JP5692504B2 - gasket - Google Patents

Description

  The present invention relates to a gasket which is a kind of sealing device. The gasket of the present invention is used, for example, in the field of automobiles or in the field of general industrial machinery.

  As shown in FIG. 3, a gasket used for a hydraulic path and sealed by receiving internal pressure generally has seal beads 15 and 16 at both axial ends of a gasket body 12 in which a reinforcing ring 14 is embedded. When the is mounted in the mounting groove 23, both the seal beads 15 and 16 fall into the inside (inward in the radial direction) (a structure that self-seals by receiving internal pressure). Both seal beads 15 and 16 receive pressure and apply a reaction force in the axial direction to the gasket body 12. When the pressure is high, the axial set of the gasket body 12 is caused by a small difference in rigidity between the beads 15 and 16. The position may behave to be shifted in one axial direction. In that case, there is a problem that the bead 16 on the side that loses the tightening margin loses pressure and the oil blows through, or the gap increases and the deformation region of the rubber increases, so that the distortion of the rubber increases and the durability crack occurs. .

Japanese Utility Model Publication No. 6-32834 JP-A-1-261564

  In view of the above, the present invention provides a gasket in which seal beads are provided at both axial ends of a gasket body in which a reinforcing ring is embedded, and when the hydraulic pressure acts on the gasket, the gasket body is axially moved in the mounting groove. It is an object of the present invention to provide a gasket capable of maintaining the sealing performance on the side where the tightening margin is lowered even when displaced to one side.

In order to achieve the above object, a gasket according to claim 1 of the present invention is a gasket that is mounted in a gasket mounting groove provided inside a housing having a hydraulic path and seals the hydraulic pressure, and has a reinforcing ring embedded therein. A gasket body, a first seal bead that is provided at one end of the gasket body in the axial direction and in close contact with one side surface of the mounting groove at the time of mounting; and provided at the other end in the axial direction of the gasket body A second seal bead that is in close contact with the other side surface of the mounting groove during mounting, and the first seal bead includes an end surface protruding portion that protrudes in one axial direction from one end surface of the gasket body, and the end surface The projecting portion includes a tapered surface on the radially outer side of the end surface and a plane perpendicular to the axis on the radially inner side, the first seal bead of the first seal bead 0 ° <α <β <90 °, where α is the bead angle, w1 is the bead width of the first seal bead, β is the bead angle of the second seal bead, and w2 is the bead width of the second seal bead. When w1 <w2, the gasket main body has a structure that is displaced in one axial direction in the mounting groove when the hydraulic pressure acts on the gasket, and the gasket main body is displaced in one axial direction. A third seal bead is provided along with the second seal bead to compensate for a decrease in sealing performance due to a decrease in the tightening allowance of the second seal bead.

  According to a second aspect of the present invention, in the gasket according to the first aspect, the first and second seal beads are radially inward where the hydraulic pressure exists when each of the first and second seal beads is mounted in the mounting groove. In contrast to this, the third seal bead is configured to fall radially outward and to be in close contact with both the other side surface and the bottom surface of the mounting groove.

  In the gasket of the present invention having the above-described configuration, a third seal bead is provided along with the second seal bead to compensate for a decrease in sealing performance due to a decrease in tightening allowance of the second seal bead due to the axial displacement of the gasket body. For this reason, it is possible to compensate for the decrease or deficiency in the sealing performance due to the second seal bead by the newly provided third seal bead.

  The phenomenon in which the gasket body is displaced in one axial direction within the mounting groove when hydraulic pressure acts on the gasket is likely to occur in the following manner.

(1) First aspect
As shown in FIG. 4A, the first seal bead 15 on one axial side (upper in the figure) and the second seal bead 16 on the other axial side (lower in the figure) are asymmetric in the axial direction (vertical direction in the figure). And the second seal bead 16 is set to have a higher rigidity than the first seal bead 15.
In this case, (indicating the displacement direction by the arrow H) 4 gasket body 12 when the hydraulic pressure P ₁ of the high pressure acts on the gasket 11, as shown in (B) is easily displaced in the axial direction while in the mounting groove 23, Further, the displacement easily (displacement direction in the axial direction while the gasket body 12 in the mounting groove 23 when the gasket 11 is strongly compressed P ₂ in the axial direction as shown in FIG. 4 (C) by an arrow H Show).

(2) Second aspect ...
As shown in FIG. 5A, the reinforcing ring 14 is disposed in the gasket body 12 so as to be offset in one axial direction.
In this case, (indicating the displacement direction by the arrow H) 5 the gasket body 12 when the hydraulic pressure P ₁ of the high pressure acts on the gasket 11, as shown in (B) is easily displaced in the axial direction while in the mounting groove 23. In this case, the unlike the first embodiment, FIG. 5 the gasket body 12 when the gasket 11 as shown in (C) is strongly compressed P ₂ axially displaced in the axial direction while in the mounting groove 23 Never do.

(3) Third aspect
As shown in FIG. 6A, the first seal bead 15 on one axial side (upper in the figure) and the second seal bead 16 on the other axial side (lower in the figure) are asymmetric in the axial direction (vertical direction in the figure). And the second seal bead 16 is set to have a higher rigidity than the first seal bead 15 and the reinforcing ring 14 is disposed in the gasket body 12 so as to be offset in the axial direction.
In this case, (indicating the displacement direction by the arrow H) when the hydraulic pressure P ₁ of the high pressure is exerted on the gasket 11 gasket body 12 is displaced easily to one axial direction within the mounting groove 23 as shown in FIG. 6 (B), Further, the displacement easy (displacement direction axially one gasket body 12 in the mounting groove 23 when the gasket 11 is strongly compressed P ₂ axially as shown in FIG. 6 (C) by an arrow H Show).

  Therefore, in the above aspects (1) to (3), when the gasket body 12 in which the reinforcing ring 14 is embedded is displaced in the axial direction in the mounting groove 23, the tightening margin on the side surface of the mounting groove 23 of the second seal bead 16 is increased. As a result, the sealing performance by the second seal bead 16 may decrease.

Therefore, in the present invention, as corresponding to the first and third aspects, a third seal bead is provided at the other end in the axial direction of the gasket body along with the second seal bead. Similar to the second seal bead, it is brought into close contact with the side surface of the mounting groove, whereby the third seal bead compensates for the decrease or deficiency of the sealing performance due to the second seal bead.

  The third seal bead is in close contact with the side surface of the mounting groove as described above, but may be in close contact with the bottom surface of the mounting groove at the same time. In this case, further improvement in sealing performance can be expected. It becomes possible.

  The present invention has the following effects.

That is, in the gasket of the present invention, as described above, the gasket is formed by providing seal beads at both axial ends of the gasket body in which the reinforcing ring is embedded, and the bead angle of the first seal bead is α, and the bead width is When w1 and the bead angle of the second seal bead is β and the bead width is w2, the bead angle 0 ° <α <β <90 ° and the width w1 <w2, so that the hydraulic pressure acts on the gasket. When the gasket body has a structure in which the gasket body is displaced in one axial direction within the mounting groove, even when the gasket body is displaced in one axial direction in the mounting groove when hydraulic pressure acts on the gasket, Since the sealing performance on the side where the tightening margin decreases is compensated by the third sealing bead, the sealing performance of the gasket as a whole is maintained and improved. Door can be. Further, when the third seal bead is brought into close contact with both the side surface and the bottom surface of the mounting groove, further improvement in sealing performance can be expected.

Half sectional view of a gasket according to an embodiment of the present invention Half cut section when mounting the gasket on different housing structures Half cut sectional view of the gasket according to the conventional example Explanatory drawing of the 1st aspect which shows the phenomenon which a gasket main body displaces to an axial direction one side within a mounting groove. Explanatory drawing of the 2nd aspect which shows the phenomenon which a gasket main body displaces to an axial direction one side in a mounting groove. Explanatory drawing of the 3rd aspect which shows the phenomenon which a gasket main body displaces to an axial direction one side within a mounting groove.

The present invention includes the following embodiments.
(A)
As shown in FIG. 1, the bead angle of the first bead 15 is α, the bead width is w1, the bead angle of the second bead 16 is β, the bead width is w2, and the bead angle 0 ° <α <β <90. By setting the angle and the width w1 <w2, the position of the gasket 11 when subjected to the internal pressure can be brought to the upper surface side stably. Further, the third bead 17 is provided on the outer peripheral side so that the second bead 16 is not distorted due to internal pressure. Due to the presence of the third bead 17 in the second bead 16, the amount of deformation can be suppressed and stable sealing performance can be exhibited. On the other hand, when the second bead 16 receives the internal pressure and is pushed to the outer peripheral side, the third bead 17 is tightened with the inner diameter surface of the housing 21 and exhibits a sealing function. The third bead 17 has a tapered portion 17e that is deformed so as to spread toward the outer peripheral side when the gasket 11 is crushed up and down. Moreover, as shown in FIG. 2, the insertion direction of the gasket 11 is eliminated by digging the grooves 23 above and below the mating housings 21a and 21b.

(B)
Instead of setting the bead angle 0 ° <α <β <90 ° and the width w1 <w2, the position of the reinforcing ring 14 is made axially asymmetric (one end surface of the reinforcing ring 14). There is a deformable body (rubber 13) only on the other end face in the axial direction, or the axial thickness of the rubber 13 existing on one end face (the other end face in the axial direction) of the reinforcing ring 14 is the opposite end face (one in the axial direction). The thickness of the second bead 16 is larger than the axial thickness of the rubber 13 existing on the end face of the first bead) and the bead rigidity (bead wall thickness) is different (the rigidity of the second bead 16 is larger than the rigidity of the first bead 15). ), Or the bead rigidity with rubber on one end face of the ring may be increased (the rigidity of the bead 16 with rubber 13 on one end face of the reinforcing ring 14 may be increased).

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

  FIG. 1 shows a half cut section of a gasket 11 according to an embodiment of the present invention. The gasket 11 according to this embodiment is mounted in a gasket mounting groove 23 provided inside a housing 21 having a hydraulic path 22, such as a joint seal in an automatic transmission (AT) in a vehicle such as an automobile, and seals the hydraulic pressure. However, it is configured as follows.

  That is, a gasket main body 12 in the gasket 11 is provided by embedding a reinforcing ring 14 made of a rigid material such as a metal inside an annular body (rubber annular body) 13 made of a predetermined rubber-like elastic body. A first seal bead 15 that is in close contact with one side surface 23a of the mounting groove 23 at the time of mounting is integrally formed with the rubber-like elastic body at one end (upper in the drawing) of the gasket body 12 in the axial direction. A second seal bead 16 that is in close contact with the other side surface 23b of the mounting groove 23 at the time of mounting is integrally formed with the rubber-like elastic body at the other end in the axial direction of 12 (lower in the figure). The mounting groove 23 has a rectangular cross section and opens inward in the radial direction. The axial width of the gasket body 12 is set slightly smaller than the axial width of the mounting groove 23. The outer diameter dimension of the gasket body 12 is set slightly smaller than the diameter dimension of the bottom surface 23 c of the mounting groove 23.

  The first and second seal beads 15 and 16 are configured to fall inward in the radial direction by tightening when they are in close contact with the side surfaces 23a and 23b of the mounting groove 23 during mounting.

  Therefore, the first seal bead 15 is formed so as to protrude diagonally inward in the radial direction from the gasket main body 12 as a whole, and thereby protrude by a predetermined width inward in the radial direction from the inner diameter surface 12a of the gasket main body 12. And an end surface protrusion 15b that protrudes a predetermined width in the axial direction from one end surface 12b of the gasket body 12. In the figure, the radial protruding width of the inner diameter protruding portion 15a is indicated by w1. The former inner diameter protruding portion 15a includes a tapered surface 15c on the bead base end side (the other side in the axial direction) on the inner diameter surface, and a cylindrical surface 15d on the bead distal end side (one axial direction side). The inclination of the tapered surface 15c is such that the bead inner diameter dimension gradually decreases from the other axial direction to the other axial direction. In the figure, the inclination angle of the tapered surface 15c is indicated by α. The latter end surface protrusion 15b includes a tapered surface 15e on the bead base end side (radially outward side) of the end surface, and an axially perpendicular plane 15f on the bead distal end side (radially inward side). The taper surface 15e is inclined such that the bead outer diameter gradually decreases from the other axial direction to the other axial direction.

  On the other hand, the second seal bead 16 as a whole is formed so as to protrude diagonally inward in the radial direction from the gasket main body 12, and thereby has a predetermined width inward in the radial direction from the inner diameter surface 12 a of the gasket main body 12. A protruding inner diameter protruding portion 16a and an end surface protruding portion 16b protruding a predetermined width in the other axial direction than the other end surface 12c of the gasket body 12 are provided. In the figure, the radial protruding width of the inner diameter protruding portion 16a is indicated by w2. The former inner diameter protruding portion 16a includes a tapered surface 16c on the bead base end side (one axial direction side) on the inner diameter surface and a cylindrical surface 16d on the bead distal end side (the other axial direction side). The inclination of the tapered surface 16c is such that the bead inner diameter dimension gradually decreases from one axial direction to the other axial direction. In the figure, the inclination angle of the tapered surface 16c is indicated by β. The latter end surface protrusion 16b includes a tapered surface 16e on the bead base end side (radially outward side) of the end surface, and an axially perpendicular plane 16f on the bead distal end side (radially inward side). The inclination of the tapered surface 16e is such that the bead outer diameter dimension gradually decreases from one axial direction to the other axial direction.

  In the first and second seal beads 15, 16 configured as described above, the inclination angle β of the tapered surface 16 c of the inner diameter protruding portion 16 a of the second seal bead 16 is set to be equal to that of the tapered surface 15 c of the inner diameter protruding portion 15 a of the first seal bead 15. The inclination angle α is set to be larger (0 ° <α <β <90 °), and the radial protrusion width w2 of the inner diameter protrusion 16a in the second seal bead 16 is the diameter of the inner diameter protrusion 15a in the first seal bead 15. It is set to be larger than the direction protrusion width w1 (w1 <w2). Accordingly, both the seal beads 15 and 16 have a cross-sectional shape that is asymmetric in the axial direction (vertical direction in the drawing), and the second seal bead 16 has higher rigidity than the first seal bead 15 and is less likely to be crushed in the axial direction. This corresponds to the “(1) first mode” described above, and corresponds to the first half of the “(3) third mode”.

  Further, in the gasket main body 12 having the above-described configuration, the reinforcing ring 14 is arranged so as to be offset in the axial direction in the gasket main body 12 as shown in the figure, and this is the same as the above-mentioned “(2) Second mode”. This corresponds to the latter half of “(3) Third mode”.

  Accordingly, the gasket 11 having the above-described configuration corresponds to the above-described “(1) first mode”, “(2) second mode”, and “(3) third mode”. When a high pressure oil pressure is applied from the inside in the direction, the gasket body 12 is easily displaced in one axial direction in the mounting groove 23. When the gasket body 12 is displaced in one axial direction in the mounting groove 23 in this way, the mounting groove 23 is disposed. The tightening allowance of the second seal bead 16 with respect to the other side surface 23b of the second seal bead may decrease, and the sealing performance by the second seal bead 16 may thereby decrease.

  Therefore, in order to prevent this, in the gasket 11, a third seal bead 17 is provided alongside the second seal bead 16 on the outer diameter side, and the third seal bead 17 is the same as the second seal bead 16. The third seal bead 17 is configured to compensate for a decrease or deficiency in the sealing performance due to the second seal bead 16 by being in close contact with the other side surface 23b of the mounting groove 23.

  The third seal bead 17 is formed so as to protrude diagonally outward in the radial direction from the gasket body 12 as a whole, and thereby, the outer surface protrudes radially outward from the outer diameter surface 12d of the gasket body 12 by a predetermined width. A diameter projecting portion 17a and an end surface projecting portion 17b projecting a predetermined width in the axial direction from the other end surface 12c of the gasket body 12 are provided. The former outer diameter protrusion 17a includes a tapered surface 17c on the bead base end side (one axial direction side) on the outer diameter surface, and a cylindrical surface 17d on the bead distal end side (the other axial direction side). The taper surface 17c is inclined such that the bead outer diameter dimension gradually increases from one axial direction to the other axial direction. The latter end face protrusion 17b has a tapered surface 17e on the bead base end side (radially inward side) of the end face, and an axially perpendicular plane 17f on the bead distal end side (radially outward side). The taper surface 17e is inclined such that the bead inner diameter dimension gradually increases from one axial direction to the other axial direction.

  The third seal bead 17 is in close contact with the other side surface 23b of the mounting groove 23 at the time of mounting, and at this time, the third sealing bead 17 is configured to be tilted outward in the radial direction by tightening allowance. At the same time, it also comes into close contact with the bottom 23c of the mounting groove 23 at the same time. Therefore, it is possible to exhibit excellent sealing performance.

  As described above, in the gasket 11 according to this embodiment, in the gasket 11 in which the seal beads 15 and 16 are provided at both axial ends of the gasket body 12 in which the reinforcing ring 14 is embedded, the hydraulic pressure acts on the gasket 11. Even when the gasket body 12 is sometimes displaced in the axial direction in the mounting groove 23, the third seal bead 17 compensates for the sealing performance on the side where the tightening margin is reduced. It is possible to maintain and improve the sealing performance. Further, since the third seal bead 17 is structured to be in close contact with both the side surface 23b and the bottom surface 23c of the mounting groove 23, further improvement in sealing performance can be expected.

  In the above embodiment, the inclination angle β of the inner diameter tapered surface 16c of the second seal bead 16 is set larger than the inclination angle α of the inner diameter tapered surface 15c of the first seal bead 15 (0 ° <α <β <90 °). ) And the radial protruding width w2 of the second seal bead 16 is set to be larger than the radial protruding width w1 of the first seal bead 15 (w1 <w2), so that the second seal bead 16 becomes the first seal. Instead of this, the second seal bead 16 is thicker than the first seal bead 15 so that the second seal The bead 16 may have a shape that is more rigid and less likely to be crushed than the first seal bead 15.

  Moreover, in the said Example, since the housing 21 is a structure divided into two axial directions by the one axial direction edge part in the bottom face 23c of the mounting groove 23, there exists a possibility that there may be restrictions regarding the mounting direction of the gasket 11. FIG. is there. That is, in the above embodiment, the housing 21 is divided into two in the axial direction at one end in the axial direction on the bottom surface 23c of the mounting groove 23 by a combination of the half halves 21a and 21b, as shown in FIG. Since the third seal bead 17 is disposed at the other end in the axial direction on the bottom surface 23c of the mounting groove 23, the third seal bead 17 does not protrude into the gap portion 21c formed by dividing the housing into two. However, if the gasket 11 is to be mounted in the opposite direction in the axial direction, the third seal bead 17 may protrude from the gap portion 21c formed by splitting the two housings, and thus may be damaged. Can not be attached to. Therefore, in order to cope with this, as shown in FIG. 2, the housing 21 may be divided into two in the axial direction at the central portion in the axial direction on the bottom surface 23c of the mounting groove 23. Even if the gasket 11 is mounted in any direction, the problem of the protrusion can be solved in advance. The configuration of the gasket 11 in FIG. 2 is exactly the same as the configuration of the gasket 11 in FIG.

  Furthermore, in the above embodiment, the shape of the reinforcing ring 14 is the simplest cylindrical shape, but the shape of the reinforcing ring 14 is not particularly limited. For example, a radial flange is integrally provided at the end of the cylinder. It may be a thing.

DESCRIPTION OF SYMBOLS 11 Gasket 12 Gasket body 12a Inner diameter surface 12b, 12c End surface 12d Outer diameter surface 13 Rubber annular body 14 Reinforcement ring 15 1st seal bead 15a, 16a Inner diameter protrusion part 15b, 16b, 17b End surface protrusion part 15c, 15e, 16c, 16e, 17c, 17e Tapered surfaces 15d, 16d, 17d Cylindrical surfaces 15f, 16f, 17f Axis perpendicular to the axis 16 Second seal bead 17 Third seal bead 17a Outer diameter protruding portion 21 Housing 21c Clearance portion 22 Hydraulic path 23 Mounting groove 23a, 23b Side surface 23c Bottom

Claims (2)

A gasket that is mounted in a gasket mounting groove provided inside a housing having a hydraulic path and seals the hydraulic pressure,
A gasket body in which a reinforcing ring is embedded; a first seal bead that is provided at one end of the gasket body in the axial direction and is in close contact with one side surface of the mounting groove during mounting; and the other end in the axial direction of the gasket body A second seal bead that is provided at the portion and is in close contact with the other side surface of the mounting groove when mounted,
The first seal bead includes an end surface protruding portion that protrudes in one axial direction from one end surface of the gasket body, and the end surface protruding portion includes a tapered surface on a radially outward side of the end surface and is radially inward. With a plane perpendicular to the axis on the side,
The bead angle of the first seal bead is α, the bead width of the first seal bead is w1, the bead angle of the second seal bead is β, and the bead width of the second seal bead is w2.
0 ° <α <β <90 ° and
When w1 <w2, the gasket main body has a structure that is displaced in one axial direction within the mounting groove when the hydraulic pressure acts on the gasket.
A third seal bead is provided alongside the second seal bead to compensate for a decrease in sealing performance due to a decrease in tightening allowance of the second seal bead accompanying a displacement of the gasket body in one axial direction. gasket. The gasket according to claim 1,
Each of the first and second seal beads is configured to collapse radially inward where the hydraulic pressure exists when mounted in the mounting groove, whereas the third seal bead collapses radially outward to A gasket characterized by being in close contact with both the other side surface and the bottom surface of the mounting groove.

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