JP6573772B2 - Sealing device - Google Patents

Description

The present invention relates to a sealing device according to a sealing technique. The sealing device of the present invention is used, for example, as a fuel cell gasket .

  Conventionally, as shown in FIG. 5A, a gasket 31 is mounted in a mounting groove 13 provided on the facing surface 12 of one member 11 of the two members 11 and 21 facing each other, and the gasket 31 is mounted on the other side. There is known a sealing device 1 that seals between two members 11 and 21 by closely contacting an opposing surface 22 of a member 21. The mounting groove 13 has a rectangular cross section.

Recently, in the field of fuel cells, the groove width dimension w ₁ of the mounting groove 13 in which the gasket 31 is mounted tends to be reduced in order to ensure a large plane area of the reaction surface of the fuel cell stack. On the other hand, when the change in the clearance c of the seal assembling portion is large due to the temperature change from the time of power generation related to the operation of the fuel cell to the time when the fuel cell is left standing, as shown in FIG. The cross-sectional shape needs to be a vertically long shape. Accordingly, since mounting the gasket 31 of the elongated shape in a small mounting groove 13 of the groove width w _1, the gasket 31 is its width w ₂ is much small.

  However, such a vertically long gasket 31 has a disadvantage that the gasket 31 is liable to fall in the mounting groove 13 when the rubber hardness is low. On the contrary, when the rubber hardness is high, the repulsive force of the gasket 31 is large. It may become too much.

  In order to prevent the gasket 31 from falling in the mounting groove 13, as shown in FIG. 6, a protrusion 41 for preventing the falling is provided on the side surface of the gasket 31, and this protrusion 41 is provided on the groove side surface portion 13 c of the mounting groove 13. The technique which contacts is developed (refer patent document 1).

JP 2002-340190 A (FIG. 4)

  However, according to the technique of FIG. 6, in order to integrally provide the protrusion 41 on the side surface of the gasket 31, it is necessary to provide a concave shape for forming the protrusion 41 on the inner surface of the cavity of the rubber mold for forming the gasket 31. Therefore, there is a disadvantage that the cavity shape of the rubber mold becomes complicated.

  In view of the above points, the present invention can cope with a change in the clearance of the seal assembly portion even if the cross-sectional shape of the gasket is not a vertically long shape, and there is no need to provide a protrusion for preventing the collapse on the side surface of the gasket. Another object of the present invention is to provide a sealing device in which the gasket does not fall in the mounting groove.

In order to achieve the above object, the present invention employs the following means.
The sealing device of the present invention is a sealing device that seals between the two members by bringing a gasket mounted in a mounting groove provided in one of two members facing each other into close contact with the other member, A throttle part having a taper shape is provided on the groove side surface on the inner surface of the mounting groove, and a narrow space part is provided on the groove bottom side of the throttle part, and the width dimension of the gasket is made smaller than the minimum groove width dimension of the throttle part. The gasket has a large clearance between the two members when the gasket is placed in a low compression state, and when the gasket is placed in a low compression state with a small clearance between the two members. When the gasket is mounted in a different state and the clearance between the two members is large, the gasket is placed in a low compression state. The ket is pressed against the tapered shape of the throttle portion by the assembly load of the two members to generate a seal surface pressure. At this time, the gasket is not press-fitted into the narrow space portion, and the clearance between the two members is small. When the gasket is placed in a highly compressed state, a part of the gasket is press-fitted into the narrow space portion (Claim 1).

  According to the present invention, when the clearance between the two members is relatively large and the gasket is placed in a low compression state, the gasket is pressed against the tapered shape of the throttle portion by the assembly load of the two members. Therefore, since the gasket is pressed against the tapered shape of the throttle portion in this way, a sealing surface pressure is generated, and thus sealing performance is established.

  On the other hand, when the clearance between the two members is relatively small and the gasket is placed in a highly compressed state, the gasket is partially pressed into the narrow space. Therefore, since a part of the gasket is press-fitted into the narrow space portion in this way, the repulsive force is reduced, so that the repulsive force does not become too large.

  In addition, the gasket is prevented from falling in the mounting groove by press-fitting a part of the gasket into the narrow space portion.

  As the shape of the narrow space part, the groove width dimension is set to be constant from the throttle part side to the groove bottom part side, but not limited to this, the groove width dimension is set to gradually narrow from the throttle part to the groove bottom part. (Claims 2 and 3).

  In the present invention, when the clearance between the two members is relatively large and the gasket is placed in a low compression state, and when the clearance between the two members is relatively small and the gasket is placed in a high compression state, Since the mounting state of the gasket is different, it is possible to cope with a change in the clearance of the seal assembling portion even if the sectional shape of the gasket is not a vertically long shape. In addition, since a part of the gasket is press-fitted into the narrow space portion, it is possible to prevent the gasket from falling in the mounting groove without providing a protrusion for preventing the collapse on the side surface of the gasket.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the sealing device based on 1st Example of this invention, (A) is sectional drawing which shows the state at the time of gasket low compression, (B) is sectional drawing which shows the state at the time of gasket high compression It is a figure which shows the sealing device based on 2nd Example of this invention, (A) is sectional drawing which shows the state at the time of gasket low compression, (B) is sectional drawing which shows the state at the time of gasket high compression It is a figure which shows the sealing device which concerns on 3rd Example of this invention, (A) is sectional drawing which shows the state at the time of gasket low compression, (B) is sectional drawing which shows the state at the time of gasket high compression It is a figure which shows the sealing device which concerns on 4th Example of this invention, (A) is sectional drawing which shows the state at the time of gasket low compression, (B) is sectional drawing which shows the state at the time of gasket high compression (A) And (B) is sectional drawing of the sealing device which concerns on a prior art example Sectional drawing of the sealing device which concerns on another prior art example

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

First embodiment ...
FIG. 1 shows a sealing device 1 according to an embodiment of the present invention. In the sealing device 1 according to this embodiment, the gasket 31 is mounted in the mounting groove 13 provided on the facing surface 12 of one member 11 of the two members 11 and 21 facing each other, and this gasket 31 is the other member 21. The two members 11 and 21 are sealed by being in close contact with the facing surface 22 of the first and second mounting grooves 13 and the gasket 31 are configured as follows. One member 11 is, for example, a separator constituting a fuel cell stack, and the other member 21 is, for example, MEA (membrane electrode assembly) or GDL (gas diffusion layer) combined with the separator.

  The mounting groove 13 has a groove opening 13a, and a throttle part 14 having a tapered shape 15 is provided on the groove bottom 13b side of the groove opening 13a. The tapered shape 15 is provided symmetrically on both groove side surfaces 13 c of the mounting groove 13. The taper direction of the taper shape 15 is such that the groove width dimension gradually decreases from the groove opening 13a side to the groove bottom 13b side.

Further, a narrow space portion 16 having a groove width smaller than that of the groove opening portion 13a is provided on the groove bottom portion 13b side continuously from the tapered shape 15 of the throttle portion. The narrow space portion 16 has a straight groove shape with a groove width dimension w ₃ set to be constant from the tapered shape 15 side to the groove bottom portion 13b side.

On the other hand, the gasket 31 is formed in a substantially circular cross section by a rubber-like elastic body. Width of the gasket w _4, the groove width of the groove opening w ₅ i.e. narrowed portion smaller than the maximum groove width of 14, and the diaphragm portion 14 the groove width w ₃ of the minimum groove width dimension or narrow space 16 of the It is set larger.

  FIG. 1A shows a case where the clearance c between the two members 11 and 21 is relatively large, and thus the gasket 31 is placed in a low compression state. In this low compression state, the gasket 31 is pressed against the tapered shape 15 of the throttle portion 14 by the assembly load of the two members 11 and 21. Therefore, since the gasket 31 is pressed against the tapered shape 15 of the throttle portion in this way, a seal surface pressure is generated, so that the gasket 31 and the one member 11 are sealed, and a good sealing property is secured.

  FIG. 1B shows a case where the clearance between the two members 11 and 21 is relatively small (in the drawing, it is almost zero), so that the gasket 31 is placed in a highly compressed state. In this high compression state, the assembly load of the two members 11 and 21 is increased, so that a part of the gasket 31 on the groove bottom portion 13 b side is pressed into the narrow space portion 16. Therefore, since a part of the gasket 31 is press-fitted into the narrow space portion 16 in this manner, the gasket repulsive force is reduced, so that the repulsive force does not become too large, and thus good sealing performance is maintained.

  The gasket 31 has a substantially circular cross section and is pressed so as to be seated on the tapered shape 15 of the narrowed portion 14 on both sides in the width direction in a low compression state (FIG. 1A). In the state of)), a part thereof is press-fitted into the narrow space portion 16, so that it does not fall down in the mounting groove 13.

  Further, as described above, a part of the gasket 31 is press-fitted into the narrow space portion 16 in a highly compressed state, so that the filling rate of the gasket 31 with respect to the mounting groove 13 does not become excessive.

  The mounting groove 13 and the gasket 31 may have the following configurations.

Second embodiment ...
In the example shown in FIG. 2, the width dimension w ₄ of the gasket 31 is set larger than the groove width dimension w ₅ of the groove opening, that is, the maximum groove width dimension of the throttle section 14, and then the minimum groove width dimension of the throttle section 14, It is set larger than the groove width dimension w ₃ of the narrow space portion 16. Further, the cross-sectional shape of the gasket 31 is a perfect cross-sectional shape.

Third embodiment ...
In the example illustrated in FIG. 3, the width dimension w ₄ of the gasket 31 is set to be equal to the groove width dimension w ₅ of the groove opening, that is, the maximum groove width dimension of the throttle section 14, and then the minimum groove width dimension of the throttle section 14. That is, it is set larger than the groove width dimension w ₃ of the narrow space portion 16. The cross-sectional shape of the gasket 31 is a polygonal cross-sectional shape (hexagonal shape) in which a pedestal portion 32 having a rectangular cross section on one member 11 side and a lip-shaped portion 33 having a trapezoidal cross section on the other member 21 side are combined. ing.

Fourth embodiment ...
In the example illustrated in FIG. 4, the width dimension w ₄ of the gasket 31 is set to be equal to the groove width dimension w ₅ of the groove opening, that is, the maximum groove width dimension of the throttle section 14, and then the minimum groove width dimension of the throttle section 14. It is set to be larger than w _3. The cross-sectional shape of the gasket 31 is a polygonal cross-sectional shape (hexagonal shape) in which a pedestal portion 32 having a rectangular cross section on one member 11 side and a lip-shaped portion 33 having a trapezoidal cross section on the other member 21 side are combined. ing. The groove width w ₆ of the groove bottom portion 13b is set smaller than than the minimum groove width w ₃ of the throttle section 14, thereby over the narrow space 16 is squeezed portion 14 side to the groove bottom portion 13b side groove width The taper is set so that the dimension gradually decreases.

  In each of the above embodiments, the same operational effects as those of the first embodiment can be exhibited.

DESCRIPTION OF SYMBOLS 1 Sealing device 11 One member 12,22 Opposite surface 13 Mounting groove 13a Groove opening part 13b Groove bottom part 13c Groove side part 14 Throttle part 15 Tapered shape 16 Narrow space part 21 Other member 31 Gasket 32 Base part 33 Lip shape Part

Claims (3)

A sealing device that seals between the two members by bringing a gasket mounted in a mounting groove provided in one of the two members facing each other into close contact with the other member,
Providing a narrowed portion having a tapered shape on the groove side surface on the inner surface of the mounting groove and providing a narrow space on the groove bottom side of the narrowed portion;
The width dimension of the gasket is set larger than the minimum groove width dimension of the throttle part,
The gasket is mounted when the gasket has a large clearance between the two members and the gasket is placed in a low compression state, and when the gasket has a small clearance between the two members and the gasket is placed in a high compression state. Set to a different state,
When the clearance between the two members is large and the gasket is placed in a low-compression state, the gasket is pressed against the tapered shape of the throttle portion by the assembly load of the two members, thereby generating a seal surface pressure. The gasket is not press-fitted into the narrow space part,
When the gasket is placed in a highly compressed state with a small clearance between the two members, a part of the gasket is press-fitted into the narrow space portion. The sealing device according to claim 1.
The sealing device according to claim 1, wherein the narrow space portion is set to have a constant groove width dimension from the narrowed portion side to the groove bottom side. The sealing device according to claim 1.
The narrow space portion has a groove width dimension set gradually smaller from the throttle portion side to the groove bottom portion side.

Images