JP2002178248A - Polishing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly precisely polish a work while keeping a polishing load to the work constant. SOLUTION: This polishing device polishes the machining surface of the work 52 by a polisher 58a. This polishing device is provided with an X-axis mechanism part 54 moving the work 52 in the X-axis direction, a Y-axis mechanism part 55 moving the work 52 in the Y-axis direction, a Z-axis mechanism part 53 moving the work 52 in the Z-axis direction, an A-axis mechanism part 56 rotating the work 52 about the X axis, a B-axis mechanism part 57 rotating the work 52 about the Y axis, and a control means controlling the X-axis mechanism part 54, the Y-axis mechanism part 55, the Z-axis mechanism part 53, the A-axis mechanism part 56, and the B-axis mechanism part 57 so that a contact point between the polisher and the work in the polishing is positioned in the X axis or near the X axis and positioned in the Y axis or near the Y axis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing apparatus for precisely polishing an optical curved surface of an optical element such as a lens or a prism or a processing curved surface such as a mold for molding the optical element.

[0002]

2. Description of the Related Art FIGS. 8 and 9 show a process for polishing a work surface of a work as described above.
8 shows a conventional polishing apparatus described in Japanese Patent Application Publication No. 8 (JP-A-8).

In this polishing apparatus, a Y-axis table 11 and an X-axis table 12 that move in the Y-axis direction are placed on a base 10 in order, and a B-axis positioning mechanism that rotates on the X-axis table 12 around the Y-axis. A section 13 is provided, and an A-axis positioning mechanism section 14 that rotates about the X-axis is provided on the B-axis positioning mechanism section 13. The work 15 is mounted on a work table 16 mounted on the A-axis positioning mechanism 14 and processed.

On the other hand, a tool 17 for performing a polishing process is mounted on a Z-axis positioning mechanism 18. The Z-axis positioning mechanism 18 is mounted on a column 19 erected on the base 10 as shown in FIG. 9, and can be moved up and down by driving a motor 20 mounted on the column 19.
The Z-axis positioning mechanism 18 includes a spindle 22 that rotates the tool 17 by driving a motor 21.
The spindle 22 is connected to a piston rod 24 of a cylinder 23. The cylinder 23 is controlled so that a constant air pressure is supplied.
Numeral 7 moves up and down along the curved surface of the work 15 at a constant pressure.

[0005] In this apparatus, in a state where the tip of the tool 17 is in contact with the surface of the work 15 at a predetermined pressure, four directions of X, Y, A, and B directions are determined based on processing data calculated from the shape of the work 17. By controlling, the tool 17 and the work 15 are relatively positioned, and the polishing is performed by making the rotation axis of the tool 17 coincide with the normal direction at the processing point of the work. In this case, in the Z direction, the work is made to follow the curved surface of the work 15 by the pressing mechanism including the cylinder 23.

[0006]

However, in the above-mentioned conventional polishing apparatus, the directions to be controlled during the polishing process are X,
There are four axes of Y, A, and B, and the pressing mechanism moves in the Z direction. Therefore, during the polishing, the contact point between the tool 17 and the work 15 moves in the Z direction, and by this movement, it is difficult to keep the polishing load applied to the work 15 by the tool 17 constant, and it is highly accurate. There is a problem that polishing is difficult.

The center of rotation of the A-axis positioning mechanism 14 or the B-axis positioning mechanism 13 and the tool 17
When the A-axis positioning mechanism unit 14 or the B-axis positioning mechanism unit 13 is rotated during the polishing of the work, since the polishing point in contact with No. 5 does not match, the target polishing point at the next moment Shifts in the X-axis, Y-axis, or Z-axis directions. Therefore, in order to apply the polishing load by the tool 17 in the normal direction at the target polishing point, the A-axis positioning mechanism 14 or the B-axis positioning mechanism 1
It is necessary to correct the moving amount in the X direction or the Y direction generated by the rotation of the third rotation, and the moving speed in the X direction or the Y direction can be reduced by rotating the A-axis positioning mechanism unit 14 or the B-axis positioning mechanism unit 13. Tool 17
It is difficult to maintain a constant relative speed between the workpiece and the processing surface of the workpiece 15, that is, a so-called feed speed, and the amount of information increases.
There is also a problem that the calculation at the time of processing becomes complicated.

The present invention has been made in consideration of such conventional problems, and can maintain a constant polishing load on a work, thereby enabling the work to be polished with high precision. An object of the present invention is to provide a polishing apparatus.

[0009]

According to a first aspect of the present invention, there is provided a polishing apparatus for polishing a work surface of a work by using a polisher, wherein an X-axis mechanism for moving the work in the X-axis direction; A Y-axis mechanism for moving in the direction,
A Z-axis mechanism for moving the work in the Z-axis direction, an A-axis mechanism for turning the work about the X-axis, a B-axis mechanism for turning the work about the Y-axis,
The X-axis mechanism unit, the Y-axis mechanism unit, the Z-axis mechanism unit, A so that the contact point between the polisher and the workpiece during the polishing process is located near the X-axis or the X-axis and near the Y-axis or the Y-axis.
A control mechanism for controlling the shaft mechanism and the B-axis mechanism is provided.

In the present invention, the X-axis mechanism, the Y-axis mechanism,
By controlling the Z-axis mechanism section, the A-axis mechanism section and the B-axis mechanism section, the point of contact between the polisher and the work is always located on or near the X-axis when polishing the work,
In addition, since the polisher is positioned on or near the Y axis at the contact point, the pressing direction of the polisher is oriented in the normal direction of the work surface of the work, and the polishing load on the work can be kept constant. Therefore, the work surface of the work can be polished with high precision.

According to a second aspect of the present invention, in the first aspect, the X-axis mechanism, the Y-axis mechanism, the Z-axis mechanism,
The shaft mechanism and the B-axis mechanism are assembled in a stacked state.

[0012] By assembling all the mechanical parts in a stacked state in this manner, the apparatus can be made compact and the occupied area for installation can be reduced.

According to a third aspect of the present invention, in the first or second aspect, the control means matches or substantially matches a polishing load from the polisher to the work with a normal direction of a work surface of the work. The A-axis mechanism and the B-axis mechanism are controlled as described above.

According to the present invention, the pressing direction of the polisher is directed to the normal direction of the work surface of the work. For this reason, there is no dispersion of the polishing load of the polisher at the contact point, and the processing surface of the work can be polished with a constant pressure, and highly accurate polishing can be performed.

A fourth aspect of the present invention is the invention according to any one of the first to third aspects, further comprising vibration means for swinging the polisher at a point of contact with a workpiece. I do.

According to the present invention, the polisher swings during the polishing of the work, so that the processed surface of the work can be polished in a wide range.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments shown in the drawings. In each of the embodiments, the same members are assigned the same reference numerals to correspond to each other.

(Embodiment 1) FIG. 1 is an overall perspective view of Embodiment 1 of the present invention, in which a B-axis mechanism 57 and an A-axis mechanism are mounted on a base 51 supported on a frame or the like (not shown). Part 5
6, Y-axis mechanism 55, X-axis mechanism 54, Z-axis mechanism 53
Are sequentially assembled in a stacked state.

The Z-axis mechanism 53 is a mechanism that reciprocates in the Z direction, and the work 52 is fixedly supported on the Z-axis mechanism 53. The X-axis mechanism 54 is a mechanism that reciprocates in the X direction. The Z-axis mechanism 53 is fixed on a table 54 a of the X-axis mechanism 54, and the main body 5 of the X-axis mechanism 54.
4b is fixed on the Y-axis mechanism 55. The Y-axis mechanism 55 is a mechanism that reciprocates in the Y direction, and the X-axis mechanism 54 is fixed to the table 55a.

The main body 55b of the Y-axis mechanism 55 is fixed on the A-axis mechanism 56. The A-axis mechanism 56 is a mechanism that rotates around the X axis, and the Y-axis mechanism 55 is fixed to the table 56a. In such a stacked state, when the A-axis mechanism 56 is driven, the Y-axis mechanism 55, X
The shaft mechanism 54 and the Z-axis mechanism 53 pivot in the same direction, whereby the workpiece 52 pivots about the X-axis.

The main body 56b of the A-axis mechanism 56 is fixed on the B-axis mechanism 57. The B-axis mechanism 57 is a mechanism that rotates around the Y-axis, and the A-axis mechanism 56 is fixed to the table 57a. The main body 57b of the B-axis mechanism 57 is fixed on the base 51. In such a structure, when the B-axis mechanism 57 is driven, the A-axis mechanism 56,
The Y-axis mechanism 55, the X-axis mechanism 54, and the Z-axis mechanism 53 pivot in the same direction, whereby the workpiece 52 pivots around the Y-axis.

A polisher unit 58 for polishing the work 52 includes a polisher unit main body 58c having a built-in polisher motor (not shown), a polisher shaft 58b connected to the polisher motor, and a tip of the polisher shaft 58b. And an attached polisher 58a.
The polisher 58a is rotated by driving the polisher motor. The polisher motor is connected to a controller (not shown), and the number of revolutions of the polisher 58a is controlled by a program prepared in advance.

A support bracket 61 is erected on the base 51, and a polisher unit 58 is attached to a connecting arm 59 extending from the support bracket 61. In this embodiment, an air slider 80 is provided between the connecting arm 59 and the polisher unit 58, which can move a small distance in the Z direction. The air slider 60 is connected to an air source (not shown) so that the force for pressing the polisher 58a against the workpiece 52, that is, the polishing load, can be arbitrarily set by controlling the air pressure.

The B-axis mechanism 57, the A-axis mechanism 56, the Y-axis mechanism 55, the X-axis mechanism 54, and the Z-axis mechanism 53 are controlled by a program prepared in advance by a controller (not shown). ing. Further, a device is selected such that the rotation centers of the A-axis mechanism 56 and the B-axis mechanism 57 coincide with each other at a position where the contact point between the polisher 58a and the work 52 is expected.

The control by the controller is such that the point of contact between the polisher 58a and the workpiece 52 during polishing is X
This is performed so as to be located near the axis or the X axis, and near the Y axis or the Y axis. In such control, the X-axis and the Y-axis, which are the centers of rotation of the A-axis mechanism 56 and the B-axis mechanism 57, can be orthogonal at the contact point between the polisher 58a and the work 52. It should be noted that simultaneous control can be performed for each of the above-described mechanism units.

Next, the operation of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. Before the polishing process of the work 52,
The Z-axis mechanism 53 has moved downward, and the work 52 is at a position away from a contact point (hereinafter, a polishing point) between the polisher 58a and the work 52. An abrasive such as diamond slurry is applied to the surface of the work 52.

When a polishing start signal is input to the controller, the polisher motor in the polisher unit main body 58c starts rotating. The rotation of the polisher motor may be set to a constant speed rotation. In a case where it is necessary to increase the polishing amount to improve the roughness of a specific portion on the processing surface more than other portions, this is used. It is also possible to perform control such as increasing the number of rotations at a location.

When the polisher motor rotates, the polishing point moves to the polishing start point 31 shown in FIG.
The X, Y, Z, A, and B axis mechanisms are controlled. When the polisher 58a moves to the polishing start point 31, the air slider 60 operates to bring the polisher 58a into complete contact with the workpiece 52, thereby starting the polishing. In addition,
The air slider 60 generates a polishing load, and its setting is predetermined in consideration of various conditions such as the material of the work 52, the size and material of the polisher 58a, and the number of rotations. Similarly to the rotation of the polisher motor, the work 5
When it is desired to increase the polishing amount, for example, when it is desired to improve the roughness of the specific portion 2 compared to the other portions, it is also possible to perform control such as increasing the polishing load.

After the start of polishing, the polishing points are X, Y, Z,
Under the control of each of the A and B axis mechanism units, the workpiece 52 moves on the processing surface 52a as shown by the arrow in FIG. In other words, the polishing point moves on the processing surface 52a along the X direction from the polishing start point 31 in a direction away from the polishing start point 31.

FIGS. 3A to 3C show polishing points 32.
Shows the moving order of the. In this movement, the controller controls the polishing point 32 at the time of polishing to be located at the X axis or the vicinity of the X axis and at the Y axis or the vicinity of the Y axis. The X axis and the Y axis that are the rotation centers of the portion 57 are always
Are orthogonal. Thereby, at the polishing point 32,
The pressing direction of the polisher 58a is the processing surface 52a of the work 52.
Is polished in the direction of the normal 33 of FIG. Such control is performed by performing simultaneous four-axis control of the X-axis mechanism 54, the Z-axis mechanism 53, the B-axis mechanism 57, and the A-axis mechanism 56.

When the polishing point 32 reaches the position shown in FIG. 3C, the polishing point 32 moves a predetermined distance in the Y direction. After this movement, the polishing point 32 moves toward the polishing start point 31 along the processing surface 52a.
Thereafter, the same steps are repeated to reach the polishing end point 34 shown in FIG. Then, after the polishing end point 34 is reached, the polishing load by the air slider 60 is cut off, thereby finishing the polishing in the X-direction feed.

Next, in the polishing in the X direction, the polishing in the Y direction is performed with the polishing direction changed. FIG. 6 shows polishing in the Y-direction feed, in which the polishing point 32 moves on the processing surface 52a from the polishing start point 35 to the polishing end point 36.

FIGS. 5A to 5C show the movement of the polishing point 32 in the Y-direction feed polishing. Also in this movement, the control controller controls the polishing point 32 at the time of the polishing process so as to be located at the X axis or near the X axis and at the Y axis or near the Y axis. Therefore, A
The X-axis and the Y-axis, which are the rotation centers of the shaft mechanism 56 and the B-axis mechanism 57, are always orthogonal to the polishing point 32. Thus, at the polishing point 32, polishing is performed in a state where the pressing direction of the polisher 58a is oriented in the direction of the normal 33 of the processing surface 52a of the work 52. The above control is performed by performing simultaneous four-axis control of the Y-axis mechanism 55, the Z-axis mechanism 53, the B-axis mechanism 57, and the A-axis mechanism 56.

In FIGS. 2 and 4, the work 52 appears to be stationary without any movement.
This shows the relative movement between the polisher 58a and the work 52. By controlling the X, Y, Z, A and B axis mechanisms, the polisher 58a and the work 52 are programmed in advance. It is operated by.

By repeating the above-described polishing in the X-direction and the polishing in the Y-direction a predetermined number of times, an optical curved surface finished to a desired surface roughness can be obtained.

During the polishing, the workpiece 52
Judging from the situation described above, replacing the polisher 58a with a new one, further applying diamond slurry,
After wiping the diamond slurry used in the polishing step, an operation such as re-applying a new diamond slurry may be performed.

In such an embodiment, when the polishing point 32 is moved in the X direction in the X-direction feed polishing, X,
Simultaneous 4-axis control of Z, A, and B is performed, and when moving in the Y direction in polishing in the Y-direction feed, simultaneous movement of Y, Z, A, and B
Since axis control is performed, there is no need to perform simultaneous 5-axis control. For this reason, the amount of information is small, and calculation for control can be easily performed.

Even with the four-axis control, at the polishing point 32, the pressing direction of the polisher 58a is directed to the direction of the normal 33 of the processing surface 52a of the work 52.
The workpiece 52 can be polished with high precision by the rotation of a and the pressing of the polisher 58a.

Further, the B-axis mechanism 57 and the A-axis mechanism 5
6, Y-axis mechanism 55, X-axis mechanism 54, and Z-axis mechanism 5
Since all of the mechanical parts 3 are assembled in a stacked state, they are compact, and the occupied area for installation can be reduced.

(Embodiment 2) FIG. 6 shows Embodiment 2 of the present invention. In this embodiment, the X-axis mechanism 54, Y
Shaft mechanism 55, Z-axis mechanism 53, A-axis mechanism 56 and B
The shaft mechanism 57 is disposed in the same manner as in the first embodiment,
Control of these mechanisms is performed in the same manner as in the first embodiment.

In this embodiment, the polisher 58d of the polisher unit 58 has a disk shape. The disk-shaped polisher 58d polishes the processing surface of the work 52 at the outer peripheral portion 58e of the disk. The disc-shaped polisher 58 is rotated by driving a polisher motor (not shown) inside the polisher unit 58. In this embodiment, an air slider 58f is built in the polisher unit 58 instead of the air slider 60.

Polishing by the polishing apparatus of the present embodiment is the same as that of the polishing apparatus of the first embodiment except that the processing surface of the work 52 is processed by the outer peripheral portion 58e of the disk-shaped polisher 58d.

In this embodiment, as in the first embodiment, by controlling the pressing direction of the polisher 58d in contact with the processing surface of the work 52 so as to always face the normal direction of the processing surface, the polishing point Since the dispersion of the polishing load of the polisher 58d is eliminated, the processed surface of the work 52 can be polished with a constant pressure. Thereby, highly accurate polishing can be performed. In addition, since the polisher 58d has a disk shape and the outer peripheral portion 58e is a polishing surface, the peripheral speed of the polisher 58d can be increased. Thereby, efficient polishing can be performed.

(Embodiment 3) FIG. 7 shows Embodiment 3 of the present invention. Also in this embodiment, the X-axis mechanism 5
4. Y-axis mechanism 55, Z-axis mechanism 53, A-axis mechanism 56
The B-axis mechanism 57 is arranged in the same manner as in the first embodiment, and the control of these mechanisms is performed in the same manner as in the first embodiment.

In this embodiment, the polisher unit 5
Eighth polisher 58g has a cylindrical shape. An elastic body 58h is attached to a side of the cylindrical polisher 58g that contacts the work 52. Elastic body 58h
For example, a resin such as polyurethane is used.

Further, a vibration device 62 is arranged between the polisher unit 58 and the air slider 60. The vibration device 62 is connected to the connection arm 59 via the air slider 60, and the vibration causes the polisher 58g to swing on a tangent plane at the polishing point.

In the polishing by the polishing apparatus of this embodiment, a swinging operation to the polishing surface by the vibration device 62 is added at the time of polishing, and polishing is performed except that the elastic body 58h contacts the work 52 to perform polishing. This is the same as the polishing apparatus according to the first embodiment. In this embodiment, the polisher 58g has a cylindrical shape, and the elastic body 58h attached to the polisher 58g has a polishing action surface. Polishing can be performed.

[0048]

According to the first aspect of the present invention, the point of contact between the polisher and the work is always located on or near the X axis, and is located on or near the Y axis. The pressure direction is oriented in the normal direction of the work surface of the work, the polishing load on the work can be kept constant, and the work surface of the work can be polished with high accuracy.

According to the second aspect of the present invention, in addition to having the effects of the first aspect of the present invention, it becomes compact and can be installed within a small occupied area.

According to the invention of claim 3, claims 1 and 2
In addition to the effect of the invention, the dispersion of the polishing load of the polisher at the contact point is eliminated, and the work surface of the work can be polished with a constant pressure, so that highly accurate polishing can be performed.

According to the fourth aspect of the invention, in addition to having the effects of the first to third aspects, the work surface of the work can be polished in a wide range.

[Brief description of the drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

FIG. 2 is a perspective view showing polishing in the X-direction feed.

3 (a) to 3 (c) are side views from the direction of arrow D in FIG. 2 for explaining the operation in polishing in the X-direction feed.

FIG. 4 is a perspective view showing polishing in the Y-direction feed.

5 (a) to 5 (c) are side views of an arrow E in FIG. 4 for explaining an operation in polishing in the Y-direction feed.

FIG. 6 is a perspective view of Embodiment 2 of the present invention.

FIG. 7 is a perspective view of a third embodiment of the present invention.

FIG. 8 is a front view showing a conventional polishing apparatus.

FIG. 9 is a side view of FIG.

[Explanation of symbols]

 52 Work 53 Z-axis mechanism 54 X-axis mechanism 55 Y-axis mechanism 56 A-axis mechanism 57 B-axis mechanism 58 Polisher unit

Claims (4)

[Claims] 1. A polishing apparatus for polishing a work surface of a work with a polisher, an X-axis mechanism for moving the work in the X-axis direction, a Y-axis mechanism for moving the work in the Y-axis direction, A Z-axis mechanism for moving the workpiece in the Z-axis direction, an A-axis mechanism for rotating the workpiece about the X-axis, a B-axis mechanism for rotating the workpiece about the Y-axis, The X-axis mechanism section, the Y-axis mechanism section, the Z-axis mechanism section, and the A-axis mechanism so that the contact point between the polisher and the work is located at the X axis or near the X axis and at the Y axis or near the Y axis.
A polishing apparatus comprising: a shaft mechanism; and control means for controlling a B-axis mechanism. 2. The polishing apparatus according to claim 1, wherein the X-axis mechanism, the Y-axis mechanism, the Z-axis mechanism, the A-axis mechanism, and the B-axis mechanism are assembled in a stacked state. . 3. The control means controls the A-axis mechanism and the B-axis mechanism so that the polishing load from the polisher to the work coincides with or substantially coincides with the normal direction of the work surface of the work. 3. The polishing apparatus according to claim 1, wherein: 4. The polishing apparatus according to claim 1, further comprising a vibration means for oscillating the polisher at a contact point with a workpiece.