JPH0139878Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention relates to gaskets for internal combustion engines, and is particularly effective in sealing not only cylinder bores but also oil holes, water holes, exhaust ports, etc. The present invention relates to a gasket for internal combustion engines that can be used for internal combustion engines.

[Conventional technology]

In a gasket for an internal combustion engine, the base plate has an opening of a predetermined size for the cylinder bore, a protruding (V-shaped) bead surrounding this opening, and a similar protrusion for sealing ports such as oil holes. A striped bead is formed, and the convex bead prevents gas and liquid from leaking.

[Problem to be solved by the invention] However, for example, in a four-cylinder parallel internal combustion engine installed in a motorcycle, a large temperature difference occurs in the cylinder head, and as a result, the cylinder head itself tends to deform. However, a gasket for an internal combustion engine in which a convex bead is simply formed on a single substrate has the disadvantage that leakage of gas or liquid cannot be effectively prevented.

In addition, when the convex beads formed on the substrate are compressed and deformed, due to their high spring constant, they may be difficult to slide or deform in the horizontal direction, and excessive force is concentrated at the top. There is a risk of damaging the deck surfaces of the cylinder head, cylinder block, etc.

Furthermore, when a gasket for an internal combustion engine is compressed and deformed due to excessive clamping pressure, the protruding beads may expand completely into a flat shape, resulting in sagging or cracks in the protruding beads. Therefore, the elastic restoring force tends to decrease and airtightness cannot be maintained sufficiently.

[Purpose of invention]

Therefore, the purpose of this invention was to eliminate the above-mentioned disadvantages by effectively sealing not only the cylinder bore but also the oil hole, water hole, exhaust port, etc. by using the sloped part formed on the substrate made of a hard metal plate. In addition, even when used with excessive clamping pressure, the slope part is prevented from being completely flattened, the elastic restoring force of the slope part is maintained, and appropriate airtightness is maintained. The objective is to realize a gasket for internal combustion engines that can be used for internal combustion engines.

[Means for solving problems]

In order to achieve this purpose, this invention has an opening of a predetermined size in a substrate made of a hard metal plate, a sloped part surrounding this opening, and a first bent part that is one end of this sloped part. A flat portion is formed that is continuous with the substrate main body portion and the second bent portion that is the other end of the sloped portion, is substantially parallel to the substrate main portion, and is located on the opening side, and has a flat portion that is harder than the substrate. A first sub-plate made of a soft metal plate having a low surface area is provided in contact with the substrate body on one side of the substrate, and a peripheral edge formed by folding the first sub-plate on the opening side forms the slope. and the flat portion, and the first sub-plate edge portion of the first sub-plate that is continuous with the peripheral edge portion is brought into contact with the substrate main body portion.
provided substantially parallel to the first sub-plate main body portion of the sub-plate;
The flat portion is provided in contact with the first sub-plate edge, and the first sub-plate end face of the first sub-plate edge is connected to the first sub-plate, which is a continuous portion of the substrate main body and the sloped portion. The first bending portion is located slightly closer to the board main body, and on the other side of the board, the first sub-board edge is located at substantially the same position as the end edge of the first sub-board, and is substantially parallel to the board main body. A second sub-plate made of a soft metal plate having a second sub-plate main body portion located therein is provided, and an end edge of the second sub-plate on the side of the opening is bent at the stepped portion to form the The first sub-plate end edge is provided so as to overlap the substrate-side surface, and the second sub-plate end surface of the second sub-plate end edge is provided at approximately the same position as the first bent part, and the slope portion, the substrate main body portion, and the second
A third sub-plate is provided in contact with the second sub-plate main body within the space formed between the sub-plates, and this third
A third sub-plate end surface of a third sub-plate edge portion on the opening side that is continuous with the third sub-plate main body portion of the sub-plate is not brought into contact with the stepped portion of the second sub-plate, but is spaced a little apart. It is characterized by having been established.

[Effect]

According to the configuration of this invention, when the gasket for an internal combustion engine is compressed and deformed by the clamping pressure, the substrate main body easily slides along the first sub-plate main body, and the flat part is moved along the first sub-plate. Since it easily slides along the main body without biting in, the slope part can easily slide and deform in the horizontal direction, preventing complex forces from acting on the slope part, and improving the function of the slope part. can be retained.

In addition, when the gasket for an internal combustion engine is compressively deformed and used in a state where the main board part and the third sub-plate do not come into contact with each other, stress concentration occurs at the first and second bent parts. As a result, sealing surface pressure can be concentrated and sealing can be achieved effectively.

Furthermore, due to excessive clamping pressure, the board main body and the third
When the gasket for an internal combustion engine is compressively deformed and used in a state where the sub-plates are in contact with each other, the substrate main body, the first sub-plate main body, the second sub-plate main body, and the third sub-plate are overlapped. Since the board thickness is larger than that of the slope portion, the board thickness is the sum of the board main body, the first sub-board main body, the second sub-board main body, and the third sub-board. Since the slope part is not completely flattened, the elastic restoring force of the slope part is maintained, even if the gap between the surfaces to be sealed becomes large. Even in such a case, the elastic restoring force of the slope portion, which easily slides and deforms in the horizontal direction, prevents the sealing effect from deteriorating and maintains appropriate airtightness.

〔Example〕

Embodiments of this invention will be described in detail and specifically below based on the drawings.

1 to 5 show examples of this invention. In the figure, 10 is a gasket for an internal combustion engine. This internal combustion engine gasket 10 includes a substrate 1, a first sub-plate 2 provided on one side of the substrate 1, and a second sub-plate 2' provided on the other side of the substrate 1.
and a third sub-plate 2'' provided between the substrate 1 and the second sub-plate 2'.

The substrate 1 is made of a hard metal plate having a hardness of, for example, HV200 to HV450 and a thickness t.

The first and second sub-plates 2, 2' are made of soft metal plates having a hardness lower than that of the substrate 1, for example HV20 to 150, and a thickness t that is the same as the thickness t of the substrate 1.

The third sub-plate 2'' is made of a metal plate having, for example, the same hardness as the substrate 1 and the same thickness t as the thickness t of the substrate 1.

For example, an opening 13 of a predetermined size (see FIG. 1) having a diameter slightly larger than the diameter of the cylinder bore 12 formed in the cylinder block 11 shown in FIG. 3 is formed in the substrate 1. In the vicinity of the opening 13, to surround the opening 13, there is a sloped portion a, a substrate main body portion 1c continuous to the first bent portion 14 which is one end of the sloped portion a, and a first bent portion which is the other end of the sloped portion a. A flat portion 1b is formed which is continuous with the two-folded portion 15, is approximately parallel to the substrate main body portion 1c, and is located on the opening portion 13 side. The substrate main body portion 1c and the flat portion 1b are located substantially parallel to each other and are separated by a step distance S by the slope portion a.

Therefore, the substrate 1 is formed in the shape of a so-called disc spring around the opening 13, and is formed in a stepped shape by the substrate main body portion 1c, the slope portion a, and the flat portion 1b, that is, its cross section is formed in a step shape. become.

The first sub-plate main body 2c of the first sub-plate 2 is provided in contact with the outer surface of the substrate main body 1c, which is the opposite side of the substrate 1 from which the sloped portion a and the flat portion 1b are formed.

Also, the cross section U on the opening 13 side of the first sub-plate 2
The peripheral edge portion 2b formed by folding back into a letter shape encloses the slope portion a and the flat portion 1b. This peripheral part 2
The first sub-plate end edge 2a continuous to b is provided so as to be located substantially parallel to the first sub-plate main body 2c, that is, to the board main body 1c.

The flat portion 1b of the substrate 1 is provided in contact with the inner surface of the first sub-plate edge portion 2a. Further, the first sub-plate end surface 2d of the first sub-plate end edge 2a has a first bent portion 1 which is a continuous portion of the board main body portion 1c and the slope portion a.
It is provided at a position closer to the substrate main body portion 1c than the position No. 4.

Therefore, the substrate end surface 1 of the flat portion 1b of the substrate 1
The circumferential surface 2e of the circumferential edge portion 2b of the first sub-plate 2 that covers the
This forms a bore hole 20 having approximately the same diameter as the inner diameter of the cylinder bore 12. Further, by overlapping the thickness t of the basic main body portion 1c of the substrate 1 and the thickness t of the second sub-plate main body portion 2c of the first sub-plate 2, a first overlapping thickness H is formed. It turns out.

On the other hand, the second sub-plate 2' is disposed on the other side of the substrate 1 substantially parallel to the substrate main body portion 1c. The second sub-plate body part 2'c of the second sub-plate 2' is located at approximately the same position as the first sub-plate edge part 2a and at the substrate main body part 1c.
It is located approximately parallel to the Further, the second sub-plate main body part 2'c has a continuous second sub-plate edge part 2'b which is bent at the stepped part 2's so as to overlap with the first sub-plate edge part 2a. It is provided. The second sub-plate edge 2'b is provided so as to overlap the surface of the first sub-plate edge 2a on the substrate 1 side. Further, at this time, the second sub-plate end surface 2'd of the second sub-plate end edge 2'b is provided at approximately the same position as the first bent part 14.

As a result, the substrate main body portion 1c, the slope portion a and the second
A space 16 is formed between the sub-plates 2'.

Therefore, in this space 16, a third sub-plate 2'' is stacked and provided in contact with the second sub-plate main body portion 2'c of the second sub-plate 2'. That is, the third sub-plate 2'' is provided. the third
The sub-plate main body part 2''c is provided in a stacked manner in contact with the second sub-plate main body part 2'c, and a third sub-plate end on the side of the opening 13 that is continuous with the third sub-plate main body part 2''c. The third auxiliary plate end face 2''d of the edge 2''b is provided with a slight distance from the stepped portion 2's of the second auxiliary plate 2' without coming into contact with it.
As a result, the second sub-plate body portion 2'c of the second sub-plate 2'
By overlapping the thickness t of the third sub-plate main body portion 2''c of the third sub-plate 2'', a second overlapping thickness that is the same as the first overlapping thickness H is obtained. This results in the formation of a .

Gasket 1 for internal combustion engine configured in this way
As shown in FIG. 3, for example, the cylinder 0 is interposed between the deck surface 11a of the cylinder block 11 and the deck surface 17a of the cylinder head 17 constituting the internal combustion engine, and is compressed and deformed to release combustion gas from the combustion chamber 18 side. This is to prevent leaks. In FIG. 1, reference numeral 19 is a bolt hole formed around the bore hole 20 for inserting a fastening bolt (not shown) for fastening the cylinder head 17 to the cylinder block 11.

Next, the operation of this embodiment will be explained.

As shown in FIG.
A first sub-plate 2 is placed in contact with the cylinder block 11, and a second sub-plate 2' is placed in contact with the deck surface 11a of the cylinder block 11.

As shown in FIG. 4, the internal combustion engine gasket 10 is compressed and deformed so as to narrow the space 16 by the fastening force of the fastening bolt that fastens the cylinder head 17 to the cylinder block 11.
At this time, the board main body part 1c and the first sub-board main body part 2c
The flat part 1b easily slides on the first sub-plate edge 2a without biting into the first sub-plate edge 2a, and the slope part a of the substrate 1' is horizontally spreads easily. Therefore, it is possible to prevent complex forces from acting on the slope portion a, and to maintain the function of the slope portion a well.

The gasket 10 for an internal combustion engine is, for example, as shown in FIG.
There are cases where the third sub-plate main body portion 2''c of the third sub-plate 2'' does not come into contact with each other, and is used with only a gap D formed.
At this time, the substrate main body portion 1c and the flat portion 1b are located close to each other with a small step distance S1.

In this case, the gasket 10 for an internal combustion engine has an inclined surface a extending horizontally between the deck surface 11a of the cylinder block 11 and the deck surface 17a of the cylinder head 17, so that the gasket 10 has a flat surface in particular, where the substrate 1 is bent. By stress concentration occurring at the first portion X near the first bent portion 14, the pressing force is strongly concentrated on the deck surface 17a side of the cylinder head 17, and the stress is concentrated near the second bent portion 15 which has been bent. By stress concentration occurring at the second portion Y, the pressing force is strongly concentrated on the deck surface 11a of the cylinder block 11. Therefore, the internal combustion engine gasket 10 concentrates the sealing surface pressure on the deck surface 17a of the cylinder head 17 at the first portion X, and also concentrates the seal surface pressure on the deck surface 11a of the cylinder block 11.
The sealing surface pressure can be concentrated at the second portion Y, and the seal between the decking surface 17a of the cylinder head 17 and the decking surface 11a of the cylinder block 11 can be effectively achieved.

Further, a first sub-plate main body portion 2c having a thickness of t is interposed between the substrate 1 and the deck surface 17a of the cylinder head 17 at the first portion X that concentrates the sealing surface pressure on the deck surface 17a of the cylinder head 17. , deck surface 11a of cylinder block 11
At the second portion Y where the sealing surface pressure is concentrated on the first sub-plate edge portion 2a having a thickness of t, the flat portion 1 of the substrate 1
b and the deck surface 11a of the cylinder block 11, the pressing force generated by compressive deformation of the slope portion a is applied to the first portion X and the second portion Y.
Since it is possible to apply substantially the same seal surface pressure to the deck surface 17a of the cylinder head 17 and the deck surface 11a of the cylinder block 11, stable sealing performance can be obtained.

Furthermore, when the gasket 10 for an internal combustion engine is compressed and deformed, the substrate body portion 1c of the substrate 1 smoothly slides on the first sub-plate body portion 2c of the first sub-plate 2, and the flat portion 1b of the substrate 1 is It slides well on the inner surface of the first sub-plate end edge 2a, and since the cross section is formed into a step shape by the substrate main body 1c, the sloped part a, and the flat part 1b, the spring constant is small. ,
The slope portion a can be easily deformed in the horizontal direction, and the substrate 1 can be prevented from being deformed in a complicated manner.
As a result, the function of the slope portion a can be maintained well.

Furthermore, the flat portion 1b improves sliding properties to prevent the substrate end surface 1d of the substrate 1 from biting into the first sub-plate edge 2a of the first sub-plate 2.
It is possible to improve the resilience of

Further, the irregular surface of the deck surface 17a of the cylinder head 17 is compensated for by the first sub-plate 2 made of a soft metal plate, and the deck surface of the cylinder block 11 is compensated for by the second sub-plate 2' made of a soft metal plate. It is possible to compensate for the uneven surface of 11a and effectively prevent leakage of combustion gas.

On the other hand, as shown in FIG. 5, the internal combustion engine gasket 10 is damaged due to excessive clamping pressure.
and the third sub-plate 2'' may be used in contact with each other.

In this case, the board main body 1c of the board 1, the first sub-board main body 2c of the first sub-board 2, the second sub-board main body 2'c of the second sub-board 2', and the third sub-board main body 2'c of the third sub-board 2'' 3 sub-board main body part 2''c is laminated in close contact with the first overlapping part L, and the board main body part 1c and the first sub-board main body part have the same thickness as this first overlapping part L. 2c, the first sub-plate edge 2a, and the second sub-plate edge 2'b are laminated in close contact with each other to form a second overlapping portion M.

In the first and second overlapping parts L and M, four metal plates are laminated, but in the slope part N where the slope part a is located, the first sub-plate main body part 2c
Three metal plates including the flat portion 1b and the first sub-plate edge portion 2a are stacked.

Therefore, in this case, the internal combustion engine gasket 10
are mainly the first and second overlapping parts L and M, which have large plate thicknesses.
At the slope part N, the seal is achieved.
Depending on the thickness of the first and second overlapping parts M and N, the first sub-plate main body part 2c, the peripheral edge part 2b, and the first sub-plate edge part 2a
An annular gap R corresponding to the thickness t of one metal plate is formed between the two, and the slope part a and the flat part 1b are located within this gap R, and the slope part a is completely flat. It will not be extended to As a result, the slope part a can be elastically deformed within a predetermined range, that is, within the gap R, and the elastic restoring force of the slope part a can be maintained, so that the slope part a does not sag or crack. As a result, even if cylinder bore 1
Cylinder head 1 due to heat effects etc. around 2.
Even if the gap between the deck surface 17a of No. 7 and the deck surface 11a of the cylinder block 11 becomes large, the easy sliding and deformation of the slope portion a increases the followability and maintains appropriate airtightness. It is possible to improve the sealing performance and extend the service life.

Also, at this time, the thickness t of the board body portion 1c and the first
The first superposed thickness H obtained by superimposing the thickness t of the sub-plate main body part 2c, the thickness t of the second sub-plate main body part 2'c, and the thickness t of the third sub-plate main body part 2''c are Since the superposed second superimposed thickness H becomes the same thickness, when the internal combustion engine gasket 10 is compressively deformed, the slope portion a is smoothly deformed to avoid complicated deformation. One end side of a is held between the first sub-plate main body part 2c and the second sub-plate edge part 2'b, and the flat part 1b on the other end side of the slope part a is held by the first sub-plate edge part 1b.
By making strong contact with
By compressing and deforming both sides in the same state, it is possible to avoid unnecessary deviation and deformation of the slope part a, and to prevent functional deterioration of the slope part a.

Furthermore, in this case, since the first and second overlapping parts M and N that perform the sealing function are not directly arranged around the cylinder bore 12, functional deterioration of the first and second overlapping parts M and N is prevented, A good seal can be maintained.

[Effect of idea]

As is clear from the above detailed description, according to this invention, an opening of a predetermined size is formed in a substrate made of a hard metal plate, a slope portion surrounding the opening, and a first bent portion that is one end of the slope portion. The substrate body is continuous with the substrate body and the flat portion is continuous with the second bent portion, which is the other end of the sloped portion, and is approximately parallel to the substrate body and located on the opening side. A first sub-plate made of a low soft metal plate is provided in contact with the main body of the board on one side of the board, and the slope part and the flat part are covered by the peripheral part formed by folding back the first sub-plate on the opening side. The first sub-plate edge portion of the first sub-plate that is wrapped and continuous with the peripheral edge portion is positioned substantially parallel to the first sub-plate main body portion of the first sub-plate that is brought into contact with the substrate main body portion. , the flat portion is provided in contact with the flat portion of the first sub-plate edge, and the first sub-plate end surface of the first sub-plate edge is provided with a first fold, which is a continuous portion of the board main body and the sloped portion. A second sub-plate is provided at a position slightly closer to the board main body than the position of the curved portion, and is located on the other side of the board at approximately the same position as the edge of the first sub-plate and substantially parallel to the board main body. A second sub-plate made of a soft metal plate having a main body is provided, and the edge of the second sub-plate on the opening side is bent at the step to form a substrate at the edge of the first sub-plate. The end surface of the second sub-board is provided at approximately the same position as the first bent part, and the edge surface of the second sub-board is provided so as to overlap with the side surface, and the end face of the second sub-board is provided at approximately the same position as the first bent part, and between the slope part, the main body part of the board, and the second sub-board. The third sub-plate is provided in contact with the second sub-plate main body within the space formed, and the edge of the third sub-plate on the opening side that is continuous with the third sub-plate main body is By configuring the gasket for an internal combustion engine by providing the end face of the third sub-plate with a slight distance from the stepped portion of the second sub-plate, the gasket for an internal combustion engine is compressed and deformed by the clamping pressure. In this case, the board main body easily slides along the first sub-board main body, and the flat part slides along the first sub-board main body.
Because it easily slides along the main body of the sub-plate without biting in, the slope section can easily slide and deform in the horizontal direction, preventing complex forces from acting on the slope section, and improving the function of the slope section. It can be held well and can prevent damage to the cylinder head, the deck surface of the cylinder block, etc.

In addition, when the gasket for an internal combustion engine is compressively deformed and used in a state where the main board part and the third sub-plate do not come into contact with each other, stress concentration occurs at the first and second bent parts. As a result, sealing surface pressure can be concentrated and sealing can be achieved effectively. In addition, in this case, if the thickness of the first sub-plate main body portion where the first bent portion is located and the thickness of the first sub-plate edge portion where the second bent portion is located are formed to be the same, the slope portion The pressing force generated by spreading can be distributed approximately evenly between the first bent portion side and the second bent portion side, thereby achieving stable sealing performance.

Furthermore, due to excessive clamping pressure, the board main body and the third
When the internal combustion engine gasket is compressively deformed and used in a state where the sub-plate is in contact with the sub-plate, the substrate main body, the first sub-plate main body, the second sub-plate main body, and the third sub-plate overlap. Since the board thickness is larger than that of the slope portion, the board thickness is the sum of the board main body, the first sub-board main body, the second sub-board main body, and the third sub-board. Since the slope part is not completely flattened, the elastic restoring force of the slope part is maintained, even if the gap between the surfaces to be sealed becomes large. Even in such a case, the elastic restoring force of the slope portion, which easily slides and deforms in the horizontal direction, prevents the sealing effect from deteriorating and maintains appropriate airtightness. Further, in this case, if the thickness of the substrate main body, the thickness of the first sub-plate main body, the thickness of the second sub-plate main body, and the thickness of the third sub-plate main body are formed to be the same, the gasket for an internal combustion engine can be When compressed and deformed, the sloped portion deforms smoothly and complex deformation is avoided. In other words, the sloped portion is compressed and deformed from the center of the sloped portion in the same state on the board main body side and the flat side. , it is possible to avoid deviation and deformation of the slope portion, and prevent functional deterioration of the slope portion.

[Brief explanation of drawings]

Figures 1 to 5 show examples of this invention; Figure 1 is a partially cutaway plan view of a gasket for an internal combustion engine;
The figure is an enlarged sectional view of a gasket for an internal combustion engine taken along the - line in Figure 1, and Figure 3 is a diagram of a gasket for an internal combustion engine before being interposed and fastened between the deck surface of the cylinder head and the deck surface of the cylinder block. FIG. 4 is a partial cross-sectional view of a gasket for an internal combustion engine when it is compressed and deformed in a state where the substrate body and the third sub-plate are not in contact with each other, and FIG. 5 is a partial sectional view of the substrate body. FIG. 7 is a partial cross-sectional view of a gasket for an internal combustion engine when the gasket is compressively deformed and used in a state where the gasket and the third sub-plate are in contact with each other. In the figure, 1 is a substrate, 1b is a flat part, 1c is a main board part, 2 is a first sub-plate, 2a is an edge part of the first sub-plate, 2b is a peripheral part, 2c is a first sub-plate main part, 2 ′
is the second sub-plate, 2'b is the edge of the second sub-plate, 2'' is the third sub-plate
Sub-plate, 2"b is the third sub-plate edge, 2"c is the third sub-plate main body, a is the sloped part, 10 is the gasket for internal combustion engine, 13 is the opening, 14 is the first bent part , 15 is a second bent portion, 16 is a space, 20 is a bore hole, and S is a step distance between the first sub-plate main body and the first sub-plate edge.

Claims (1)

[Scope of utility model registration request] A substrate made of a hard metal plate has an opening of a predetermined size, a slope portion surrounding the opening, a substrate main body portion continuous to a first bent portion that is one end of the slope portion, and the other end of the slope portion. a first sub-plate formed of a soft metal plate having a lower hardness than the substrate and forming a flat portion that is continuous with the second bent portion and is substantially parallel to the substrate main body portion and located on the opening side; is provided in contact with the substrate body on one surface side of the substrate, and the slope portion and the flat portion are covered by a peripheral edge portion formed by folding back the first sub-plate on the opening side. The first sub-plate edge portion of the first sub-plate that is continuous with the peripheral edge portion is positioned substantially parallel to the first sub-plate main body portion of the first sub-plate that is in contact with the substrate main body portion, and the A flat portion is provided in contact with the first sub-plate edge, and the first sub-plate end face of the first sub-plate edge is connected to the first sub-plate, which is a continuous portion of the substrate main body and the sloped portion. Provided at a position slightly closer to the board main body than the position of the bent part, and located on the other side of the board at substantially the same position as the edge of the first sub-plate and substantially parallel to the board main body. A second sub-plate made of a soft metal plate having a second sub-plate main body portion is provided, and an end edge of the second sub-plate on the opening side is bent at a step portion to form the second sub-plate. The first sub-plate end edge is provided so as to overlap the substrate side surface, and the second sub-plate end face of the second sub-plate end edge is provided at approximately the same position as the first bent part, and the slope a third sub-plate is provided in contact with the second sub-plate main body within a space formed between the board main body and the second sub-plate;
The third sub-plate end surface of the third sub-plate end edge on the opening side that is continuous with the third sub-plate body part of the third sub-plate is not brought into contact with the step part of the second sub-plate. A gasket for an internal combustion engine, characterized in that the gaskets are spaced apart.