JPH0666373A - Metal gasket - Google Patents

Abstract

PURPOSE:To provide a metal gasket requiring no special spacer plate, easy to center, and easy to handle. CONSTITUTION:A metal gasket is formed with a metal into a ring shape as a whole, the cross section of the portion forming a ring section 2 has a bent shape, and retainers 3 are integrally formed on the periphery of the ring section 2. When the ring section 2 is pinched by jointing members, the bent section is deformed, thus the sealing property can be maintained, the ring section 2 can be hooked on the jointing members by the retainers 3, positioning is facilitated, and centering is simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal gasket which is provided at a place where parts are connected to each other in various fluid systems to maintain gas-liquid tightness.

[0002]

2. Description of the Related Art In various fluid systems, a gasket is provided in order to hermetically seal the joint surface of fluid equipment and pipes when they are connected. The most commonly used gasket is an O-ring. The well-known O-ring is made of a soft material such as rubber or resin. However, this O-ring has a physical and chemical property that makes it suitable for locations where thermal deterioration and chemical changes easily occur. It cannot be used, and in such a case, a metal O-ring may be used. For example, in the manufacturing process of semiconductor devices, particularly in the wafer processing process, it is strongly required to eliminate factors that adversely affect the device characteristics. Therefore, the impurity content of the supplied gas is required to be extremely small. Therefore, in addition to individual components in the gas flow system, in order to minimize the occlusion and release of impure gas, special internal surface polishing such as electrolytic polishing or chemical polishing is applied to the entire inner surface of the flow path. Various improvements have been made. The seal structure used in the gas flow system in such a background avoids the use of rubber or resin O-rings, which are liable to chemically change or deteriorate due to a large amount of occlusion and release of impure gas, and have a high gas purity. The use of a metal gasket that can be kept at is desirable. Therefore, recently, metal O-rings are often used in the gas distribution system of this type of wafer processing process.

However, the metal O-ring is rarely used alone, and when the metal O-ring and the spacer plate made of a softer metal are used in an overlapping manner and the joining members are fastened together with the fastening bolts,
The metal O-ring and the spacer plate are sandwiched between the joining members, and the metal O-ring is brought into close contact with the spacer plate by the elastic or plastic deformation of the spacer plate, thereby maintaining the seal.

[0004]

However, such a seal structure using a metal O-ring has a drawback that the number of parts increases because it is necessary to use a special spacer plate as described above.

Further, according to such a metal O-ring, it is difficult to center the fluid passage and when the metal O-ring is disassembled for maintenance and seal-joined again, the metal O-ring is used.
There is a case where the ring is displaced from the initial sealing position and is particularly eccentrically mounted, and in such a case, there is a problem that leakage tends to occur due to the fact that the initial mounting trace remains.

The present invention has been made in view of the above circumstances, and its purpose is to eliminate the need for a special spacer plate, to facilitate centering, and to prevent eccentricity when resealing. The purpose is to provide a metal gasket that is easy to handle.

[0007]

The present invention is made of metal and has a ring shape as a whole, and a cross section of a portion forming the ring portion is bent, and a retainer is provided around the ring portion. Is formed integrally.

[0008]

According to the present invention, when the metal gasket of the present invention is sandwiched between the joining members, the bent portion of the ring portion is pressed and deformed, so that the sealability can be maintained, and the retainer can be used to engage the joining members. Since it can be stopped, alignment is easy and centering is easy.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in FIGS. FIG. 1 shows a metal gasket according to the present invention. This metal gasket 1
A ring portion 2 made of a metal such as nickel or stainless steel and continuous in the circumferential direction, and a plurality of (three in the figure) retainers 3 provided along the circumferential direction of the ring portion 2 are provided.

The ring portion 2 is formed by bending a tube having a circular cross section into a ring shape. However, since this metal gasket is integrally formed by punching, drawing, curling, etc., it is not made by making a tube in advance and bending it into a ring shape. The tube portion forming the ring portion 2 has a circular cross section,
The tube portion may have a circular shape which is continuous in the circumferential direction, but in the case of this embodiment, it has a non-continuous circular shape which is divided at a part in the circumferential direction.

The retainers 3 ... Extend from the ring portion 2 and are bent along the ring center line direction of the ring portion 2. Therefore, the retainers 3 ... Are elastic tongue pieces. The retainers 3 made of such elastic tongues are engaged with the locking grooves formed in the members to be joined. That is, an example of using the metal gasket 1 as described above will be described with reference to FIGS. 2 and 3.

FIG. 3 shows a gas flow controller 10 used in a gas control device in a semiconductor manufacturing apparatus.
The gas flow controller 10 includes a pedestal 11, a flow rate sensor 12 and a piezoelectric element control valve 13.
Is attached and configured as one, that is, unitized. The piezo-piezoelectric element type control valve 13 includes a piezo-piezoelectric element 131 and a valve body 132 that is opened and closed by the piezo-piezoelectric element 131.

The pedestal 11 has an inlet 14 and an outlet 15
And an inlet flange 20 and an outlet flange 30 are connected to the inlet 14 and the outlet 15, respectively. The inlet flange 20 and the outlet flange 30 are attached to the pedestal 11 with the tightening bolts 4 respectively.
Connected using 0. In this case, the metal gaskets 1 and 1 of the present invention are sandwiched between the pedestal 11 and the inlet flange 20 and the outlet flange 30.

The mounting structure of the metal gasket 1 is shown in FIG.
It will be described with reference to the joint between the pedestal 11 and the inlet flange 20 shown in FIG. The engaging groove 1 having a predetermined diameter is formed on the joint surface facing the pedestal 11 and the inlet flange 20, respectively.
6, 21 are formed. Retainers 3, ..., which are elastic tongues of the metal gasket 1, are detachably attached to either one of the locking grooves 16 and 21.

In the metal gasket 1 having such a structure, as shown in FIG.
It is attached to the joint with 0. In this case, the retainers 3 of the metal gasket 1 are press-fitted into either one of the engagement grooves 16 and 21 formed in the pedestal 11 and the inlet flange 20, respectively, and are elastically attached, whereby the ring portion 2 surrounds the inlet 14. And abuts on the joint surface of the pedestal 11 or the inlet flange 20.

In this state, the base 11 and the inlet flange 20
The joint surfaces of are abutted and tightened with a tightening bolt 40. Then, the ring portion 2 of the metal gasket 1 is pinched by the joint surface between the pedestal 11 and the inlet flange 20, and thereby deformed and comes into close contact with these joint surfaces. In particular, since the portion forming the ring portion 2 is discontinuous in the circumferential direction of the cross section, it is easily elastically deformed, and a large crushing margin occurs with a small tightening force. Therefore, it is possible to reliably prevent the leak at the joint between the pedestal 11 and the inlet flange 20.

In such a metal gasket,
Since the retainer 3 is elastically attached to either one of the engaging grooves 16 and 21 formed in the pedestal 11 and the inlet flange 20,
The centering of the ring portion 2 is facilitated and the assembling work can be saved. Further, since the retainers 3 are elastically attached to the locking grooves 16 and 21 of the pedestal 11 and the inlet flange 20 to lock the metal gasket 1 to the pedestal 11 or the inlet flange 20, until the two joint surfaces are butted. Even if there is no space for holding the metal gasket 1 between the metal gasket 1 and the pedestal 11, it can be easily attached.

Further, even if the joint surfaces are separated due to maintenance and the joining surfaces are separated, the metal gasket 1 does not come off because the retainers 3 are engaged with the pedestal 11 or the inlet flange 20, and the metal gasket 1 is resealed as it is. If
The metal gasket 1 does not deviate from its initial sealing position, and in particular eccentricity does not occur, so that no leak occurs.

Even if the metal gasket 1 is replaced by the above-mentioned maintenance, the retainers 3 ... Are elastically attached to the locking grooves 16 or 21 to align the ring portion 2, so that the ring portion 2 is first aligned. The seal position can be automatically adjusted, and a reliable seal can be maintained. Further, unlike the conventional seal structure using a metal O-ring, it is not necessary to use a spacer plate, so that the number of parts can be reduced.

As described above, compared with the case of using the conventional O-ring, handling and assembling are less required, workability is improved, and the number of parts is reduced, so that the cost can be reduced.

In the above embodiment, the ring portion 2
The case where the portion forming the ring portion has a circular cross section has been described, but the portion forming the ring portion 2 may have a C-shaped cross section as in the other embodiment shown in FIG. .

[0022]

As described above, according to the present invention, when the joint members press the ring portions, the bent portions are deformed and come into close contact with the joint surface, and a high sealing property can be maintained. Further, since the retainer is engaged with the joining member, the ring portion can be easily aligned and the centering is easy. For this reason, no special spacer plate is required, eccentricity is prevented when resealing, and handling is easy.

[Brief description of drawings]

FIG. 1 is a perspective view showing a metal gasket according to an embodiment of the present invention in a partial cross section.

FIG. 2 is a cross-sectional view showing a usage example of the metal gasket of the embodiment.

FIG. 3 is a cross-sectional view of a gas flow controller used in the process gas distribution line according to the embodiment.

FIG. 4 is a sectional view of a metal gasket showing another embodiment of the present invention.

[Explanation of symbols]

1 ... Metal gasket, 2 ... Ring part, 3 ... Retainer,
10 ... Gas flow controller, 11 ... Block, 12
... Flow rate sensor, 13 ... Control valve, 16, 21 ... Locking groove, 20 ... Inlet flange, 30 ... Outlet flange, 40
… Tightening bolts.

Claims (3)

[Claims] 1. A metal-made ring-shaped member, wherein the cross-section of the portion forming the ring portion is bent, and a retainer is integrally formed around the ring portion. And a metal gasket. 2. The metal gasket according to claim 1, wherein a cross section of a portion forming the ring portion is circular or C-shaped. 3. The retainer is formed as a plurality of retainers around the ring portion, each of which is an elastic tongue extending in a direction along a center line of the ring portion.
The metal gasket described in.