JPH09123005A - Collet chucking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten time for stage exchange, with regard to a collect chucking device for clamping the axial end of a work, when there is a change in the diameter of a clamping portion of the work or the position or the diameter of a phase reference pin taken place in conjunction with the change of a workpiece. SOLUTION: It is contrived to change only an auxiliary collect 12 in making a job plan exchange by providing a plurality of kinds of auxiliary collect 12 having respectively different inside diameters corresponding to a workpiece depending upon the common outside diameter corresponding to a main collet 7 and the types of workpieces and constituting the auxiliary collect 12 selected in accordance with the type of a workpiece W inserted into the main collet 7 and clamp the workpiece W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collet chuck device which is provided at the end of a spindle of a machine tool such as a grinder and clamps the shaft end of a workpiece.

[0002]

2. Description of the Related Art A conventional collet chuck device is shown in FIG. 2, for example. In this structure, the collet sleeve 22 is formed integrally with the piston 24, and the phase reference key 21 is fixed to the connecting face plate 20. Here, when the diameter of the clamped portion or the position of the phase reference changes due to the change of the workpiece W, it is necessary to perform setup change to the collet and the phase reference key corresponding to the workpiece W. Then, at the time of setup change, it is necessary to remove the connecting face plate 20 and replace the entire collet chuck device, resulting in poor workability and reduced productivity.

To solve this problem, there is JP-A-6-312306 in which only the phase reference key, collet and collet sleeve can be replaced without replacing the entire collet chuck device. This is shown in FIG.
As shown in, the collet sleeve 32 is detachably attached to the piston 34, and the collet 33 and the phase reference key 31 are detachably attached to the connecting face plate 30.

[0004]

However, Japanese Patent Application Laid-Open No.
-312306 has a problem in removing the collet sleeve 32. That is, since the fitting between the collet sleeve 32 and the cylindrical member 35 affects the runout accuracy of the workpiece during clamping, the dimensional accuracy is strictly controlled, and the collet sleeve 3 is used as it is used.
Chips and the like adhere between the 2 and the cylindrical member 35, making it difficult to attach and detach the collet sleeve 32. further,
Since the collet sleeve 32 has a relatively large diameter, in order to replace the collet sleeve 32 on the machine, it is necessary to remove a table top device such as an anti-vibration device or a workpiece loading / unloading device. Takes time.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the invention according to claim 1 is a cylinder formed on a rotationally driven main shaft,
A collet comprising a piston fitted in the cylinder, a collet sleeve connected to the piston and having a first tapered surface, and a main collet having a second tapered surface engaging with the first tapered surface. The chuck device is provided with a plurality of types of auxiliary collets corresponding to the type of the work, and the plurality of types of auxiliary collets are different from each other depending on the common outer diameter corresponding to the main collet and the type of the work. The auxiliary collet, which has an inner diameter and is selected according to the type of the work, is inserted into the main collet to clamp the work.

Further, the invention according to claim 2 is characterized in that the auxiliary collet is provided with a phase reference for matching the phase of the workpiece with the phase of the main axis. Further, the invention according to claim 3 is characterized in that the auxiliary collet is inserted into the main collet in a state of being attached to a workpiece, and the invention according to claim 4 is The work is inserted with the auxiliary collet attached to the main collet.

With the above construction, when the cylinder is retracted (advanced), the main collet is retracted (pushed out) by the action of the first taper surface provided on the collet sleeve and the second taper surface provided on the main collet. , The main collet is deformed in the direction orthogonal to the rotation axis of the main shaft, and the workpiece is clamped (unclamped) via the auxiliary collet.
Here, when the type of the workpiece is changed and the diameter of the clamped portion of the workpiece or the position or diameter of the phase reference pin is changed, only the auxiliary collet may be replaced with the one corresponding to the workpiece.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. A center 3 is attached to the rotation center O of the main shaft 2, and the collet chuck device 1 is attached to the end face of the main shaft 2 via a rotary face plate 4. A connecting face plate 5 is attached to an end face of the rotating face plate 4 opposite to the main shaft 2, and the connecting face plate 5 is formed with an extension portion 5a having a convex shape in the workpiece W direction on the rotation center O side. Has been done. A cylindrical member 6 is fixed to the end face of the connecting face plate 5 opposite to the rotary face plate 4. Further, a main collet 7 is inserted on the outer periphery of the extension portion 5a of the connecting face plate 5, and is fixed to the connecting face plate 5 by a bolt (not shown). The main collet 7 has a thin central portion and a plurality of slits provided in the direction of the rotation center O, and a force is applied to the tip portion in a direction perpendicular to the direction of the rotation center O, whereby the thin wall is formed. The tip portion is configured to be bent to reduce its diameter. A second tapered surface 7a is formed on the outer circumference of the tip portion.

A cylinder 8 is formed on the cylindrical member 6, and a piston 9 is fitted in the cylinder 8. Pressure chambers 8a and 8b are formed in front of and behind the piston 9, and a supply passage 10a for supplying hydraulic oil to the pressure chamber 8a extends from the main shaft 2 to the rotary face plate 4 and the connecting face plate 5 to the pressure chamber 8b. A supply path 10b for supplying the electric field is formed from the main shaft 2 to the rotating face plate 4, the connecting face plate 5 and the cylindrical member 6. A collet sleeve 11 is formed at the tip of the piston 9, and a first tapered surface 11a that engages with the second tapered surface 7a is formed on the inner circumference of the collet sleeve 11.

An auxiliary collet 12 is provided in the main collet 7.
Is inserted. A plurality of types of the auxiliary collet 12 are prepared according to the type of the work W. These auxiliary collets 1
Similarly to the main collet 7, reference numeral 2 has a thin central portion and a plurality of slits provided in the direction of the rotation center O, and a force is applied to the tip portion in a direction perpendicular to the direction of the rotation center O. As a result, the thin portion is bent so that the tip portion is reduced in diameter. Here, the outer diameters of the auxiliary collets 12 are common and set to a diameter that can be clamped by the main collet 7. On the other hand, the inner diameter of the auxiliary collet 12 is set to a diameter capable of clamping the clamped portion of the workpiece for each type of workpiece, and corresponds to the position and diameter of the phase reference pin P provided on the workpiece. The slit 12a is provided. Further, the rear end of the auxiliary collet 12 is fitted into a recess 5b provided at the tip of the extension 5a of the connecting face plate 5, and a slit 12b corresponding to the positioning pin 5c provided in the recess 5b is formed. There is. The shape of the rear end portion of the auxiliary collet 12 is also set to be common, like the outer diameter.

The operation of the collet chuck device having the above structure will be described. Prior to processing the workpiece W, the auxiliary collet 12 corresponding to the workpiece W is attached to the workpiece W outside the machine. At this time, it is necessary to match the phases of the two so that the phase reference pin P provided on the workpiece and the slit 12a provided on the auxiliary collet 12 are engaged with each other. This attachment work can be done manually by an operator, an auxiliary collet attachment function can be added to the workpiece loading / unloading device, or a dedicated robot can be used. obtain.

Next, the positioning pin 5c provided on the connecting face plate 5 is provided with the slit 12b provided on the auxiliary collet 12.
The auxiliary collet 12 by matching the phases so that
The workpiece W attached with is inserted into the collet chuck device 1. Here, the hydraulic oil is supplied from the supply passage 10 to the pressure chamber 8b.
Is supplied to the piston 9, the piston 9 retracts. The collet sleeve 11 is retracted as the piston 9 retracts, and the main collet 7 rotates due to the engaging action of the first tapered surface 11a provided on the collet sleeve 11 and the second tapered surface 7a provided on the main collet 7. The auxiliary collet 12 is pressed by being deformed in a direction orthogonal to the center O and reducing the diameter of the tip. Then, the auxiliary collet 12 is deformed in the direction orthogonal to the rotation center O, and the tip portion is reduced in diameter to clamp the workpiece W. On the contrary, if hydraulic oil is supplied to the pressure chamber 8a, the work W is unclamped by the action opposite to the above.

If the diameter of the clamped portion of the workpiece or the position or diameter of the phase reference pin is changed by changing the type of the workpiece, the auxiliary collet 12 corresponds to the workpiece. Since the outer diameter of the auxiliary collet 12 and the shape of the rear end of the auxiliary collet 12 are all configured in common, the collet chuck device 1 side can clamp different kinds of workpieces without any setup change. You can

In the above embodiment, the auxiliary collet 12 is used.
Although the case of inserting into the main collet 7 while being attached to the workpiece W in advance has been described, the auxiliary collet 12 may be attached to the main collet 7 in advance.
That is, the auxiliary collet 12 is detachably fixed to the connecting face plate 5 with, for example, bolts, and the auxiliary collet 1
When the work W is changed, the work W is inserted while the work W is installed in the main collet 7.
The bolt is removed and the auxiliary collet 12 is replaced. With this configuration, it is not necessary to attach or detach the auxiliary collet outside the machine.

In the above-described embodiment, the collet chuck device for clamping the work requiring the phase reference such as the camshaft, the crankshaft or the work having the eccentric portion has been described, but the phase reference is not necessary. Even in the case of a workpiece, if the diameter of the clamped portion is changed depending on the type of the workpiece, the collet chuck device of the present invention can be used to shorten the setup change time.

[0016]

According to the invention described in claim 1 of the present application, a plurality of types of auxiliary collets having a common outer diameter corresponding to the main collet and an inner diameter different depending on the type of the workpiece are provided. When the type of work piece is changed, it is only necessary to change the auxiliary collet to the one corresponding to the work piece, and the time required for setup change can be greatly shortened.

According to the second aspect of the present invention, when the workpiece having the phase reference is clamped, even if the position or shape of the phase reference pin or the phase reference key is changed by changing the type of the work, Only the auxiliary collet needs to be changed to the one corresponding to the phase reference, and the setup change time due to the change of the phase reference can be shortened. According to the invention of claim 3 of the present application, the auxiliary collet is inserted into the main collet while being attached to the workpiece outside the machine, so that the auxiliary collet on the machine can be changed when the type of the workpiece is changed. No setup change work is required.

According to the fourth aspect of the present invention, when the type of workpiece is changed, only the auxiliary collet needs to be replaced on the machine, and the auxiliary collet can be easily attached and detached as compared with the collet sleeve. Moreover, since the auxiliary collet has a smaller diameter than the collet sleeve, it is not necessary to remove the table top device as in the past even if the setup change is performed on the machine, so the workability of the setup change on the machine is improved. To do.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a collet chuck device of the present invention.

FIG. 2 is a sectional view showing a conventional collet chuck device.

FIG. 3 is a sectional view showing another conventional collet chuck device.

[Explanation of symbols]

 W Workpiece P Phase reference pin 1 Collet chuck device 2 Spindle 3 Center 4 Rotating face plate 5 Connecting face plate 6 Cylindrical member 7 Main collet 8 Cylinder 9 Piston 10a Supply path 10b Supply path 11 Collet sleeve 12 Auxiliary collet

Claims (4)

[Claims] 1. A cylinder formed on a rotationally driven main shaft, a piston fitted to the cylinder, a collet sleeve connected to the piston and having a first tapered surface, and the first tapered surface. A collet chuck device comprising a main collet having a second taper surface that engages with a plurality of types of auxiliary collets corresponding to the types of workpieces, the plurality of types of auxiliary collets being common to the main collet. Of the auxiliary collet selected according to the type of the workpiece is inserted into the main collet to clamp the workpiece. A collet chuck device characterized by: 2. The collet chuck device according to claim 1, wherein the auxiliary collet is provided with a phase reference for matching the phase of the workpiece with the phase of the spindle. apparatus. 3. The collet chuck device according to claim 1, wherein the auxiliary collet is inserted into the main collet while being attached to a workpiece. 4. The collet chuck device according to claim 1, wherein a workpiece is inserted in a state where the auxiliary collet is attached to the main collet.