JP3218685B2 - 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 work supporting device for holding a work rotatably by holding the work from both sides by a headstock and a tailstock.

[0002]

2. Description of the Related Art Conventionally, as a tailstock of a work supporting device,
For example, there is one described in Japanese Utility Model Publication No. 58-41042. In this type, when the tailstock center is engaged with the workpiece, the limit switch is urged, and the signal is used to lock the drainage of the cylinder that drives the tailstock ram forward and backward by the electromagnetic check valve, and to advance the tailstock ram. This is a configuration to stop.

The cycle of the conventional work supporting apparatus using the tailstock described above is as follows. First, the spindle center of the headstock is advanced, and the spindle center is advanced until just before contact with the work, and then the tailstock center of the tailstock is advanced, whereby the work is sandwiched between the spindle center and the tailstock center from both sides. . Then, one end of the work is clamped by the work holding device on the headstock side, and the work is rotatably supported. With the work supported, move the spindle center back and forth,
The work is positioned in the longitudinal direction. Next, the workpiece that is positioned and supported is ground, and after the grinding is completed, the work clamp by the work holding device is released at the same time as the tailstock center is retracted, and then the spindle center is retracted.

[0004]

As described above, after confirming that the spindle center has advanced to just before contacting the workpiece by advancement of the spindle center, advance of the tailstock center is performed. Was getting longer.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and comprises a headstock and a tailstock fixedly opposed to each other on a bed 1; A spindle ram having a spindle center at one end, a spindle ram advance / retreat drive device for driving the spindle ram forward / backward, and a rotation rotatably provided on the headstock to rotationally drive the work. a drive unit, the tailstock body slidably fitted in, provided with a heart push ram having a tailstock center at one end, and a heart press ram advancing drive device for advancing and retracting driving the heart press ram, the The spindle center ram and the tailstock center are contacted from both sides by the advancement of the spindle ram and the tailstock ram with respect to a work placed on a headstock and a temporary cradle installed on a bed between the tailstock. The workpiece is rotatably supported by contacting The rotary drive device, the work supporting device for rotating the workpiece, the spindle center and
Synchronously until just before the tailstock center contacts the workpiece
The tailstock is moved forward after the spindle center has been advanced.
The workpiece further and press the work against the spindle center.
And a control device for performing control so as to pinch it.

[0006]

With the above arrangement, first, the spindle center is advanced by the spindle ram advance / retreat drive until just before the spindle center comes into contact with the work. The tailstock ram is synchronized with the advance of the spindle center.
The tailstock center abuts the workpiece by the reciprocating drive
Advance just before After the spindle center advance is completed,
The center makes further progress and contacts the workpiece to
By pressing the tailstock center against the spindle center,
The work is clamped from both sides by the shaft center. Next, with the work supported, the spindle center is moved forward and backward to position the work in the longitudinal direction. Next, the workpiece is rotationally driven by the rotary drive device, and the workpiece that is positioned and supported is ground. After the grinding is completed, the tailstock center is retracted, and then the spindle center is retracted.

As described above, the advance of the spindle center and the tailstock
Center advance, that is, immediately before contact with the workpiece
And after the completion of the advance of the spindle center,
Advance the tailstock center further and adjust the spindle center and tailstock center.
The work is clamped from both sides by
The time spent on the tailstock center alone can be reduced,
Cycle time can be reduced.

[0008]

An embodiment of the present invention will be described with reference to the drawings.
In FIG. 1, reference numeral 1 denotes a bed, and
The work 3 is placed on the temporary receiving table 2. A headstock 4 and a tailstock 5 are fixed on the bed 1 so as to face each other with the work 3 interposed therebetween.

Reference numeral 4a denotes a headstock main body. A spindle ram 6 is slidably fitted to the headstock main body 4a, and a spindle center 7 is fitted to the tip of the spindle ram 6. The spindle ram 6 is fixed to a ball screw nut 8, and is driven forward and backward by a forward and backward drive motor 10 installed on the headstock body 4 a via a ball screw 9. The spindle ram 6
A work holding device 11 is provided at the end of the work holding device 11. In this work holding device 11, the face plates 12a and 12b are held by gripping claws 14a and 14b by connecting bars 13a and 13b, respectively.
b, and a face plate 12b
When the face plate 12a is relatively rotated with respect to the face plate 12b in a state where is fixed, the gripping claw 14b swings around the pin 14c, and clamps and unclamps the work 3. The face plate 12a is rotatably mounted on the main spindle body 4a via the face plate 12c.
5, the spindle gear 15 is attached to the headstock body 4a.
, And is rotatably driven by a rotation motor 16 installed in the camera.

Reference numeral 5a denotes a tailstock main body. A tailstock ram 17 is slidably fitted to the tailstock main body 5a, and a tailstock center 18 is fitted to the tip of the tailstock ram 17. I have. Also,
Reference numeral 19 denotes a cylinder formed on the tailstock main body 5a along the tailstock ram. In this cylinder 19, a piston 20a,
20b, 20c are inserted, and the oil chambers 21a, 21
b, 21c and 21d are formed. 22 is a piston 20
The pilot bar is slidably penetrated in the piston 20a integrally with b. A dog 23a is provided at the rear end of the pilot bar 22. When the tailstock center 18 advances one step, the tail end of the tailstock center 18 is stopped immediately before the work 3 at the rearward end position of the piston 20b. Dog 23a
The proximity switch 24a is provided at a position where the switch is turned ON. The tail end of the tail ram 17 is located at the rear end of the piston 20a.
Is connected to a shaft 26 fitted to the rear end via a spring 25 so as to be relatively movable in the axial direction. A dog 23b is provided at one end of the connecting member 27, and when the tailstock center 18 advances one step,
The proximity switch 24b is provided at a position where the piston 20a is turned on by the dog 23b at a position where the piston 20a moves forward and comes into contact with the piston 20b at the backward end.

Reference numerals 23c, 23d and 23e denote tailstock rams 1 respectively.
7, dogs 23c, 23d, 23
e, the proximity switch 24c is located at a position where the tailstock ram 17 is turned ON by the dog 23c at the reverse end position, and the proximity switch 24d is located at a position where the tailstock ram 17 is turned ON by the dog 23d at the one-step forward position of the tailstock ram 17. The proximity switch 2 is located at a position where the tailstock ram 17 is turned ON by the dog 23e at the forward end position.
4e are provided. When the tailstock ram 17 has advanced too far, the proximity switch 2 is activated by the dog 23d.
4c is turned on.

Reference numeral 28 denotes a hydraulic pump, 29 denotes a hydraulic pump 2
8 is an electromagnetic directional switching valve that switches and supplies the pressure oil from the oil chambers 8 to the oil chambers 21a and 21b of the cylinder 19, and switches and discharges the oil from the oil chambers 21a and 21b to the tank 31.
0a is a forward port, and 29B is a backward port. Also, 30 switches and supplies the pressure oil from the hydraulic pump 28 to the oil chambers 21c and 21d of the cylinder 19, and
An electromagnetic directional control valve for switching and discharging from 1d to the tank 31 is provided, 30A is a forward port of the piston 20b, 30B is a retreat port, and 30c is a discharge port from the oil chambers 21c and 21d.

DU1 is a drive unit for the electromagnetic directional control valve 29, DU2 is a drive unit for the electromagnetic directional control valve 30, DU3 is a drive unit for the forward / backward drive motor 10, and DU4 is a drive unit for the rotary motor 16. is there.
Reference numeral 32 denotes a control unit, and a central processing unit (CPU) 32a
, An interface (IF) 32b, and a memory 32c
In the memory 32c, a processing program for performing a predetermined processing by a processing device (not shown) on the work 3 supported by the work support device and a work support for supporting the work 3 by the work support device. A program is stored. This control device 32
Are proximity switches 24a, 24b, 24c, 24d, 24
The work support program is executed based on the signal e.
In other words, the positions of the tailstock ram 17 and the pistons 20a, 20b are checked at any time, and the electromagnetic direction switching valves 29, 30, the forward / backward drive motor 10, and the rotary motor 16 are controlled.

Next, the operation of the above configuration will be described.
With the spindle center 7 of the headstock 4 at the backward end position and the tailstock center 18 of the tailstock 5 at the backward end position, the work 3 is placed on the temporary receiving stand 2 installed on the base 1. Here, in the tailstock 5, the electromagnetic directional switching valve 29 is connected to the retreat port 29B.
Then, pressure oil is supplied from the pump 28 to the oil chamber 21b, the piston 20a is positioned at the reverse end, and the electromagnetic directional switching valve 30 is supplied with the discharge oil at the discharge port 31c to the other oil chambers. Absent.

In this state, the control device 32 executes the work support program stored in the memory 32c. First, the spindle center 7 of the headstock 4 is moved forward and backward by the drive motor 1.
It advances by a predetermined amount by 0, and advances just before contacting the work 3. At the same time, in the tailstock 5, the electromagnetic directional control valve 29
Is switched to the forward port 29A, the electromagnetic directional control valve 30 is switched to the reverse port 30B, and the pressure oil is supplied from the pump 28 to the oil chambers 21a and 21c, so that the piston 20a is located at the reverse end. 20b, the tailstock center 18 moves the work 3
1 step forward until just before contact.

Next, in the tailstock 5, the electromagnetic directional switching valve 29 is switched to the forward port 29A, the electromagnetic directional switching valve 30 is switched to the discharge port 30c, and the pressure oil is supplied from the pump 28 to the oil chamber 2.
By being supplied to 1a, the piston 20a and the piston 20b advance integrally. While the piston 20b moves to the forward end, the tailstock center 18 comes into contact with the work 3, and the tailstock center 18 comes into contact with the work 3, so that the shaft 26 moves forward.
The pressing force of the spring 25 inserted therein increases, and the piston 20b presses the spring 25 at the forward end position.
The tailstock center 18 presses the work 3 toward the spindle center 7. Here, the reason why the pressing force of the spring 25 is increased is to support the work 3 against a large load generated between the work 3 and a grindstone (not shown) during rough machining. In the case of finishing, the electromagnetic directional switching valve 29
Is the forward port 29A, the electromagnetic directional switching valve 30 is switched to the forward port 30A, and the piston 20c retreats by a predetermined amount by the pressurized oil from the pump 28. 26 retreats, the pressing force of the spring 25 is reduced, and the distortion of the work 3 is reduced.

Next, the work holding device 11 installed on the headstock 4 is operated to hold the work 3 by the gripping claws 14a, 14b.
Then, with the work 3 being supported, the spindle center 7 is advanced and retracted, and the work 3 is positioned in the longitudinal direction by an end face measuring device (not shown). The work 3 thus positioned and supported is machined according to the machining program. After machining, the work holding device 11 of the headstock 4 unclamps the work 3 and at the same time, the tailstock center 18 retreats, then the spindle center 7 retreats, and the entire program ends.

As described above, the advancement of the spindle center 7 and the advancement of the tailstock center 18 by one step, that is, the advance just before the tailstock is brought into contact with the workpiece 3, are performed in synchronization with each other.
Is moved forward by two steps to clamp the work 3 from both sides, so that the time spent for the advancement by the tailstock center 18 alone can be reduced, and the cycle time can be shortened. In addition,
In the above embodiment, in order to rotate the work 3,
A work holding device 11 is provided at the tip of the main spindle ram 6, and the work 3 is held by the work holding device 11 and the work 3 is driven to rotate by the rotary motor 16, but the flange portion 40a as shown in FIG. In the case of a work 40 having a work piece, a rotating member 41 having a drive pin 41a protruding in the longitudinal direction of the work 40 is rotatably fitted to the spindle ram 6, and the work 40 is held between the spindle center 7 and the tailstock center 18. When the driving pin 41a is engaged with a fitting hole formed in the flange portion 40a and the rotating member 41 is rotated by the rotary motor 16, the workpiece 40 is also rotated. Of the tailstock ram 17 and the one-step forward movement of the tailstock ram 17,
May be advanced two steps.

In the above-described two-stage advancement of the tailstock ram 17 of the tailstock 5, the pistons 20 a, 20 b, and 20 c are inserted into a cylinder 19 formed along the tailstock ram 17, and the piston 20 a , 20b, 20c and the cylinder 19 are controlled by switching the pressure oil supplied to the oil chamber. However, as shown in FIG.
2 and the ball screw 43, the connecting member 27 and the ball screw nut 44 are connected, and the forward movement of the spindle ram 6 and the one-step forward movement of the tailstock ram 17 are performed synchronously by NC control. You may advance two steps. Checking the position of the tailstock ram 17 by one step is performed by the dog 23d and the proximity switch 24.
After the completion of the advance of the spindle ram 6 is confirmed, a two-stage advance command of the tailstock ram 17 is given to the servomotor 42.

[0020]

As described above, according to the present invention, the tailstock ram advance / retreat drive device controls the advancement of the tailstock center of the tailstock to the spindle shaft.
In front of the workpiece in synchronization with the
The tailstock center further after the spindle center has been advanced.
And hold the work from both sides with the spindle center.
As a result, the time spent for forward movement by the tailstock center alone can be reduced, and the cycle time can be reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is an overall configuration diagram showing a second embodiment of the present invention.

[Explanation of symbols]

1 Bed 2 Temporary cradle 3 Work 4 Headstock 5 Tailstock 6 Spindle ram 7 Spindle center 8 Ball screw nut 9 Ball screw 10 Advance / retreat drive motor 11 Work holding device 12a, 12b, 12c Face plate 13a, 13b Connection bar 14a, 14b Gripping claw 14c Pin 15 Spindle gear 16 Rotary motor 17 Tailstock 18 Tailstock center 19 Cylinder 20a, 20b, 20c Piston 21a, 21b, 21c, 21d Oil chamber 22 Pilot bar 23a, 23b, 23c, 23d, 23e Dog 24a, 24b, 24c, 24d, 24e Proximity switch 25 Spring 26 Shaft 27 Connecting member 28 Hydraulic pump 29, 30 Electromagnetic directional switching valve 31 Tank

Claims (1)

(57) [Claims] 1. A headstock and tailstock fixedly opposed to each other on a bed 1, a spindle ram slidably fitted to the headstock body, and having a spindle center at one end, and a spindle ram. A spindle ram reciprocating drive device for advancing and retreating, a rotary drive device rotatably provided on the headstock, and rotatably driving a work, and slidably fitted to the tailstock main body, and a tailstock at one end. A tailstock having a center, and a tailstock ram advance / retreat drive device for driving the tailstock ram forward / backward, and mounted on a temporary cradle installed on a bed between the headstock and the tailstock. The spindle center ram and tailstock ram are brought into contact from both sides by the advancement of the spindle ram and tailstock ram with respect to the completed work, and the work is rotatably supported, and the work is rotationally driven by the rotation drive device. in the work supporting device, the main Center and the heart push center abuts against the workpiece
The spindle is advanced to the point just before
After that, the tailstock center is further advanced and the work is
A work support device, comprising: a control device that controls the work so as to be pressed against an axis center to hold the work.