JPH1170453A - Polishing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate a supply of polish liquid inbetween elastic polishers and a work maching surface by providing the elastic polishers with elastic films having internal pressure and by arranging a plurality of elastic polishers in such a state as divided into several places in a substrate. SOLUTION: A polishing tool 1 for polishing the top face of a work 3 is constituted of a polishing dish 17 or a substrate having rigidity and three elastic polishers 19 arranged in its bottom face. The three elastic polishers 19 are arranged in such a state as being sorted on the circumference. The elastic polishers 19 are divided into a plural number and brought in contact with the work 3 in a small area so that the superior fitting capability is provided between the work 3 and the elastic polishers 19. The displacement can be suppressed to that per a polisher so that the unevenness in the repulsire force of the elastic polisher 19 increased by the displacement can be suppressed. Namely, this polisher 19 can be in contact with the work at the same pressure at all times, no matter where it is placed on the nonspherical face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing tool for finish-polishing an optical component or a curved surface of a mold. In particular, it relates to a polishing tool having an elastic polisher suitable for polishing an aspheric surface.

[0002]

2. Description of the Related Art The prior art will be described by taking aspherical polishing of an optical component as an example. 2. Description of the Related Art In recent years, lenses and mirrors having an aspheric refraction surface or reflection surface have been frequently used for correcting aberrations of an optical system. The polishing of the aspherical surface requires a special technique, unlike the polishing of the spherical surface. In the case of spherical polishing, a mother tool having a spherical processed surface and a workpiece having substantially the same spherical processed surface are relatively rotated and rotated.
Polishing can be performed by rubbing while swinging. However, in the case of an aspherical surface, when the mother and the workpiece are rocked due to their geometric properties, the processed surface and the processed surface do not match in the first place. It is possible. On the other hand, if the tool and the workpiece are rotated relative to each other with the axes aligned, the relative speed between the tool and the workpiece near the axis cannot be obtained, and machining is performed in the same part. I can't.

[0003] Therefore, for polishing an aspherical surface, an elastic polisher having a machined surface following the basic shape of the surface to be machined is usually prepared, and the polisher and the workpiece are pressed while the elastic polisher is pressed against the surface to be machined. Is used to relatively rotate and oscillate. Sometimes, when it is necessary to make the polishing removal amount uniform over the entire surface to be processed, it is necessary that the processed surface of the elastic polisher contacts the surface to be processed with a uniform pressure. The polishing here has a small meaning of actively creating the shape of the surface to be processed, and is mainly intended to smooth the unevenness of the surface to be processed.

FIG. 4 is a side sectional view showing a conventional aspherical polishing tool having an elastic polisher and a state in which polishing is performed using the tool. In this figure, the upper surface (working surface 303a) of the workpiece 303 is polished using the polishing tool 301. The polishing tool 301 includes a polishing plate 317, which is a rigid substrate, and an elastic polisher 319 extending on the lower surface thereof.

The elastic polisher 319 is connected to the inner rubber bag 32.
3 and an outer polisher 321. The rubber bag 323 is an airtight balloon-like object, and the periphery thereof is airtightly fixed to the lower end of the polishing plate 317. Polisher 3
21 is a film of urethane foam or the like. Polisher 321
Holds the polishing liquid supplied from the nozzle 307 on its surface, and is pressed against and rubbed against the surface to be processed 303a. Air pressure is supplied to the inside of the rubber bag 323,
The pressure is applied as a polishing pressure between the surface of the polisher 321 and the processing surface 303a via the rubber bag 323.
In addition, since the pressure of the fluid existing in one space is basically the same according to Pascal's law, the polishing pressure is the same in each part.

[0006] The polishing plate 317 is a rigid disk-shaped object made of cast iron or the like. An elastic polisher mounting portion 318 projecting downward in a ring shape is provided on the periphery of the polishing plate 317. The periphery of the elastic polisher 319 is sandwiched and fixed to the same portion 318 (actually, FIG.
It has a structure like)

At the center of the upper surface of the polishing plate 317, the convex portion 31 is provided.
5 are provided so as to protrude upward. Convex part 315
A core hole 315a is dug in the center of the upper surface of the.
The spherical end 313 at the lower end of the upper shaft 311 is provided in the hole 315a.
Is in contact. The polishing plate 317 is linked to the rotation of the workpiece 303 about the lower shaft 331, and the upper shaft 311.
, And is forcibly traversed (oscillated) right and left in the figure by the upper shaft 311.

The central projection 315 is hollow, and has a pneumatic inlet 317e on one side. From the pneumatic inlet 317e, the polishing plate 317 and the elastic polisher 31
9, the elastic polisher 319 is pushed by the air pressure to protrude downward as described above, and the workpiece 3
03 is pressed. A polishing liquid nozzle 307 is arranged on the side of the polishing tool 301, and a polishing liquid is supplied from between the polishing liquid nozzle 307 and the elastic polisher 319 to the surface to be processed 303a.

The workpiece 303 is attached on a work plate 305. The work plate 305 rotates around a lower shaft 331 projecting from the center of the lower surface. The lower shaft 331 may be, for example, a lower shaft of a general Oscar-type polishing machine. The workpiece 303 also rotates at the same peripheral speed as the workpiece plate 305 rotates. The elastic polisher 319 is pressed against the upper surface 303a of the workpiece 303 as described above.

[0010] In this polishing process, the work surface 303
Processing is performed while adjusting the number of rotations of the workpiece 303, the width and position of the polishing tool 301, and the moving speed so that the polishing removal amount a becomes uniform over the entire surface 303a.

[0011]

The above-mentioned conventional polishing tool or machining has the following problems. (1) Since the elastic polisher of the conventional polishing tool is an integral body and almost all of its lower surface is in close contact with the surface to be processed 303a, it is difficult for the polishing liquid to be supplied between the elastic polisher and the surface to be processed.

(2) For the same reason as in the above (1), there is a difference in the amount of partial expansion and contraction of each part of the elastic polisher depending on the shape of the surface to be processed. As a result, the elastic repulsion force of the elastic polisher itself is different in each part, and even though the air pressure in the elastic polisher is uniform, the polishing pressure becomes uneven, making it difficult to perform uniform polishing. .

(3) For the same reason as in the above (1) and because the restraint of the elastic polisher in the left-right direction is weak, the elastic polisher is caused by the frictional force between the elastic polisher and the surface to be processed when the polishing tool 301 moves left and right. Was easily deformed in such a way as to shift sideways. For this reason, similarly to the above (2), the polishing pressure was uneven. Also, vibration may occur between the workpiece and the elastic polisher, causing undulation on the workpiece surface.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a polishing tool which can easily supply a polishing liquid between an elastic polisher and a surface to be processed. It is another object of the present invention to provide a polishing tool in which the processing pressure between the elastic polisher and the surface to be processed is uniform, that is, both have good fitting properties and are less likely to cause polishing unevenness.

[0015]

In order to solve the above-mentioned problems, a polishing tool according to a first aspect of the present invention is a polishing tool comprising: a base; and an elastic polisher mounted on the base and pressed against a workpiece. The elastic polisher is provided with an elastic film having an internal pressure, and a plurality of elastic polishers are dividedly arranged on the base.

Since the polishing liquid can be supplied from between the divided elastic polishers, the polishing liquid easily flows between the surface to be processed and the elastic polisher. In addition, since the elastic polisher is divided and subdivided, when the elastic polisher is pressed against the surface to be processed, the amount of unevenness in each individual elastic polisher is reduced. As a result, the difference in the amount of expansion and contraction of the elastic polisher and the difference in the repulsion force are reduced, and polishing unevenness can be suppressed.

Further, a polishing tool according to a second aspect of the present invention comprises:
A polishing tool comprising: a base; and an elastic polisher attached to the base, the elastic polisher being pressed against a workpiece. The polishing polisher includes an elastic film having an internal pressure; A polishing liquid is supplied into the film, and the polishing liquid is supplied between the polisher and the workpiece through the hole.
In this case, since the polishing liquid can be directly supplied between the elastic polisher and the surface to be processed, it becomes easier to supply the polishing liquid.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a polishing tool according to a second aspect of the present invention, it is preferable that a plurality of recesses are formed in the base, and the elastic polisher is disposed in the recesses. Alternatively, the base is formed of a hollow body, the elastic polisher is disposed in the hollow portion, and a hole is formed in the base for communicating the hollow portion with the outside, and the elastic polisher is moved out of the hole. Preferably, it is overhanging. In this case, deformation and vibration of the elastic polisher in the swing direction can be suppressed, and uneven polishing can be suppressed.

Hereinafter, description will be made with reference to the drawings. FIG.
FIG. 1 is a view showing a polishing tool according to one embodiment of the present invention and a state in which polishing is performed using the polishing tool. (A) is a side sectional view, and (B) is a bottom view. In this figure, the upper surface (work surface 3a) of the workpiece 3 is polished using the polishing tool 1. The polishing tool 1 is a polishing plate 1 that is a rigid substrate.
7 and three elastic polishers 19 arranged on the lower surface thereof. The three elastic polishers 19 are distributed on the circumference as shown in FIG. The plane area occupied by the entire three elastic polishers 19 is preferably 60 to 80% or more of the area of the polishing plate 17. In addition, as a method of attaching the elastic polisher 19 to the polishing plate 17,
Adhesion with an epoxy adhesive or the like can be given.

The elastic polisher 19 is used for the inner rubber bag 2.
3 and the outer polisher 21 are bonded together. The rubber bag 23 is an airtight balloon-like object. The polisher 21
It is a film of urethane foam or the like. The polisher 21 holds the polishing liquid supplied from the nozzle 7 on its surface, and is pressed against and rubbed against the work surface 3a. Air pressure is supplied to the inside 25 of the rubber bag 23, and the pressure is applied as a polishing pressure between the surface of the polisher 21 and the work surface 3 a via the rubber bag 23. The diameter of the polishing plate 17 is preferably substantially the same as the diameter of the workpiece 3 when performing uniform processing. In order to arrange the profile of the work surface in the order of several μm (actively create), 1/3 to 2/3 of the work
The degree is preferred. The hollow portion 2 of each elastic polisher 19
5 is connected to a pipe of the same system (not shown) and is inflated at the same internal pressure.

The workpiece 3 is stuck on a work plate 5. The work plate 5 rotates around a lower shaft 31 projecting from the center of the lower surface. The lower shaft 31 may be, for example, a lower shaft of a general Oscar-type polishing machine.
The workpiece 3 also rotates at the same peripheral speed as the workpiece plate 5 rotates. The elastic polisher 19 is pressed against the upper surface 3a of the workpiece 3 as described above.

A polishing liquid supply nozzle 7 is provided beside the polishing tool 1.
The polishing liquid is sprayed and supplied from between the elastic polishers 19 toward the center of the polishing tool 1 as shown in FIG. The polishing tool 1 also rotates together with the frictional force with the rotation of the workpiece 3 side.
The polishing liquid is supplied almost uniformly between them. In this polishing process, the number of rotations of the workpiece 3 and the width and position of the polishing tool 1 are adjusted so that the removal amount of the workpiece surface 3a is uniform over the entire workpiece surface 3a. Processing while doing.

As described above, in the aspherical polishing tool of this embodiment, the elastic polisher is divided into a plurality of pieces and comes into contact with the workpiece with a small area. For this reason, the fitting property between the workpiece and the elastic polisher is excellent, and the amount of deformation can be suppressed per polishing polisher, so that the unevenness of the resilience of the elastic polisher, which increases with the amount of deformation, can be suppressed. In other words, any part of the aspherical surface can always contact the workpiece with equal pressure.

FIG. 2 is a side sectional view showing an aspherical polishing tool having an elastic polisher according to another embodiment of the present invention and a state in which polishing is performed using the tool. In the same figure, the parts indicated by the reference numerals obtained by adding 100 to the reference numerals in FIG. 1 indicate the same parts and parts. The feature of this embodiment is that a plurality of recesses 117a are formed on the lower surface of the polishing dish 117, and one elastic polisher 119 is arranged in each of the recesses 117a. The depth of the recess 117 a is approximately １ ／ to の of the thickness of the elastic polisher 119. By arranging the elastic polisher so as to be half-buried in the polishing plate, lateral deformation of the elastic polisher can be suppressed, and uneven polishing can be suppressed.

FIG. 3 is a side sectional view showing an aspherical polishing tool having an elastic polisher according to another embodiment of the present invention and a state in which polishing is performed using the tool. In the same figure, the parts indicated by the reference numbers obtained by adding 200 to the reference numbers in FIG. 1 indicate the same parts and parts. The feature of the polishing tool of this embodiment is that the base 217 is formed of a hollow body and the elastic polisher 2
19 is disposed in the hollow portion, and a hole 217c for communicating the hollow portion 217d with the outside is formed in the base 217, and the elastic polisher 219 protrudes outward from the hole.

That is, the polishing plate 217 has an upper plate 217a.
And a lower plate 217b disposed below the plate 217a at a fixed distance from the plate 217a.
17d. The lower plate 217b is, specifically, a disk having the same curvature (work surface and approximate curvature) as the upper plate 217a, and is screwed to the periphery of the upper plate 217a. The lower plate 217b has a plurality of holes 217c. The elastic polisher 219 protrudes downward from the hole 217c.

The elastic polisher 219 has the same structure as the conventional elastic polisher shown in FIG. 4 (the illustration of the double membrane structure is omitted). The peripheral edge of the elastic polisher 219 is sandwiched between the lower plate 217b and the upper plate 217a of the polishing plate 217. On the back side (upper side) of this elastic polisher 219,
Air pressure is supplied. Under this air pressure, the elastic polisher 219 protrudes downward from the hole 217c of the lower plate 217b, and is pressed against the surface 203a of the workpiece 203. The protrusion amount is, for example, 2 to 5 mm. The central projection 21 on the upper plate 217a of the polishing plate 217
5 and the structure of the pneumatic supply port 317e are the same as those of the prior art shown in FIG.

In the polishing tool of the embodiment shown in FIG. 3, the elastic polisher is also restrained in the swinging direction by the polishing plate, so that deformation due to frictional force with the workpiece can be suppressed. As a result, the movement of the oscillating shaft of the polishing machine can be transmitted to the workpiece, and a desired polishing amount can be obtained. In addition, since the vibration generated between the workpiece and the polishing polisher, which occurs when this measure is not taken, can also be suppressed, it is possible to suppress the occurrence of undulation on the polished surface.

A modification of the embodiment shown in FIG. 3 will be described.
In this example, the elastic polisher 219 has many small holes (diameter is 0.1 to 0.2 mm, for example). And the polishing plate 21
The polishing liquid is supplied to the inside of the chamber 7 instead of the air pressure. The supplied polishing liquid is ejected from a small hole of the elastic polisher 219 and supplied to the polishing surface. In this case, the polishing liquid can be reliably supplied to the polishing surface.

[0030]

As is clear from the above description, in the present invention, the polishing polisher having an internal pressure is subdivided to promote the flow of the polishing liquid to the polishing surface and to reduce the polishing polisher to the workpiece. Can be improved. Further, by using an elastic body having fine holes, by spraying a polishing liquid from the fine holes,
Further, it is possible to promote the flow of the polishing liquid to the polishing surface.

[Brief description of the drawings]

FIG. 1 is a view showing a polishing tool according to an embodiment of the present invention and a state in which polishing is performed using the polishing tool. (A) is a side sectional view, and (B) is a bottom view of the polishing tool.

FIG. 2 is a side sectional view showing an aspheric polishing tool having an elastic polisher according to another embodiment of the present invention and a state in which polishing is performed using the polishing tool.

FIG. 3 is a side sectional view showing an aspheric polishing tool having an elastic polisher according to another embodiment of the present invention and a state in which polishing is performed using the polishing tool.

FIG. 4 is a side sectional view showing a conventional aspheric polishing tool having an elastic polisher and a state in which polishing is performed using the tool.

[Explanation of symbols]

1 Polishing Tool 3 Workpiece 5 Work Dish 7 Polishing Liquid Nozzle 11 Upper Shaft 13 Spherical End 15 Central Convex 17 Polishing Dish 19 Elastic Polisher 21 Polisher 23 Rubber Bag 25 Hollow 31 Lower Shaft 117a Concave 217a Upper Plate 217b Lower Plate 217c hole 217d hollow part 217e air supply port 318 elastic polisher mounting part

Claims (4)

[Claims] 1. A substrate, and attached to the substrate.
A polishing tool comprising: an elastic polisher pressed against a workpiece; and a polishing tool comprising: an elastic polisher having a film of an elastic material having an internal pressure; A polishing tool characterized by being arranged. 2. The polishing tool according to claim 1, wherein a plurality of recesses are formed in the base, and the elastic polisher is arranged in the recesses. 3. The base body comprises a hollow body, the elastic polisher is disposed in the hollow part, and a hole is formed in the base body for communicating the hollow part with the outside. 2. The polishing tool according to claim 1, wherein the polishing tool protrudes outward from the hole. 4. A substrate, mounted on the substrate,
A polishing tool comprising: an elastic polisher pressed against a workpiece; said elastic polisher comprising an elastic film having an internal pressure, wherein said elastic film has minute holes; A polishing tool is supplied with a polishing liquid, and the polishing liquid is supplied between the polisher and the workpiece through the hole.