JP6529001B1 - Cylinder head gasket - Google Patents

Abstract

An object of the present invention is to provide a cylinder head gasket which enables efficient cooling of a cylinder bore wall without closing a cooling water hole. A cylinder block (20) and a cylinder head (10) are interposed between a cylinder block (20) and a cylinder head (10) of an engine having a plurality of cylinder bores and adjacent to a cylinder bore wall (22) between adjacent cylinder bores in the arrangement direction. And at least one cooling water hole 33 for circulating the cooling water between the cooling water holes, the cooling water holes being at least orthogonal to the arrangement direction (x direction) A plurality of inflow holes 33d1 and 33d2 spaced apart and opening on one surface of the cylinder head gasket 30, and a single outflow hole 33a in which the plurality of inflow holes merge and are open on the other surface of the cylinder head gasket 30 . [Selected figure] Figure 5

Description

  The present invention relates to a cylinder head gasket, and more particularly to a cylinder head gasket having a cooling water hole through which engine cooling water passes.

  Conventionally, a cylinder head gasket is interposed between the cylinder block and the cylinder head. A water jacket is formed around the plurality of cylinder bores provided in the cylinder block, to which cooling water is pumped from the water pump. The water jacket cooling water flows into the water jacket in the cylinder head through a plurality of cooling water holes formed in the cylinder head gasket, and is further delivered to a heat exchanger (radiator) outside the engine.

  Adjacent cylinder bores are separated by cylinder bore walls. Because the adjacent cylinder bores are closely spaced, the cylinder bore wall is relatively thin. Therefore, no water jacket is formed in the cylinder bore wall, and the cylinder bore is likely to get hot during engine operation. Therefore, it is necessary to cool the cylinder bore wall efficiently.

  A water jacket spacer may be disposed within the water jacket to direct the flow of cooling water to the cylinder bore wall to improve cooling efficiency. However, the water jacket spacer has a problem of high cost. So, for example, in patent document 1, the shape of the cooling water hole of a cylinder head gasket is changed. That is, in Patent Document 1, in the cooling water hole formed in a portion close to the cylinder bore wall, a projecting portion protruding toward the cylinder bore wall side is provided at a portion far from the cylinder bore wall in plan view. In patent document 1, it is going to concentrate the flow of the cooling water which passes a cooling water hole on the cylinder bore wall side by this protrusion part.

JP, 2015-194186, A

  However, the cylinder block and the cylinder head are cast products of, for example, aluminum alloy and have dimensional errors. For this reason, if a projection is provided in the coolant hole as in Patent Document 1 to reduce the opening area of the coolant hole, the coolant hole may be clogged. Furthermore, although it is effective to arrange the cooling water hole as close to the cylinder bore wall as possible in order to achieve high cooling efficiency, it is necessary to reduce the opening area of the cooling water hole, so the cooling water hole is blocked. There is a risk of

  The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a cylinder head gasket which enables efficient cooling of a cylinder bore wall without closing a cooling water hole.

In order to achieve the above object, the present invention is directed to a cylinder interposed between a cylinder block and a cylinder head of an engine having a plurality of cylinder bores, through a portion close to a cylinder bore wall between adjacent cylinder bores in the arrangement direction. A cylinder head gasket having one or more cooling water holes formed therein for circulating cooling water between a block and a cylinder head, wherein each cooling water hole has a plurality of inflow holes and one outflow hole. a plurality of inlet holes of the cooling water holes, open to one side of the cylinder head gasket at a distance from each other in a direction orthogonal to at least the arrangement direction, one outlet hole of the coolant hole, a plurality of inlet holes Join together and open on the other side of the cylinder head gasket.

  According to the present invention configured as described above, in the gasket, the cooling water hole is formed in the portion close to the cylinder bore wall. Engine cooling water flows in from a plurality of inflow holes of the cooling water holes formed on one side (inflow side) of the gasket, merges in the gasket, and is formed on the other side (outflow side) It flows out of one outlet hole of the hole. The plurality of inflow holes are spaced at least in the orthogonal direction in which the cylinder bore wall extends, and provide two orthogonally spaced cooling water flows passing through the inflow holes. Among them, the cooling water flow on the cylinder bore wall side promotes the flow in a region closer to the cylinder bore wall, so that the cylinder bore wall can be cooled more efficiently.

  As described above, in the present invention, by devising the shape of the cooling water hole provided in the gasket, the cooling water flow is prevented from flowing in the cylinder bore wall which is a high temperature region during operation of the engine without using additional parts such as a water jacket spacer. Can be cooled more efficiently. Also, even if the inflow holes on the cylinder bore wall side are completely blocked by the cylinder head or cylinder block due to dimensional error, the cooling water flow passing at least the other inflow holes is maintained, so the cooling function is It will not be completely lost. Furthermore, if at least a part of the inflow hole on the cylinder bore wall side is not shielded, the inflow hole on the cylinder bore wall side and the outflow hole are communicated via the junction hole of the gasket unless the outflow hole is completely closed. Therefore, the cooling water flow can be maintained.

In the present invention, preferably, the cylinder head gasket is formed by laminating a plurality of gasket members.
According to the present invention configured as described above, the cooling water holes can be easily formed by appropriately forming the inflow holes, the merging holes, and the outflow holes in the plurality of gasket members.

Specifically, the plurality of inflow holes of each cooling water hole is formed in a first gasket member forming at least one surface of the cylinder head gasket among the plurality of gasket members, and one in each cooling water hole The outflow hole is formed in a second gasket member that forms at least the other surface of the cylinder head gasket among the plurality of gasket members.

More specifically, the plurality of gasket members include a third gasket member disposed between the first gasket member and the second gasket member, and the third gasket member includes each cooling water hole A confluence hole is formed in which a plurality of inflow holes merge, and the confluence hole communicates with one outflow hole of each cooling water hole .

In the present invention, preferably, in the plurality of inflow holes of each cooling water hole, the flow rate of the cooling water passing through each inflow hole is set by the opening area of each inflow hole.
According to the present invention configured as described above, it is possible to set a flow ratio of the coolant flow passing closer to the cylinder bore wall and the coolant flow passing further away. For example, the cooling effect on the cylinder bore wall can be enhanced by setting a large flow rate of the cooling water flow close to the cylinder bore wall.

  According to the cylinder head gasket of the present invention, efficient cooling of the cylinder bore wall can be enabled without closing the cooling water hole.

1 is an exploded perspective view of an engine according to an embodiment of the present invention. It is a cross-sectional view of the engine corresponding to the II-II line of FIG. FIG. 5 is a plan view of a gasket according to an embodiment of the present invention. FIG. 5 is a bottom view of a gasket according to an embodiment of the present invention. It is an enlarged view of the area | region A of FIG. FIG. 4 is an enlarged view of a cooling water hole of a gasket according to an embodiment of the present invention. FIG. 6 is a cross-sectional view of a first modified gasket according to an embodiment of the present invention. It is an enlarged view of the cooling water hole of the gasket of the 1st modification according to the embodiment of the present invention. FIG. 7 is a cross-sectional view of a second modified gasket according to an embodiment of the present invention. It is an enlarged view of the cooling water hole of the gasket of the 2nd modification according to the embodiment of the present invention. It is an enlarged view of the cooling water hole of the gasket of the 3rd modification by embodiment of this invention. FIG. 10 is an enlarged view of a cooling water hole of a fourth modified gasket according to an embodiment of the present invention.

  Hereinafter, a cylinder head gasket (hereinafter referred to as "gasket") according to an embodiment of the present invention will be described with reference to the attached drawings. First, the basic configuration of the engine will be described with reference to FIGS. 1 to 4. 1 is an exploded perspective view of the engine, FIG. 2 is a cross-sectional view of the engine corresponding to line II-II in FIG. 1, FIG. 3 is a plan view of the gasket, and FIG. 4 is a bottom view of the gasket.

  As shown in FIG. 1, the engine 1 of the vehicle is a multi-cylinder engine (in this example, a four-cylinder engine), and an aluminum alloy cylinder head 10 and a cylinder block 20 are It intervenes and is integrally formed. In addition, various structures and accessories are attached to them.

  In the cylinder block 20, four cylinder bores 21 are arranged in a line in the vehicle width direction (y direction). Each cylinder bore 21 is substantially circular in plan view, and is formed to extend in the vertical direction. Adjacent cylinder bores 21, 21 are separated by a cylinder bore wall 22. A water jacket 23 is formed around the four cylinder bores 21 and the three cylinder bore walls 22 and is open to the upper surface of the cylinder block 20. Further, in the cylinder block 20, screw holes 24 are formed around the cylinder bores 21. The cylinder head 10 is attached to the cylinder block 20 by bolts 3 (see FIG. 2) using screw holes 24.

  The cylinder head 10 is formed with four recesses 11 that form the upper part of the combustion chamber corresponding to the four cylinder bores 21. In addition, a water jacket 13 (see FIG. 2) communicating with the water jacket 23 of the cylinder block 20 is formed around the recess 11.

  FIG. 3 and FIG. 4 show the outflow surface and the inflow surface of the gasket 30, respectively. That is, the cooling water passes the gasket 30 from the inflow side to the outflow side. As shown in FIGS. 3 and 4, the gasket 30 has four bores 31, four cooling water holes 32, six cooling water holes 33, and ten screws in alignment with the openings of the cylinder bores 21. Holes 34 are formed. The cooling water holes 32 and 33 connect the cylinder block 20 with the water jacket 23 and the water jacket 13 of the cylinder head 10. The cooling water hole 32 is provided on the exhaust side of the engine 1. The cooling water hole 33 is formed to be close to the side (the vehicle longitudinal direction; x direction) of the cylinder bore wall 22 which divides the adjacent cylinder bores 21.

  As shown in FIG. 2, in the cylinder block 20, water jackets 23 are formed on both sides of the cylinder bore wall 22. Further, a water jacket 13 is formed on the cylinder head 10. The cooling water 4 in the water jacket 23 of the cylinder block 20 flows into the water jacket 13 of the cylinder head 10 through the cooling water holes 32 and 33 of the gasket 30.

The gasket will now be described in detail with reference to FIGS. 5 and 6. FIG. 5 is an enlarged view of area A of FIG. 2, and FIG. 6 is an enlarged view of a cooling water hole.
As shown in FIG. 5, the gasket 30 is configured by laminating four gasket members (for example, stainless steel plates). The gasket 30 includes, in order from the top, a first gasket member 30a, a second gasket member 30b, a third gasket member 30c, and a fourth gasket member 30d. In the present embodiment, the first gasket member 30a and the fourth gasket member 30d have a thickness of 0.2 mm, and the second gasket member 30b and the third gasket member 30c have a thickness of 0.1 mm.

  As can be seen from FIG. 6, the cooling water holes 33 are oval in plan view. The first gasket member 30a is formed with an outflow hole 33a which is an oblong through hole. Similarly, in the second gasket member 30b and the third gasket member 30c, merging holes 33b and 33c having the same shape as the outflow hole 33a are respectively formed. Furthermore, the fourth gasket member 30d is formed with inflow holes 33d1 and 33d2, which are two through holes having the same diameter. In the outflow hole 33a in plan view, a portion between the two inflow holes 33d1 and 33d2 corresponds to the shielding portion 30e. The inflow holes 33d1 and 33d2 are separated at least in the x direction. In the present embodiment, the inflow holes 33d1 and 33d2 are disposed along the x direction (that is, symmetrically with respect to the adjacent cylinder bores 21), but the invention is not limited to this and may be disposed asymmetrically.

  As shown in FIG. 5, the cooling water flow f1 from the water jacket 23 of the cylinder block 20 flows into the cooling water hole 33 from the inflow hole 33d1. Further, the cooling water flow f2 flows into the cooling water holes 33 from the inflow holes 33d2. The cooling water flows f1 and f2 join at the merging holes 33b and 33c in the cooling water hole 33, and flow into the water jacket 13 of the cylinder head 10 through the outflow holes 33c communicating with the merging holes 33b and 33c. In addition, when the direction of a cooling water flow is reverse direction in FIG. 5, arrangement | positioning of an inflow hole and an outflow hole will also become reverse in an up-down direction.

  In the present embodiment, the cooling water moving upward in the water jacket 23 of the cylinder block 20 branches into the cooling water flow f1 and the cooling water flow f2 as it approaches the gasket 30. That is, in the present embodiment, by providing the inflow holes 33d2 that form the sub-passage separately from the inflow holes 33d1 that form the main passageway, cooling that passes through the area B (see FIG. 5) adjacent to the cylinder bore wall 22 Water flow f2 can be generated. Thereby, the cylinder bore wall which is a high temperature area at the time of operation of engine 1 can be cooled effectively.

  In the present embodiment, the inflow holes 33d1 are formed near the center of the water jackets 23, 13 in the longitudinal direction of the vehicle in consideration of dimensional errors of the cylinder block 20 and the cylinder head 10. That is, regardless of the dimensional error, the inflow hole 33d1 can secure an opening area for passing the cooling water without being blocked by the cylinder block 20 or the cylinder head 10.

  On the other hand, the inflow hole 33d2 is formed at a position closer to the cylinder bore wall 22 in the vehicle longitudinal direction than the inflow hole 33d1. The inflow hole 33 d 2 is also formed at a position not blocked by the cylinder block 20 or the cylinder head 10 in consideration of the dimensional error. However, even if the inflow holes 33d2 are partially or completely blocked, at least the cooling water flow f1 is secured by the inflow holes 33d1.

  Furthermore, the cooling water holes 33 have a plurality of inflow holes 33d1 and 33d2, but these join together at the merging holes 33b and 33c on the way, and have only one outflow hole 33a. Therefore, even if the upper portion of the inflow hole 33d2 is completely blocked by the cylinder head 10, the cooling water flow f2 passing through the inflow hole 33d2 is not restricted unless the lower portion of the inflow hole 33d2 is completely blocked by the cylinder block 20. , And can flow out of the outflow hole 33a through the merging holes 33b and 33c. Therefore, in comparison with a configuration in which a plurality of cooling water holes having a single inflow hole and a single outflow hole are formed adjacent to each other, the cooling water hole 33 of this embodiment is a cooling water flow near the cylinder bore wall 22 Easy to secure.

  Next, modifications of the gasket will be described with reference to FIGS. 7 to 12. 7 and 8 are a cross-sectional view of the gasket of the first modification and an enlarged view of the cooling water hole, respectively. 9 and 10 are a cross-sectional view of the gasket of the second modification and an enlarged view of the cooling water hole, respectively. 11 and 12 are enlarged views of cooling water holes of the gaskets of the third and fourth modified examples, respectively. In the following, portions different from the embodiment of FIGS. 5 and 6 will be mainly described, and overlapping descriptions will be omitted.

  In the first modification of FIGS. 7 and 8, the cooling water hole 133 adjacent to the cylinder bore wall 22 is formed in the gasket 30. In this modification, the cooling water hole 133 has an inflow hole 133d1 which is a main passage and an inflow hole 133d2 which is a sub passage, and has one outflow hole 133a. The inflow holes 133d1 and 133d2 are in communication with the outflow hole 133a by the merging holes 133b and 133c.

  The inflow holes 133d1 and 133d2 have different opening areas (diameters). Specifically, the inflow hole 133 d 2 formed at a position close to the cylinder bore wall 22 is set to have a smaller opening area than the inflow hole 133 d 1 which is the main passage. Therefore, the shielding part 130e is substantially trapezoidal in a plan view. In this modification, this enables the inflow hole 133d2 to be formed at a position closer to the cylinder bore wall 22 than in the example of FIG.

  Further, the inflow hole 133d1 is formed near the center of the water jacket 23 in the front-rear direction of the vehicle and has a large opening area, so the cooling water flow f1 is larger than the cooling water flow f2 (f1> f2). That is, in this modification, the flow rate of the cooling water flow f2 with respect to the cooling water flow f1 (or the total flow rate) is set by setting the opening area ratio of the inflow holes 133d1 and the inflow holes 133d2 to a predetermined ratio.

  Unlike the first modified example, the second modified example of FIGS. 9 and 10 is an example in which the inflow hole closer to the cylinder bore wall 22 has a larger opening area than the far inflow hole. In this modification, the cooling water hole 233 adjacent to the cylinder bore wall 22 has an inflow hole 233d1 and an inflow hole 233d2, and has one outflow hole 233a. The inflow holes 233 d 1 and 233 d 2 are in communication with the outflow hole 233 a by the merging holes 233 b and 233 c.

  The inflow holes 233d1 and 233d2 have different opening areas (diameters). Specifically, the inflow hole 233 d 2 formed at a position close to the cylinder bore wall 22 is set to have a larger opening area than the inflow hole 233 d 1 formed at a far position. Therefore, the shielding part 230e is substantially trapezoidal in a plan view. In this modification, this makes it possible to hold at least a part of the inflow hole 233d2 in a state where it is not shielded by the cylinder head 10 or the cylinder block 20.

  In this modification, the inflow hole 233d1 is formed near the center of the water jacket 23 in the vehicle longitudinal direction, but the opening area is smaller than the inflow hole 233d2. For this reason, the cooling water flow f2 becomes the main flow rather than the cooling water flow f1 (f2> f1). That is, in this modification, the flow rate of the cooling water flow f2 with respect to the cooling water flow f1 (or the total flow rate) is set large by setting the opening area ratio of the inflow hole 233d1 and the inflow hole 233d2 to a predetermined ratio.

  The third modification of FIG. 11 is an example in which the inflow hole closer to the cylinder bore wall 22 is formed in a substantially triangular shape instead of a circular shape in the embodiment shown in FIG. In this modification, the cooling water hole 333 adjacent to the cylinder bore wall 22 has an inflow hole 333d1 and an inflow hole 333d2, and has one outflow hole 333a. The inflow holes 333d1 and 333d2 are in communication with the outflow hole 333a by the merging holes 333b and 333c.

  The inflow holes 333 d 2 are circular as in the example of FIG. 6, but the inflow holes 333 d 2 are substantially triangular in shape having a top facing the cylinder bore wall 22. In this modification, this allows the inflow hole 333d2 to be closer to the cylinder bore wall 22 so that the cylinder bore wall 22 can be cooled efficiently.

  A fourth modification of FIG. 12 is an example in which the cooling water holes have three inflow holes and one outflow hole. In this modification, the cooling water holes 433 adjacent to the cylinder bore wall 22 have inflow holes 433d1, 433d2 and 4433d3 and one outflow hole 433a. The inflow holes 433 d 1 433 d 2 433 d 3 are in communication with the outflow hole 433 a by the merging holes 433 b 433 c.

  The inflow holes 433d3 can be set to have a smaller opening area than the inflow holes 433d1 and 433d2. In this modification, this allows the inflow hole 433 d 3 to be closer to the cylinder bore wall 22, so that the cylinder bore wall 22 can be cooled efficiently.

  In the fourth modification, the three inflow holes are arranged in series along the x direction. However, the present invention is not limited to this, and the three inflow holes may be arranged to be located at apexes of a triangle, respectively. .

The above embodiment and modifications may be further modified as follows.
In the above embodiment, the cooling water hole has a circular inflow hole, but the invention is not limited thereto, and the cooling water hole may have another shape (for example, a substantially triangular shape, an oval shape, a rectangular shape, or a polygonal shape).

  Moreover, in the said Example, although the confluence | merging hole is provided in the 2nd gasket member 30b and the 3rd gasket member 30c, not only this but for example, a confluence | merging hole is provided only in the 2nd gasket member 30b, A shielding part May be provided on the third gasket member 30c.

  Moreover, in the said Example, although the gasket 30 laminates | stacks the stainless steel plate of 4 sheets, it forms, not only this but it can laminate | stack and form the board | plate material of 2 or more sheets.

Next, the operation of the cylinder head gasket of the present embodiment will be described.
The present embodiment is interposed between the cylinder block 20 of the engine 1 having a plurality of cylinder bores 21 and the cylinder head 10, and passes through a portion close to the cylinder bore wall 22 between adjacent cylinder bores in the arrangement direction (y direction). A cylinder head gasket 30 in which one or more cooling water holes 33 (133, 233, 333, 433) for circulating the cooling water 4 between the cylinder block 20 and the cylinder head 10 is formed, and each cooling A plurality of inflow holes 33d1 and 33d2 spaced apart in at least an orthogonal direction (x direction) orthogonal to the arrangement direction y and opened in one surface of the cylinder head gasket 30, and a plurality of inflow holes merge And an outlet hole 33a opening on the other surface of the gasket 30.

  In the present embodiment configured as described above, the cooling water hole 33 is formed in the portion of the gasket 30 close to the cylinder bore wall 22. The cooling water 4 of the engine 1 flows in from the plurality of inflow holes 33d1 and 33d2 of the cooling water hole 33 formed in one surface (inflow surface) of the gasket 30, merges in the gasket 30, and the other surface It flows out from one outflow hole 33a of the cooling water hole 33 formed in (surface). The plurality of inflow holes 33d1 and 33d2 are spaced at least in the orthogonal direction in which the cylinder bore wall 22 extends, and generate two cooling water flows f1 and f2 separated in the orthogonal direction passing through the inflow holes. Among these, since the cooling water flow f2 on the cylinder bore wall side promotes the flow in the region B (see FIG. 5) closer to the cylinder bore wall 22, the cylinder bore wall 22 can be cooled more efficiently.

  Thus, in the present embodiment, by devising the shape of the cooling water hole 33 provided in the gasket 30, a cylinder bore which is a high temperature region during operation of the engine 1 without using additional parts such as a water jacket spacer etc. The wall 22 can be efficiently cooled by the cooling water flow f2. Further, even if the inflow hole 33d2 on the cylinder bore wall side is completely blocked by the cylinder head 10 or the cylinder block 20 due to a dimensional error, the cooling water flow f1 passing through at least the other inflow hole 33d1 is maintained. Therefore, the cooling function is not completely lost. Furthermore, if at least a part of the inflow hole 33d2 is not shielded, the inflow hole on the cylinder bore wall side via the merging holes 33b and 33c of the gasket 30 unless the outflow hole 33a on the cylinder bore wall side is completely closed. Since 33 d 2 and the outflow hole 33 a are in communication, the cooling water flow f 2 can be maintained.

  Further, in the present embodiment, the cylinder head gasket 30 is formed by laminating a plurality of gasket members 30a to 30d. Thus, in the present embodiment, the cooling water holes 33 can be easily formed by appropriately forming the inflow holes, the merging holes, and the outflow holes in the plurality of gasket members.

  Further, in the present embodiment, the plurality of inflow holes 33d1 and 33d2 are formed in the first gasket member 30d that forms at least one surface (inflow surface) of the cylinder head gasket 30 among the plurality of gasket members. One outflow hole 33c is formed in the second gasket member 30a that forms at least the other surface (outflow surface) of the cylinder head gasket 30 among the plurality of gasket members. The first and second gasket members may each be composed of a plurality of plate members.

  Further, in the present embodiment, the plurality of gasket members include third gasket members 30b and 30c disposed between the first gasket member 30d and the second gasket member 30a, and the third gasket member is provided The junction holes 33b and 33c are formed by joining a plurality of inflow holes 33d1 and 33d2. The junction holes communicate with one outlet hole 33a. The third gasket member may be composed of a plurality of plate members.

  Further, in the present embodiment, the plurality of inflow holes 133d1, 133d2 (FIG. 8) and 233d1, 233d2 (FIG. 10) of the respective cooling water holes 133 (FIG. 8) and 233 (FIG. 10) have different opening areas. . Further, in the present embodiment, the flow rate of the cooling water passing through each inflow hole is set by the opening area of each inflow hole in the plurality of inflow holes. Thereby, in the present embodiment, it is possible to set the flow ratio of the cooling water flow f2 passing through the one closer to the cylinder bore wall 22 and the cooling water flow f1 passing through the farther one. For example, the cooling effect on the cylinder bore wall 22 can be enhanced by setting the flow rate of the cooling water flow f2 close to the cylinder bore wall large.

1 Engine 3 Bolt 4 Cooling Water 10 Cylinder Head 11 Recess 13 Water Jacket 20 Cylinder Block 22 Cylinder Bore 22 Cylinder Bore Wall 23 Water Jacket 24 Screw Hole 30 Cylinder Head Gasket 30a-30d Gasket Member 30e Shielding Portion 31 Bore Opening 32 Cooling Water Hole 33 Cooling Water hole 33a Outflow hole 33b, 33c Joint hole 33d1, 33d2 Inflow hole 34 Screw hole 130e, 230e, 330e, 430e1, 430e2 Shielding part 133, 233, 333, 433 Cooling water hole 133a, 233a, 333a, 433a Outflow hole 133b, 133c, 233b, 233c combined holes 333b, 333c, 433b, 433c combined holes 133d1, 133d2, 233d1, 233d2 inflow holes 333d1, 333d , 433d1,433d2,433d3 inflow hole f1, f2 cooling water flow

Claims (6)

A coolant is interposed between the cylinder block and the cylinder head through a portion which is interposed between a cylinder block and a cylinder head of an engine having a plurality of cylinder bores and which is adjacent to the cylinder bore wall between adjacent cylinder bores in the arrangement direction. A cylinder head gasket in which one or more cooling water holes for circulation are formed,
Each cooling water hole is provided with a plurality of inflow holes and one outflow hole,
Wherein the plurality of inlet holes of the cooling water hole, open on one side of at least the cylinder head gasket at a distance from each other in a perpendicular direction perpendicular to the arrangement direction,
The cylinder head gasket , wherein the one outlet hole of each of the cooling water holes is joined to the plurality of inlet holes and is opened to the other surface of the cylinder head gasket.   The cylinder head gasket according to claim 1, wherein the cylinder head gasket is formed by stacking a plurality of gasket members. The plurality of inflow holes of each of the cooling water holes are formed in a first gasket member forming at least one surface of the cylinder head gasket among the plurality of gasket members.
The said one outflow hole of each said cooling water hole is formed in the 2nd gasket member which forms the other side of the said cylinder head gasket at least among the said some gasket members. Cylinder head gasket. The plurality of gasket members includes a third gasket member disposed between the first gasket member and the second gasket member, and the third gasket member includes the plurality of the plurality of cooling water holes. The cylinder head gasket according to claim 3, wherein a confluence hole is formed in which the inflow holes congruent with each other, and the confluence hole is in communication with the one outflow hole of each of the cooling water holes .   The cylinder head gasket according to any one of claims 1 to 4, wherein the plurality of inflow holes of each of the cooling water holes have different opening areas. The cylinder head gasket according to claim 5, wherein the flow rate of the cooling water passing through each inflow hole is set by the opening area of each inflow hole of each of the plurality of inflow holes of each of the cooling water holes .