JPH0144441B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chuck device, and more particularly to a chuck device having a pawl shifting mechanism.

In conventional machine tools, in order to grip workpieces of various sizes with the same chuck that does not have a shift function, the chuck must have a large opening, resulting in a complicated and large chuck structure. It was hot. In addition, replacing the claws according to the diameter of the work requires time and is difficult to automate.

The present invention was made in view of the above circumstances, and it is possible to automatically change the mounting position on the chuck under the numerical control of a machine tool, thereby making it safe without complicating or increasing the size of the chuck. The purpose of the present invention is to provide a device that can accommodate a wide range of workpiece diameters, is capable of not only externally tightening the chuck, but also internally tightening, and has a claw shifting function.

Embodiments of the present invention will be described below based on the drawings. Fig. 1 is a sectional view showing the main parts of a numerically controlled machine tool used to carry out the method of the present invention, Fig. 2 is a cross-sectional view taken from Fig. 1, and Fig. 3 is a partially enlarged sectional view of Fig. 1. It is a diagram. 1 is a headstock, 2 is a main shaft rotatably supported by the headstock 1, and 3 represents the entire three-jaw chuck attached to the main shaft end of the main shaft 2. The structure of the three-pronged chuck 3 is as follows. An adapter 4 and a chuck body 5 are fixed to the main shaft 2 with bolts 6 and 7. Through holes 4a and 5a are provided in the center of the adapter 4 and the chuck body 5 so as to be concentric with the axis of the main shaft 2. A holding member 8 is slidably fitted into the through holes 4a, 5a. A threaded portion 9a of a drawbar 9 is screwed into a threaded portion 8a provided at the rear of the holding member 8, and a hydraulic cylinder (not shown) is provided at the rear of the drawbar 9. Therefore, when the hydraulic cylinder is operated by the control device of the machine tool, the holding member 8 moves back and forth.

In the adapter 4, grooves 4b with stepped portions 4c are formed at three equal intervals on the circumference, corresponding to the three claws, so as to open into the through holes 4a. The groove 4b of the adapter 4
A lever 11 is swingably supported inside by a pin 10 provided in a direction perpendicular to the radial direction of the chuck 3. The lever 11 consists of a rod portion 11a extending approximately in the radial direction of the chuck 3 and a rod portion 11b extending approximately in the axial direction. One of the rod portions 11a fits into the hole 8b such that the bulge provided at its tip is sandwiched between the front and rear walls of the hole 8b formed on the outer surface of the holding member 8.

Further, a notch 5b is formed in the chuck body 5 so as to be continuous with the stepped portion 4c of the adapter 4 and form an integral space within the chuck 3. The notch 5b of the chuck body 5 and the stepped portion 4c of the adapter 4 restrict the movement of the chuck 3 in a direction perpendicular to the radial direction and in the axial direction, and the block 12 is movable only in the radial direction. is charged. The other rod portion 11b of the lever 11 fits into the hole 12a in such a way that the bulge provided at its tip is held between the upper and lower wall surfaces of the hole 12a bored in the block 12.
Therefore, when the holding member 8 reciprocates, the block 12 moves in the radial direction of the chuck 3 through the swinging of the lever 11.

A shift member 13, which is a locking member, is mounted in the notch 5b of the chuck body 5 in such a manner that its movement is restricted in the axial direction of the chuck 3, and it is movable in the radial direction and in the direction orthogonal to the radial direction. entered. The shift member 13 has a protrusion 13a and a groove 13b in a direction perpendicular to the radial direction of the chuck 3. The protrusion 13a of the shift member 13 is a groove 12 provided in the block 12 in a direction perpendicular to the radial direction of the chuck 3.
b, and the groove 13b of the shift member 13
A protrusion 12c provided in the block 12 in a direction perpendicular to the radial direction of the chuck 3 engages with the block 12. Therefore, as the block 12 moves in the radial direction of the chuck 3, the shift member 13 also moves in the radial direction, and is also movable in a direction perpendicular to the radial direction. 13
serves as a guide when moving in a direction perpendicular to the radial direction.

A through hole 5c is formed in the chuck body 5 from its outer circumference to the inner surface facing the shift member 13. A rotating body 14, which is a transmission member, is rotatably inserted into the through hole 5c. The rotating body 14 has a pin 15 that engages in an annular groove 14 provided on its outer periphery.
It is prevented from falling off. An eccentric pin 14b is implanted at the end of the rotating body 14 facing the shift member 13, and the eccentric pin 14b engages with a groove 13c as a cam surface formed in the shift member 13. A driver insertion hole 14c is provided in the end surface of the rotating body 14 facing outside the chuck 3. As an operating means corresponding to the driver insertion hole 14c, a fluid- or electrically driven driver 1 is operated as an operating means to rotate by a predetermined angle by a control device of the machine tool.
6 is provided on the headstock 1 or the turret 17. Therefore, the rotating body 14 is rotated by the driver 16.
When the eccentric pin 14b is rotated 180 degrees and displaced from the position shown by the solid line in FIG. 2 to the position shown by the imaginary line, the shift member 13 moves the chuck 3 from the position shown by the solid line in FIG. 2 to the position shown by the imaginary line. move in a direction perpendicular to the radial direction. 18 is spring 1
Rotating body 1 pressed toward rotating body 14 by 9
This is a ball for positioning No. 4. The ball 18
When the eccentric pin 14b of the rotating body 14 is in the position shown by the solid line in FIG.

The shift member 13 has straight teeth 13d. 20 is a straight tooth 20 that meshes with the straight tooth 13d of the shift member 13.
A base jaw 21 is a soft jaw fixed to the base jaw 20 with bolts 22 and 23. The base jaw 20 has protrusions 20b, 20b provided on both sides of the chuck body 5.
It fits into the guide grooves 5d and 5d of the chuck 3.
is held movably in the radial direction. Therefore, when the shift member 13 moves in the radial direction of the chuck 3, the soft jaw 21 performs expansion and contraction movements.

The relationship between the lengths of the straight teeth 13d of the shift member 13 and the straight teeth 20a of the base jaw 20 and the amount by which the shift member 13 moves in a direction perpendicular to the radial direction of the chuck 3 due to the rotation of the rotating body 14 is as follows.
3 is in the position shown by the solid line in Fig. 2, both straight teeth 1
3d and 20a are completely engaged with each other, and when the shift member 13 is in the position shown by the imaginary line in FIG. 2, both straight teeth 13d and 20a are disengaged.
Therefore, when the shift member 13 is in the position shown by the solid line in FIG.
It becomes a locking member for. When the shift member 13 is in the position shown by the imaginary line in FIG. 2, the base jaw 20 can be freely inserted into and removed from the chuck 3 in the radial direction. In this state, in order to move the base gear 20 in the radial direction of the chuck 3, the tool rest 17
is provided with an engaging piece 24 which is a pawl moving member, and the base jaw 20 is provided with a groove 20c which is an engaging part corresponding to the engaging piece 24. When this engagement piece 24 is engaged with the groove 20c of the base jaw 20 and the tool post is moved, the base jaw also moves in two directions, either toward the outer circumference or toward the inner circumference of the chuck. Therefore, the chuck can be used for both external and internal tightening.

In the chuck 3 of the numerically controlled machine tool whose main parts have been explained above, the soft jaw 21 expands and contracts by moving the drawbar 9 in the axial direction, and the base jaw 20 is locked by rotating the rotating body 14. is released. Therefore, the soft jaw 21 can be positioned using the machine tool according to the procedure described below. Rotate the main shaft 2 without using the chuck 3,
The driver insertion hole 14c of the rotating body 14 is located at a position corresponding to the driver 16. Any known method may be used for indexing the spindle.
For example, counter processing from a reference position may be used, or mechanical pins or the like may be used. Next, move the tool rest 17 and remove the groove 20c of the base jyo 20.
The engaging piece 24 is engaged with. In this state, insert the driver 16 into the driver insertion hole 14c of the rotating body 14.
The shift member 13 is moved to the position shown by the imaginary line in FIG. 2, that is, to the position where the base jaw 20 is released. Next, move the tool rest 17 to the straight teeth 13 in the radial direction of the chuck 3.
It is moved by an integral multiple of the pitch of a and 20a.
By rotating the driver 16 by 180 degrees, the shift member 13 is returned to the position shown by the solid line in FIG. By moving the tool post 17, the engagement piece 24 is inserted into the groove 2 of the base jyo 20.
Make it dissociate from 0c. By the above procedure, the base jaw 20 and the soft jaw 21 are moved by a predetermined amount in the radial direction, and are again in a chuckable state.

Since the chuck device of the present invention having a pawl shifting function is constructed as described above, it produces the following effects. That is, when the locking member and the pawl are disengaged, the pawl can move freely in the radial direction of the chuck. Therefore, when the pawl moving member attached to the tool post is engaged with the pawl engaging member to operate the tool post, the pawl moves in two directions, outward and inward in the radial direction of the chuck. Can be used for external tightening of workpieces,
It is now possible to use it for both internal tightening.

The amount of movement of the chuck opening/closing drive mechanism in the direction of the main shaft axis and the amount of movement of the pawl in the radial direction can be made approximately 1:1. Therefore, it is possible to increase the amount of movement of the claw without increasing the outer diameter of the chuck, and it has become possible to flexibly accommodate a wide range of outer diameters of workpieces.

When the locking member and the pawl are disengaged, the pawl can move freely in the radial direction of the chuck. Therefore,
The amount of movement of the jaws can be determined according to the diameter of the work to be chucked, and chucking is possible with minimal movement of the jaws, the number of times the jaw shift function is used can be reduced, and machining efficiency is improved.

To move the pawl, the chuck stops rotating and engages the pawl with the pawl moving member to operate the tool post, so the pawl and the pawl moving member are not damaged and is very safe. It became a thing.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a sectional view, FIG. 2 is a cross-sectional view taken from FIG. 1, and FIG. 3 is a partially enlarged sectional view of FIG. 1. 1...Headstock, 2...Main shaft, 3...Chuck, 13...Shift member (locking member), 13
c... Concave groove, 14... Rotating body (transmission member), 14
b...Eccentric pin, 16...Driver (operating means), 17...Turret, 20...Base jaw,
20c...Groove, 21...Soft Jiyo, 24...
Engagement piece (claw moving member).

Claims (1)

[Claims] 1 A chuck provided on the main shaft of a turning machine tool; a pawl provided on the chuck that moves while being guided in the chuck radial direction and has an engaging portion at one end; a locking member that is movable and engages with and disengages from the pawl; a transmission member that is rotatably provided on the chuck and engages with the locking member to move the locking member in a rotational direction; an operating means provided on the outside that engages with the transmission member and rotates the transmission member when the chuck is indexed to a predetermined position; and control means that can freely move forward and backward into a position facing the claw of the chuck. When the transmission member is actuated by the operation of the operating means provided on the tool rest arranged in a manner such that the locking member moves in the rotational direction and separates from the pawl, the locking member engages with the engaging portion of the pawl; A pawl moving member that positions and moves the pawl in the radial direction of the chuck in a freely forward and backward manner by the operation of the tool rest, a block that engages with the locking member and is movable while being guided in the radial direction, and a pawl that moves the block. A chuck device having a pawl shifting function, characterized by comprising an opening/closing drive mechanism.