JPS64242Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a collect chuck used for grasping a workpiece when machining a bar or a secondary workpiece in a machine tool such as a lathe.

[Conventional technology]

Collection chuck is generally JISB6141-1973
The main body is a spring collet of the S-shape, D-shape, or a similar shape as defined above, or a non-standard push-shape, and this collet is combined with a holding member, an operating member, etc.

Conventionally, all of these collet chucks have been used to press or pull the collet housed in a holding member with a spiral/cam system or a fluid pressure cylinder through an actuating tube to move the workpiece. A chuck type that could be tightened and loosened was commonly used.

However, it is generally quite difficult to obtain a strong tightening force with the above-mentioned spiral/cam structure, and in such cases, a hydraulic cylinder operating system has usually been adopted.

[The problem that the idea attempts to solve]

However, in the above-mentioned fluid cylinder operating system, in order to obtain a stronger tightening force in cases such as heavy cutting, a cylinder with a strong pressing force corresponding to this tightening force is used, and this cylinder is used in the machine. It must be installed at the rear of the main shaft via a rotary connector, etc. Here, since the volume and weight of cylinders generally increase in proportion to the pressing force, in order to increase the speed of the main shaft rotation of current machines,
There have been problems in that heat generation due to increased gravity and thrust applied to the rotary connector, and in the case of hydraulic cylinders, various problems can occur due to the excessive rise in oil temperature.

In view of the above, an object of the present invention is to provide a device that can obtain stronger and more uniform tightening force without increasing the volume and weight of the cylinder.

[Means to solve the problem]

In order to achieve the above object, the collect chuck of the present invention is a cylinder having both ends opened in the thick part of the substantially cylindrical sleeve 4, which is made up of a thick wall part at the rear and a thin wall part at the front, with a stepped part 4a formed on the inner circumferential surface. hole 4'
This sleeve 4 is attached to the front of the spindle head 1 of the machine in use via the adapter 2, and a stepped portion 6a opposite to the stepped portion 4a is provided approximately in the center of the outer peripheral surface.
A chucking sleeve 6 having a tapered surface 6b on its front inner circumferential surface is fitted into the sleeve 4, and a tapered surface 9a matching the tapered surface 6b and a head are formed inside the chucking sleeve 6. A collet 9 having a reverse tapered surface 9b is fitted in the
A cap 12 having a tapered surface 12a that abuts the reverse tapered surface 9b is fixed to the front end of the sleeve 4, and an actuation pipe adapter is connected to the front end of an actuation pipe 22 that is disposed inside the spindle head 1 and moves back and forth. A piston receiver 18 is fixed to the sleeve 20, and the piston 16 is fitted into the cylinder hole 4'' with the piston 16 projecting backward, and the rear end of the piston 16 is connected to the piston receiver 18, This stepped portion 4a and the stepped portion 6a of the chucking sleeve 6
A closable oil hole 4'' for guiding oil is provided in the gap between the oil hole 4'' and all gaps communicating with the oil hole 4'' are filled with oil O.

[Effect]

According to the present invention configured as described above, the piston 16 also moves forward as the actuating tube 22 moves forward, and this movement causes the piston 16 to move between the stepped portion 4a of the sleeve 4 and the stepped portion 6a of the chucking sleeve 6, etc. Filled oil O
is compressed, and the chucking sleeve 6 is also moved forward by this pressing force. As the chucking sleeve 6 moves forward, it connects the taper surface 9a of the collet 9 via the tapered surface 6b, and furthermore, as the collet 9 moves forward slightly, it connects the collet 9 via the tapered surface 12a of the cap 12. Reverse tapered surface 9
b is pressed respectively, and thereby the collet 9 is pressed inwardly along the tapered surfaces 9a and 9b, allowing the collet 9 to grip the workpiece more strongly and more uniformly.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in Fig. 1, the spindle head 1 of the machine used has
The adapter 2 of the collector chuck is fitted and fixed via six bolts 3 arranged on a circumference concentric with the axis. On the inner peripheral surface of the right end of this adapter 2,
The left end protrusion of the sleeve 4 is fitted, and 6
It is fixed via equally spaced bolts 5.

A stepped portion 4a is formed on the inner circumferential surface of the sleeve 4, and is divided into a rear (left side) thick walled portion and a front (right side) thin walled portion via this stepped portion 4a.
In this thick portion, six equally spaced cylinder holes 4' are bored on the circumference concentric with the center of the sleeve 4, parallel to the center extension line and open at both ends. Further, a chucking sleeve 6 having a stepped portion 6a opposite to the stepped portion 4a on its outer circumferential surface is slidably inserted into the inner circumferential surface of the sleeve 4.
The annular grooves provided on the small diameter part and large diameter part of the outer periphery of the
An O-ring 7 with a back-up spring for preventing oil leakage and a similar O-ring 8 are installed, respectively.

A tapered surface 6b is formed at the front (right side) of the straight inner circumferential surface of this chucking sleeve 6,
A collector 9 having a tapered surface 9a that matches the tapered surface 6b is fitted inside this, and the collector 9 has a tapered surface 6b of the chucking sleeve 6.
A pin 10 is press-fitted into the vertical groove extending from the outer circumferential surface at right angles to the axis, and the tip of this pin 10 engages with the outer circumferential surface of the collector 9 to maintain a constant position on the circumference. ing.

The collet 9 has a shape and capacity conforming to the JIS standard S type, and is used to grasp the workpiece 11 by inserting it into its bore.

A cap 1 is attached to the front end protrusion of the sleeve 4.
2 is fitted and fixed via six bolts 13 equally spaced on the circumference, and the head of the collector 9 is formed with a reverse tapered surface 9b, and the cap 12 is fitted with the reverse tapered surface 9b. The front end tapered surface 12a is configured so that the cap 12 presses the collector 9 rearward and inward when the front end taper surface 12a contacts.

Further, annular grooves are formed at two adjacent locations on the left end of the thick inner circumferential surface of the sleeve 4, and a collet stopper ring 14 is mounted by being held by a snap ring 14' fitted into the annular groove.

As shown in FIGS. 1 and 3, two oil holes 4'' are drilled at symmetrical positions on the flange of the sleeve 4, extending toward the center, bent at right angles, and passing through the step. The inlet is closed by a plug screw 15.

A piston 16 is fitted into each of the cylinder holes 4' with O-rings 17 with back-up springs on both sides attached to two outer peripheral grooves of the piston 16.
The left end threaded shaft portion 6 fits into six holes equally spaced on the circumference of the side surface of the piston receiver 18, and is fixed by a piston locking nut 19. This piston receiver 18 has its inner circumferential surface fitted with the outer circumferential surface of the small diameter portion of the actuating tube adapter 20, and is fixed by screwing a nut 21 into a threaded portion carved in the right end of the actuating tube adapter 20. .

A female thread is formed on the left end of the actuating pipe adapter 20, and the actuating pipe adapter 2 is inserted through this female thread.
0 is screwed onto the actuating tube 22. This operating tube 2
2 extends through the through hole of the main shaft 1, and its left end is connected via a rotary connector to a piston of a hydraulic cylinder, which is a push/pull device, installed at the rear of the main shaft 1.

After the piston 16 is fitted, two oil holes are formed in the gap between the cylinder hole 4' at the front end of the piston 16, the step 4a of the sleeve 4, and the step 6a of the chuck sleeve 6. 4", residual air is removed and oil O is injected and filled.

Next, the operation of the above embodiment will be explained.

Prior to operation, the cap 12 is removed, replaced with a collet 9 having a diameter that matches the workpiece 11, and the cap 12 is fitted. After that, the workpiece 11 is inserted into the bore of the collet 9, and the hydraulic cylinder of the machine used is driven to advance the actuating tube 22 (rightward in Figure 1), and in conjunction with the actuating tube 22. A number of pistons 16 are also advanced.

As a result, the oil O filling the cylinder hole 4' and the gap between the stepped portion 4a of the sleeve 4 and the stepped portion 6a of the chucking sleeve 6 is compressed.
The hydraulic pressure generated by this increases the pressing force of the actuating pipe 22, and the chucking sleeve 6 also moves forward smoothly with a buffering effect.
The tapered surface 6b presses the tapered surface 9a of the collet 9. At the same time, since the reverse tapered surface 9b of the tip end of the collet 9 is received by the tapered surface 12a of the cap 12, the head of the collet 9 is held against the reverse tapered surface 9.
b, thereby causing the workpiece 11
will be tightened.

In this state, the machine starts operating, and this chucking operation can be performed whether the spindle head 1 is stopped or rotating.

This tightening action in this embodiment is similar to a conventional S-type collect chuck system. However, in this embodiment, the forward movement of the chucking sleeve 6 compresses the head of the collet 9. For this reason, in conventional actuating pipe adapters in which the tip of the adapter contacts or connects to the rear end of the chucking sleeve, the thrust force sometimes biases the sleeve and presses it, making the advancement unsmooth. There are some deficiencies, but they can be corrected to make them more reliable and powerful. That is, the actuation tube adapter 20
A large number of pistons 16 are attached to the piston receiver 18 through the piston receiver 18, and the pistons 16 are fitted and slid into the cylinder hole 4' of the sleeve 4 to compress the oil O filling the gap. The coupling sleeve 6 can be operated powerfully and smoothly.

The retraction of the chucking sleeve 6 when the collet 9 is relaxed is performed by the suction force of the oil O generated by the retraction of the piston 16 as the actuating tube adapter 20 is retracted.

At this time, collect 9 and tracking sleeve 6
However, when the rear end surface of the collet 9 comes into contact with the front end surface of the collect stopper ring 14, the chuck sleeve 6 continues to move back slightly, but the collet 9 stops. Since the adsorption force of the tapered surface 6b of the chucking sleeve 6 disappears, the collet 9 is completely opened by its own spring force, and the grip on the workpiece 11 is released.

In this embodiment, the pressing force from the fluid pressure cylinder connected to the actuating pipe 22 is approximately 4.3 times that of the case where only this cylinder is used. Therefore, with respect to the specified pressing force of the chucking sleeve 6, the pressing force of this fluid pressure cylinder can be reduced by a ratio of 4.3:1, and as a result, lowering the pressure of this fluid pressure cylinder allows the cylinder to be made smaller. It is possible to reduce the weight and eliminate troubles associated with the rotation of the main shaft of the machine used in large-sized machines.

Note that due to the presence of oil O, the operation of the chucking sleeve 6 is not caused by direct metal contact, so it is possible to prevent buffering and obtain a more balanced pressing force with hydraulic pressure, thereby making this operation extremely smooth. be able to.

[Effect of idea]

Since the present invention has the above-mentioned configuration, it is possible to increase the tightening force of the workpiece by the collector without increasing the size of the cylinder, thereby reducing the size and weight of the cylinder. It is possible to reliably eliminate various drawbacks associated with increased size.

Moreover, not only can grasping and release of the workpiece be done easily and quickly by moving the actuating tube forward and backward, but also the actuation of the chucking sleeve does not come into direct contact with the metal due to the presence of oil. Therefore, there is an effect that a pressing force is obtained with a balanced hydraulic pressure and that this operation can be performed extremely smoothly.

[Brief explanation of drawings]

1 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 2 is a right side view of FIG. 1, and FIG. 3 is a sectional view taken along line P-P' in FIG. 1. 1...Spindle head, 2...Adapter, 4...Sleeve, 4
a...Same stage part, 4'...Same cylinder hole, 4''...Same oil hole,
6...Chatting sleeve, 6a...Same stage part, 6b
...Same taper surface, 9...Collect, 9a...Same taper surface, 9b...Same reverse taper surface, 12...Cap, 12
a... Tapered surface, 14... Stop ring, 15... Plug screw, 16... Piston, 18... Piston holder, 20...
Actuation pipe adapter, 22... Actuation pipe.

Claims (1)

[Scope of utility model registration request] A substantially cylindrical sleeve 4 consisting of a rear thick wall part and a front thin wall part with a step 4a formed on the inner circumferential surface is provided with a cylinder hole 4' with both ends open in the thick wall part, and this sleeve 4 is connected to the adapter 2. Spindle head 1 of the machine used through
A chucking sleeve 6 is fitted into the sleeve 4, and has a stepped portion 6a opposite to the stepped portion 4a at approximately the center of the outer circumferential surface, and a tapered surface 6b on the front inner circumferential surface. This tapered surface 6 is formed inside the tracking sleeve 6.
A tapered surface 9a matching b and a reverse tapered surface 9 on the head.
A cap 12 having a tapered surface 12a abutting the reverse tapered surface 9b is fixed to the front end of the sleeve 4, and is further disposed inside the spindle head 1 to move back and forth. tube 22
The piston receiver 18 is fixed to the actuating pipe adapter 20 connected to the front end of the piston receiver 1, and the piston 16 is fitted into the cylinder hole 4'' with the piston 16 projecting backward, and the rear end of the piston 16 is connected to the piston receiver 1.
8, the sleeve 4 is provided with a closable oil hole 4'' for introducing oil into the gap between this step 4a and the step 6a of the chucking sleeve 6, and the oil is allowed to flow through the oil hole 4''. A collect chuck characterized in that all gaps communicating with the hole 4'' are filled with oil O.