JPH0557589A - Polishing method - Google Patents

Abstract

PURPOSE:To improve the polishing accuracy by holding a sphere polishing tool, adding those of rocking, turning and vertical motion to a top face of a workpiece holding free of rotation as jetting out a fluid from the upside of a sphere, and making it so as to polish the workpiece along the ridgeline, in polishing for optical glass or the like. CONSTITUTION:A workpiece 9, whose top is of convexedly spherical form, is held on a disklike lense holder 6, and a sphere polishing tool 2 is set up on the top face with a tool holder 3. Then, this holder 3 is moved up and down, rotated and rocked in succession while a polishing solution containing cerium oxide or the like is fed out of a fluid feed hole 4, thus the workpiece is polished.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polishing optical glass or the like.

[0002]

2. Description of the Related Art As a document describing a conventional method for polishing a glass lens as described above, for example, JP-A-62-193761.
There is a gazette. The polishing method described in this publication is
While rotating the work piece, a portion of the spherical polishing tool having a high peripheral speed away from the central axis is pressed against the work piece to be polished, and the cycle of 0.
1 to 1 second Amplitude swings within 1 ^m / _m . As a result, the center of rotation of the polishing tool becomes a dead point and remains unpolished, and the center of rotation of the workpiece does not protrude and remain, so that even a workpiece having a concave surface can be easily polished. It is a polishing method.

[0003]

However, in the polishing method described in the above publication, the polishing tool 3 on the workpiece is rotationally polished at a position where the center of rotation is fixed at the θ angle, and thus the polishing tool 3 is used. Is always rotated at a constant circumferential surface position, which causes uneven wear on the spherical surface. That is, there is a problem in that when processing is performed with this unevenly worn spherical portion, the processing conditions change, and the lens processing surface cannot secure a desired surface accuracy.

The present invention has been made in view of the above-mentioned problems, and a high-precision workpiece can be highly processed by always polishing with a spherical polishing tool without causing uneven wear on the spherical surface. An object of the present invention is to provide a polishing method that can be manufactured with high quality.

[0005]

The concept of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a main part showing a cross section of a part of a polishing apparatus showing the concept of the present invention. The rotating shaft 8 is formed on the processing surface 7 of the circular workpiece 1 held and mounted on the disk-shaped holder 6 configured to rotate about the rotating shaft 8 in the direction indicated by the arrow. A cylindrical holder 3 is provided which is connected to a rotary shaft (not shown) which is configured to rotate by a driving means provided separately. A desired concave hemispherical surface 5 is formed on the lower end surface of the holder 3 corresponding to the holder 6, and the hemispherical surface 5 is formed.
Although not shown, a fluid supply hole 4 connected to a separately provided fluid supply means is formed at the center of the. Inside the hemispherical surface 5, a spherical body polishing tool 2 formed into a desired spherical body is arranged. That is, the hemispherical surface 5 of the holder 3 correspondingly arranged on the upper surface 7 of the rotating workpiece 1.
The spherical body polishing tool 2 inserted and disposed inside is separated from the hemispherical surface 5 by fluid supply (non-adhesive), and is rotatively oscillated to perform polishing to a free curved surface.

[0006]

In the polishing method having the above-mentioned structure, the spherical polishing tool 2 having a true spherical shape is floated on the upper surface 7 of the rotating workpiece 1 by supplying the fluid, and polishing is performed by rotation and rocking, so that the polishing is always stable. It is possible to perform polishing and obtain a processed surface with good surface accuracy.

When the spherical body polishing tool 2 is an abrasive (a tool containing abrasive grains), the processing surface 7 of the workpiece 1 is polished by the polishing blade. When the polishing tool 2 is a non-polishing agent, a polishing liquid (cerium oxide or the like) is interposed between the polishing tool 2 and the processed surface 7 of the workpiece 1 for polishing. Since the holder 3 is controlled so as to move up and down along the shape (curvature) of the processing surface, it is possible to perform processing while keeping the rolling property of the polishing tool of a true sphere constant and controlling the swing residence time. Therefore, a good processed surface can be obtained.

[0008]

Embodiment 1 An embodiment of the present invention will be described with reference to the drawings.
FIG. 2 is a front view showing a main part of a polishing method according to the first embodiment of the present invention and showing a part of the cross section. In the figure, the same members and configurations as those in FIG. 1 described above are designated by the same reference numerals, and the description thereof will be omitted.

A workpiece 9 having a convex spherical surface on its upper surface is held on the upper surface of a disk-shaped lens holder 6 configured to rotate by providing a rotary shaft 8 at the center of its lower surface. Although not shown, on the upper surface of the workpiece 9, there is disposed a columnar holder 3 which is configured to interlock with a drive mechanism and whose one end is attached to a rotary shaft and which vertically rotates and swings. A hemispherical concave portion 5 having a desired size is formed on the lower end surface of the holder 3, and a fluid provided outside, for example, an abrasive such as cerium oxide is contained in the center of the concave portion although not shown. Fluid supply hole 4 for passing the polishing liquid
(5 ^kg / cm ² or less) is drilled.

In the recess 5 formed on the lower end surface of the holder 3, a spherical polishing tool 2 for polishing the workpiece 9 is arranged. That is, by injecting from the fluid supply hole 4 containing cerium oxide or the like, the fluid is interposed between the spherical concave portion 5 and the polishing tool 2 of the spherical body in a non-contact state.

The polishing method of this embodiment having the above structure will be described. The spherical body polishing tool 2 is brought into contact with the processed surface of the workpiece 9 held on the holder 6 in advance. Subsequently, a fluid containing cerium oxide is jetted from the spherical surface 5 to the polishing tool 2 through the fluid supply hole 4 and the holder 6 and the holder 3 are driven respectively, so that the holder 6 moves in the direction indicated by the arrow and again in the holder. 3 also operates in the directions indicated by the arrows (rotation, swing, up and down). In the above description, the holder 3 swings around the center of curvature 0 of the workpiece 9 so as to freely roll the spherical body polishing tool 2 and control the fluid pressure and the retention of the spherical body polishing tool 2. Polished with the aid of an abrasive. That is, the holder 3 of the spherical body polishing tool 2 is controlled and rocked such that the holder 3 of the workpiece 1 has a shorter peripheral portion at a faster peripheral speed and a longer peripheral portion at a faster peripheral speed, and is polished.

In the above, the gap between the spherical surface 5 of the holder 3 and the spherical body polishing tool 2 is kept constant by lowering the wear amount of the spherical body polishing tool 2 on the holder 3 side so that there is little variation in processing conditions and good surface accuracy. Is obtained.

In the present embodiment, the material of the spherical body polishing tool 2 is not specified, but Teflon / acrylic / bakelite or the like is preferable in order to obtain a good polishing surface. The material of the optical lens that is the workpiece 9 may be quartz, fluorite, etc. in addition to the general crown-print system.

When the spherical body polishing tool 2 is a polishing tool containing abrasive grains such as diamond, carbon random, and cerium oxide, it is possible to perform polishing with water as a polishing liquid.

According to the present embodiment described above, the rolling of the spherical body polishing tool progresses into a true spherical shape due to the interaction of the rolling caused by the jetting of the fluid and the rolling caused by the rocking interaction, which causes uneven wear. Never. Therefore, the contact pressure on the processed surface does not change, so that a lens having a good polished surface can be obtained.

[0016]

[Embodiment 2] FIG. 3 is a front view showing a main portion of a second embodiment of the polishing method of the present invention and showing a part thereof in cross section. Note that, as in the first embodiment, the same members as those in FIGS. 1 and 2 are designated by the same reference numerals in the drawings, and the description thereof will be omitted.

As shown in FIG. 3, the difference between this embodiment and the above-mentioned first embodiment is that the shape of the processed lens, which is the workpiece, is different, and the other structures are exactly the same. That is, the workpiece 10 having a concave shape is integrally mounted on the upper surface of the holder 6, and the spherical body polishing tool 2 is disposed inside the concave spherical surface 5 of the holder 3 on the upper surface. .. Also holder 3
A fluid supply hole 4 is bored in the spherical center 5 of the above to spray the spherical body polishing tool 2. The polishing apparatus configured in this manner performs polishing by rotating the holder 6, rotating the holder 3, swinging, moving up and down, and ejecting fluid.

[0018]

[Embodiment 3] FIG. 4 is a front view showing a main portion of a third embodiment of the polishing method of the present invention, a part of which is shown in cross section. It should be noted that, as in the case of the above-described second embodiment, in FIGS.
The same members and the same configurations as those are denoted by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 4, the difference between this embodiment and the first embodiment is that in the first embodiment, the fluid containing the cerium oxide is fed from the fluid supply hole 4 of the holder 3 to the spherical body polishing tool 2 In the present embodiment, although not shown, air of 5 kg / cm ² or less is jetted to the spherical body polishing tool 2 by an air supply means, and the machining side surface thereof, that is, the spherical body polishing tool 2 and the workpiece. 9 is different from that of FIG. 9 in that an abrasive material supply pipe 11 is provided and a polishing liquid containing an abrasive material such as cerium oxide is supplied from the tip thereof to perform polishing. The other configurations and operations are the same as those in the first embodiment, and therefore will be omitted.

In the above embodiment, the material of the spherical body polishing tool 2 was not specified, but it goes without saying that a polishing tool containing abrasive grains such as cerium oxide may be used. The polishing liquid supplied in this case may be water. Further, in each of the above embodiments, the non-processed object is shown as an optical lens, but it is needless to say that it can be used not only for the optical lens but also for metal polishing.

[0021]

According to the present invention having the above-described structure and method, the rolling of the spherical body polishing tool has a true spherical shape due to the interaction of the rolling caused by the jet of fluid and the rolling caused by the rocking. As it advances, uneven wear does not occur. Further, since the contact pressure of the spherical body polishing tool with respect to the processing surface does not change, it is possible to obtain a highly accurate and high quality polishing surface.

[Brief description of drawings]

FIG. 1 is a front view showing the concept of a polishing method of the present invention and showing a part thereof in cross section.

FIG. 2 is a front view showing a main part of a polishing method according to a first embodiment of the present invention, a part of which is shown in cross section.

FIG. 3 is a front view showing a main part of a polishing method according to a second embodiment of the present invention, a part of which is shown in cross section.

FIG. 4 is a front view showing a main part of a polishing method according to a third embodiment of the present invention, a part of which is shown in cross section.

[Explanation of symbols]

 1, 9 and 10 Work piece 2 Spherical body polishing tool 3 Holder 4 Fluid supply hole 5 Spherical surface 6 Holder 7 Processing surface 8 Rotating shaft 11 Polishing liquid supply pipe

Claims (2)

[Claims] 1. An upper surface of a workpiece rotatably held,
A polishing method characterized in that a fluid is jetted and held from above a spherical surface of a holder for holding a spherical body polishing tool, and polishing is performed along a ridge line of a workpiece by swinging, rotating and vertically moving. 2. An upper surface of a workpiece rotatably held,
Fluid is jetted and held from above the spherical surface of the holder that holds the spherical body polishing tool, and is ground along the ridge line of the work piece by rocking, rotating, and vertically moving, and the polishing liquid is supplied from the side. A polishing method, which comprises polishing by polishing.