JP2008025720A - Sealing construction of valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing construction of a valve which can prevent sealing elements from being damaged by suppressing a generation of sticking out phenomenon in the sealing elements in the sealing construction of the valve having a construction of allowing a pair of sealing elements to getting into contact with or being separated from each other in tune with opening/closing movement of the valve. <P>SOLUTION: A pair of sealing elements is a combination of a rigid component of metal or the like and a rubbery elastic body 2 on the surface of which a rigid material layer 3 of metal or the like is coated. The surface of the rigid material layer 3 may be coated with a membrane-like rubber layer, and a space portion for enlarging the allowance for collapse of the rubbery elastic body 2 at the time of valve closure may be set in a bottom portion of an attaching groove 4a of a retaining member for attaching the rubbery elastic body 2 or the bottom of the rubbery elastic body 2 facing the bottom portion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a valve seal structure in which a pair of seal elements come in contact with and separate from each other in accordance with the opening and closing operation of the valve. The seal structure of the present invention is used, for example, in an opening / closing operation part of a high pressure gas valve for a fuel cell.

  In the conventional valve device 51 shown in FIG. 6, when the valve is closed, as shown in FIG. 7 (A), the valve body 52 made of a metal part which is one sealing element has a rubber lip (outside) which is the other sealing element. The seal portion 53 and the metal portion (inner seal portion) 54 are sequentially abutted, that is, the seal portion 53 and the metal portion 54 are abutted first.

  However, according to this structure, as the gas pressure to be sealed is increased, the rubber lip 53 is pushed by the pressure and deforms to cause a protrusion phenomenon. Therefore, as shown in FIG. And the metal part 54 may be damaged.

JP-A-9-150728

  In view of the above, an object of the present invention is to provide a valve seal structure that can suppress the occurrence of a protruding phenomenon in a seal element and can prevent the damage.

  In order to achieve the above object, a seal structure according to claim 1 of the present invention is a valve seal structure in which a pair of seal elements come in contact with and separate from each other in accordance with the opening / closing operation of the valve. It is a combination of a rigid part such as a rubber-like elastic body with a surface of a hard material layer such as metal.

  The seal structure according to claim 2 of the present invention is characterized in that, in the seal structure according to claim 1 described above, a thin rubber layer is adhered to the surface of the rigid material layer.

  The seal structure according to claim 3 of the present invention is the seal structure according to claim 1 or 2, wherein the rubber facing the bottom surface portion of the mounting groove of the holding member for mounting the rubber-like elastic body or the bottom surface portion. The bottom surface of the elastic body is provided with a space for expanding the crushing margin of the rubber-like elastic body when the valve is closed.

  As in the sealing structure according to the first aspect of the present invention having the above-described configuration, a rubber-like elastic material in which a rigid material layer such as metal is attached to the surface as a sealing element combined with a rigid component such as metal instead of a conventional rubber lip. When the body is used, the rubber-like elastic body is hard to elastically deform because its surface is covered with a rigid material layer such as metal, and therefore does not elastically deform so much as to cause a protrusion phenomenon even when high pressure is applied. . That is, if the rubber-like elastic body is a single body, there is a risk that it will be greatly elastically deformed when a high pressure is applied to cause a protrusion phenomenon and breakage. Since it is coated, it is less likely to be elastically deformed than when it is not coated, so that it is not greatly deformed even when high pressure is applied. Also, if the rigid material layer such as metal is a single body, there is a risk that it will be greatly deformed and damaged when high pressure is applied, but in the present invention, the rigid material layer is lined with a rubber-like elastic body. Therefore, it is harder to be deformed than when it is not lined, so it will not be greatly deformed even when high pressure is applied. As an aspect, it is preferable to apply a thin plate-like rigid material layer made of stainless steel or the like on the surface of a rubber-like elastic body made of ethylene / propylene / diene rubber (EPDM) or fluorine rubber (FKM).

  In addition to this, when a thin rubber layer is deposited on the surface of the rigid material layer as in the seal structure according to claim 2 of the present invention, the rigid material layer comes into contact with the contact partner (rigid component). Instead, the thin rubber layer comes into contact with the counterpart, and the thin rubber layer is sandwiched between the rigid material layer and the counterpart.

  Further, as in the seal structure according to claim 3 of the present invention, when a space portion is provided on the bottom surface portion of the mounting groove of the holding member for mounting the rubber elastic body or the bottom surface of the rubber elastic body facing this bottom surface portion, Since this space portion is used as a relief space when the rubber-like elastic body is elastically deformed, a crushing margin of the rubber-like elastic body when the valve is closed is set large.

  The present invention has the following effects.

  That is, in the seal structure according to the first aspect of the present invention, as described above, the rubber-like elastic material in which a rigid material layer such as a metal is attached to the surface as a sealing element combined with a rigid component such as a metal instead of a conventional rubber lip. Since the body is used, the rubber-like elastic body is not elastically deformed so much as to cause a protrusion phenomenon even when a high pressure is applied. Therefore, the sticking phenomenon of the sealing element which has occurred conventionally can be suppressed, and the breakage thereof can be prevented.

  In addition to this, in the sealing structure according to claim 2 of the present invention, since the thin rubber layer is deposited on the surface of the rigid material layer, the thin rubber layer is not the other material. The thin rubber layer is sandwiched between the rigid material layer and the counterpart in a compressed state. Therefore, it is possible to further improve the sealing performance when the valve is closed by effectively using the elasticity of the thin rubber layer. Since the rubber layer is in the form of a thin film and is attached to the rigid material layer, the protruding phenomenon does not occur like a conventional rubber lip.

  In the seal structure according to claim 3 of the present invention, a space is provided on the bottom surface of the mounting groove of the holding member for mounting the rubber-like elastic body or on the bottom surface of the rubber-like elastic body facing the bottom surface. For this reason, the amount of crushing of the rubber-like elastic body when the valve is closed is set large by the amount of the space provided. Accordingly, since the rubber-like elastic body is greatly elastically deformed when the valve is closed and a large elastic repulsive force is generated, the large repulsive force can be effectively used to further improve the sealing performance when the valve is closed. it can.

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

First embodiment ...
FIG. 1 shows a valve seal structure according to a first embodiment of the present invention.

  In the seal structure according to the embodiment, a pair of seal elements come in contact with and separate from each other in accordance with the opening / closing operation of the valve, and the pair of seal elements includes a valve body 1 that is a rigid part such as metal, and a valve It is configured by a combination with a rubber-like elastic body 2 in which a rigid material layer 3 such as metal is attached to the surface 2a on the seat side. The latter rubber-like elastic body 2 with the rigid material layer 3 applied to the surface 2a is mounted in a mounting groove 4a provided in the valve body 4 as a holding member.

  A rubber-like elastic body (also referred to as a seal main body) 2 is formed in a ring shape from a predetermined rubber material such as EPDM or FKM, and is formed in a substantially D-shaped cross section as shown in the figure, and has one curved surface in the axial direction. 2a and the other planar bottom surface (back surface) 2b in the axial direction. The former curved surface 2a is formed to have a substantially arcuate or substantially U-shaped cross section.

  A rigid material layer (also referred to as a metal layer or a metal fitting depending on the material) 3 is formed into an annular shape by a predetermined rigid plate made of a metal such as stainless steel or a resin, and is covered over the entire surface 2 a of the rubber-like elastic body 2. It is worn. Accordingly, the rigid material layer 3 has a substantially arcuate or substantially U-shaped cross section, like the surface 2 a of the rubber-like elastic body 2. The deposition is performed by means such as adhesion or baking. Since the rigid material layer 3 has a thin plate shape, it can be elastically deformed. When the rigid material layer 3 is mounted in the mounting groove 4a, the convex side of the arc protrudes to the outside of the mounting groove 4a, so that the valve body 1 comes in contact with and separates from the top end portion of the convex side protruding portion. The material layer 3 is a contact portion 3a.

  On the other hand, the valve body 1 is formed of a rigid material such as a metal or a hard resin, and has a contact surface 1a having a plane perpendicular to the axis at a part thereof.

  FIG. 1 shows a valve open state, in which high pressure gas flows from the high pressure side space H to the low pressure side space L. A seal body made of a rubber-like elastic body 2 having a surface of a hard material layer 3 made of metal or the like deposited on the surface 2a is hermetically mounted in the mounting groove 4a and faces the valve body 1. When the valve is closed from this open state and the valve body 1 moves in a direction approaching the valve body 4, the contact surface 1 a of the valve body 1 contacts the contact portion 3 a of the rigid material layer 3. The layer 3 and the rubber-like elastic body 2 are elastically deformed to realize a sealed state in which the valve is closed. The elastically deformed rigid material layer 3 and the rubber-like elastic body 2 are strongly pressed against the valve body 1 by its elastic repulsive force.

  The seal structure of the above configuration uses a rubber-like elastic body 2 in which a rigid material layer 3 such as metal is attached to the surface 2a instead of the conventional rubber lip as a sealing element combined with the valve body 1 which is a rigid part such as metal. The rubber-like elastic body 2 has a surface 2a covered with a rigid material layer 3 such as a metal, so that it is not easily elastically deformed. There is no elastic deformation. Since the thin plate-like rigid material layer 3 is lined by the rubber-like elastic body 2, it is not elastically deformed so much. Therefore, the sticking phenomenon of the sealing element which has conventionally occurred can be suppressed, and the breakage thereof can be prevented.

  Further, according to this structure, when the valve is closed, the rigid material layer 3 and the rubber-like elastic body 2 are elastically deformed, so that a relatively large elastic repulsive force is generated in combination. Therefore, since the rigid material layer 3 is strongly pressed against the valve body 1 by this large repulsive force, the close contact force is increased, and thus excellent sealing performance can be exhibited.

Second embodiment ...
Still, when both the valve body 1 and the rigid material layer 3 are made of metal, a so-called metal touch (contact between metals) may occur and a slight leakage may occur due to the surface roughness of the metal surface. When it is necessary to eliminate the problem, it is preferable to apply a thin rubber layer 5 as a seal layer on the surface of the rigid material layer 3 as shown in FIG.

  The rubber layer 5 is formed into a thin film from the same or different rubber material as the rubber-like elastic body 2, and is applied over the entire surface of the rigid material layer 3. A contact portion 5 a is set at the top end portion of the rubber layer 5. The deposition is performed by means such as adhesion or baking, but the coating method is suitable because the rubber layer 5 is in the form of a thin film.

  According to this structure, since the thin rubber layer 5 is attached to the surface of the rigid material layer 3, the rubber layer 5 contacts the valve body 1 which is a contact partner instead of the rigid material layer 3, At this time, the rubber layer 5 is sandwiched between the rigid material layer 3 and the valve body 1 in a compressed state. Therefore, the elasticity of the rubber layer 5 is effectively utilized and the surface roughness of the metal surface is substantially canceled, so that the sealing performance when the valve is closed can be further improved. Since the newly provided rubber layer 5 is in the form of a thin film and is attached to the rigid material layer 3, it does not cause an overflow phenomenon.

Third embodiment ...
Further, in the first and second embodiments, the bottom surface portion 4b of the mounting groove 4a of the valve body 4 to which the rubber-like elastic body 2 is mounted is set in a planar shape perpendicular to the axis, as shown in FIG. Thus, when the space portion 6 is provided in the bottom surface portion 4b of the mounting groove 4a, the space portion 6 can be used as a clearance space for the rubber-like elastic body 2, so that the rubber-like elastic body 2 is closed when the valve is closed. It is possible to set a large crushing margin. Accordingly, since the rubber-like elastic body 2 is greatly elastically deformed when the valve is closed and a large elastic repulsive force is generated, the large repulsive force is effectively used to further improve the sealing performance when the valve is closed. Can do. The space portion 6 is formed as an annular groove in the bottom surface portion 4b of the mounting groove 4a.

Fourth embodiment ...
Moreover, this space part 6 may be provided in the bottom face 2b of the rubber-like elastic body 2, as shown in FIG. 4, and in this case, the same function and effect as in the third embodiment can be obtained. The space 6 is formed as an annular groove on the bottom surface 2 b of the rubber-like elastic body 2.

Fifth Example ...
In each of the above embodiments, the mounting groove 4a provided in the valve body 4 which is a holding member is a rectangular groove having a rectangular cross section. However, as shown in FIG. Then, the effect of preventing omission can be obtained. In this case, at the time of mounting work, the rubber-like elastic body 2 to which the rigid material layer 3 is applied is mounted in a state in which the radial width is reduced by compressing in the radial direction. After the mounting, when the rubber-like elastic body 2 to which the rigid material layer 3 is applied is elastically restored in the radial direction, the front end portion (lower end portion in the figure) of the rigid material layer 3 expands in a square shape and the side surface of the mounting groove 4a. Since it engages with the part 4c, it will be difficult to come off even if a high pressure is applied after it has been applied.

  Other configurations and operational effects of the second to fifth embodiments are the same as those of the first embodiment. Therefore, the same reference numerals are attached to the drawings, and the description is omitted.

  Furthermore, in each of the above embodiments, a rigid part such as metal forms the valve body of the valve, and a rubber-like elastic body with a rigid material layer forms the valve seat side of the valve. A rigid part such as the above may form the valve seat side of the valve, and a rubber-like elastic body with a rigid material layer may form the valve body side of the valve. In this case, the rubber-like elastic body to which the rigid material layer is applied advances and retreats with respect to the rigid component such as metal.

Sectional drawing of the principal part of the seal structure which concerns on 1st Example of this invention. Sectional drawing of the principal part of the seal structure which concerns on 2nd Example of this invention. Sectional drawing of the principal part of the seal structure which concerns on 3rd Example of this invention. Sectional drawing of the principal part of the seal structure which concerns on 4th Example of this invention. Sectional drawing of the principal part of the seal structure which concerns on 5th Example of this invention. Sectional view of a valve device according to a conventional example Sectional view of the seal structure provided in the valve device

Explanation of symbols

1 Valve body (rigid parts)
DESCRIPTION OF SYMBOLS 1a Contact surface 2 Rubber-like elastic body 2a Surface 2b Bottom surface 3 Rigid material layer 3a, 5a Contact part 4 Valve body 4a Mounting groove 4b Bottom surface part 4c Side surface part 5 Rubber layer 6 Space part H High-pressure side space L Low-pressure side space

Claims (3)

In the valve seal structure in which the pair of seal elements come in contact with each other in accordance with the opening and closing operation of the valve,
The pair of sealing elements is a combination of a rigid part such as metal and a rubber-like elastic body having a surface of a rigid material such as metal attached thereto. The seal structure according to claim 1,
A valve seal structure, characterized in that a thin rubber layer is deposited on the surface of a rigid material layer. The seal structure according to claim 1 or 2,
A space for expanding the crushing margin of the rubber-like elastic body when the valve is closed on the bottom surface of the mounting groove of the holding member for attaching the rubber-like elastic body or the bottom surface of the rubber-like elastic body facing the bottom surface A valve seal structure characterized in that is provided.

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