JP7449563B2 - gasket - Google Patents

Description

The present invention relates to a gasket that is attached to a groove formed in one member in order to seal between two members.

Among the above-mentioned gaskets, gaskets that seal between one member having a flat surface and an arc-shaped surface continuous thereto and the other member formed to match the shape of the one member are flat. It is difficult to seal the corner surface where the shaped surface and the arc-shaped surface intersect, and the resulting gap is filled with a liquid gasket.
Therefore, in order to improve the sealing performance, Patent Document 1 listed below discloses a gasket that includes a thick protrusion that protrudes in the groove width direction at a portion that seals a corner surface.

Japanese Patent Application Publication No. 2003-21237

However, in the case of the gasket disclosed in Patent Document 1, when one member is combined with the other member, the protrusion has too much volume, and the protrusion comes into elastic contact with the arcuate surface of the other member, causing curling or displacement. If it is assembled in this condition, a gap will occur and the sealing performance as designed will not be achieved. Furthermore, if one member and the other member are made of resin or the like and have low rigidity, the protrusions may cause overfilling, which may cause deformation of the resin member.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a gasket that can achieve sealing performance as properly designed and is easy to assemble.

The gasket according to the present invention includes one member having a flat surface and an arc-shaped surface formed continuously thereon, and a flat surface joined to the flat surface of the one member and the arc-shaped surface formed continuously thereon. A gasket made of an elastic material that has a circular arc-shaped surface and a circular arc-shaped surface that merges with the one member and seals between the one member and the other member that faces and joins, the gasket being fitted into a groove formed in the one member. The gasket body includes a gasket body that is attached to the gasket body, and a collar part that is formed to protrude in the groove width direction from both sides of the gasket body, and the gasket body has a flat part that is formed along the flat face. , the arc-shaped part is formed along the arc-shaped surface, and the corner part where the flat part and the arc-shaped part intersect, and the arc-shaped part is formed along the arc-shaped surface of the other member. The opposing surface has a tapered portion that slopes toward the flat portion, and the corner portion has a protruding portion formed to protrude from the flat portion toward the flat surface of the other member. It is characterized by

According to the gasket of the present invention, since the arcuate portion of the gasket has a tapered portion, the tapered portion elastically contacts the corner surface where the flat surface and the arcuate surface on the other member side, which are difficult to seal, intersect. It is possible to achieve sealing performance as per the appropriate design. Furthermore, since the protruding portion is formed to protrude from the flat portion toward the flat surface of the other member, sealing can be achieved without creating a gap between the corner surfaces of the other member.

According to the gasket according to the present invention, it is possible to realize sealing performance as properly designed, and it is possible to make it easy to assemble.

FIG. 1 is a schematic front view schematically showing main parts of a gasket according to an embodiment of the present invention. 2 is a partially enlarged view for explaining the structure around the corner of the same gasket, and is an enlarged view of the X section in FIG. 1. FIG. (a) and (b) are partially enlarged views for explaining the structure around the corner of the same gasket, where (a) is a schematic perspective view seen from the direction of arrow A in FIG. 2, and (b) is a diagram 2 is a schematic perspective view seen from the direction of arrow B in FIG. (a) is a sectional view taken along the YY line in FIG. 2, and (b) is a schematic sectional view of the gasket fitted into the groove of the head cover. (a) is a cross-sectional perspective view taken along the ZZ line in FIG. 2, and (b) is a schematic perspective view when FIG. 2 is viewed from above. (a) and (b) are schematic front views schematically showing a state in which the gasket is attached to a head cover of a cylinder head. (a) is a diagram for explaining the state before the head cover is combined with the cylinder head, and (b) is a diagram for explaining the state after the head cover is combined with the cylinder head.

Embodiments of the present invention will be described below.
The gasket according to this embodiment seals between one member and the other member, and is fitted into a groove formed in the one member. One member has a flat surface and an arcuate surface continuous with the flat surface. The other member has a flat surface that merges with the flat surface of the one member, and an arcuate surface that is formed continuously therewith and merges with the arcuate surface of the one member. The gasket includes a gasket body that is fitted into a groove formed in one member, and a flange formed to protrude in the groove width direction from both sides of the gasket body. The gasket body includes a flat portion formed along the flat surfaces of the one member and the other member, an arcuate portion formed along the arcuate surfaces of the one member and the other member, and the flat portion. and a corner where the arcuate portion intersects, and the arcuate portion has a tapered portion where a surface facing the arcuate surface of the other member slopes toward the flat portion. . The corner portion has a protrusion formed to protrude from the flat portion toward the flat surface of the other member.
A detailed description will be given below with reference to the drawings. Note that some of the detailed symbols attached to other figures are omitted from some of the figures.

1 to 6 show an example of a gasket according to this embodiment.
The gasket 1 in this embodiment is suitably used as a gasket for sealing between two members, one member having a semicircular arch portion and the other member. Therefore, the one member and the other member may be, for example, two opposing members of the head cover, cylinder head, cylinder block, oil pan, and chain cover that constitute an automobile engine, or may be two other members. It's okay.
An example in which the gasket 1 of this embodiment is applied to a head cover gasket installed between a cylinder head 3 (the other member) and a head cover 2 (the one member) of an engine mounted in an automobile will be described below. The head cover 2 is made of a molded product of resin or the like, and is provided so as to cover and cover the upper surface of the cylinder head 3. The peripheral edge of the head cover 2 is formed with a flange portion 2a that protrudes outward in a brim shape, and a bolt is inserted into the flange portion 2a to be fastened and integrated with the peripheral edge of the cylinder head 3. A hole (not shown) is provided. The shape and size of the arch portion 30 of the cylinder head 3 are designed to connect a camshaft (not shown) installed horizontally in the cylinder head 3 to a drive transmission member installed outside the cylinder head 3. Formed according to shape and size.

As shown in FIG. 1, the flange portion 2a of the head cover 2 has a flat surface 21, an arcuate surface 22 formed continuously with the flat surface 21, and an intersection between the flat surface 21 and the arcuate surface 22. It has a corner surface (pin angle) 23. The arc-shaped surface 22 is formed to merge with the arc-shaped surface 32 of the arch portion 30 of the cylinder head 3. Specifically, the arc-shaped surface 22 is formed in a curved shape whose central portion is convex upward in accordance with the shape and size of the arch portion 30, that is, in the shape of a semicircular arch. Flat shaped surfaces 21, 21 are formed. Further, in the flange portion 2a of the head cover 2, a concave groove 20 into which the gasket 1 is fitted is formed in an annular shape in the circumferential direction. The illustrated groove 20 has an opening 20c that is open at the bottom, side walls 20a, 20a, a bottom 20b, and a wall corner 20d (see FIG. 4(b)). The depth dimension and shape of the groove 20 are formed to match the shape of the gasket 1. In the groove 20 in this embodiment, as shown in FIG. 4(b), the flanges 100, 100 of the gasket 1 The gasket body 10 is provided so as to protrude from the opening 20c, and most of the gasket body 10 is accommodated within the groove 20.

A peripheral portion of the cylinder head 3 that joins the flange portion 2a of the head cover 2 has a flat surface 31 and an arcuate surface 32 formed continuously with the flat surface 31. Similar to the arc-shaped surface 22 of the head cover 2, the arc-shaped surface 32 formed on the cylinder head 3 also has a curved shape whose central portion is convex upward in accordance with the shape and size of the arch portion 30, that is, a semicircle. It is formed in an arch shape, and flat surfaces 31, 31 are formed on both sides of the arc-shaped surface 32.

Since the head cover 2 and the cylinder head 3 are joined facing each other and combined, the flat surface 21 of the head cover 2 is formed corresponding to the flat surface 31 of the cylinder head 3, and the flat surface 21 of the head cover 2 is formed to correspond to the flat surface 31 of the cylinder head 3. A circular arc-shaped surface 22 of the head cover 2 is formed correspondingly. A gasket 1 is provided to seal the combined surface of the head cover 2 and cylinder head 3. Therefore, when the head cover 2 is fastened to the cylinder head 3 with bolts, the flat surfaces 21 and 31, which are the surfaces to be sealed, are sealed together due to the elastic deformation of the gasket 1 due to the compression caused by tightening (see FIG. 4(b)). ), the arc-shaped surfaces 22 and 32 are also sealed together.

The gasket 1 includes a gasket body 10 that is fitted into a groove 20 and mounted thereon, and flanges 100, 100 that are formed to protrude from both sides of the gasket body 10 in the groove width direction. The gasket body 10 is formed in a vertically elongated rectangular shape when viewed in cross section, and the flange portion 100 is formed on the lower side of the gasket body 10 (on the rear side in the direction of insertion into the groove 20). When the gasket 1 is installed in the groove 20, the flanges 100, 100 are exposed in the groove width direction, as shown in FIG. 4(b), FIG. 6(a), etc.
As shown in FIG. 1, etc., the gasket body 10 and the flanges 100, 100 are integrally molded products, and are made of elastic material such as rubber, mainly NBR, H-NBR, ACM, AEM, FKM, etc. It is formed using materials. The gasket body 10 and the flange portion 100 each have flat portions 11, 111, arcuate portions 12, 112, and corner portions 13, 113.
Specifically, the gasket body 10 includes a flat portion 11 formed along a flat surface 21 of the flange portion 2a, an arcuate portion 12 formed along an arcuate surface 22 of the flange portion 2a, It has a corner 13 where the flat portion 11 and the arcuate portion 12 intersect. The flange portion 100 also includes a flat portion 111 formed along the flat surface 21 of the flange portion 2a, an arc portion 112 formed along the arc surface 22 of the flange portion 2a, and a flat portion 111 formed along the arc surface 22 of the flange portion 2a. and a corner portion 113 where the arc-shaped portion 112 intersects.

Further, the gasket 1 has rod-shaped protrusions 14 formed at appropriate intervals in the insertion direction into the groove 20 on both side surfaces 10a, 10a. The protrusion 14 includes one in which a fall prevention protrusion 14a is formed, and another in which a fall prevention protrusion 14b having a larger diameter than the fall prevention protrusion 14a is formed in addition to the fall prevention protrusion 14a. The protrusion 14 is appropriately formed in the height direction of the side surface 10a of the gasket body 10, and the fall prevention protrusion 14a prevents the gasket body 10 from falling or meandering within the groove 20. Further, the falling-off prevention protrusion 14b prevents the gasket 1 fitted into the groove 20 from falling off from the groove 20 when the head cover 2 is assembled to the cylinder head 3.

The arcuate portion 12 of the gasket body 10 has tapered portions 12a, 12a in its lower portions on both sides, the surfaces facing the arcuate surface 32 of the cylinder head 3 being inclined toward the flat portions 11, 11. There is.
As shown in FIG. 1, the angle α at which the perpendicular L passing through the center of the arc-shaped portion 12 of the gasket body 10 intersects with the line L1 passing through the lower part (corner 13 side) of the arc-shaped portion 12 is 15°. , the tapered portion 12a is formed to be inclined along the line L1. Although FIG. 1 shows an example in which the angle α is 15°, it is preferable to set the angle α to 10° to 20° because the effects described below will be achieved.

According to the gasket 1 of this embodiment, the arcuate portion 12 has the above-mentioned taper portion 12a, so the corner surface where the flat surface 31 and the arcuate surface 32 on the cylinder head 3 side, which are difficult to seal, intersect. The tapered portion 12a is in moderately close and elastic contact with 33, and sealing performance as properly designed can be achieved. That is, if the arc-shaped portion 12 of the gasket 1 is formed along the arc-shaped surface 32 of the cylinder head 3, when the head cover 2 is assembled to the cylinder head 3, the corner portion 13 of the gasket body 10 will be formed along the arc-shaped surface 32 of the cylinder head 3. However, according to the gasket 1 of this embodiment, since the arcuate portion 12 has the tapered portion 12a, it is possible to prevent the gasket from turning over, and the gasket is easy to assemble. It can be a gasket.
The degree of inclination of the tapered part 12a is set depending on the shape and size of the arch part, and the angle α can be set in a range of 5 to 30°. When the above-mentioned angle α of the tapered portion 12a is less than 5°, there is not much difference when the head cover 2 is assembled to the cylinder head 3 compared to when the tapered portion 12a is not provided (when the angle α is 0°). Therefore, the desired function of the tapered portion 12a cannot be achieved, and the flange portion 100 tends to curl up. On the other hand, if the angle α exceeds 30°, the gap formed between the arc-shaped surface 32 of the cylinder head 3 and the gasket 1 will be too large, and the sealing performance will tend to deteriorate.

The corner portion 13 of the gasket body 10 has a protruding portion 13 a formed to protrude from the flat portion 11 toward the flat surface 31 of the cylinder head 3 . As shown in the partially enlarged view of FIG. 2, FIGS. 3(a), 3(b), etc., the protruding portion 13a extends toward the flat surface 31 of the cylinder head 3 from the extension line of the flat portion 11. It is formed to gradually protrude (slope). The thickness of the flange 100 at the protrusion 13a (t1, see FIG. 4(a)) is smaller than the thickness of the flange 100 at the portion corresponding to the flat-shaped portion 11 (t2, see FIG. 5(a)). It is formed so that the thickness gradually increases toward the portion corresponding to the portion 13. Further, the lower surface 100b of the flange 100 in the protrusion 13a is formed to be inclined toward a portion corresponding to the corner 13, and accordingly, the flange 100 has a protruding portion 100c that protrudes in a substantially triangular shape when viewed from the front. (See Figure 2).

As described above, according to the present embodiment, since the protruding portion 13a is formed to protrude from the flat portion 11 toward the flat surface 31 of the cylinder head 3, it is possible to prevent the corner surface 33 of the cylinder head 3 from sealing easily. Proper sealing can be achieved without creating a gap between the gasket 1 and the gasket 1. Further, according to the present embodiment, the thickness of the flange portion 100 in the protrusion portion 13a is formed so that the thickness gradually increases from the portion corresponding to the flat-shaped portion 11 to the portion corresponding to the corner portion 13. The gasket 1 can be assembled along the flat surface 31, and the corner surface 33 where the surface pressure tends to decrease can be appropriately sealed.
In addition to sealing with the gasket 1 described above, it is desirable to apply a liquid gasket (FIPG (Formed in Place Gasket)) to, for example, the corner surface 33 (and its surroundings). In this case, even if there are vibrations, pressure fluctuations, etc., the degree of adhesion of the gasket 1 to the corner surface 33 (and its surroundings) can be reinforced and the sealing performance can be improved.

As shown in FIG. 2, the degree of downward protrusion (inclination) of the protruding portion 13a is set such that it comes into elastic contact with the corner surface 33 with an appropriate surface pressure, and the flange of the flat portion 11 of the gasket body 10 It is desirable that the angle β at which the extension line L2 of the lower surface 100b of the projection part 100 intersects with the line L3 corresponding to the lower surface 100b of the protrusion 13a is 5° to 20°. An example is shown below. Further, the lower surface 100b of the flange 100 in the protrusion 13a is formed to be inclined toward a portion corresponding to the corner 13 depending on the degree of protrusion of the protrusion 13a. Therefore, depending on the inclination angle of the lower surface 100b of the flange 100, the degree of protrusion of the flange protrusion 100c varies.
According to the gasket 1 of this embodiment, the surface pressure of the gasket 1 can be adjusted with a simple structure in which the protruding portion 13a is formed at an angle, and the corner surface 33, which is difficult to seal, can be more properly sealed. can be sealed. When the above-mentioned angle β is less than 5°, there is not much difference from the case where the protrusion 13a is not formed, and there is a tendency that the desired sealing performance cannot be achieved. On the other hand, when the angle β exceeds 20°, the surface pressure against the flat surface 31 of the cylinder head 3 becomes too high, and the sealing performance tends to deteriorate.

A built-up portion 15 that is thicker than other portions is formed between the corner portion 13 of the gasket body 10 and the flange portion 100 that is continuous with the corner portion 13. Specifically, as shown in FIG. 2 and FIG. 5(b), the built-up portion 15 is formed to be gently raised in a substantially triangular shape in a front view and a plan view, and the side on the flat-shaped portion 11 side is The length is longer than the length of the side on the arcuate portion 12 side. Therefore, when the tapered part 12a comes into elastic contact with the corner surface 33, the protrusion part 13a is filled in a part where a gap is likely to occur, and the built-up part 15 has the function of pressing the protrusion part 13a, so that the corner surface 33 Since there is no gap between the seals and a suitable surface pressure can be applied to the arcuate surfaces 32, angular surfaces 33, and flat surfaces 31 to be sealed, more appropriate sealing can be achieved.
The built-up portion 15 is formed so that the width dimension gradually increases toward the collar portion 100 in a cross-sectional view as shown in FIG. 4(a).
Therefore, according to the gasket 1 of the present embodiment, the gasket body 10 can be inserted smoothly into the groove 20 without getting stuck in the built-up portion 15 during installation, so that the insertability of the gasket body 10 into the groove 20 is improved. Get better.
The built-up portion 15 has a thickness such that it comes into elastic contact with the wall corner portions 20d, 20d on both sides forming the groove 20 when the gasket body 10 is attached to the groove 20.
Therefore, according to the gasket 1 of this embodiment, the ease of attachment to the groove 20 is improved, so that the gasket 1 can be prevented from falling off from the groove 20 of the head cover 2. Furthermore, when the head cover 2 is assembled to the cylinder head 3, the flange 100 corresponding to the corner 13 of the gasket body 10 has a function of holding down the curling, thereby further improving the ease of assembly.

Next, with reference to FIGS. 4 and 6, how to attach the gasket 1 to the groove 20 and how to seal between the head cover 2 and the cylinder head 3 will be further explained.
The gasket 1 is inserted into the other surface 10b of the gasket body 10 on the upper side (the front side in the direction of insertion into the groove 20) from the opening 20c of the groove 20 (see FIG. 4(a)). Then, the gasket body 10 is inserted until the other side 10b comes into elastic contact with the bottom 20b of the groove 20 and the gasket body 10 is elastically deformed (see FIG. 4(b)). At this time, both side surfaces 10a, 10a of the gasket body 10 partially came into elastic contact with the side walls 20a, 20a, and the fall prevention protrusion 14a and fall prevention projection 14b shown in FIG. 1 etc. came into elastic contact with the side walls 20a, 20a. state. As a result, the gasket body 10 can be smoothly assembled in an appropriate state without meandering within the groove 20 or falling off from the groove 20. Then, in this state, the head cover 2 is placed from above the cylinder head 3 so that the arc-shaped surface 22 and the arc-shaped surface 32 are combined, and the head cover 2 is joined to the cylinder head 3 (see FIG. 6(a)). reference). At this time, since the arcuate portion 12 of the gasket 1 has a tapered portion 12a, the tapered portion 12a is formed on the corner surface 33 where the flat surface 31 and the arcuate surface 32 on the side of the cylinder head 3, which is difficult to seal, intersect. The corners 13 of the gasket 1 will not contact the arc-shaped surface 32 of the cylinder head 3 and be rolled up. Next, while aligning the tapered portion 12a along the arcuate surface 32, the gasket 1 is joined to a position where the flat portion 11 of the gasket 1 comes into elastic contact with the flat surface 31 of the cylinder head 3 (see FIG. 6(b)). At this time, since the protrusion 13a is formed on the corner 13 of the gasket 1, and the flange protrusion 100c is formed on the flange 100, the gasket 1 There is no gap between the two, and the built-up portion 15 can provide volume, improving sealing performance.

Note that the shapes and configurations of the gasket 1, head cover 2, cylinder head 3, etc. are not limited to the illustrated examples or the above embodiments. Further, the gasket 1 is suitably used between two members having an arch portion 30 as shown in the figure, but is not limited to the above embodiment, and may be used in various seal structures for sealing between two members. good. Furthermore, depending on the location where the gasket 1 is applied, the application of the above-mentioned liquid gasket may not be necessary. The gasket 1 is not limited to an annular body, and may be partially provided, and the configuration of the protrusion 14 is not limited to the illustrated example. Furthermore, the shapes and configurations of the protruding portion 13a, the built-up portion 15, and the collar protruding portion 100c are not limited to the illustrated example. For example, the built-up portion 15 may be formed so that the length of the side on the flat-shaped portion 11 side is smaller than the length of the side of the arc-shaped portion 12 . Further, the shape of the flat portion 11 and the flat surfaces 21 and 31 is not limited to the flat shape shown in the figure, but may have a somewhat meandering portion.

1 Gasket 10 Gasket body 11 Flat shaped part 12 Arc shaped part 12a Tapered part 13 Corner part 13a Projection part 15 Built-up part 2 Head cover (one member)
20 groove 20d wall corner 21 flat surface 22 arc-shaped surface 23 corner surface 3 cylinder head (other member)
31 Flat-shaped surface 32 Arc-shaped surface 33 Square surface

Claims (6)

one member having a flat surface and an arcuate surface formed continuously therewith; a flat surface that merges with the flat surface of the one member; and an arc formed continuously therewith and merges with the arcuate surface. A gasket made of an elastic body and having a shaped surface and sealing between the one member and the other member that faces and joins,
a gasket body that is fitted into and attached to a groove formed in the one member;
and a flange formed to protrude in the groove width direction from both sides of the gasket body,
The gasket body includes a flat portion formed along the flat surfaces of the one member and the other member, and an arcuate portion formed along the arcuate surfaces of the one member and the other member. , a corner portion where the flat portion and the arcuate portion intersect;
The arcuate portion has a tapered portion in which a surface opposite to the arcuate surface of the other member is inclined toward the flat portion;
The gasket is characterized in that the corner portion has a protrusion formed to protrude from the flat portion toward the flat surface of the other member. In claim 1,
The gasket is characterized in that the thickness of the flange portion of the protruding portion is formed such that the thickness gradually increases from a portion corresponding to the flat-shaped portion to a portion corresponding to the corner portion. In claim 2,
The gasket is characterized in that a lower surface of the flange portion of the protruding portion is formed to be inclined toward a portion corresponding to the corner portion. In any one of claims 1 to 3,
A gasket characterized in that a built-up portion thicker than other portions is formed between the corner portion and the flange portion continuous with the corner portion. In claim 4,
The gasket is characterized in that the built-up portion is formed so that the width thereof gradually increases toward the flange portion in cross-sectional view. In claim 4 or claim 5,
The gasket is characterized in that the built-up portion has a thickness such that it comes into elastic contact with wall corner portions on both sides forming the groove when the gasket main body is attached to the groove.

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