JPH106107A - Device to position work in main spindle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To a provide a device to position a work in a main spindle to prevent damage to the inner wall of a main spindle hole and a work and the occurrence of defective machining due to core displacement by grasping a tip part from the chuck side. SOLUTION: A feed screw part 10c formed at the rear cover 9 of a rotatable and positioning main spindle 3 and threadedly engaged with a nut is arranged at a rear part and a sizing shaft 10 provided at a tip with a part 10b to be sized is movably arranged in the hole of the main spindle 3. A detent device 30 provided at the upper end of a piston rod 16 with a lock block 18 disengageably engaged with the retained part of the sizing shaft 10 is arranged at the upper left end of a bed 1. In a station that rotation of the sizing shaft 10 is blocked by the lock block, a sizing center 10b is positioned in a work support position, fronting on a hole of a chuck 4, by axial movement positioning of the sizing shaft 10 through rotation of the main spindle 3. The work W is supported between two centers of the tailstock 23 and the sizing shaft 10, a part and most of the work W, being a shaft object, is inserted in a main spindle hole through movement of the sizing shaft 10 and the tailstock 23, and the tip part is grasped by the chuck 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for axially positioning an axial workpiece when a part of or a part of a relatively long axial workpiece is inserted into a spindle hole and the front end is gripped by a spindle chuck. It is.

[0002]

2. Description of the Related Art Conventionally, when turning an end portion of a relatively long shaft work, a part or most of the shaft work is inserted into a center hole of a spindle from a chuck side, and a tip end portion is gripped and machined by a spindle chuck. Often. As shown in FIG. 6, a method of positioning the axial workpiece in the axial direction at the time of mounting the workpiece is such that the axial workpiece W is inserted into a main shaft hole, and the distal end of the fixed-size stopper 101 whose longitudinal position can be adjusted manually. Usually, the axial position is determined by hitting the center hole, and the front end of the work is gripped by the spindle chuck 102 to cut the portion protruding from the chuck.

[0003]

With the fixed-size stopper described in the prior art, the position of the fixed-size stopper must be manually adjusted every time the length of the shaft workpiece changes, but the main shaft rotating portion is provided with a cover for safety. It is usually covered, and it takes a long time to adjust the position of the fixed-size stopper including the attachment and detachment of the cover.

If the length of the shaft work is short, the center hole is relatively close to the main shaft hole so that the center hole can relatively easily face the center of the shaft work. If the length is long, the sizing center is located at the back, so it is difficult to make the center hole face the sizing center, and the spindle hole and the work are easily damaged when the work is mounted. (A state not in contact with the fixed size center)
There is a problem that processing will be defective if processed as it is. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and an object of the present invention is to provide a workpiece positioning device in a spindle capable of moving and positioning a fixed size center with a simple structure. Is what you do.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, a spindle work positioning apparatus according to the present invention is provided for inserting a shaft work from a chuck side into a spindle hole of an NC lathe and gripping a tip portion with the chuck. An apparatus for axially positioning the shaft work, wherein a main shaft rotatable and a feed screw portion screwed to a nut member fixed concentrically to a rear end portion of the main shaft are provided at a rear portion, and a front portion is provided with the main shaft. A sizing shaft having a sizing center portion which is guided concentrically in the hole so as to be axially movable and engages with a center hole on the insertion side of the shaft work, and a held portion provided on the sizing shaft. A holding member that can be positioned at a holding position and a holding release position for preventing rotation of the fixed-size shaft, a driving unit that moves the holding member between the holding position and the holding release position, and a rotation detector for the main shaft. Inspection for moving positioning of fixed size axis Comprises a means for switching the vessel, in which by rotating the nut by rotating the spindle to position by moving the sizing shaft in the axial direction while preventing rotation of the sizing shaft.

An apparatus for inserting an axial workpiece from the chuck side into a spindle hole of an NC lathe and positioning the axial workpiece in the axial direction when the tip is gripped by the chuck, wherein the axial workpiece is moved in the axial direction of the spindle. A tailstock that can be positioned, a main shaft that can be rotated and positioned, and a feed screw portion that is screwed with a nut member fixed to the rear end of the main shaft concentrically have a front portion that can move axially concentrically within the main shaft hole. A sizing shaft having a sizing center portion which is guided by the tip and engages with a center hole on the insertion side of the shaft workpiece, and a held portion provided on the feed screw portion of the sizing shaft, A holding member movable between a holding position and a holding release position for preventing rotation of the fixed-size shaft, a driving unit for moving the holding member between the holding position and the holding releasing position, and holding and releasing the holding member Hold confirmation signal and Hold release confirmation signal Doo and means for outputting respectively, becomes a rotational position detector of the spindle in the holding confirmation signal and means for switching the mobile positioning detector of the sizing shaft,
By rotating the spindle while the rotation of the sizing shaft is prevented, the nut is rotated to move the sizing shaft in the axial direction, and the sizing shaft and the tailstock are positioned at an outer position near the entrance of the spindle hole. The center work is supported between the two centers, and a part or most of the shaft work is inserted into the main shaft hole and positioned by moving the fixed-size shaft and the tailstock.

According to the work positioning device in the main spindle according to the first aspect of the present invention, by rotating the main spindle in a state where the rotation of the fixed dimension shaft is prevented, the nut side is rotated to perform the movement positioning of the fixed dimension shaft. With this configuration, the sizing center can be adjusted easily and in a short time with a simple structure using an existing NC axis.

According to the workpiece positioning device in the spindle according to the second aspect of the present invention, the fixed-size axis for rotating and positioning the nut by rotating the spindle while the rotation is prevented, and the movable positioning can be performed. By positioning the movement with the tailstock, the shaft work supported between the center of the sizing shaft and the tailstock at the position outside the mouth of the spindle hole is inserted into the spindle hole and positioned. Simple structure using NC axis, stable work without damage to the work and the main spindle, and processing failure due to misalignment. Positioning of the work inside the main spindle and attachment / detachment by the chuck are possible. Automatic attachment / detachment by robot or work loader is possible. Thus, it is effective for fully automatic machining of relatively long shaft workpieces.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a main shaft longitudinal positioning device according to an embodiment of the present invention. FIG.
Is a configuration diagram of a lathe having a workpiece positioning device in the spindle,
FIG. 2 is an enlarged view of a detent device for preventing rotation of the fixed-size shaft,
FIG. 3 is a sectional view taken along line AA of FIG.

In FIG. 1, a headstock 2 is fixed on the left side of a bed 1, and a spindle 3 is rotatably mounted on the headstock 2 by a plurality of bearings. The chuck 4 is concentrically fixed to the tip of the main shaft 3, and the rotating side 8b of the position detector 8 and the rotating cylinder 5 are concentrically fixed to the rear end. A draw tube 6 for opening and closing a chuck gripping claw connected to the hollow piston rod of the rotary cylinder 5 is inserted into the center hole of the main shaft 3 so as to be movable in the axial direction. Also serves as a guide hole.

A fixed side 8a, which is a pair with the rotating side 8b of the position detector 8, is fixed to the rear end face of the main shaft 2, and the position detector 8 normally detects the rotational position of the main shaft 3 and outputs an NC (not shown). Output to the device. Further, at the rear end of the rotary cylinder 5, a feed screw 10
A rear lid 9 having a nut screwed with c is fixed,
The rear lid 9 is provided with a rotary brake including a spring 9a and a steel ball 9b so that the fixed-size shaft does not easily rotate during rotation of the main shaft.

The sizing shaft 10 having a feed screw portion 10c at the rear portion thereof to be screwed with the nut of the rear cover 9 has a front portion guided in the center hole of the draw tube 6 via a guide ring 10d so as to be movable in the axial direction. In addition, a fixed size center 10b having the same taper angle as the center hole of the end surface of the shaft workpiece W is integrally formed at the tip, and an air hole 10a penetrates the center. Air hole 10
Air is supplied to a from an air source (not shown) through a pipe 12 and a rotary joint 11, and a pressure switch 13 for confirming center engagement based on a difference in air pressure is mounted in the middle of the pipe 12.

A detent device 30 for the fixed-size shaft 10 is provided on the left end of the bed 1 and on the left side of the headstock 2. The hydraulic or pneumatically driven hydraulic cylinder 15 of the detent device 30 is
As shown in the enlarged view of FIG.
It is fixed vertically and upward by a support 14 above,
At the upper end of the piston rod 16 integrated with the piston 16a,
A flat plate-shaped locking piece 18 is fixed, and the locking piece 18 has a feed screw portion 10c of the fixed-size shaft 10 as shown in FIG.
Part (holding part) 10e engraved on the outer periphery of
An engagement groove 18a is formed in the engagement groove 18a so that the engagement groove 18a is engaged (retained) with the engagement groove 18 so as to be freely engaged and disengaged.

Further, the rotation of the piston rod 16 is restricted by the detent pin 17 so that it can be moved only in the axial direction.
A dog 21 is fixedly attached to the lower end portion, and an engagement confirmation switch 22a such as a limit switch or a proximity switch and an engagement release confirmation switch 22b are provided at positions of the support 14 corresponding to the dog.
And are installed side by side.

Accordingly, as shown in FIG. 3, when the pressurized fluid is supplied to the lower chamber of the fluid pressure cylinder 15 through the pipe line 20, as shown in FIG. The engagement groove 18a of the locking piece 18 engages with the two-way portion 10e of the sizing shaft 10 to prevent the rotation of the sizing shaft 10, and an engagement (hold) confirmation signal from the engagement confirmation switch 22a is shown. Not output to the NC device. Further, when the pressure fluid supplied from the pipe line 20 to the lower chamber is cut off, the piston rod 16 is lowered to the engagement (holding) releasing position by the force of the spring 19, and the engagement is released when the rotation of the fixed-size shaft 10 becomes free. An engagement release confirmation signal is output from the confirmation switch 22b to the NC device.

When this engagement confirmation signal is input, the NC device switches to fixed-size axis control for controlling the movement of the fixed-size axis 10 in the axial direction by the detection signal of the position detector 8.
Simultaneously with the switching, the position of the fixed axis from the machining origin (retracted end) stored by the previous disengagement signal is called, and by rotating the main shaft 3, it overcomes the rotary brake incorporated in the rear cover 9. By rotating the nut, the sizing shaft 10 moves in the axial direction. Then, the position detector 8 detects the axial position of the sizing shaft 10 from the machining origin, compares the position with the program command value, and performs movement positioning.

A tailstock 23 is movably mounted on a Z-axis guide provided on the bed 1 in the direction of the center axis of the spindle. The tailstock 23 can be moved and positioned in the Z-axis direction (not shown). The saddle is connected to the saddle by a hook member which can be detached by hydraulic drive, and is moved and positioned together with the saddle. A tailstock shaft 23a is fitted to the tailstock 23 so as to be axially movable concentrically with the main shaft 3, and the tailstock shaft 23 is moved between a standby position and a work support position by a hydraulic cylinder (not shown). The tailstock center 24 is detachably fitted in the tapered hole at the tip of the tailstock shaft 23a.
On the other hand, a work transfer lot is installed on the floor near the bed 1, and a robot hand 25 having a gripper 25b that can be opened and closed is attached to the tip of a robot arm 25a.

Next, the operation of the in-spindle workpiece positioning apparatus of the present invention will be described with reference to the flowcharts of FIGS.
First, the mounting operation of the work W will be described with reference to FIG.
In step S1, a pressurized fluid is supplied to the lower chamber of the fluid pressure cylinder 15, the piston rod 16 is raised to the engagement position, and the locking piece 18 at the upper end is fixed at the home position (retracted end position). The rotation of the fixed-size shaft 10 is prevented by engaging the two-way chamfered portion 10e of the shaft 10, and in step S2, the NC is switched to the fixed-size shaft control by the output signal of the engagement confirmation switch 22a. By this switching, the position from the machining origin of the fixed dimension shaft 10 at the time of the previous disengagement is called.

In step S3, the rotation of the main shaft 3 causes the sizing shaft 10 to move to the work supporting position where the sizing center portion 10b at the tip faces the center hole of the chuck 4. Step S
4, the tailstock 23 waiting at the right end position of the bed 1
Is connected to the saddle so that it can be moved and positioned. In step S5, the work W gripped by the robot hand 25 is carried into the machine and positioned concentrically with the spindle as shown in FIG. 1, and then the robot hand 25 is moved in the Z-axis direction to the center of the left end of the work W. Centered hole 10
b. In step S6, the tailstock 23 is moved to the main spindle side in the Z-axis direction, the tailstock center 24 is moved to near the right end of the work W, and then the tailstock shaft 23a is advanced to support the center hole of the work W.

Next, in step S7, the fixed-size shaft 1
Air is supplied to the zero-sized air hole 10a, and the presence or absence of air leakage from the fixed size center 10b is detected by the pressure difference in the pipe 12 by the pressure switch 13, and the engagement between the fixed size center 10b and the center hole is confirmed. . In step S8, it is checked whether the engagement is OK. If the pressure in the pipeline is lower than near the set value, the result is NO, the process returns to step S7, and this process is repeated until the result is YES. When the repetition becomes longer and a set time elapses, a timer (not shown) operates to stop the alarm (flow chart is omitted). If the pressure in the pipeline has risen to near the set value, the result is YES, and a work support confirmation signal is output from the pressure switch 13. After the gripping claws 25b of the robot hand 25 are opened and the work W is released in step S9, Ascends and separates from work W.

Then, in step S10, the work W supported between the centers 10b and 24 is inserted into the spindle hole by the synchronous movement of the sizing shaft 10 and the tailstock 23 to the left in the Z-axis direction, and a program command is issued. Positioned in position. In step S11, the supply of the pressurized air to the hydraulic cylinder 15 is stopped, and the piston rod 16 is lowered to the disengaged position by the force of the spring 19, and the locking piece 18 is moved from the two-way portion 10e of the fixed-size shaft 10. As a result, the integral rotation of the fixed-size shaft 10 and the main shaft 3 is free, and in step S12, the disengagement is OK.
If the signal is output from the disengagement confirmation switch 22b, the determination is YES, and the
Is stored, and if no signal is output, the result is NO.

If NO, the process returns to step S11, and steps S11 and S12 are repeated. Note that when this repetition becomes longer and a timer setting time (not shown) expires, the alarm stops (flow chart is omitted). In the case of YES, in step S13, the position of the fixed size shaft 10 from the machining origin is stored in the engagement release confirmation signal at this time,
The position detector 8 is switched for spindle rotation detection. In step S14, pressure oil is supplied to the right chamber (front chamber) of the rotary cylinder 5, the draw tube 6 is pulled in, the gripping claws 4a of the chuck 4 close, and the tip end of the work W is gripped.
Next, in step S15, the tailstock 23 moves to the side opposite to the main spindle in the Z-axis direction and separates from the work W, and at the same time, the tailstock shaft retreats, and the tailstock 23 stands by on the upper right side of the bed 1 and can perform cutting. It becomes a state.

Next, the operation of removing the work W will be briefly described with reference to FIG. When the cutting is completed, in step S17, the tailstock 23 moves to the left in the Z-axis direction from the standby position, and supports the center hole on the processing side end surface of the work by the advancement of the tailstock shaft 23a. The fixed position is stopped, and the two-way portion 10e of the fixed-size shaft 10 is indexed to a rotational position at which the locking piece 18 can be engaged.

Next, in step S19, the gripping claws 4a of the chuck are opened to release the work W, and in step S20, the pressure fluid is supplied to the lower chamber of the fluid pressure cylinder 15, and the locking piece 18 is moved to the fixed dimension shaft. 10 two-way section 1
0e, the rotation of the sizing shaft 10 is stopped, and when the engagement confirmation signal is output, the position of the sizing shaft previously stored from the machining origin is called, and the sizing shaft 10 is rotated by the main shaft rotation. In the axial direction.

Next, in step S21, the work W supported between the centers 10b and 24 is removed by the synchronous movement of the sizing shaft 10 and the tailstock 23 to the right in the Z-axis direction.
That is, the sizing center 10b is moved to the same position as the above-described work supporting position facing the center hole of the chuck 4, and in step S22, the robot hand 25 descends to grip the substantially central portion of the work W, and in step S23,
The tailstock 23 moves to the opposite side of the spindle in the Z-axis direction, and at the same time, the tailstock shaft 23a retreats and the tailstock 23 returns to the standby position. In step S24, the robot hand 25 moves to the side of the opposite spindle to the Z-axis direction. Then, the work W is extracted from the center hole of the chuck 4 and then moved up to carry the work W out of the machine.

Although the above embodiment has been described with reference to fully automatic machining, the present invention is not limited to this. When the operator wants to arbitrarily change the position of the sizing center, the operator switches the hydraulic pressure to be supplied to the fluid pressure cylinder 15 and the sizing axis control of the position detector 8 so that the NC can be controlled by the NC. The position of the sizing center can be changed by operating the apparatus.

[0027]

The work positioning device in the spindle according to the present invention is constructed as described above, and has the following effects. According to the first aspect of the present invention, the spindle of the sizing center using the spindle rotation position control of the NC for rotating and positioning the sizing axis by rotating the nut side by the rotation of the main spindle while the rotation of the sizing axis is prevented. Since the positioning is performed in the direction, the setup time can be reduced with a simple structure by using the existing NC axis.

According to the second aspect of the present invention, since the workpiece is positioned in the axial direction by utilizing this, it is possible to automate a wide variety of workpieces, which is effective for unmanned operation and labor saving.

Further, the sizing shaft is advanced to near the entrance in the spindle hole, and the work is inserted into the spindle hole by moving the sizing shaft and the tailstock while the work is supported by the sizing center and the tailstock center. As a result, the work or the spindle hole is not damaged, and processing defects due to misalignment are eliminated. In addition, because of the structure in which the fixed-size axis is moved and positioned by the spindle motor, it is possible to install the intra-spindle work positioning device of the present invention on a movable headstock that can move in the direction of the spindle axis, thereby expanding the range of use. Can be expected.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a lathe having a work positioning device in a spindle.

FIG. 2 is an enlarged view of a detent device that prevents rotation of a fixed-size shaft.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a flowchart for explaining a work mounting operation of the present invention.

FIG. 5 is a flowchart for explaining a work removing operation of the present invention.

FIG. 6 is a configuration diagram of a conventional sizing center in a spindle according to the related art.

[Explanation of symbols]

1 Bed 2 Headstock 3 Spindle 4 Chuck 5 Rotating Cylinder 10 Sizing Shaft 10a Air Hole 10b Sizing Center 10c Feed Screw 10e Two-way Cutout 15 Fluid Pressure Cylinder 18 Locking Piece 22a Engagement Confirmation Switch 22b Disengagement Confirmation switch 23 Tailstock 23a Tailstock 24 Tailstock center 25 Robot hand 30 Detent device

Claims (2)

[Claims] 1. A device for inserting an axial workpiece from the chuck side into a spindle hole of an NC lathe and positioning the axial workpiece in the axial direction when gripping a tip end of the spindle workpiece. A rear end portion of a feed screw portion screwed to a nut member fixedly concentric with the main shaft rear end portion, the front portion being guided concentrically in the main shaft hole so as to be movable in the axial direction, and a front end having a center hole on the insertion side of the shaft work. A sizing shaft having a sizing center portion that engages with the sizing shaft; and a holding position for holding a held portion provided on the sizing shaft and preventing rotation of the sizing shaft and a holding release position. A holding member, a driving unit for moving the holding member between a holding position and a holding release position, and a unit for switching a rotation detector of a main shaft to a movement positioning detector of the sizing shaft. Turn the spindle while the shaft rotation is blocked. An in-spindle workpiece positioning device, characterized in that the nut is rotated to rotate the nut, thereby moving and moving the sizing axis in the axial direction. 2. An apparatus for positioning an axial work in an axial direction when inserting a shaft work from a chuck side into a main spindle hole of an NC lathe and gripping a tip end portion with the chuck, wherein the axial work is moved in a spindle axial direction. A tailstock that can be positioned, a main shaft that can be rotated and positioned, and a feed screw portion that is screwed with a nut member fixed to the rear end of the main shaft concentrically have a front portion that can move axially concentrically within the main shaft hole. A sizing shaft having a sizing center portion which is guided by the tip and engages with a center hole on the insertion side of the shaft workpiece, and a held portion provided on the feed screw portion of the sizing shaft, A holding member movable between a holding position and a holding releasing position for preventing rotation of the fixed-size shaft, a driving unit for moving the holding member between the holding position and the holding releasing position, and holding and releasing the holding member The hold confirmation signal and the hold release confirmation signal Means for outputting, and means for switching the rotational position detector of the main shaft with the holding confirmation signal to the detector for moving and positioning the fixed-size axis,
By rotating the spindle while the rotation of the sizing shaft is prevented, the nut is rotated to move the sizing shaft in the axial direction, and the sizing shaft and the tailstock at an outer position near the entrance of the spindle hole. A work for supporting the shaft work between the two centers, and inserting or positioning a part or most of the shaft work in the spindle hole by movement of the fixed-size shaft and the tailstock.