JPH0614623U - Sealing mechanism for high vacuum equipment - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a sealing mechanism for high vacuum equipment which does not leak from the seat surface and can be repeatedly used. [Structure] The sealing mechanism 10 includes a pair of sealing surfaces 11, 1.
2, a spring 14 in which a metal wire is spirally wound to be an endless spring, and a jacket 15 for covering the spring 14, the jacket 15 has a seal portion 16 and a mounting portion 17 radially outward thereof. Further, the seal portion 16 has a seat surface 16b where the compression surface 16a of the spring 14 and the seal surface 12 are in pressure contact with each other, and the thickness of the seal portion 16 is such that a wavy undulation is not generated on the seat surface 16b by the compression force compressing the spring 14. The mounting portion 17 whose tip portion is hermetically welded to the sealing surface 11 is
It has a thickness that is elastically deformed by the compressive force. [Effect] Since wavy undulations do not occur on the seat surface due to compression, leakage from the seat surface can be prevented.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a sealing mechanism for high vacuum equipment.

[0002]

[Prior art]

 A metal C ring is usually used as a seal material for the seal of high vacuum equipment. As shown in FIG. 5, the known metal C ring 1 is an endless spring formed by spirally winding a metal wire rod. 2 and a jacket 3 made of a thin metal plate that covers the spring 2 and has a C-shaped cross section. The metal C-ring 1 cannot exert a sufficient reaction force of the spring 2 until the spring 2 comes into contact with the groove 4a formed on the sealing surface 4 of the high vacuum device by compression, so that the spring 2 can be applied with a large force. It is necessary to compress and increase the amount of compression. However, since the thickness of the jacket 3 of the known metal C ring 1 is thin, when the compressive force is increased, the spring 2 may dig into the jacket 3 and cause a wavy undulation on the surface (sheet surface) of the jacket 3. This swell causes leaks. Further, if the metal C ring 1 that has been decompressed is subjected to a baking treatment (heating in a vacuum), the waviness is increased, so that there is a problem that it cannot be used repeatedly.

In order to solve this problem, it is conceivable to increase the wall thickness of the jacket 3, but the jacket 3 is made by forming a flanged cylinder 3a shown in FIG. Since the spring 2 is wound around the spring 2 by molding or spatula drawing to have a C-shaped cross section, there is a limit to its thickness. In particular, when the wire diameter of the spring is small, the wall thickness of the jacket 3 is increased. Is impossible.

[0004]

[Problems to be solved by the device]

 The problem to be solved by the present invention is to provide a sealing mechanism for a high-vacuum device that does not leak from the seat surface and can be used repeatedly.

[0005]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, a sealing mechanism for a high vacuum device according to the present invention has a pair of sealing surfaces and an endless spring formed by spirally winding a metal wire rod inserted in a groove formed in one of the sealing surfaces. A seal mechanism having a seat surface on which the compression surface of the spring and the other seal surface opposite to the compression surface of the spring are in pressure contact. A spring that integrally extends radially outward of the seal portion and has a tip portion airtightly attached to one of the seal surfaces, the seal portion acting on the pair of seal surfaces. It is characterized in that the mounting surface has a thickness such that a wavy undulation does not occur on the seat surface due to a compressive force for compressing, and the mounting portion has a thickness that can be elastically displaced by the compressive force. Further, in order to solve the same problem, a pair of sealing surfaces, an endless spring formed by spirally winding a metal wire rod inserted in a groove formed in one of these sealing surfaces, and a pair of covering them. A sealing mechanism for high vacuum equipment comprising a jacket, wherein these jackets have a sealing portion having a seat surface against which the compression surface of the spring and the other sealing surface on the opposite side are pressed, and the sealing portion. And a mounting portion integrally extending outward in the radial direction of the portion, the tip portions of which are airtightly fixed to each other, and these sealing portions are compressed by the compression force for compressing the springs acting on the pair of sealing surfaces. It is characterized in that the seat surface has a thickness that does not allow wavy undulations, and these mounting portions have a thickness that allows elastic displacement by the compressive force.

[0006]

[Action]

 When the pair of seal surfaces are pressed against each other, the seal part provided on the jacket compresses the spring by elastic displacement of the thin mounting part whose tip part is fixed to one of the seal faces, or The seal portion compresses the spring by the elastic displacement of the thin-walled mounting portion whose tip portions are fixed to each other, so that the pair of seal surfaces is hermetically sealed by the jacket. In this case, since the seal part has a thickness that does not cause wavy undulations on the seat surface due to the compression force for compressing the spring, there is no leakage from the seat surface and it can be used repeatedly. it can.

[0007]

【Example】

 FIG. 1 shows a first embodiment of the present invention, in which a sealing mechanism 10 for high vacuum equipment is inserted into sealing surfaces 11 and 12 to be sealed by pressure contact and an endless groove 13 formed in the sealing surface 11. In addition, a spring 14 that is made by winding a metal wire in a spiral shape and is made endless, and a jacket 15 that covers the spring 14 are provided.

The jacket 15 includes a seal portion 16 that covers the upper surface of the spring 14, and a mounting portion 17 that is integrally extended outward in the radial direction of the seal portion 16, and the spring 14 is attached to the seal portion 16. A compression surface 16a for compression and a seat surface 16b with which the seal surface 12 on the opposite side is in pressure contact are formed. The seal portion 16 has a thickness such that the wavy undulation due to the spring 14 does not occur on the seat surface 16b due to the compressive force for compressing the spring 14, and the mounting portion 17 is elastic by the compressive force. The tip portion is welded to the outer periphery of the sealing surface 11 having a thickness that is displaced. The seat surface 16b is formed into an arc surface having a large diameter, and the compression surface 16a is formed into an arc surface having a diameter larger than the diameter of the spring 14. However, the seat surface 16b may be flat as shown in FIG.

In the sealing mechanism 10, the spring 14 is inserted into the groove 13, the spring 14 is covered by the sealing portion 16 of the jacket 15, and the tip end portion of the mounting portion 17 is welded to the outer periphery of the sealing surface 11 so as to weld them. Unify. Next, the sheet surface 16b is subjected to the machining necessary for sealing. In this sealing mechanism 10, after the jacket 15 is attached to the sealing surface 11, the sheet surface 16b can be machined as necessary for sealing. It can be vacuum sealed. According to experiments, the known metal C-ring 1 requires a surface pressure of about 200 Kgf / cm ² for sealing, but the sealing mechanism 10 can reduce the surface pressure to 1/4 or less. it can. Further, by performing mirror finishing (Rmax 0.8 μm or less) on the sheet surface 16b, it is possible to obtain a high degree of airtightness with a smaller surface pressure.

FIG. 3 shows a second embodiment of the present invention, and this sealing mechanism 20 is constructed by sandwiching both sides of the spring 14 with jackets 21 and 21. The seal portion 22, compression surface 22a, seat surface 22b and mounting portion 23 of the jacket 21 are the same as the seal portion 16, compression surface 16a, seat surface 16b and mounting portion 17 of the jacket 15 of the first embodiment. It has a structure, and the attachment portions 23, 23 are fixed to each other by welding at the tip portion. The sealing mechanism 20 of the second embodiment is the same as that of the first embodiment, except that the seat surfaces 22b, 22b of the respective seal portions are brought into pressure contact with the seal surfaces 11, 12.

FIG. 4 shows an example of a high vacuum valve 30 provided with the above-mentioned sealing mechanism. The valve body 31 of this valve has a port 32, and the flange member 33 hermetically attached to the valve body 31 has a port 34. A valve seat 35 is formed in the flow path which has the respective ports 32 and 34 and communicates these ports 32 and 34, and between the valve body 31 and the bonnet 36 mounted on the side opposite to the port of the valve body 31, The peripheral edge of the metal bellows plate 37 is clamped. A valve rod 39 having an intermediate portion screwed to the bonnet 36 has a valve base 40 and a valve body 41 rotatably attached to one end thereof, and a space between the valve base 40 and the metal bellows plate 37 is It is hermetically sealed by a metal bellows 42, and the sealing mechanism 10 or 20 is mounted between the valve body 31 and the metal bellows plate 37 and on the valve seat side of the valve body 41, respectively. When the valve rod 39 of the valve 30 is rotated, the sealing mechanism 10 or 20 attached to the valve body 41 presses the valve seat 35 to seal the flow passage.

[0012]

EFFECTS OF THE INVENTION The sealing mechanism of the high vacuum equipment according to the present invention is such that the sealing portion of the jacket has a thickness that does not cause a wavy undulation on the seat surface due to the compression force for compressing the spring. Since there is no wavy undulation, it is possible to reliably prevent leakage from the seat surface, and it can be used repeatedly even after releasing the compression force. Also, since the seat surface can be processed after the jacket is fixed to the sealing surface of the device, the seat surface can be easily processed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a first embodiment.

FIG. 2 is a sectional view showing a main part of the same modified example.

FIG. 3 is a half longitudinal sectional view of a second embodiment.

FIG. 4 is a cross-sectional view showing a state applied to a high vacuum valve.

FIG. 5 is a cross-sectional view showing a main part of a known metal C ring in use.

FIG. 6 is a cross-sectional view of a known jacket in an intermediately processed state.

[Explanation of symbols]

 10, 20 Sealing mechanism 11, 12 Sealing surface 14 Spring 15, 21 Jacket 16, 22 Sealing part 17, 23 Mounting part 16a, 22a Compressing surface 16b, 22b Seating surface

Claims (2)

[Scope of utility model registration request] 1. A high-vacuum device comprising a pair of sealing surfaces, an endless spring formed by spirally winding a metal wire inserted in a groove formed in one of the sealing surfaces, and a jacket covering the spring. The seal mechanism, wherein the jacket has a seal portion having a seat surface on which the compression surface of the spring and the other seal surface on the opposite side are in pressure contact, and the jacket integrally extends outward in the radial direction of the seal portion. And the tip portion is provided with an attachment portion airtightly attached to one of the sealing surfaces, and the sealing portion causes a wavy undulation on the seat surface by a compression force for compressing a spring acting on the pair of sealing surfaces. A sealing mechanism for high vacuum equipment, wherein the mounting portion has a thickness that cannot be elastically displaced by the compressive force, respectively. 2. A high end provided with a pair of sealing surfaces, a spring formed by winding a metal wire inserted in a groove formed in one of the sealing surfaces into an endless spring, and a pair of jackets covering the spring. A sealing mechanism for a vacuum device, wherein these jackets are integrally formed with a seal portion having a seat surface on which the compression surface of the spring and the other seal surface on the opposite side are in pressure contact, and radially outward of the seal portion. And a mounting portion whose front end portions are fixed to each other in an airtight manner, and these sealing portions cannot generate wavy undulations on the seat surface due to the compression force for compressing the spring acting on the pair of sealing surfaces. A sealing mechanism for high-vacuum equipment, characterized in that the mounting portions have thicknesses that can be elastically displaced by the compressive force.