JP2624924B2 - Fluid coupling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid coupling used in a gas supply device used in an industrial production device such as a semiconductor production device, and more particularly to a fluid coupling used in a device supplying a toxic gas. The present invention relates to a gas joint having a high degree of airtightness.

[0002]

2. Description of the Related Art Conventionally, in a semiconductor manufacturing process, thermal diffusion has been performed on a silicon base using a supertoxic gas such as silane, arsine, phosphine, diborane or the like as an impurity source. Also, pyrophoric gases are used.
For example, the lethal dose of arsine is 0.5 ppm, and a small amount of leakage leads to personal injury. Therefore, pipes for these gases are connected by welding in order to prevent leakage.

On the other hand, in a method of connecting pipes without using welding, a joint shown in FIG. 5 is used for piping of non-toxic gas such as compressed air. Pipes 5 and 7 are inserted into both ends of the through hole of the body 6. A male screw 6a is formed on the outer periphery of the body 6, and a female screw 1a formed inside the cap nut 1 is fastened to the male screw 6a.

A large chamfer is formed at the entrance of the through hole of the body 6, and a wedge-shaped sleeve 12 is fitted into the chamfer. A through hole is formed at the center of the sleeve 12 and is fitted to the pipes 5 and 7. A seat 11 for stopping rotation is in contact with the bottom surface of the sleeve 12. The opposite end surface of the seat 11 is in contact with the inner end surface of the cap nut 1. A through hole is formed at the center of the sleeve 12 and is fitted to the pipes 5 and 7.

In the joint having such a configuration, when the cap nut 1 is screwed into the body 6 with a predetermined torque,
The sleeve 12 is pressed inward by the body 6 and comes into close contact with the outer periphery of the pipes 5, 7 to deform the pipes 5, 7. Thereby, the adhesiveness between the outer peripheral surfaces of the pipes 5 and 7 and the inner surface of the sleeve 12 and the adhesiveness between the outer peripheral surface of the sleeve 12 and the inner surface of the chamfered portion of the body 6 are ensured, and the airtightness of the joint is ensured.

However, the joint shown in FIG. 5 has the following problems. (1) The airtightness is not sufficient, and it is dangerous to use for toxic gas piping. (2) When removing, attach pipes 5 and 7 to body 6
Since it cannot be removed unless it is removed from the pipe, it is necessary to provide an extra escape portion in the pipe, which is wasteful. (3) Once fastened, the pipe will be crushed and deformed, resulting in poor airtightness when removed and reassembled.

[0007] In spite of the above-mentioned problems, it is absolutely necessary to use a joint when connecting to a valve.
Are used with great care in the manufacturing process of semiconductors that handle toxic gases and the like. However, in recent years, a joint disclosed in Japanese Patent Publication No. 2-46830 or the like, which can maintain high airtightness, has been used as means for solving the above problem. However, this joint has a special shape for the sleeve used,
The sleeve and the pipe for piping were connected by welding.

[0008]

However, when a toxic gas is used as an impurity source for thermal diffusion, the following problems arise when the pipes are connected by welding. (1) Floating elements are generated by welding and mixed into the wafer as metal impurities, which impairs device reliability.

(2) Many gases as impurity sources have corrosive properties, and SUS materials are usually used for pipes. However, the material of the welded portion is changed by welding, and it is easily corroded. Therefore, particles are generated, and the defective product rate due to the pattern defect increases.

(3) Skilled welding is required for welding SUS pipes.
It was not easy to secure skilled welding workers.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a fluid coupling used in a semiconductor manufacturing process or the like in which the generation of metal impurities and particles is small and the mounting is easy.

[0012]

In order to achieve this object, a fluid coupling according to the present invention comprises a cap nut having a female thread formed inside, a pipe having a mirror-finished surface on an end face, and a cap nut. A co-rotation preventing means abutting the inner end face to prevent co-rotation between the cap nut and the pipe, and a ferrule attached to the outer periphery of the pipe and abutting against the co-rotation preventing means to transmit the thrust force of the cap nut in the pipe longitudinal direction to the pipe And a gasket fitted to the end of the pipe and abutting the entire circumference of the pipe end face, and a body having a mirror-finished surface on the end face and a male screw formed on the outer circumference, and the end face of the body is a gasket pipe. Abuts on the surface opposite to the surface on which the abutment is made, and the male screw of the body and the female screw of the cap nut are fastened with a predetermined torque.

In order to achieve this object, a fluid coupling according to the present invention comprises: a cap nut having an internal thread formed therein;
A first pipe having a mirror-finished surface on its end face, co-rotation preventing means for contacting the inner end face of the cap nut and preventing co-rotation of the cap nut and the pipe, and a first co-rotation attached to the outer periphery of the first pipe A first ferrule that contacts the prevention means and transmits the propulsion force of the cap nut in the pipe longitudinal direction to the first pipe, a body having an external thread formed on the outer periphery, and a second pipe having a mirror-finished surface on the end face, Co-rotation prevention means for contacting the end face of the body to prevent co-rotation of the cap nut and the second pipe;
A second ferrule which is attached to the outer periphery of the second pipe and abuts against the second co-rotation preventing means and transmits the thrust of the cap nut in the pipe longitudinal direction to the second pipe, and is fitted to an end of the first pipe or the second pipe. A gasket is provided which is brought into contact with the entire circumference of the first pipe end face and the second pipe end face from both sides, and the male screw of the body and the female screw of the cap nut are fastened with a predetermined torque.

[0014]

The assembling method of the present invention having the above configuration will be described. With the ferrule and the gasket mounted, the pipe is inserted into the cap nut on which the thrust bearing is mounted, and the cap nut is screwed into the body. With the body fixed so that it does not rotate, the cap nut is screwed in until the specified torque is reached. When the cap nut is screwed into the body, the thrust is transmitted to the pipe by the ferrule.

At this time, since the pipe is positioned by the ferrule with respect to the cap nut, the end face of the pipe and the end face of the body are accurately aligned. Here, the end surface of the pipe and the end surface of the body are mirror-finished by roller burnishing or the like, so that the adhesion between each of them and the gasket is improved, and the airtightness of the joint is improved.

Although the Vickers hardness of the SUS material is about 180, the Vickers hardness can be made about 300 by mirror finishing by roller burnishing or the like. Thus, even if the pipe end face and the body end face are pressed against the gasket by the strong pressing force, the pipe end face and the body end face are not deformed, and thus can be used repeatedly. The gasket is pressed from both sides by the end face of the pipe and the end face of the body. The gasket is made of a soft metal, and is pressed against the end face of the pipe and the end face of the body having high hardness, so that each can be in close contact with each other.

When the cap nut is screwed into the body, the thrust bearing is mounted as co-rotation preventing means, so that the pipe is prevented from co-rotating with the cap nut.
If the cap nut is removed, the connection can be easily released by simply sliding the pipe sideways.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fluid coupling according to one embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a sectional view of an embodiment in which pipes are connected to both ends of a body. FIG. 3 is an exploded perspective view showing the configuration of the main parts of the joint.
A thrust bearing 3, which is a co-rotation preventing means, is fitted in contact with the inner end surface of the cap nut 1 having the female screw 1a formed inside.

A pipe 5 is mounted inside the thrust bearing 3. As shown in FIG. 4, the end face of the pipe 5 is chamfered at the tip, and the tip end face 5b is mirror-finished by roll burnishing. In addition, a groove 5 a is cut in the peripheral surface of the pipe 5. A sleeve 2a having a cut groove in the longitudinal direction and having a wedge-shaped cross section is fitted into the groove 5a. The sleeve 2b having the same inclination on the inner surface as the wedge-shaped inclination of the sleeve 2a is fitted to the sleeve 2a. The sleeve 2a and the sleeve 2b are fitted together to form a ferrule.

A gasket 4 is attached with an inner surface fitted to the end of the pipe 5 and an inner end surface in contact with the entire periphery of the pipe end surface 5b. Further, the end face 6b is subjected to roll burnishing, and the male screw 6a of the body 6 having the male screw 6a formed on the outer periphery is fastened to the female screw 1a of the cap nut 1. The end surface 6b of the body 6 is in contact with the surface of the gasket 4 opposite to the surface of the gasket 4 in contact with the pipe end surface 5b. The mounting configuration of the pipe 7 on the opposite side is the same as that of the pipe 5, and the description is omitted.

Next, the operation of the fluid coupling having the above configuration will be described. The pipes 5 and 7 to be connected are cut to a length that is actually used, and chamfered on an end face, followed by roller burnishing. By mirror finishing by roller burnishing, the adhesion between the pipe end face 5b and the gasket 4 is improved, and the airtightness of the joint is enhanced.

The Vickers hardness of the SUS material is about 180, but by performing roller burnishing,
Vickers hardness can be about 300. Thus, even if the pipe end face 5b is pressed against the gasket with a strong pressing force, the pipe end face 5b is not deformed, and can be used repeatedly.

A groove 5a shown in FIG.
Is formed by processing with a lathe or the like. In the groove 5a of the pipe 5,
The sleeve 2a is mounted so as to widen the cut groove. The sleeve 2b is fitted so as to fit with the inclination of the outer surface of the sleeve 2a.
Attach. The gasket 4 is fitted to the end of the pipe 5. With the ferrule 2 constituted by a combination of the sleeve 2a and the sleeve 2b and the gasket 4 mounted, the pipes 5, 7 are inserted into the cap nut 1 on which the thrust bearing 3 is mounted, and the cap nut 1 is removed. Screw it into the body 6.

With the body 6 fixed so as not to rotate, the cap nut 1 is screwed in until it reaches a predetermined torque. Propulsion force for screwing the cap nut 1 into the body 6 is transmitted to the pipes 5 and 7 via the ferrule 2. Since the sleeve 2a constituting the ferrule fits into the groove 5b formed on the outer periphery of the pipe, the ferrule 2
Can transmit strong propulsion to the pipe.

At this time, since the pipe 5 is positioned by the ferrule 2 with respect to the cap nut 1, the end face 5b of the pipe and the end face 6b of the body 6 are accurately aligned. Here, the body end face 6b is mirror-finished by roller burnishing, so that the adhesion between the body end face 6b and the gasket 4 is improved, and the airtightness of the joint is enhanced.

The Vickers hardness of the SUS material is about 180, but by performing roller burnishing,
Vickers hardness can be about 300. Thus, even if the body end face 6b is pressed against the gasket with a strong pressing force, the body end face 6b is not deformed, and can be used repeatedly. The gasket 4 is pressed from both sides by the end face 5b of the pipe and the end face 6b of the body 6. The gasket 4 is made of nickel in this embodiment,
It is pressed against the end face 5b of the pipe having high hardness and the end face 6b of the body 6 so that they can be in close contact with each other.

Since the thrust bearing 3 is mounted when the cap nut 1 is screwed into the body 6, the pipe is prevented from rotating together with the cap nut 1, so that the pipe end face 5b and the gasket 4 Rubbing does not occur between the gaskets 4 or between the gasket 4 and the body end surface 6b, and no particles are generated.

According to the fluid coupling having the above-described structure, the ferrule 2 can be easily attached to the ordinary pipe only by performing a simple additional process, so that the pipes are highly airtight without welding. Can be connected in state. In addition, if the cap nut 1 is removed, the connection can be easily released simply by sliding the pipe 5 sideways, so that there is no need to provide an extra relief in the pipe, and the cost can be reduced.

Since the pipe end face 5b and the body end face 6b are finished by roller burnishing, the gasket 4
And the fluid coupling can be configured with high airtightness. Further, since the hardness of the pipe end face 5b and the body end face 6b is high, the gasket 4 is considered to be deformed, so that the gasket 4 can be used repeatedly only by replacing it.

Next, a second embodiment will be described with reference to FIG. A second embodiment is a fluid coupling performed using a single cap nut to connect a set of pipes. A first thrust bearing 3a, which is first co-rotation preventing means, is fitted in contact with the inner end surface of the cap nut 1 having the female screw 1a formed inside.

A pipe 5, which is a first pipe, is mounted inside the thrust bearing 3a. As shown in FIG. 4, the end face of the pipe 5 is chamfered at the tip, and the tip end face 5b is mirror-finished by roll burnishing. In addition, a groove 5 a is cut in the peripheral surface of the pipe 5. A sleeve 2a having a cut groove in the longitudinal direction and having a wedge-shaped cross section is fitted into the groove 5a. The sleeve 2b having the same inclination on the inner surface as the wedge-shaped inclination of the sleeve 2a is fitted to the sleeve 2a. The ferrule 2 is formed by fitting the sleeve 2a and the sleeve 2b.

A gasket 4 is mounted with an inner surface fitted on the end of the pipe 5 and an inner end surface in contact with the entire periphery of the pipe end surface 5b. Inside the cap nut 1, a pipe 7, which is a second pipe having a roll burnishing finished surface formed on an end face, is attached. The end face of the pipe 7 is mirror-finished by roll burnishing similarly to the pipe end face 5b.

A groove 7a is formed in the peripheral surface of the pipe 7. A sleeve 2a having a cut groove in the longitudinal direction and having a wedge-shaped cross section is fitted into the groove 7a. The sleeve 2b having the same inclination on the inner surface as the wedge-shaped inclination of the sleeve 2a is fitted to the sleeve 2a. The ferrule 2 is formed by fitting the sleeve 2a and the sleeve 2b. A second thrust bearing 3b, which is a second co-rotation preventing means, is attached to the ferrule 2 in contact therewith. The end surface of the body 8 having the external thread 8a formed on the outer periphery is in contact with the thrust bearing 3b.

Next, the operation of the second embodiment will be described. With the body 8 fixed so as not to rotate, the cap nut 1 is screwed in until the predetermined torque is reached. Propulsion force for screwing the cap nut 1 into the body 6 is transmitted to the pipes 5 and 7 via the ferrule 2. Since the sleeve 2a constituting the ferrule fits into the groove 5b formed on the outer periphery of the pipe, the ferrule 2 can transmit a strong propulsive force to the pipe.

At this time, since the pipes 5 and 7 are positioned by the ferrule 2 with respect to the cap nut 1, the end face 5b of the first pipe and the end face 7b of the second pipe are accurately aligned. Further, a pair of pipes 5 and 7 are abutted and pressed with the gasket 4 therebetween. Pipe end face 5
Both b and 7b are subjected to roller burnishing, and the gasket 4 made of nickel is deformed so that the pipe end faces 5b and 7b are deformed.
b, the airtightness is improved.

According to the above embodiment, since the gas tightness is high, there is no danger even when a highly toxic gas is used in the semiconductor manufacturing process. Also, if you remove the cap nut, you can easily remove the pipe simply by sliding it sideways,
Easy maintenance. In this embodiment, the ferrule is attached to the pipe by forming a groove in the outer periphery of the pipe. However, another method may be used as long as the driving force of the cap nut can be transmitted to the pipe. For example, a ferrule may be attached by making a hole in the pipe.

[0037]

As is clear from the above description, according to the fluid coupling of the present invention, the ferrule 2 can be easily attached to the ordinary pipe simply by performing a simple additional process. Since the pipes can be connected to each other in a highly air-tight state without performing the process, floating elements are not generated by welding and mixed into the wafer as metal impurities, so that the reliability of the device is not impaired.

Further, since the material is not changed by welding,
No particles are generated, and the defective rate due to pattern defects is reduced. In addition, the assembly is easy, and a skilled welding worker is not required in the construction of the semiconductor manufacturing process, and the construction can be performed efficiently.

Further, if the cap nut is removed, the connection can be easily released by simply sliding the pipe sideways, so that there is no need to provide an extra relief in the pipe, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a fluid coupling according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a fluid coupling according to a second embodiment of the present invention.

FIG. 3 is an exploded perspective view showing a configuration of a main part of the first embodiment.

FIG. 4 is a sectional view of a pipe end.

FIG. 5 is a cross-sectional view showing a configuration of a conventional fluid coupling.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap nut 2 Ferrule 3 Thrust bearing 4 Gasket 5,7 Pipe 6,8 Body

Claims (2)

(57) [Claims] 1. A cap nut having a female screw formed on the inside, a pipe having a mirror-finished surface on an end face, and abutting on an inner end face of the cap nut to prevent the cap nut and the pipe from rotating together. A co-rotation preventing means, a ferrule attached to an outer periphery of the pipe, abutting on the co-rotation preventing means, and transmitting a thrust force of the cap nut in the pipe longitudinal direction to the pipe; and a ferrule fitted to an end of the pipe. A gasket with which the entire circumference of the end face of the pipe abuts; and a body having a mirror-finished surface on the end face and a male screw formed on the outer circumference, wherein the end face of the body is a face of the gasket with which the pipe abuts. Wherein the male screw of the body and the female screw of the cap nut are fastened with a predetermined torque. 2. A cap nut having a female screw formed on the inside, a first pipe having a mirror-finished surface on an end face, and the cap nut and the first pipe abutting on an inner end face of the cap nut to rotate together. A first counter-rotation preventing means for preventing the rotation of the cap nut, abutting on the first counter-rotation preventing means, abutting on the first counter-rotation preventing means, and transmitting a thrust force of the cap nut in the pipe longitudinal direction to the first pipe. A first ferrule, a body having an external thread formed on an outer periphery thereof, a second pipe having a mirror-finished surface on an end face, and the cap nut and the second pipe rotating in contact with an end face of the body. A second counter-rotation preventing means, which is attached to the outer periphery of the second pipe, abuts against the second counter-rotation preventing means, and transmits the thrust of the cap nut in the pipe longitudinal direction to the second pipe. Two ferrules and the first pie Or a gasket fitted to the end of the second pipe, the entire circumference of the first pipe end face and the second pipe end face abutting from both sides, and the male screw of the body and the female screw of the cap nut Is coupled with a predetermined torque.