JPH0780762A - Grinding machining method of cylindrical ceramic body - Google Patents

Abstract

PURPOSE:To obtain a cylindrical ceramic body which has no gall and no breakage caused by the effect of the abrasive grains on the surface of a grinding wheel and has good out-of-roundness. CONSTITUTION:In a grinding machining method of a cylindrical ceramics body by a centerless grinder, the cylindrical ceramics body 5 is rotated before the cylindrical ceramic body 5 and a grinding wheel 1 make contact with each other, or the process to reduce the moving speed of the cylindrical ceramics body 5 and/or the process to increase the rotating speed of the cylindrical ceramic body 5, up-to the final size position after the cylindrical ceramic body 5 and the grinding wheel 1 make contact with each other, are applied.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for grinding a cylindrical ceramic body using a centerless grinder,
In particular, the present invention relates to a method of grinding a cylindrical ceramic body suitable for processing a thin-walled cylindrical ceramic body.

[0002]

2. Description of the Related Art Conventionally, a work such as a cylindrical or cylindrical ceramic body is rotatably supported by an adjusting roller and a support base without using a means such as a chuck, and is brought into contact with a grinding wheel. The centerless grinder that grinds the outer periphery of the work is, for example, the actual flat blade 4-11.
As disclosed in Japanese Patent No. 5562, an example of which is disclosed, various types are known.

FIG. 6 is a view showing an example of the main part of a conventional centerless grinder, 21 is an adjusting roller, 2
2 is a support base, 23 is a grinding wheel, and 24 is a work. In the example shown in FIG. 5, the work 24 is rotatably supported by rotating the adjusting roller 21 and the grinding wheel 23 on the support base 22 in the arrow direction, and in this state, the outer circumference of the work 24 is ground. You can

[0004]

With the above-described conventionally known centerless grinder, the outer periphery of a generally cylindrical or cylindrical work can be ground with high precision. However, since the structure of the grinding wheel is composed of abrasive grains with an uneven surface, the work to be ground and the grinding wheel are in contact with each other, as is the case when grinding a heavy work such as a normal metal. When the work is rotated from, for example, when the work is a soft cylindrical ceramic molded body or a degreased body, the effect of the abrasive grains on the surface of the grinding wheel at the start of rotation after contact between the grinding stone and the cylindrical ceramic molded body, etc. However, there is a problem that galling and breakage of the cylindrical ceramic molded body and the like, and there is a problem that a cylindrical ceramic body having good roundness cannot be obtained without such galling and breakage.

The object of the present invention is to solve the above problems,
An object of the present invention is to provide a grinding method for a cylindrical ceramic body capable of obtaining a cylindrical ceramic body having good roundness without galling or damage due to the influence of abrasive grains on the surface of the grinding stone.

[0006]

A first aspect of the method of grinding a cylindrical ceramic body according to the present invention is a method of grinding a cylindrical ceramic body by a centerless grinder.
It is characterized in that the cylindrical ceramic body is brought into contact with a grinding wheel while the cylindrical ceramic body is being rotated.

The second invention of the method of grinding a cylindrical ceramic body of the present invention is the method of grinding a cylindrical ceramic body by a centerless grinder, wherein the cylindrical ceramic body received by the adjusting roller and the support base is moved in the direction of the grinding wheel. In the case where the cylindrical ceramic body is moved to the final dimension position and ground, the moving speed is reduced until the cylindrical ceramic body reaches the final dimension position after coming into contact with the grinding wheel.

Further, a third invention of the method for grinding a cylindrical ceramic body of the present invention is the method for grinding a cylindrical ceramic body by a centerless grinder, wherein the cylindrical ceramic body received by the adjusting roller and the support base is moved in the direction of the grinding wheel. When moving to the final dimension position of and performing grinding processing, the rotation speed of the cylindrical ceramic body increases continuously until it reaches the final dimension position after the cylindrical ceramic body contacts the grinding wheel. Is.

Furthermore, in the method of grinding a cylindrical ceramic body by a centerless grinder, when the cylindrical ceramic body received by the adjusting roller and the support is moved to the final dimension position in the grinding wheel direction for grinding.
It is characterized in that the moving speed of the cylindrical ceramic body is reduced and the rotational speed of the cylindrical ceramic body is continuously increased by the time the cylindrical ceramic body contacts the grinding wheel and reaches the final dimension position. .

[0010]

In the above-mentioned structure, the first to fourth inventions of the present invention are all related to the grinding process of the cylindrical ceramic body by the centerless grinder, of which the first invention is such that the cylindrical ceramic body and the grinding wheel contact each other. The steps up to and the second to fourth inventions respectively show the steps after the cylindrical ceramic body and the grinding wheel contact each other. In the present invention, the "cylindrical ceramic body" to be ground is a cylindrical body with a bottom, a cylinder with both ends open, and a soft raw material such as a ceramic molded body before firing, a ceramic degreased body, or the like. The present invention is effective for a cylindrical ceramic body, which is particularly thin and difficult to grind.

In the first aspect of the present invention, since the cylindrical ceramic body is rotated before the cylindrical ceramic body and the grinding grindstone contact each other, the surface of the grinding grindstone at the time when the cylindrical ceramic body and the grinding grindstone contact each other. It becomes possible to reduce the influence of the abrasive grains as compared with the conventional case in which rotation is started after contact, and it is possible to eliminate galling and breakage of the cylindrical ceramic body.

In the second to fourth inventions of the present invention,
After the contact between the cylindrical ceramic body and the grinding wheel, the step of reducing the moving speed of the cylindrical ceramic body to the final dimension position and / or the step of increasing the rotational speed of the cylindrical ceramic body are performed, so that the grinding process proceeds. Accordingly, even if the cylindrical ceramic body is not thin, damage and the like can be prevented, and at the same time, the productivity can be kept high.

[0013]

FIG. 1 is a view showing an example of a centerless grinder used in the method for grinding a cylindrical ceramic body according to the present invention. In the example shown in FIG. 1, 1 is a grinding wheel, 2 is an adjusting roller, 3 is a support base, 4 is an adjusting roller driving device for rotating the adjusting roller 2, 5 is a cylindrical ceramic body as a workpiece to be ground, Reference numeral 6 denotes a slide base that fixes the support base 3 and the adjusting roller drive device 4 and is movable in the arrow direction.

In the centerless grinder having the above-mentioned structure, the cylindrical ceramic body 2 is mounted on the support base 3 and the adjusting roller 2.
And the grinding roller 1 is rotated by the adjusting roller driving device 4 so that the cylindrical ceramic body 5 and the grinding stone 1 that is rotated by the driving means (not shown) after the cylindrical ceramic body 5 and the grinding stone 1 come into contact with each other. Each can be rotated in the direction of the arrow, and by moving the slide table 6 in the direction of the grinding wheel 1 in this state,
The outer surface of the cylindrical ceramic body 5 can be ground.

FIG. 2 is a diagram for explaining an example of a grinding method for a cylindrical ceramic body according to the present invention. In the example shown in FIG. 2, the same members as those in the example shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. The example shown in FIG. 2 corresponds to the first invention of the present invention. First, a cylindrical ceramic body 5 such as a ceramic molded body or a ceramic degreased body is supported on a support base 3 and an adjusting roller 2, and the adjusting roller 2 is rotated. Then, the cylindrical ceramic body 5 is rotated. In this state, the slide table 6 is moved toward the grinding wheel 1 and brought into contact with the rotating grinding wheel 1 by a driving device (not shown). This eliminates damage and the like when the cylindrical ceramic body 5 comes into contact with the grinding stone 1.

When the cylindrical ceramic body 5 shown in FIG. 2 is rotated before contacting the grinding stone 1, the cylindrical ceramic body 5 is rotated by some holding means 7 as shown in FIG. It is preferable that pressure is applied to the cylindrical ceramic body 5 from the upper portion, and the partial pressure of the pressure acts on the adjusting roller 2 and the support base 3.
Furthermore, it is preferable that the pressing means 7 has elasticity that follows changes in the shape of the cylindrical ceramic body during rotation. As such a pressing means 7, a pressing roller, compressed air,
Brushes or elastics can be used. When the pressing means 7 as shown in FIG. 3 is used, the cylindrical ceramic body 5 can be rotated more smoothly.

In the first aspect of the present invention, the rotational speed of the cylindrical ceramic body 5 before contacting the grinding wheel 1 is not particularly limited, but the rotational speed (N) of the cylindrical ceramic body 5 is 10≤. It is preferable that N ≦ 150 (rpm), preferably 30 ≦ N ≦ 100 (rpm), because the cylindrical ceramic body 5 can be smoothly rotated, and further, damage or the like at the time of contact with the grinding wheel 1 can be prevented.

FIG. 4 is a view for explaining another example of the method for grinding a cylindrical ceramic body according to the present invention. The example shown in FIG. 4 shows an example of the second invention of the present invention, and the example of the processed state is the same as the example shown in FIG. The second invention of the present invention is different from the above-mentioned first invention and relates to a grinding method after the cylindrical ceramic body 5 and the grinding wheel 1 are in contact with each other. That is, as shown in FIG. 4 which shows the relationship between the moving speed of the cylindrical ceramic body 5 and the grinding allowance, the moving speed of the cylindrical ceramic body 5 after reaching the final grinding position (grinding allowance ΔG1) after contacting the grinding wheel 1. Is reduced from v1 to v2.

The method of reducing the grinding speed may be stepwise as indicated by a in FIG. 4 or continuous as indicated by b, and the cylindrical ceramic body 5 may be used.
It is preferable that v1 is about 100 μm / s and v2 is about 10 μm / s. Further, the cylindrical ceramic body 5 may be moved by fixing the position of the grinding wheel 1 and moving the slide base 6, or by fixing the slide table 6 and moving the grinding wheel 1. Nor.

As shown in FIG. 4, when the grinding speed of the cylindrical ceramic body 5 is decreased, the grinding speed is decreased corresponding to the gradually thinning of the thin-walled cylindrical ceramic body. Compared with the case where the grinding speed is slowed from the beginning to prevent breakage of the cylindrical ceramic body 5, the productivity can be improved and the breakage of the cylindrical ceramic body 5 can be prevented.

FIG. 5 is a view for explaining still another example of the method for grinding a cylindrical ceramic body according to the present invention. Figure 5
The example shown in 1 shows an example of the third invention of the present invention, and the example of the processed state is the same as the example shown in FIG.
The third invention of the present invention relates to a grinding method after the cylindrical ceramic body 5 and the grinding wheel 1 are in contact with each other, similarly to the above-mentioned second invention. That is, as shown in FIG. 5 showing the relationship between the rotational speed of the cylindrical ceramic body 5 and the grinding allowance, the rotational speed until the cylindrical ceramic body 5 reaches the final dimension position (grinding allowance ΔG1) after coming into contact with the grinding wheel 1 is shown. It is continuously increased from N0 to N1.

Regarding the rotational speed of the cylindrical ceramic body 5, N0 is preferably 66 rpm and N1 is preferably 180 rpm. As shown in FIG. 5, when the rotational speed of the cylindrical ceramic body 5 is increased under the condition that the moving speed is constant, the grinding amount is reduced corresponding to the gradually thinning of the thin cylindrical ceramic body 5. Therefore, it is possible to prevent the cylindrical ceramic body 5 from being damaged.

Furthermore, a fourth invention of the present invention relates to a grinding method after the cylindrical ceramic body 5 and the grinding wheel 1 are in contact with each other, and is a combination of the above-mentioned second invention and third invention. , Which have a synergistic effect of each effect. In the above-described embodiment, the cylindrical ceramic body 5 and the grinding wheel 1 were separately described before and after contacting each other, but of course before and after contacting each other, that is, the first invention and the second invention to the fourth invention of the present invention. Combined with the invention,
It goes without saying that a better cylindrical ceramic body can be ground.

Actually, a grinding wheel 1 having a diameter of 500 mm
And a diameter made of natural rubber with a Shore A hardness of 70 °:
330mm adjusting roller 2 and outer diameter: 50mm, wall thickness: 2mm, length: 450mm cylindrical dry type CIP
After that, a cylindrical ceramic body 5 made of alumina is prepared,
1st invention-4th invention was implemented.

First, regarding the first invention, when the adjusting roller 2 is rotated at 10 rpm and the cylindrical ceramic body 5 is rotated at 66 rpm, the cylindrical ceramic body 5 is brought into contact with the grinding wheel 1 rotating at a predetermined number of revolutions. The body 5 could be ground without damage. Next, two second inventions in which the moving speed of the cylindrical ceramic body 5 is changed according to the curves of a and b of FIG. 4 from the state where the cylindrical ceramic body 5 and the grinding wheel 1 are in contact to the final dimension position. When the third invention in which the rotation speed of the cylindrical ceramic body is changed according to the curve in FIG. 5 and the two fourth inventions in which both the two curves in FIG. 4 and the curve in FIG. 5 are implemented are carried out, In each case, the cylindrical ceramic body 5 could be ground without damage.

The present invention is not limited to the above-mentioned embodiments, but various modifications and changes can be made. For example, the embodiment described above is an example of the present invention,
The invention can be achieved by reducing the moving speed from the time of contact other than the curve of the moving speed shown in FIG. 4 and increasing the rotational speed from the time of contact other than the curve of the rotating speed shown in FIG. 5, respectively. Needless to say.

[0027]

As is apparent from the above description, in the first aspect of the present invention, by rotating the cylindrical ceramic body before the cylindrical ceramic body and the grinding wheel contact each other,
In the second to fourth aspects of the present invention, the step of decreasing the moving speed of the cylindrical ceramic body to the final dimension position after the cylindrical ceramic body and the grinding wheel contact each other and / or the rotating speed of the cylindrical ceramic body is increased. By taking the step, the thin cylindrical ceramic body can be ground with high productivity without damage.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a centerless grinder used in a method for grinding a cylindrical ceramic body according to the present invention.

FIG. 2 is a diagram for explaining an example of a grinding method for a cylindrical ceramic body according to the present invention.

FIG. 3 is a diagram for explaining another example of the method for grinding a cylindrical ceramic body according to the present invention.

FIG. 4 is a diagram showing a relationship between a moving speed of a cylindrical ceramic body and a grinding allowance in a second aspect of the invention.

FIG. 5 is a diagram showing the relationship between the rotational speed of the cylindrical ceramic body and the grinding allowance in the third aspect of the present invention.

FIG. 6 is a diagram showing an example of a main part of a conventional centerless grinder.

[Explanation of symbols]

1 grinding wheel, 2 adjustment roller, 3 support base, 4 adjustment roller drive device, 5 cylindrical ceramic body, 6 slide base, 7 holding means

Claims (9)

[Claims] 1. A method of grinding a cylindrical ceramic body by a centerless grinder, wherein the cylindrical ceramic body is brought into contact with a grinding wheel while the cylindrical ceramic body is being rotated. 2. The cylindrical ceramic body received by the adjusting roller and the supporting base is rotated while a predetermined pressure is applied by the pressing means so that the component of the pressure acts on the adjusting roller and the supporting base. Grinding method of cylindrical ceramic body. 3. The method of grinding a cylindrical ceramic body according to claim 2, wherein the pressing means has elasticity that follows changes in the shape of the cylindrical ceramic body during rotation. 4. The method for grinding a cylindrical ceramic body according to claim 2, wherein the pressing means is a pressing roller, compressed air, a brush or an elastic body. 5. A method for grinding a cylindrical ceramic body using a centerless grinder, wherein when the cylindrical ceramic body received by an adjusting roller and a support is moved to a final dimension position in the grinding wheel direction and ground, the cylindrical ceramic body is ground. A method of grinding a cylindrical ceramic body, comprising reducing a moving speed of the blade until it reaches a final dimensional position after coming into contact with a grinding wheel. 6. The method of grinding a cylindrical ceramic body according to claim 5, wherein the moving speed of the cylindrical ceramic body is reduced stepwise or continuously. 7. A method of grinding a cylindrical ceramic body by a centerless grinder, wherein when the cylindrical ceramic body received by an adjusting roller and a support is moved to a final dimension position in the grinding wheel direction and ground, the cylindrical ceramic body is ground. The method for grinding a cylindrical ceramic body, wherein the rotational speed of the cylindrical ceramic body is continuously increased until the final dimension position is reached after the contact with the grinding wheel. 8. A method of grinding a cylindrical ceramic body by a centerless grinder, wherein when the cylindrical ceramic body received by an adjusting roller and a support is moved to a final dimension position in the grinding wheel direction for grinding, the cylindrical ceramic body is ground. Grinding of a cylindrical ceramic body characterized by decreasing the moving speed of the cylindrical ceramic body and continuously increasing the rotating speed of the cylindrical ceramic body by the time when it reaches the final dimension position after contacting the grinding wheel. Method. 9. The method of grinding a cylindrical ceramic body according to claim 8, wherein the moving speed of the cylindrical ceramic body is reduced stepwise or continuously.