JPH039549Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a self-pressurizing gasket used for sealing pressure-resistant stationary parts of various containers and equipment.

[Conventional technology]

Conventionally, this type of gasket has been used as an example, as shown in FIG. It is known that two annular lips 3 and 4 symmetrical to each other are formed independently and integrally. Each annular lip 3,4 constitutes a sealing surface 5,6 on the outside of its tip, both sealing surfaces 5,6
The interval W ₁ is set larger than the width W ₂ of the annular base 1 . This gasket is generally made of metal, and the sealing surfaces 5, 6 or the entire surface of the gasket is coated or plated with a soft sealing material (film) as required.

FIG. 6 shows an example of the use of the above gasket, in which the gasket is interposed between the upper and lower connecting members 7 and 8 when they are fastened together with bolts 9. When the bolt 9 is tightened until the screws ', 1' contact the connecting members 7, 8, both annular lips 3, 4 will close the gap between the sealing surfaces 5, 6.
It bends inward from W ₁ to W ₂ , and the reaction force at this time acts on the seal surfaces 5 and 6 as an initial load at the time of installation. When the fluid to be sealed is sent into the case constituted by the connecting members 7 and 8,
Fluid pressure acts on the back surfaces of the annular lips 3, 4 from the groove 10 between the two annular lips 3, 4, and the force generated by the pressure difference with the lip outer spaces 11, 12, which have a relatively low pressure, is applied to the sealing surface. The structure is such that the seal surface load increases as the pressure increases (self-pressure increasing type).

[Problem that the invention attempts to solve]

As described above, this type of gasket has the feature of effectively utilizing the working pressure of the fluid to be sealed to achieve a complete seal, but as pressure increases and high heat occurs, the connecting members 7 and 8 themselves If the deformation occurs, it is conceivable that the annular lips 3, 4 will not be able to follow this deformation. That is, as shown in FIG. 7, one connecting member 7 has a lid shape.
When the upper annular lip 3 deforms significantly, the upper annular lip 3, which is structured to follow the deformation independently, reaches its limit of following at an early stage, and a gap is created between the sealing surface 5 and the lower surface of the connecting member 7, and a large amount of fluid flows through this gap. leak.

[Means for Solving the Problems] In view of the above points, the present invention was developed with the aim of increasing the following ability of the annular lip and improving the sealing performance. A metal gasket having an annular base clamped between connecting members and a bifurcated annular lip that presses against the connecting member, the thin wall being bent in a concentric wave shape between the annular base and the annular lip. The structure is such that a connecting portion is formed.

[Effect]

That is, the gasket of the present invention has two annular lips connected at their base ends to form a bifurcated shape.
This is connected to the annular base via a thin connecting part bent into a concentric wave shape that easily deforms, and when the connecting member is deformed, the entire annular lip including the connecting part moves accordingly. It becomes like this.

〔Example〕

Next, embodiments of the gasket of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 21 indicates an annular base having a substantially rectangular cross section and having a required number of bolt insertion holes 22 in the circumferential direction. An annular lip 23,
24 are integrally molded via a thin connecting portion 27 bent in a concentric wave shape. Annular lip 23,2
Seal surfaces 25 and 26 are formed on the outside of the tip of the ring 4, and the distance W ₃ between the seal surfaces 25 and 26 is set larger than the width W ₄ of the annular base 21 . The gasket is made of a metal material as in the conventional example, and the sealing surfaces 25, 26 or the entire surface are coated or plated with a soft sealing material (film) as required.

FIG. 2 shows a state in which the gasket is attached, corresponding to FIG. 6 according to the conventional example. From this state, when the pressure of the sealing liquid sent into the case increases and the upper connecting member 7 deforms as shown in FIG. 3, the annular base 21 The entire bifurcated annular lips 23 and 24 connected to each other, including the connecting portion 27, follow the movement. That is, when the upper annular lip 23 follows the deformation of the connecting member 7 and actually moves by the same amount, the wave-shaped connecting portion 27 is easily deflected and displaced by the repulsive force of the lower annular lip 24. The proximal end portions 28 of the bifurcated annular lips 23 and 24 are displaced upward (from P ₁ to P ₂ in the figure) while keeping the groove portion 10 oriented substantially horizontally.

For the same purpose, it is conceivable to form a thin constriction 27a between the annular lips 23, 24 and the annular base 21 as shown in FIG. 4, but in this case, the constriction 27a There is no follow-up displacement of the lip itself, and both annular lips 2
In order for the annular lips 23 and 24 to bend almost equally, the constriction 27 including the proximal ends 28 of both annular lips 23 and 24 must be
a must be deformed in a tapered manner at an angle θ, and such a deformation is unlikely to occur in the gasket made of metal. There is a tendency to lean toward Lip 23. In this regard, according to the configuration of the above embodiment, as described earlier, the flexure of the wave-shaped connecting portion 27 causes the annular lips 23, 2 to
Since the proximal end portion 28 of the connecting member 7 is displaced from P ₁ to P ₂ , both the annular lips 23 and 24 are deflected almost equally, and can follow the deformation of the connecting member 7 well to maintain sealing performance. I can do it.

[Effect of idea]

As explained above, the self-pressurizing gasket of the present invention consists of a thin-walled gasket having an annular base clamped between connecting members connected to each other, and a bifurcated annular lip that presses against the connecting members, bent in a concentric wave shape. In the conventional technology, even if deformation occurs to the extent that the sealing function is lost, the proximal end of the annular lip itself will follow the deformation of the mating member due to the flexure of the corrugated connecting portion. Therefore, the same degree of deflection is always applied to the bifurcated annular lip to maintain the same sealing load on both sides, and the load is not unevenly distributed unlike the conventional technology in which the following action is left to one lip. , it is possible to eliminate problems such as one lip becoming fatigued first.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the main part of a gasket according to an embodiment of the present invention, Figs. 2 and 3 are sectional views showing how the same gasket is used, and Fig. 4 is a sectional view of the main part showing a comparative example of the same gasket. 5 are sectional views of essential parts of a conventional gasket, and FIGS. 6 and 7 are sectional views showing how the same gasket is used. 1, 21... Annular base, 2, 22... Bolt insertion hole, 3, 4, 23, 24... Annular lip, 5,
6, 25, 26... Seal surface, 7, 8... Connecting member, 9... Bolt, 10... Groove, 11, 12...
...outer space, 27...connection section.

Claims (1)

[Scope of utility model registration request] A metal gasket having an annular base sandwiched between connecting members that are connected to each other and a bifurcated annular lip that presses against the connecting member, the gasket having a concentric wave shape between the annular base and the annular lip. A self-pressurizing gasket characterized by forming a thin-walled connecting portion bent in the direction of the gasket.