JPH0699329A - Air leak prevention method for vacuum chuck surface - Google Patents

Abstract

PURPOSE:To provide an air leak prevention method which prevent air leak from the chuck surface making no contact with a work, around the work in a vacuum chuck employing a chuck surface composed of porous material. CONSTITUTION:The method consists of a process in which a work is placed first over a chuck surface 3 composed of hard porous material fixedly set on a fixed surface 1 having vacuum holes 2, and the vacuum is drawn with silicone rubber 6 coated, which is located on the chuck surface 3 around the work 3, and of a process in which after coated silicone rubber 6 has been hardened with the work W removed from the chuck surface 3, the chuck surface 3 including the silicone rubber coated surface is flatly ground by a grinding wheel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing air leakage from a vacuum chuck surface for holding a workpiece by vacuum suction.

[0002]

2. Description of the Related Art When machining a workpiece with a machine tool, the workpiece may be held by a vacuum chuck. As shown in FIGS. 5 and 6, this vacuum chuck has a vacuum drawing hole 2 formed in the surface of the table 1, and a chuck face plate 3 made of a multi-pore member such as porous ceramic is brought into contact with the vacuum drawing hole 2. The structure is such that the outer periphery is fixed to the table 1 by the holder 4 via the seal material 5.

[0003]

In the above vacuum chuck, the workpiece W is placed on the chuck face plate 3 made of a multi-pore member, and the workpiece W is attached to the chuck face plate 3 by evacuating the workpiece W through the vacuum suction hole 2. It is vacuum-adsorbed and held.

However, if the area of the workpiece W is the same as the area of the chuck face plate 3, there is no problem, but generally the workpiece W is
The area of the chuck face plate 3 is formed larger than the area of. Therefore, when the workpiece W is placed on the chuck face plate 3, a width portion B where the workpiece W is not in contact with the chuck face plate 3 around the workpiece W is realized.

Due to the width portion B which is not in contact with the workpiece W, air leaks when the vacuum is drawn, and the workpiece W
However, there was a problem that the adsorption holding power of was decreased.

An object of the present invention is to provide a method for preventing air leakage from the width portion B which is not in contact with the workpiece W.

[0007]

According to the method of the present invention for achieving the above object, a workpiece is placed on a chuck face plate made of a rigid multi-pore member fixed to a fixed surface having a vacuum drawing hole. Then, the step of applying silicon rubber to the chuck face plate around the workpiece and drawing a vacuum, and the surface of the chuck face plate including the silicon rubber application face after removing the workpiece from the chuck face plate and curing the applied silicon rubber Is ground flat with a grindstone.

[0008]

With the above construction, the silicone rubber coating / penetrating portion is formed on the chuck face plate around the workpiece that is not in contact with the workpiece, and the silicone rubber coating / permeating portion blocks the multiple pores to block ventilation. To prevent air leakage. Further, by flattening the surface of the chuck face plate with a grindstone, the protrusion of the silicone rubber is eliminated, and the workpiece and the chuck face plate can be brought into close contact with each other even if a part of the workpiece protrudes into the coating / penetrating portion.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a table, on the surface of which a plurality of vacuum drawing holes 2 are opened. This vacuum draw hole 2
A circular chuck face plate 3 made of a multi-pore member such as a porous ceramic is brought into contact with the top, and the outer periphery thereof is fixed to the table 1 with a bolt 10 via a cylindrical holder 4 via a sealing material 5 to form a vacuum chuck. is doing.

A workpiece W is placed on the chuck face plate 3, and a silicon rubber 6 is applied to a width portion B of the chuck face plate 3 around the workpiece W, which is not in contact with the workpiece W, and a vacuum is drawn. As a result, a part of the silicone rubber 6 is sucked and permeated into the multi-pores.

Next, the workpiece W is removed from the chuck face plate 3. As shown in FIG. 2, on the surface of the chuck face plate 3 from which the workpiece W has been removed, the silicon rubber 6 rises up in the width portion B where the workpiece W coated with the silicone rubber 6 is not in contact, and the silicon is filled in the multi-pores. The rubber permeation part 6a is formed.

After the silicone rubber 6 is cured, as shown in FIG. 3, after the silicone rubber 6 is cured, the surface of the chuck face plate 3 including the raised silicone rubber 6 is flattened by a grindstone 7 rotated by a motor 8. Grind and finish.

The chuck face plate 3 which has been subjected to the flat grinding finish
As shown in FIG. 4, the swelling of the silicone rubber 6 in the width portion B not in contact with the workpiece W is removed, and the silicone rubber permeation portion 6a remains. Therefore, by placing the work W again in the above-mentioned fixed position, the chuck face plate 3 around the work W of the width B where the work W is not in contact is cut off by the silicone rubber permeation part 6a. It will be in the state of being.

As a result, since the workpiece W is vacuum-sucked, even if the workpiece W is evacuated, air leakage from the width portion B where the workpiece W is not in contact is prevented, and the silicone rubber 6 does not rise. The W can be firmly attached to the chuck face plate 3, the vacuum pressure can be increased, and the workpiece W can be sufficiently vacuum-held and held.

[0015]

As described above, according to the present invention, a workpiece is placed on a chuck face plate made of a hard multi-pore member fixed to a fixed face having a vacuum hole, and the chuck face plate around the workpiece is attached to the chuck face plate. Applying silicon rubber and vacuuming,
Air leakage in the width portion where the workpiece W is not in contact by a step of removing the workpiece from the chuck face plate and flattening the surface of the chuck face plate including the surface coated with the silicon rubber with a grind stone after the applied silicon rubber is cured. Prevent
A vacuum chuck can be obtained in which the workpiece and the chuck face plate can be firmly adhered to each other, and the workpiece can be prevented from coming off the vacuum chuck or being displaced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a silicone rubber applying step of the method of the present invention.

FIG. 2 is a cross-sectional view with the workpiece removed.

FIG. 3 is a sectional view showing a state where the surface of the chuck face plate is flat-ground.

FIG. 4 is a cross-sectional view of a chuck face plate that has been finished by flat grinding.

FIG. 5 is a plan view of a conventional vacuum chuck.

6 is a sectional view of FIG.

[Explanation of symbols]

 1 Table 2 Vacuum suction hole 3 Chuck face plate 4 Holder 6 Silicon rubber 6a Silicon rubber penetration part

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroshi Ishigure, 1-1 Asahi-cho, Kariya city, Aichi Toyota Koki Co., Ltd. Incorporated (72) Inventor Sumitaka Noda 1 at 2-1-1, Jyoryo, Nishibiwajima-cho, Nishikasugai-gun, Aichi Prefecture Within Fujimi Incorporated

Claims (1)

[Claims] 1. A workpiece is placed on a chuck face plate composed of a hard multi-pore member fixed to a fixed surface having a vacuum suction hole, and silicon rubber is applied to the chuck face plate around the workpiece to perform vacuuming. A method for preventing air leakage of a vacuum chuck surface, which comprises the steps of: removing a workpiece from a chuck face plate, and flattening the surface of the chuck face plate including the silicon rubber coated face with a grind stone after the applied silicon rubber is cured. .