudes and the case is pushed forward against the second spring by engaging with the draw bar, the case is accommodated in the housing by engaging with the housing. Inner diameter Mudanto clamp jig having a number of nails.