JPH0516058A - Rotary grinding machine - Google Patents

Abstract

PURPOSE:To improve the machining accuracy and prolong the service life of a cutting tool such as a grinder in cutting a groove into a workpiece and attaining the mirror surface finish thereof to the required high precision as in the manufacture of a magnetic head. CONSTITUTION:In a rotary grinding machine, for example, to cut a groove into a workpiece W where the workpiece W fixed on a slide table 14 freely slidable on a bed 13 is ground with a grinder 3 fitted to one end of an air spindle rotor shaft 1 kept within a housing 2 and capable of rotating via a rotor 4 and a stator 5, non-contact displacement sensors 16a and 16b are respectively laid on the aftward side of a motor rear cover 15 fitted to the rear end of the housing 2 and the aftward side of the housing 2. These sensors 16a and 16b detect the rear and side displacement of a spindle tail section due to the rotating vibration of the shaft 1. In addition, the dynamic balance of the shaft 1 is kept on the basis of detected displacement.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the rotation of a slicing machine or the like which is equipped with an outer peripheral blade grindstone or a cup grindstone at one end of a rotary spindle to perform, for example, groove machining, chip division machining or mirror surface machining when manufacturing a magnetic head. Regarding processing machines.

[0002]

2. Description of the Related Art Generally, in manufacturing a magnetic head,
Winding groove grooving, track width groove processing, mirror surface processing, chip division processing, etc. are performed, and these processing are done mechanically by a slicing machine with an outer peripheral edge grindstone or cup grindstone attached to one end of the rotating spindle. ing.

In the conventional slicing machine, as shown in FIG. 4, an air spindle rotor shaft 21 is rotatably housed in a spindle housing 22 with one end thereof exposed, and the air spindle rotor shaft 21 is attached to one end of the air spindle rotor shaft 21. ,
A peripheral edge grindstone 23 is attached. A rotor 24 is provided at the rear of the air spindle rotor shaft 21, and a stator 25 is provided on the inner surface of the housing 22 at a position facing the rotor 24. By the rotor 24 and the stator 25, the air spindle rotor shaft 2
1 rotates at a predetermined rotation speed. The housing 22 has a rear part housed in an M / C column 27 fixed to a base 26.

On the other hand, the work W is fixed on a slide table 29 which is slidable with respect to the base 28 in the front-rear direction thereof, that is, in the direction perpendicular to the axis of the air spindle rotor shaft 21.

When the workpiece W fixed on the slide table 29 is to be grooved, for example, a motor (rotor 2) for rotationally driving the air spindle rotor shaft 21 is used.
4 and the stator 25), the outer peripheral blade grindstone 23 is rotated, and the slide table 29 is slid toward the grindstone 23.

By the way, when the work W is machined with high precision, if the air spindle rotor shaft 21 is subjected to unnecessary vibration, the grindstone 23 will be worn quickly and the machining width and the like will not be stable.

Therefore, conventionally, as shown in the figure, vibration detection pickups 30a and 30b are attached to the flange side and the motor side of the housing 22, respectively, and the vibrations of the air spindle rotor shaft 21 are picked up by these pickups 30a and 30b. Then, the unbalanced position and amount are calculated from this vibration waveform and phase to achieve dynamic balance. That is, based on the above calculation result, the protrusion amount of several balance screws concentrically arranged on the grindstone mounting flange 31 is changed to balance the dynamic balance of the air spindle rotor shaft 21.

[0008]

However, in the conventional slicing machine, the spindle housing 22 that rotatably accommodates the air spindle rotor shaft 21.
The vibration detection pickups 30a and 30b are attached to the above, and the dynamic balance of the air spindle rotor shaft 21 is made based on the detection results from these pickups 30a and 30b. However, in this method, the vibration of the housing 22 is small. That is, it was devised from the idea that the vibration of the air spindle rotor shaft 21 would be small,
This is not necessarily a good method in a slicing machine that requires high accuracy in rotation of the air spindle rotor shaft 21, such as when manufacturing a very small part such as a magnetic head.

This is because, in a slicing machine with high rotational accuracy, the housing 22 is
This is because the vibration of the air spindle rotor shaft 21 is large, but the phenomenon that the vibration of the air spindle rotor shaft 21 is large easily occurs. Wears quickly,
There is an inconvenience that the stability of the processing width is not improved.

Ideally, the air spindle rotor shaft 21
It is desirable to attach a pickup to one end of the shaft to directly read the vibration of the air spindle rotor shaft 21, but in reality, the pickup is exposed to grinding liquid and cannot be used, or the rotation of the grindstone 23 destroys the pickup itself. There is a risk that it will not be adopted.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a groove processing and a mirror surface processing which are performed when manufacturing a magnetic head, for example, which requires high accuracy. It is an object of the present invention to provide a rotary processing machine capable of improving the processing accuracy and extending the life of a processing tool such as a grindstone.

[0012]

According to the present invention, there is provided a rotary machining machine for machining a work W by mounting a required tool (peripheral blade grindstone 3) on one end of a rotary spindle 1.
Non-contact displacement sensors 16a and 16b for detecting the vibration of the rotary spindle 1 are provided near the other end of the.

Particularly, when there is a housing 2 which exposes one end of the rotary main shaft 1 and rotatably accommodates the rotary main shaft 1, the non-contact displacement sensor 16a near the other end of the rotary main shaft 1 in the housing 2. And 16b are provided.

[0014]

According to the above-described structure of the present invention, when there is a housing 2 which rotatably accommodates the rotary main shaft 1 by exposing the vicinity of the other end of the rotary main shaft 1, particularly one end of the rotary main shaft 1, A non-contact displacement sensor 16 for detecting the vibration of the rotary spindle 1 near the other end of the rotary spindle 1 in the housing 2.
Since a and 16b are provided, it is possible to directly observe the vibration state of the rotary spindle 1 by observing the displacement of the rear end of the rotary spindle 1.

Therefore, instead of estimating the vibration of the rotary main shaft 1 by observing the vibration of the housing 2 as in the conventional case, the vibration of the rotary main shaft 1 can be directly observed, and the dynamic balance of the rotary main shaft 1 can be accurately adjusted. be able to. As a result, the rotation accuracy of the rotary spindle 1 is improved, and it is possible to improve the processing accuracy in groove processing and mirror surface processing that are performed when manufacturing a magnetic head, for which high accuracy is required.
It is possible to extend the service life of processing tools such as grinding wheels.

[0016]

Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a configuration diagram showing a main part of a rotary processing machine according to the present embodiment, for example, a slicing machine used for groove processing and chip division processing in manufacturing a magnetic head.

In this slicing machine, an air spindle rotor shaft 1 is rotatably housed in a spindle housing 2 with one end exposed, and an outer peripheral grinding wheel 3 is attached to one end of the air spindle rotor shaft 1. ing. Also, at the rear of the air spindle rotor shaft 1,
A motor coil that constitutes the rotor 4 is wound, and a motor coil that constitutes the stator 5 is provided at a location on the inner surface of the housing 2 facing the rotor 4. By the rotor 4 and the stator 5, the air spindle rotor shaft 1
Rotates at a predetermined rotation speed. The housing 2 has a base 6
The rear part is accommodated in the M / C column 7 fixed to.

As shown in FIG. 2, the air spindle rotor shaft 1 is formed with a taper from one end 1a thereof to the radial bearing portion 8 to form a spindle taper portion 9. As shown in FIG. The outer peripheral blade grindstone 3 is attached to the groove 9 by the grindstone mounting flange 10. At the other end of the air spindle rotor shaft 1, a spindle tail portion 11 is formed by a protruding portion that protrudes rearward from the rear end of the rotor 4. Further, a thrust bearing portion 12 is arranged between the radial bearing portion 8 and the rotor 4.

On the other hand, the workpiece W, which is a workpiece, is slidable in the front-back direction of the base 13 having, for example, a V-shaped guide surface a, that is, in the direction perpendicular to the air spindle rotor shaft 1. It is fixed on the slide table 14. The slide table 14 slides by a known slide mechanism (for example, a feed screw mechanism or the like).

However, in this example, as shown in an enlarged view of the main part in FIG. 3, the motor rear cover 15 detachably attached to the rear part of the spindle housing 2 and the rear side part of the housing 2 are respectively provided with static electricity. Non-contact displacement sensors 16a and 16b such as capacitance conversion type displacement sensors are attached and configured.

In particular, one of the non-contact displacement sensors 16a is
The detection surface is attached so as to face the rear surface of the spindle tail portion 11, and the other non-contact displacement sensor 16b is attached so that the detection surface faces the side surface of the spindle tail portion 11.

In order to balance the dynamics of the air spindle rotor shaft 1, first, the air spindle rotor shaft 1
Is rotated at a predetermined rotation speed (processing speed), and the vibration of the air spindle rotor shaft 1 accompanying this rotation is read by the non-contact displacement sensors 16a and 16b. That is, the axial displacement of the spindle tail portion 11 is read by one of the non-contact displacement sensors 16a, and the other non-contact displacement sensor 16a is read.
The displacement of the spindle tail portion 11 in the direction perpendicular to the axis is read by b.

At this time, the non-contact displacement sensors 16a and 16a
The displacement data from 6b is displayed on a monitor, and the vibration direction of the air spindle rotor shaft 1 is determined by a known Lissajous waveform calculation. Then, based on the determined vibration direction, the protrusion amount of several balance screws concentrically arranged on the grindstone mounting flange 10 is changed to balance the dynamics of the air spindle rotor shaft 1 to obtain the air spindle rotor shaft. The vibration of 1 itself is reduced.

The displacement of the spindle tail portion 11 for this dynamic balancing is detected without moving the slide table 14 to which the work W is fixed. That is, the air spindle rotor shaft 1 is idled. Further, since the spindle tail portion 11 is an object of displacement detection by the non-contact displacement sensors 16a and 16b, it is preferable to finish the surface thereof with high accuracy.

When the workpiece W fixed on the slide table 14 is to be grooved, for example, a motor (rotor 4 and stator 5) for driving the air spindle rotor shaft 1 to rotate the outer peripheral blade 3 is used. And the slide table 14 is slid in the three directions of the grindstone.

In this case, a cutting load is applied to the grindstone 3 by processing the work W. Even during this processing, if the displacement of the spindle tail portion 11 is detected by the non-contact displacement sensors 16a and 16b, the above cutting load is applied. It can be quantitatively known, and can be effectively used for determining whether the sharpness of the grindstone 3 is deteriorated or dressing (dressing) time.

As described above, according to this embodiment, the non-contact displacement sensor 16a for detecting the displacement of the spindle tail portion 11 due to the vibration of the air spindle rotor shaft 1 is provided at the rear side portion of the motor rear cover 15 and the spindle housing 2. 1
Since 6b is provided, the vibration state of the air spindle rotor shaft 1 can be directly observed by observing the displacement of the rear end of the air spindle rotor shaft 1.

Therefore, instead of estimating the vibration of the air spindle rotor shaft 1 by observing the vibration of the housing 2 as in the conventional case, the vibration of the air spindle rotor shaft 1 can be directly observed, and the motion of the air spindle rotor shaft 1 can be seen. Balance can be taken with high precision. As a result, the rotation accuracy of the air spindle rotor shaft 1 is improved, and it is possible to improve the processing accuracy in groove processing and mirror surface processing that are performed when, for example, a magnetic head is required to have high accuracy. It is possible to extend the life of the processing tool such as the grindstone 3.

Further, since the air spindle rotor shaft 1 can be rotated with good balance, the grindstone 3
Therefore, it is possible to improve the working efficiency and prevent accidents such as seizure of the air spindle rotor shaft 1.

In the above example, the vibration direction of the air spindle rotor shaft is determined based on the displacement data from the two non-contact displacement sensors. However, which non-contact displacement sensor should be used depends on the machining mode. Good. For example, when a V-shaped groove or a U-shaped groove is formed on the work W, since vibration in the axial direction becomes particularly large, one of the non-contact displacement sensors is used to monitor the vibration state, and the work W is chipped. In the division processing, since vibration in the direction perpendicular to the axis becomes particularly large, the other non-contact displacement sensor is used to monitor the vibration state.

In the processing of the work W, when the surface accuracy is not so required, the non-contact displacement sensor 1
By feeding back the displacement data from 6a and 16b to the rotation system (control circuit) of the air spindle rotor shaft 1, the rotation speed of the air spindle rotor shaft 1 is changed to reduce the vibration of the air spindle rotor shaft 1. May be.

[0032]

According to the rotary machining machine of the present invention, it is possible to improve the machining accuracy in the groove machining and the mirror surface machining which are required when high precision is required, for example, when manufacturing a magnetic head. It is possible to extend the service life of processing tools such as grinding wheels.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a main part of a slicing machine according to an embodiment.

FIG. 2 is a side view showing a configuration of an air spindle rotor shaft according to the present embodiment.

FIG. 3 is an enlarged view showing a main part of the slicing machine according to the present embodiment.

FIG. 4 is a configuration diagram showing a main part of a slicing machine according to a conventional example.

[Explanation of symbols]

1 Air spindle rotor shaft 2 spindle housing 3 outer peripheral grinding wheel 4 rotor 5 stator 6,13 base 7 M / C column 10 Grindstone mounting flange 14 slide table 15 Motor rear cover 16a, 16b Non-contact displacement sensor

Claims (2)

[Claims] 1. A rotary machining machine for machining a workpiece by attaching a required tool to one end of a rotary spindle, and a non-contact displacement sensor for detecting vibration of the rotary spindle is provided near the other end of the rotary spindle. A rotary processing machine characterized by 2. A shaft housing that exposes one end of the rotary main shaft and rotatably accommodates the rotary main shaft, and the non-contact displacement sensor is provided near the other end side of the rotary main shaft in the housing. The rotary processing machine according to claim 1, wherein