JP2955542B2 - Work support device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a support device for a work to be machined, and more particularly, to a work support device which holds the work properly and minimizes the distortion of the work.

[0002]

2. Description of the Related Art Conventionally, as a supporting device for a workpiece to be machined, as disclosed in Japanese Patent Application Laid-Open No. 5-104312,
Fluid supplied from a tube inserted through the axis of the spindle is fed by switching to the front or rear side of the piston in the hollow chamber in the base via the branch passage of the base rotating with the spindle, and the piston is moved. A plurality of work gripping claws disposed on the front surface of the diaphragm are expanded or contracted (reduced) as the piston moves.

[0003]

According to the work supporting apparatus having the above-mentioned structure, a portion of the work close to the processing portion is grasped (grabbed), and the work is stabilized during the processing. , The work is deformed.

[0004] Then, the deformed work is machined, and the work removed after the machining has an irregular machining accuracy (as the work returns to the deformed state).

[0005] If the work is softly gripped so as not to be deformed, the work cannot be machined.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a work supporting apparatus which guarantees a gripping force suitable for machining and prevents deformation of a machined portion of the work.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a base rotating with a spindle of a machine tool, a first piston housed in a first hollow chamber provided in the base. , a passageway is provided so as to communicate with either one before and after the first hollow chamber of the first piston, suitably in front of the base with the sliding of the first piston by the supply fluid from the through passage a plurality of gripping claws provided to retract the gripping position via a transmission mechanism having a return force, a collet chuck incorporating a loosely fitted in the recesses facing inward from the front axis of said substrate, said
Centering force on the collet chuck case on the peripheral wall of the recess
And a second piston built in a second hollow chamber provided in the base, and provided so as to communicate before and after the second piston in the second hollow chamber. A work supporting device including a certain fluid supply passage and a coupling mechanism of a universal joint provided so as to advance and retreat the collet of the collet chuck with the slide of the second piston is employed.

[0008]

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

In the embodiment of the present invention, as shown in FIGS. 1 and 2, a first hollow chamber 3 is provided in a base 2 which rotates together with a spindle 1 of a machine tool. , The first piston 4 is incorporated.

Further, the base 1 is provided with a first passage 5 communicating with the rear side of the first piston 4 of the first hollow chamber 3, and when a fluid (air) is pressure-fed from the first passage 5, One piston 4 moves forward.

Further, a plurality of gripping claws 7 are provided on the front surface of the base 2 through a suitable transmission mechanism 6 having a returning force as the first piston 4 advances.

As the transmission mechanism 6 having the above-mentioned restoring force, one end of a U-shaped side spring steel 8 is fixed to the front surface of the base 2 and a gripping claw is attached to the other end of the spring steel 8 as shown in the figure. 7 is fixed (by bolting), the piston shaft 10 of the first piston 4 is passed through the through hole 9 in the center of the front wall of the base 2, and the stepped portion 11 on the outer periphery of the distal end of the piston shaft 10 and the spring steel 8 The end on the end side is engaged.

Then, when the first piston 4 is advanced by feeding the fluid from the first passage 5 to the first hollow chamber 3, the other end of the spring steel 8 engaged with the piston shaft 10 which is advanced together is returned. Since it is pushed back against the force, the gripping claws 7 open.

Of course, when the pumping of the fluid from the first passage 5 is released, the push-back force of the other end of the spring steel 8 by the piston shaft 10 does not act, so that the other end of the spring steel 8 returns and returns. As a result, the gripping claws 7 are closed.

In place of the above-mentioned method, the notch tensile strength of the peripheral edge of the front surface of the substrate 2 is machined in a solution treatment state using, for example, a precipitation hardening alloy as a material, and is heat-aged and hardened to have an appropriate hardness. Fix the periphery of the diaphragm,
A plurality of gripping claws are fixed to the front surface of the diaphragm, and a method in which a piston shaft is fixed to the center of the diaphragm (not shown because it is well known) may be adopted.

A recess 12 is provided inwardly from the front axis of the base 2, and a collet chuck 13 is loosely fitted into the recess 12.

The collet chuck 13 is loosely fitted.
In order to insert the collet chuck 13 outside the case 20
A predetermined gap is provided between the circumference and the inner circumference of the concave portion 12.
Then, a centering force is applied to the case 20 (to the collet chuck 13) by an appropriate pressing member 31.

As shown in FIG. 3, the pressing member 31 has a bottomed cylindrical body 33 having a threaded portion 32 on the outer periphery thereof,
A through hole 34 provided in the center of the bottom wall of the tubular body 33, a pin 36 with a terminal retaining flange 35 penetrated through the through hole 34,
A coil spring 37 fitted into the cylindrical body 33 and a plug 38 screwed into the cylindrical body 33 so as to compress the coil spring 37, and as shown in FIGS. Screw holes 3 provided at equal intervals on the peripheral surface
9 is screwed into the cylindrical body 33 with the end of the plug 38 preceding the end, and the tip of the pin 36 is pressed against the outer peripheral surface of the case 20 of the collet chuck 13 inserted in the recess 12, and the core-centering force is applied to the collet chuck 13. However, a method other than the above, for example, a method of arranging a plurality of elastic O-rings such as rubber may be adopted.

Further, the collet chuck 13 in the base 2
A second hollow chamber 14 is provided at the rear of the second hollow chamber 14, and a second piston 15 incorporated in the second hollow chamber 14 is connected to the first passage 5 communicating with the rear side of the second piston 15 of the second hollow chamber 14.
From the second hollow chamber 14
The piston 15 is retracted by pressure feeding of fluid from the second passage 16 communicating with the front side.

The piston shaft 17 of the second piston 15
Is connected to the collet 19 of the collet chuck 13 via a universal joint connecting mechanism 18, and the collet 19 is pushed out as the second piston 15 advances, and
When the diameter of the collet 19 is released by the tapered surface 21 provided on the outer periphery of the collet chuck 20 and the inner periphery of the collet case 20 of the collet chuck 13, the collet 19 is expanded, and the collet 19 is pulled back and contacted with the retraction of the second piston 15. The collet 19 is closed and closed by the surface portion 21.

As the universal joint 40 of the connecting mechanism 18
In the case shown in FIG. 2, the end of the connection fitting is rotatable via a pin on the piston shaft 17 and the end of the collet 19 via a pin whose axis intersects the pin of the piston shaft 17 at a right angle to the tip of the connection fitting. However, the present invention is not limited to this configuration, and a universal joint having another configuration may be used.

As a means for supplying a fluid to the first passage 5 and the second passage 16, there is a system (not shown) for connecting a tube inserted into a through-hole of the shaft of the spindle 1 via a rotary joint. .

With the above-described structure, the first piston 4 and the second piston 15
To move forward.

As the first piston 4 advances, the gripping pawl 7 mounting side of the spring steel 8 engaged with the piston shaft 10 is pushed back to expand the gripping pawl 7.

Further, since the collet 19 connected to the piston shaft 17 via the connecting mechanism 18 of the universal joint 40 is pushed back with the advance of the second piston 15, the collet 19 whose diameter has been reduced by the tapered surface portion 21 is expanded. Open.

While maintaining this state, as shown in FIG. 1, a large-diameter processed portion a of the article A is placed between the expanded gripping claws 7 and a small-diameter protruding portion a at the center of the back surface of the processed portion a in the expanded collet 19. ′.

Thus, the pumping of the fluid from the first passage 5 is released, and the pumping of the fluid from the second passage 16 is performed.

Since the pushing back of the spring steel 8 is released with the release of the pressure feeding of the fluid, the gripping claw 7 mounting side of the spring steel 8 is returned.

Then, the goods A are moved by the respective gripping claws 7 which are closed and closed.
Of the processed part a.

The holding force of the gripping claws 7 is only the restoring force of the spring steel 8. That is, the processing part a is supported by a soft force that does not cause deformation, and the processing part a is gripped with a minimum distortion.

On the other hand the own with the retraction of the second piston 15
Since the collet 19 is pulled back through the coupling mechanism 18 of the joint 40, the diameter of the collet 19 is gradually reduced by the tapered surface portion 21, and the collet 19 is strongly gripped by the collet 19 as the collet 19 is closed.

Then, the centering of the article A at the reference portion outer diameter (processed portion a) of the article A is performed by the gripping claws 7, the gripping is performed softly without distortion, and the protrusion is strongly gripped by the collet chuck 13.

Further by the gripping claws 7 a machining portion a of the article A,
'When supporting the collet chuck 13, the projecting portion a relative working unit a' protrusion a even if decentered slightly linking machine
The collet chuck 13 swings by the universal joint 40 of the frame 18 and pushes and releases the pressing member 31 on the swinging direction side, so that the collet chuck 13 automatically exerts a centering force.

Note that, as shown in FIG.
When fluid is supplied to the front chamber of the piston 4 from another third passage 51, the first piston 4 is retracted, and strong support by the gripping claws 7 becomes possible.

[0035]

As described above, the work supporting apparatus of the present invention is configured as described above, so that the centering of the article is performed by the gripping claw at the reference portion outer diameter (working portion), and the workpiece is softly gripped without distortion. Collet chuck grips protruding part strongly
Te, it is crazy to machining accuracy eliminate the distortion of the goods of the workpiece
In addition, the collet chuck has a centering function, so the outer diameter (working part) of the reference part of the product is centered by the gripping claw and softly gripped, and the center of the projected part is automatically centered and powerful. There is no loss of gripping function.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a work supporting device according to the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is an enlarged longitudinal side view showing a pressing member.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 spindle 2 base 3 first hollow chamber 4 first piston 5 first passage 6 transmission mechanism 7 gripper 8 spring steel 9 through hole 10 piston shaft 11 step 12 recessed section 13 collet chuck 14 second hollow chamber 15 second piston 16 second passage 17 piston shaft 18 connecting mechanism 19 collet 20 collet case 21 tapered surface portion 31 pressing member 40 universal joint

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-117216 (JP, A) JP-A-7-314221 (JP, A) JP-A 62-35756 (JP, U) 40804 (JP, Y2) 2-24566 (JP, Y2) 7-46408 (JP, Y2) (58) Field surveyed (Int. Cl. ⁶ , DB name) B23Q 3/06 303 B23B 31/20 B23B 31/32

Claims (1)

(57) [Claims] 1. A base rotating with a spindle of a machine tool, a first piston housed in a first hollow chamber provided in the base, and one of front and rear of the first piston in the first hollow chamber. a passage is provided to communicate, provided so as to retreat from the gripping position via a transmission mechanism having an appropriate return force on the front of the base with the sliding of the first piston by the supply fluid from the through passage A plurality of gripping claws; a collet chuck loosely fitted into a concave portion facing inward from the front axis of the base; and the concave portion
Giving the collet chuck case a centripetal force on the peripheral wall of
An appropriate pressing member provided to perform the operation, a second piston incorporated in a second hollow chamber provided in the base,
A work comprising a fluid supply passage provided in front of and behind the second piston of the hollow chamber, and a coupling mechanism of a universal joint provided to advance and retreat the collet of the collet chuck as the second piston slides. Support device.