JP2976339B1 - Joint structure for vacuum piping - Google Patents

Abstract

An object of the present invention is to provide a joint structure of a vacuum pipe capable of improving work efficiency in connecting and disassembling a vacuum pipe and reducing the cost of a joint portion. SOLUTION: A flange 2a formed at a connection side end of one vacuum pipe 1 and a flange 4a formed at a connection side end of the other vacuum pipe 3 are opposed to each other.
In the joint structure of a vacuum pipe connecting the vacuum pipes 1 and 3 with the flanges abutting each other with the O-ring 5 sandwiched between the pipes a and 4a, the flange portion of one vacuum pipe 1 in the connection direction. The O-ring receiving portion 2c and the ring portion 2d are integrally protruded from the O-ring receiving portion 2c.
And positioning is performed by engaging the ring portion 2d with the annular groove 4c of the other vacuum pipe 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of a vacuum pipe used in a vacuum evacuation system in a semiconductor manufacturing apparatus, for example.

[0002]

2. Description of the Related Art Conventionally, vacuum equipment has been widely used due to the development of vacuum technology. For example, in semiconductor equipment, vacuum equipment has been used in a reaction gas exhaust system.

In this type of exhaust system, for example, when a vacuum pump or a pipe is replaced, disassembly or assembly is performed at a joint of the pipe.

FIG. 3 shows a joint structure of the vacuum pipe. In the figure, the joint structure comprises a pair of flanged tubes 30 and 31 and each of the flanged tubes 30 and 31.
It is composed of a center ring 32 interposed therebetween and an O-ring 33 attached to the outer peripheral surface of the center ring 32. After these are brought close to each other in the tube axis direction and combined together, the two flanged tubes 30 and 3
The first flange portions 30a and 31a are evenly tightened to connect the vacuum pipes 35 and 36 to each other.
The vacuum pipe 35 and the flanged pipe 30 are butt-welded.

[0005]

However, in the conventional joint structure, when the right and left flanged tubes 30 and 31 abut each other, the center ring 32 is formed with the annular groove of each flanged tube 30 and 31 (only 30b is shown). Therefore, there is a problem that the center ring 32 falls out of the annular groove 30b with a slight vibration because there is no means for holding the center ring 32.

The center ring 32 that has fallen into the gap between the pipes arranged in a complicated manner cannot be recovered.
Or, in many cases, recovery is difficult, and the efficiency of pipe connection work has been significantly reduced.

The center ring 32 is connected to the flange 30
In the conventional joint structure to be fitted to the flange 31 and
There is also a problem that the portion where each part engages must be precision machined, which increases the cost of the joint structure.

The present invention has been made in consideration of the above-described problems in the conventional joint structure of a vacuum pipe,
An object of the present invention is to provide a joint structure of a vacuum pipe capable of improving work efficiency in connecting and disassembling the vacuum pipe and reducing the cost of the joint.

According to the present invention, a flange formed at a connection end of one vacuum pipe is opposed to a flange formed at a connection end of the other vacuum pipe, and a seal is sandwiched between the two flanges. Butt the flanges together,
In the joint structure of a vacuum pipe connecting both vacuum pipes, a cylindrical body is extended from an inner peripheral side edge of a flange of one vacuum pipe, and a ring portion is formed at a tip side of the cylindrical body and positioned. A seal holding portion is formed, and an annular groove that can be engaged with the ring portion is formed on the inner peripheral side edge of the flange of the other vacuum pipe, and a seal disposed between both flanges is supported on the outer peripheral surface of the cylindrical body. And a joint structure for vacuum piping configured to perform connection positioning between vacuum piping by engagement of a ring portion and an annular groove.

In the present invention, it is preferable to form a stabilizing groove on the outer peripheral surface of the cylindrical body to prevent the seal from falling off.

In the present invention, the seal is preferably made of a rubber O-ring.

[0012]

According to the present invention, when the flange of one vacuum pipe and the flange of the other vacuum pipe are opposed to each other and approach each other in the pipe axis direction, the positioning formed on the flange of one vacuum pipe is performed. The seal holding part positions the other vacuum pipe, and the seal attached to the positioning seal holding part seals the connected vacuum pipe.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on a first embodiment shown in the drawings.

FIG. 1 shows an embodiment of a joint structure for a vacuum pipe according to the present invention. In FIG. 1, a joint structure includes a flanged pipe 2 butt-welded to a connection-side end of one vacuum pipe 1 and another vacuum pipe 3.
Pipe 4 butt-welded to the connection side end of
And a cylindrical portion (cylindrical body) integrally formed from the flange portion 2a of the flanged tube 2 and positioned with respect to the flanged tube 4 and to which an O-ring 5 as a seal is mounted
2c.

Hereinafter, the configuration of each unit will be described in detail.

Vacuum pipes 1, 3 and flanged pipes 2, 4
Are obtained by cutting members each made of SUS304. As shown in FIG. 2, the flanged pipe 2 has a straight pipe portion 2 b having the same inner diameter and the same outer diameter as the vacuum pipe 1, and a flange provided on an outer peripheral surface of a connection side end of the straight pipe portion 2 b. 2a. An O-ring receiving portion 2c having a U-shaped cross section (2c ') is formed on the distal end side of the flange portion 2a, and a thin wall for positioning is further provided on the distal end side of the O-ring receiving portion 2c. Ring portion 2d is formed.

The O-ring receiving portion 2c and the ring portion 2d can be regarded as a positioning seal holding portion, and the U-shaped cross section can be regarded as a stable groove.

An O-ring 5 having an inner diameter slightly smaller than the maximum diameter D of the O-ring receiving portion 2c is prepared, and fitted into the O-ring receiving portion 2c while being slightly extended. The O-ring 5 mounted on the O-ring receiving portion 2c fits into a U-shaped cross section so as not to easily fall off. In addition,
The O-ring 5 is formed by molding nitrile rubber, silicon rubber, or the like into a ring shape.

On the other hand, the flanged pipe 4 welded to the other vacuum pipe 3 has a straight pipe section 4b having the same inner diameter and the same outer diameter as the vacuum pipe 3, and a connection-side end of the straight pipe section 4b. And a flange portion 4a provided on the outer peripheral surface of
An annular groove 4c for accommodating the above-mentioned ring portion 2d is formed in the inner peripheral edge of the flange portion 4a.

The depth s of the annular groove 4 is formed larger than the length s 'of the ring portion 2d, and ss' is a tightening allowance.

Next, a method of connecting a vacuum pipe using the joint structure having the above configuration will be described with reference to FIG.

First, the O-ring 5 is mounted on the O-ring receiving portion 2c of the pipe 2 with the flange.

Next, the flange portion 2a of the flanged tube 2
And the flange portion 4a of the flanged tube 4 are opposed to each other. When the flanged tube 1 and the flanged tube 4 are abutted against each other, the ring portion 2d formed on the flanged tube 2 is replaced with the annular groove 4 formed on the flanged tube 4.
c (see FIG. 2), the positioning of both vacuum pipes 1 and 3 is performed.

Next, the free end of the split clamp ring 6 is rotated in the directions of arrows A and B, and attached so as to straddle the flange 2a and the flange 4a. When the wing nut 7 of the clamp ring 6 is fitted into the notch 8 and tightened, the inclined surfaces 6a 'and 6b' formed in the concave groove 6a of the crank ring 6 and the outer inclined surfaces of the flanges 2a and 4b come into contact with each other, and the wedge is formed. Flange 2a by effect
And 4b are pushed toward each other to compress the O-ring 5. Thereby, the flanged pipe 2 and the flanged pipe 4 are connected in an airtight state.

Conventionally, the center ring 32 (see FIG. 3) for attaching and positioning the O-ring has been formed as a separate component. However, in the present invention, since the positioning seal portions 2a and 2d corresponding to the center ring are formed integrally with the flange portion 2a of the one flanged pipe 2, the center ring does not fall off when the pipe is connected. Therefore, regardless of the installation environment and the installation state of the vacuum pipe, the pipe connection operation can be performed extremely easily.

In the above embodiment, the vacuum pipe of the present invention is constituted by a straight pipe, but is not limited to this, and may be constituted by an elbow, a tee, a reducer, a flexible tube or the like. Further, the material is not limited to a metal pipe, but may be a resin pipe molded using, for example, a fluororesin.

The means for tightening the flanges 2a, 4a is not limited to a clamp ring, but may be a crank chain.

[0029]

As is apparent from the above description,
According to the joint structure of the vacuum pipe of the present invention, the connection efficiency of the vacuum pipe, the work efficiency can be improved in disassembly,
In addition, there is an advantage that the cost of the joint can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a joint structure of a vacuum pipe according to the present invention.

FIG. 2 is a sectional view showing a configuration of a pipe with a flange in FIG. 1;

FIG. 3 is a view corresponding to FIG. 1 showing a joint structure of a conventional vacuum pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 One vacuum pipe 2 Flanged pipe 2a Flange part 2c O-ring receiving part 2d ring part 3 The other vacuum pipe 4 Flanged pipe 4c Annular groove 5 O-ring

Claims (3)

(57) [Claims] 1. A state in which a flange formed at a connection side end of one vacuum pipe faces a flange formed at a connection side end of the other vacuum pipe, and a seal is sandwiched between the two flanges. In the joint structure of a vacuum pipe connecting the two vacuum pipes with each other by abutting the flanges with each other ,
Extends and forms a ring at the tip of the cylinder
To form the positioning seal holding part, and for the other vacuum
Can be engaged with the ring portion on the inner peripheral edge of the flange of the pipe
An annular groove is formed, and the seal is disposed between the flanges.
Tool on the outer peripheral surface of the cylindrical body, and
Is determined by the engagement between the ring portion and the annular groove.
A joint structure for a vacuum pipe, wherein 2. The seal is detached on the outer peripheral surface of the cylindrical body.
2. The joint structure for a vacuum pipe according to claim 1, wherein a stabilizing groove for preventing the formation is formed . 3. The seal comprising a rubber O-ring.
3. The joint structure for a vacuum pipe according to claim 1 or 2 .