JPH0818241B2 - Polishing tool manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to polishing of optical elements such as lens mirrors or dies, and more particularly to a method of manufacturing a polishing tool for polishing a workpiece in a fluid or liquid.

(Prior art of the invention)

FIG. 6 shows a conventional method of polishing in liquid, in which a sphere made of resin 2 such as polyurethane is joined to the tip of a rotary shaft 1. By rotating this sphere in the polishing liquid and causing the polishing liquid 4 to circulate around it, the flow velocity required for the polishing liquid is obtained, and by bringing the sphere closer to the portion of the workpiece 6 to be polished, the movement of the polishing liquid to the gear part is achieved. Obtain pressure and perform polishing.

In this conventional example, since it is difficult to improve the processing accuracy of the polyurethane balls, the balls cannot be brought close to the work piece. Further, if the rotating polyurethane spheres are brought into contact with the workpiece, fine scratches will be formed and a good surface roughness cannot be obtained.

Furthermore, the rate of change of the polishing liquid flow rate in the vicinity of the polyurethane ball is 7th
As it falls sharply as shown in the figure (when the polishing liquid is a low viscosity aqueous solution), in order to give sufficient dynamic pressure to the processing point, the polyurethane sphere must be brought close to the processed product. In addition, since the processing accuracy of the ball is poor, it cannot be approached. The conventional example still has to have a very precise tool movement system because it must approach the work piece.

Since it is difficult to maintain proper processing conditions (1,
2) There were problems such as very poor processing efficiency.

[Problems of the Invention and Means for Achieving the Problems]

The present inventors arrange the workpiece and the polishing tool in the polishing liquid,
In a polishing method in which the polishing tool is rotated to cause the polishing solution to collide with the surface of the workpiece by the rotation of the polishing tool, the rate of change of the flow rate of the polishing solution with respect to the distance between the polishing tool and the workpiece is within a predetermined range. The polishing tool shown in FIG. 1 has been proposed as a polishing means for controlling.

The polishing tool shown in FIG. 1 has a rotary shaft 8 that rotates in the polishing liquid.
The porous sphere 10 is attached to the end of the porous sphere to form a rotary polishing tool in which a gel-like substance 12 is fixed around the sphere, and the gel-like substance 12 is formed into a hydrophilic polymer gel layer, thereby forming a hydrophilic polymer gel. Since the layers hang around, the wrapping speed of the polishing liquid is shifted from the central sphere by the gel layer. As a result, the central sphere can be processed sufficiently apart from the processed product, and the effect of increasing safety can be expected.

The present invention proposes a method for producing the above-mentioned polishing tool, and examines how the above-mentioned polishing tool fixes a gel layer to a sphere, and as a result, a porous core body is formed in a polishing layer molding die. Fixed to the porous core and a cavity for a polishing layer is provided between the porous core and the molding die, and a coating material for polishing is injected into the cavity to immerse the coating material in the pores of the porous core. At the same time, a method of filling and molding in the cavity is proposed.

[Explanation of Example]

2 to 5 show how to make the polishing tool shown in FIG.

First, a porous aluminum material 10a is attached to the tip of the rotary shaft 8.
Are fixed by fitting, screwing or the like (Fig. 2). Next, the aluminum material 10a is cut into a spherical shape (Fig. 3). The porous aluminum sphere 10a processed in this way is put into the molds 14A and 14B shown in FIG. 4 to form a gel layer.

The molds 14A and 14B are formed with a semi-circular convex part into which the rotary shaft 8 is fitted and a semi-spherical convex part into which the sphere and the gel layer are inserted, and one mold 14B
An injection port for injecting a gel material and injection paths 14b ₁ and 14b ₂ are provided therein.

When the rotary shaft is fitted into the semi-circular part of the molds 14A and 14B and both molds are closed, a cavity is provided to inject the gel material around the sphere. After the mold is closed, the gel material is injected from the injection port through the injection path into the cavity, and the gel material penetrates into the pores from the surface of the aluminum porous sphere as shown in FIG.

As a gel material, 1% of NN'methylenebisacrylamide as a cross-linking agent and a polymerization initiator (radical initiator) are added to a 5% aqueous solution of vinylpyrrolidone, and the mixture is immediately poured into a mold.
Then, it is heated to an appropriate temperature to start and end the polymerization. Then, the monomer enters the pores of the aluminum porous body and then the polymerization is started, so that the gel is firmly fixed to the surface of the sphere. The anchor effect and the accuracy of the sphere on the outer surface of the gel are relatively accurate because they are determined by the accuracy of the mold.

As the hydrophilic polymer gel, those having the degree of polymerization of the following monomers adjusted may be used.

For rigid (aluminum porous) spheres, high processing accuracy,
Therefore, the rotation accuracy is high.

Even if the gel contacts the work piece, the work piece is not scratched. Therefore, it is possible to use the part with a high flow velocity (close to a sphere), so the machining efficiency is high.

The polishing material in the polishing liquid is, for example, ultrafine silica powder (10
By using Å), the polishing liquid penetrates into the gel, and the boundary between the polishing liquid and the processing sphere can be further blurred.

As shown in FIG. 8, the polishing tool produced according to the present invention has a distance between the polishing tool and the workpiece that is farther than the conventional example, and the entanglement flow velocity does not decrease sharply. It has the effect of allowing the polishing liquid to act on the processed surface of the workpiece.

[Brief description of drawings]

FIG. 1 is a view showing a polishing action by a polishing tool according to the manufacturing method of the present invention. 2 to 6 show an embodiment of the present invention, FIG. 2 is an explanatory view of fixing porous aluminum to a rotating shaft, FIG. 3 is an explanatory view of a porous sphere, and FIG. 4 is a gel material. FIG. 5 is an explanatory view of molding into a spherical body, FIG. 5 is a view showing a fixed state of a gel material, FIGS. 6 and 7 are explanatory views of a conventional technique, and FIG. 8 is an explanatory view of an effect of the present invention. 8 …… Rotating axis 10 …… Porous aluminum sphere 12 …… Gel material 14A ・ 14B …… Mold

Claims (1)

[Claims] 1. A porous core is fixed in a polishing layer molding die,
A polishing layer cavity is provided between the porous core body and the molding die, a gel material is injected into the cavity, and the gel material is immersed in the porosity of the porous core body and inside the cavity. A method for manufacturing an abrasive tool, which comprises filling and manufacturing.