JPH09196178A - Metallic cylinder head gasket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a stress change in a bead base board and bending stress acting on a grommet part by constituting the whole circumference of holes for combustion chambers out of a full bead in an adjusting plate bead of an adjusting plate, and arranging a grommet plate bead formed of a full bead overlapping with the adjusting plate bead on a grommet plate. SOLUTION: A shape of a base board bead 2 of a bead base board 3 is deformed in a half bead H around holes 1 for respective combustion chambers though it is a full bead F1 between the holes 1 and 1 for the combustion chambers in response to a strength difference in rigidity different between a cylinder head and a bore of a cylinder block and around the bore continuing with this. In an adjusting plate bead 5 of an adjusting plate 6, the whole circumference of a hole 4 for a combustion chamber is composed of a full bead F2. A grommet plate bead 11 formed of a full bead F3 overlapping with the adjusting plate bead 5 is arranged on a grommet plate 8, and the adjusting plate 6 is embraced and held by the grommet plate 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal cylinder head gasket used for sealing a joint surface between a cylinder head and a cylinder block of an internal combustion engine, particularly a multi-cylinder internal combustion engine, and more particularly to a combustion chamber hole. The present invention relates to a metal cylinder head gasket in which two bead substrates made of elastic metal plates each having a bead portion formed in a contour shape along each peripheral edge and a grommet plate are laminated.

[0002]

2. Description of the Related Art Recent internal combustion engines tend to be lighter with higher output and higher temperature. Instead of conventional castings, both the cylinder head, the cylinder block, or only the cylinder head are made of aluminum. But,
When such a low-rigidity material is used, the rigidity of the cylinder head and the cylinder block tends to decrease during operation, and the relative displacement between the two tends to increase.

A metal cylinder head gasket having a bead formed so as to seal the deck surfaces of the cylinder head and the cylinder block is used at a joint portion of the cylinder head and the cylinder block constituting such an internal combustion engine, and a bolt, etc. An elastic seal line is formed on the deck surface by the coupling force of the fastening means to achieve the seal.

However, when the cylinder head is fastened to the cylinder block by the fastening bolts via the metal cylinder head gasket, the cylinder head is bent by the bolt fastening force, and in particular, the gap around the combustion chamber becomes large and distortion occurs. It happens. The formation of such a gap and the generation of strain may cause the combustion gas to leak, stain the metal cylinder head gasket interposed in the joint, or reduce the sealing performance due to the accumulation of the contained substance. In addition, when used, the deck surface clearance around the combustion chamber expands and contracts due to the effect of combustion gas pressure and engine heat, which causes settling in the beads of the metal cylinder head gasket, reducing the bolt fastening force and reducing the metal cylinder head gasket's strength. There are inconveniences such as reduction of the sealing effect.

In order to solve such inconvenience, for example, as disclosed in Japanese Patent Laid-Open No. 64-73157, two bead substrates made of an elastic metal plate having beads formed along the periphery of the bore. In between, by laminating the cylinder head side as a grommet plate and the cylinder block side as an intermediate plate, by folding back the inner peripheral edge of the grommet plate to the cylinder block side, and by including the inner peripheral edge of the intermediate plate, The metal structure is designed to compensate for the deck surface gap around the combustion chamber to prevent the bead function from deteriorating and to equalize the spring force of the bead substrate at the bead site to improve the sealing performance and durability. Cylinder head gasket (Prior Art 1) and Kaikai 4-34
As disclosed in Japanese Laid-Open Patent Publication No. 562, an intermediate plate is provided between two bead substrates made of an elastic metal plate having combustion chamber holes arranged in parallel with each other and forming beads along the combustion chamber holes. In the metal cylinder head gasket laminated in a sandwich, the bead substrate and the intermediate plate, which are the cylinder block side, are folded and wrapped around the grommet plate to the cylinder head side and fixed, and the intermediate plate along the beads of the bead substrate. A metal cylinder head gasket (Prior Art 2) having a structure in which an intermediate plate bead that is convex toward the cylinder head side is formed is known.

[0006]

Since the prior arts 1 and 2 described above each have a laminated structure of four sheets, both in terms of material and manufacturing, as compared with a metal cylinder head gasket having a laminated structure of three sheets. It not only causes cost increase,
Particularly in Prior Art 1, since the inner peripheral edge of the grommet plate is folded back to the cylinder block side to enclose the peripheral edge of the intermediate plate, this is sandwiched between the bead substrates on both sides and between the cylinder head and the cylinder block. When compressed to the fully bent state, the folded portions of the grommet plate folded back to the cylinder block side all act as shims on the bead portion on one side, resulting in stress on the bead substrate on the cylinder head side with respect to the bead substrate on the cylinder block side. Since the swing becomes large, and large bending stress and stress swing are generated in the grommet portion, cracks and fatigue are caused in the beads on the grommet plate and the cylinder head side.

Also in the prior art 2, since the bead of the bead substrate on the cylinder head side and the bead of the intermediate plate are in contact with each other at the top, they are likely to become unstable under load, and also the reduction of the sealing performance and the cracking of the bead portion occur. There was a problem to be solved in that it easily occurs.

In the present invention, in the prior arts 1 and 2, there is a difference in rigidity between the bores of the cylinder head and the cylinder block and the surrounding bores, but the bores and the bores rotate. Since the bead structure is the same, the metal cylinder head gasket does not adapt to the distortion of the cylinder head and the cylinder block caused by the difference in the rigidity, and the sufficient sealability is still secured and the settling and cracking of the bead are prevented. It was made by focusing on the point that it is not possible to solve the problem, and because of the metal cylinder head gasket of the three laminated structure which is advantageous in terms of material and manufacturing, stress fluctuation of the bead substrate and grommet part Stable sealing performance by reducing the bending stress that acts on the bead, preventing damage to the beads and grommets, and reducing the sealing performance. It is an object to provide an inexpensive metal cylinder head gasket which can be maintained for long.

[0009]

The metal cylinder head gasket of the present invention is a bead substrate (3) made of an elastic metal plate in which substrate beads (2) are formed along the periphery of the combustion chamber holes (1) arranged in parallel. ), And an adjusting plate (6) made of an elastic metal plate with adjusting plate beads (5) formed along the perimeter of the combustion chamber holes (4) juxtaposed with each other, and the combustion chamber holes (1), (4). The grommet plate (8) formed by arranging the smaller holes (7) for the combustion chamber in parallel with each other is sequentially laminated so that the beads (2) and (5) are vertically stacked, and the adjustment plate (6) is A metal cylinder head in which the opening edge of the combustion chamber hole (4) is held and fixed by the opening edge of the combustion chamber small hole (7) of the grommet plate (8) to form the parallel bores (10). In the gasket G, the substrate bead (2) of the bead substrate (3) is a full bead (F1) at least between the holes (1) and (1) for the combustion chamber, but each combustion chamber continuous to this Around the hole (1), it is transformed into a half bead (H) (a full bead has a chevron cross section, and a half bead has a stepped cross section. The adjusting plate bead (5) of the adjusting plate (6) is
A full bead (F2) is formed around the entire circumference of the combustion chamber hole (4), and a grommet plate bead (11) formed by a full bead (F3) that overlaps the adjustment plate bead (5) on the grommet plate (8). Is provided.

It should be noted that the stress fluctuation of the bead substrate and the bending stress acting on the grommet portion are reduced, the bead portion and the grommet portion are prevented from being damaged, and the sealing performance is prevented from being reduced. Therefore, the basic configuration is provided with any or all of the following configurations.

(1) The combustion chamber hole (1) of the bead substrate (3),
The substrate bead (2) consisting of the full bead (F1) formed between the (1) and the rising root line of the substrate bead (2).
(9) is formed into a straight line with a predetermined width (W). (2) Hold the holding width of the adjustment plate (6) with the grommet plate (8)
Widen between the bores (10) and (10) and narrow around the continuous bore (10). (3) The thickness of the holding surface of the adjusting plate (6) by the grommet plate (8) is increased between the bores (10) and (10), and the continuous bore is formed.
(10) Crush around and thin. (4) Bead substrate (3), adjusting plate (6) and grommet plate
A heat resistant rubber or resin is applied to each laminated contact surface in (8) and each surface in contact with the cylinder head and the cylinder block.

[0012]

The metal cylinder head gasket according to the present invention described above corresponds to the difference in rigidity between the cylinder head and the cylinder block bores (10) and (10) and around the continuous bore (10). The shape of the substrate bead (2) of the bead substrate (3) is a full bead (F1) between the combustion chamber holes (1) and (1), but a half bead around each combustion chamber (1).
(H), and the adjustment plate bead of the adjustment plate (6)
(5) is a full bead (F2) along the entire circumference of the combustion chamber hole (1), and the adjustment plate bead is attached to the grommet plate (8).
By providing the grommet plate bead (11) formed with the full bead (F3) that overlaps with (5), the distribution of the seal surface pressure is optimized, and further, the adjustment plate bead (5) is prevented from settling and the sealing performance is maintained for a long time. Not only is it possible, but also the bead board by holding the adjustment plate (6) with the grommet plate (8).
(3) and the bead of the adjusting plate (6), the grommet turn-back portion exerts a stopper function and can avoid the fully bent state, so that it acts to maintain effective sealing performance for a longer period of time. .

[0013]

DETAILED DESCRIPTION OF THE INVENTION AND

1 is a partial plan view of a metal cylinder head gasket according to the present invention, FIG. 2 is a first embodiment, which is an exploded sectional view taken along the line AA of FIG. 1, and FIG. 3 is a sectional view of FIG. -B
1 is an enlarged end view taken along the line C-C of FIG. 1, and FIG. 5 is the second embodiment and is an enlarged plan view between the bores (10) and (10) shown in FIG. 1D. FIG. 6 shows Example 3,
FIG. 7 is a plan view of a portion around the bore (10) showing a state where the bead substrate (3) on the cylinder head side is removed, and FIG. 7 is an enlarged sectional view taken along line AA of FIG. is there.

(First Embodiment) The metal cylinder head gasket shown in FIGS. 1 to 4 has holes for combustion chambers arranged in parallel.
A substrate bead (2) was formed along the opening edge of (1), 0.3m
m SUS 301 3 / 4H bead board (3) and adjusting plate beads (5) formed along the opening edges of the combustion chamber holes (4) arranged side by side, 0.6 mm thickness, SECC adjustment A plate (6) and a grommet plate (8) made of SUS 304 with a thickness of 0.15 mm, which is formed by arranging the combustion chamber holes (1) and (4) smaller in diameter than the combustion chamber holes (7) in parallel. , And stack them one by one, and hold and fix the opening edge of the combustion chamber hole (4) of the adjusting plate (6) by folding back the opening edge of the combustion chamber small hole (7) of the grommet plate (8) to the cylinder head side. Then
In forming the parallel bores (10), the bead substrate
As shown in Fig. 2 to Fig. 4, the substrate bead (2) of (3) is filled with a full bead (F) between the combustion chamber holes (1), (1) and both ends.
1), but the structure is such that it is transformed into a half bead (H) around each of the combustion chambers (1) following this, and the adjustment plate (6)
Adjusting plate bead (5) is composed of full bead (F2),
The grommet plate (8) is provided with a grommet plate bead (11) formed of a full bead (F3) overlapping the adjusting plate bead (5), and is provided between the bores (10) and (10) (Fig. 3) and both ends ( In Fig. 4), the full bead (F1) of the substrate bead (2) and the adjustment plate bead
(5) Full bead (F2) and grommet plate bead (11) full bead (F3) overlap, and in other parts, half bead (H) and full bead (F2) and full bead (F3) are overlapped. It is the configured configuration.

(Example 2) In the metal cylinder head gasket of Example 1, the full bead (F1) substrate bead (2) formed between the combustion chamber holes (1) and (1) of the bead substrate (3) was used. 5), the rising base line 9 of the substrate bead 2 is formed in a straight line by a predetermined width (W) (about 15 to 30 mm) as shown in FIG.

(Embodiment 3) In the metal cylinder head gasket of Embodiment 1 or 2, as shown in FIG.
The holding width (b ₁ ) of the adjusting plate (6) by the grommet plate (8) is 2.0 to 3.0 mm between the bores (10) and (10), and the holding around the continuous bore (10). In the width (b ₂ ), the holding width
The width is 1.0 to 1.5 mm, which is narrower than (b ₁ ).

(Embodiment 4) In the metal cylinder head gasket of Embodiment 1, 2 or 3, as shown in FIG. 7, the thickness of the holding surface by the grommet plate (8) of the adjusting plate (6).
(t ₁ ) between the bores (10) and (10) is 0.6
The thickness (t ₂ ) around the continuous bore (10) is crushed and thinned to 0.550 mm.

Although not shown in the drawings for explaining the above-mentioned respective embodiments, the bead substrate (3) and the adjusting plate are not shown.
Heat-resistant rubber or resin (for example, fluororubber, silicone rubber, etc.) is applied to each laminated contact surface of (6) and grommet plate (8) and the surface that contacts the cylinder head and cylinder block.
May be applied to improve the adhesion between the cylinder head, the cylinder block, and each component plate, to eliminate the leak caused by the presence of scratches at each substrate manufacturing stage, and to secure a better sealing property. .

[0019]

EFFECT OF THE INVENTION In the metal cylinder head gasket according to the present invention, the shape of the substrate bead (2) of the bead substrate (3) is a full bead (F1) between the combustion chamber holes (1) and (1). Is transformed into a half bead (H) around each combustion chamber (1),
Also, adjust the bead (5) of the adjustment plate (6) to the hole for the combustion chamber.
By making the entire circumference of (1) a full bead (F2), the grommet plate (8) is provided with a grommet plate bead (11) formed of a full bead (F3) overlapping the adjusting plate bead (5), Between the bores (10), (10) and the continuous bores (10)
The seal surface pressure distribution is optimized according to the difference in the rigidity of the surroundings, and the grommet plate bead (11) prevents the adjusting plate bead (5) from settling, thus improving the sealing performance by forming a seal line. It is possible to improve and maintain it for a long time.

Further, by holding the adjusting plate (6) with the grommet plate (8), the grommet turn-back portion is provided for each bead of the bead substrate (3), the adjusting plate (6) and the grommet plate (8). By exerting a stopper function and avoiding a fully bent state, it is possible to further improve the effective sealing performance and maintain it for a long period of time. It is possible to provide a metal cylinder head gasket having a good balance of stress, a stress variation of the bead substrate (3) on the cylinder head side, which has a relatively large displacement variation, and an excellent sealing property, at low cost.

The bead substrate according to claim 2
The substrate bead (2) consisting of the full bead (F1) formed between the combustion chamber holes (1) and (1) of (3) is the substrate bead (2).
When the rising root line (9) is formed into a straight line with a predetermined width (W), the space between the bores (10) and (10) where the space is the narrowest and the part where the space gradually increases A full bead (F1) that is inversely proportional to the rigidity is formed, and the bore (10), (10)
The distribution of the seal surface pressure in the space and its vicinity can be optimized.

Further, as described in claim 3, the holding width of the adjusting plate (6) by the grommet plate (8) is set to the bores (10), (10).
When the width is widened between the bores (10) and narrowed around the continuous bore (10), the surface pressure between the bores (10) and (10) is dispersed in addition to the above-mentioned action, resulting in an even average sealability. Can be secured.

Further, as described in claim 4, the adjusting plate
Set the thickness of the holding surface by the grommet plate (8) of (6) to the bore (1
When thickening between 0) and (10) and crushing around the continuous bore (10) to make it thinner, the deformation of the cylinder head between the deck surfaces between the bores (10) and (10) To further improve the sealing property.

Further, as described in claim 5, heat-resistant rubber or a heat-resistant rubber is provided on the surface of the bead substrate (3), the adjusting plate (6), and the grommet plate (8) that are in close contact with each other and the surface contacting the cylinder head and the cylinder block. When resin is applied, the adhesion between the cylinder head, cylinder block, and each component plate is improved, and the leakage due to the existence of scratches at the stage of manufacturing each substrate is also eliminated, ensuring even better sealing performance. Like

[Brief description of drawings]

FIG. 1 is a partial plan view of a metal cylinder head gasket of the present invention.

FIG. 2 is a disassembled sectional view taken along the line AA of FIG. 1 showing the first embodiment of the present invention.

FIG. 3 is an enlarged end view taken along line BB of FIG.

FIG. 4 is an enlarged end view taken along the line CC of FIG.

5 is a second embodiment of the present invention and is an enlarged plan view enlarged cross-sectional view of a portion D in FIG. 1. FIG.

FIG. 6 is a plan view of a portion around the bore (10) in a state in which the bead substrate (3) on the cylinder head side is removed according to the third embodiment of the present invention.

FIG. 7 is an enlarged cross-sectional view taken along line AA of FIG. 1 according to the fourth embodiment of the present invention.

[Explanation of symbols]

 (1), (4) Combustion chamber hole (2) Substrate bead (3) Bead substrate (5) Adjustment plate bead (6) Adjustment plate (7) Small combustion chamber hole (8) Grommet plate (9) Root line ( 10) Bore (11) Grommet plate beads (F1), (F2), (F3) Full bead (H) Half bead

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Uemura 2-1-1 Kano, Higashi-Osaka City Nihon Gasket Co., Ltd. Hiroshi Uchimura (72) Inventor Tomoyoshi Uogari 2-1-1 Kano, Higashi-Osaka City Nippon Gasket Co., Ltd. Tomoyoshi Uchigyo

Claims (5)

[Claims] 1. A bead substrate (3) made of an elastic metal plate in which substrate beads (2) are formed along the periphery of the parallel combustion chamber holes (1) and the periphery of the parallel combustion chamber holes (4). Adjusting plate (6) made of elastic metal plate with adjusting plate beads (5) formed along
And the combustion chamber holes (1) and (4) with a smaller diameter than the combustion chamber holes.
Grommet plate (8) formed by arranging (7) side by side is laminated so that each bead (2), (5) part overlaps vertically, and combustion chamber hole (4) of adjusting plate (6) Open the opening edge of the grommet plate
In a metal cylinder head gasket G formed with parallel bores (10) by holding and fixing at the opening edge of the combustion chamber small hole (7) of (8), the substrate bead (2) of the bead substrate (3) is formed. ) Is a full bead (F1) at least between the combustion chamber holes (1) and (1), but a half bead around each of the combustion chamber holes (1) that follows it.
(H), the adjusting plate bead (5) of the adjusting plate (6) has a full bead (F2) along the entire circumference of the combustion chamber hole (4).
And a grommet plate bead (11) formed of a full bead (F3) overlapping the adjusting plate bead (5) is further provided on the grommet plate (8). 2. Combustion chamber holes (1), (1) in a bead substrate (3)
Substrate beads consisting of full beads (F1) formed in the space between
(2) is the rising root line (9) of the substrate bead (2)
The metal cylinder head gasket according to claim 1, wherein the metal cylinder head gasket is formed in a straight line having a predetermined width (W). 3. The holding width of the adjusting plate (6) by the grommet plate (8) is widened between the bores (10), (10) and narrowed around the continuous bore (10). The metal cylinder head gasket according to 1 or 2. 4. The thickness of the holding surface of the adjusting plate (6) by the grommet plate (8) is made thicker between the bores (10), (10) and crushed around the continuous bore (10). Claims 1 and 2 thinned
Alternatively, the metal cylinder head gasket described in 3. 5. A heat-resistant rubber or resin is applied to the surface of the bead substrate (3), the adjusting plate (6), and the grommet plate (8) that are in close contact with each other and the surface that contacts the cylinder head and the cylinder block. The metal cylinder head gasket according to 2, 3 or 4.