JP2001227410A - Cylinder head gasket for open deck engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cylinder head gasket for an open deck engine capable of completely preventing blow-by of combustion gas by effectively complementing tightening distortion around a cylinder bore of the open deck type multi-cylinder water-cooled engine. SOLUTION: In a stratified cylinder head gasket interposed between a cylinder block 3 and a cylinder head 6 in an open deck type multi-cylinder water- cooled engine, a stopper plate 10 of continuous ring shape corresponding to a shape of a deck surface 9a between each cylinder bore 5, 5... and a cooling water passage 4 is fixedly overlapped in a position enveloping each cylinder hole 12, 12... in a base board (lower side base board 17) in a lamination layer of the cylinder head gasket 1, an inner side bore bead 14 enveloping each cylinder hole and an outer side bore bead 15 continuously enveloping all the cylinder holes except between each cylinder hole through a flat part 7 in an external periphery of the inner side bore bead are formed in an overlapped part of the stopper plate 10 and the base board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a laminated type open-deck engine cylinder head gasket inserted between a cylinder block and a cylinder head of an open-deck multi-cylinder water-cooled engine.

[0002]

2. Description of the Related Art A conventional example of a metal cylinder head gasket inserted between a cylinder block and a cylinder head of an open deck type multi-cylinder water-cooled engine will be described.

[0003] The cylinder head gasket 5 shown in FIG.
0 denotes a cylinder bore 54 on the two metal substrates 57, 57.
Arc-shaped bead 56 formed so as to surround the
56 are stacked so that their tops face each other, and cooling water holes 50 a, 5 ′ are provided at positions corresponding to cooling water passages 55, 55 ′ provided in the cylinder head 52 and the cylinder block 51.
0b is formed, and bolt holes 58a, 58b are formed near the outer periphery of the respective substrates 57, 57. The cylinder head gasket 50 inserted between the cylinder head 52 and the cylinder block 51 is inserted into the bolt holes 58a, 58b. Fastening is performed by tightening the inserted bolt 53.

By the way, in such a gasket, when a combustion explosion occurs in the cylinder bore 54, the beads 56,
When 56 is hit between the mating surfaces of the cylinder block 51 and the cylinder head 52, the respective beads 56, 56 are bent, and the initial sealing effect is reduced due to aging, and the combustion gas blows through on the gasket surface. There was a disadvantage that it occurred.

[0005] In order to solve this drawback, a cylinder head gasket 60 shown in FIG. 14 has been proposed. The gasket 60 is formed by laminating a sub-plate 63 on a substrate 62 having a bead 61 having an arc-shaped cross section around the cylinder bore 54, and the grommet 6 surrounding the cylinder bore 54 is formed on the sub-plate 63.
4 has a configuration in which the cylinder hole 65 of the substrate 62 is sandwiched by folding back.

[0006] Such a cylinder head gasket 60
According to the grommet 64, a primary seal is formed,
Since the bead 61 forms a secondary seal, it can be expected that such a double sealing effect prevents the combustion gas from flowing over the gasket surface.

However, when expansion or contraction occurs due to a combustion explosion between the cylinder block 51 and the cylinder head 52, a phenomenon occurs in which the bead 61 bends and the substrate 62 moves to the cylinder bore 54 side. As a result of the inner end of the grommet 65 pressing on the inner circumference of the grommet 64, there is a disadvantage that the grommet 64 is cracked or damaged.

Further, in the aluminum cylinder block 51 in which the cylinder sleeve 67 made of cast iron is cast, since the formation part of the grommet 64 is located on the upper surface of the cylinder sleeve 67, the cylinder head gasket 60 is
If the combustion explosion occurs in the cylinder bore 54 in the state where the joint 3 is fastened, there is a problem that the grommet 64 exerts a concentrated load on the cylinder sleeve 67 so that the cylinder sleeve 67 is depressed or deformed.

Further, when the cylinder block 51 is made of aluminum and the cylinder block 51 is made of cast iron, the difference in the coefficient of thermal expansion between the cylinder block 67 and the cylinder block 51 on the outer periphery of the cylinder block 67 causes the difference between the two. There is a problem that a minute gap is formed, and the combustion gas passes through the gap through the gasket surface, and oil rises from the crank chamber side to the gasket surface.

On the other hand, an open deck type cylinder block 51 is provided with a cylinder bore 54 as shown in FIG.
A cooling water passage 55 is continuously provided around the cylinder head 51, and the cooling water passage 55 on the cylinder block 51 side is connected to the cylinder head 5.
The control of the flow rate of the cooling water to the cooling water passage 55 ′ on the second side is performed by adjusting the inner diameter of the cooling water hole 60 a of the substrate 62. It becomes an exposed configuration.

Therefore, in addition to the cooling water cavitation during the operation of the internal combustion engine, bubbles existing in the cooling water float and stay at the lower surface peripheral portion of the cooling water hole 60a of the substrate 62, resulting in an increase in temperature or cooling water. , And the rubber coating applied to the exposed portion on the upstream side of the substrate 62 is peeled off, thereby impairing the thermostat function and adversely affecting the cooling performance.

For this reason, conventionally, the rubber coating exposed on the lower peripheral portion of the cooling water hole 60a has been partially removed by a water jet or the like. There is a disadvantage that the above problem cannot be solved due to the occurrence of a residue.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to effectively replenish the tightening distortion around the cylinder bores of an open-deck multi-cylinder water-cooled engine so as to reduce the combustion gas. It is an object of the present invention to provide a cylinder head gasket for an open deck engine which can completely prevent blow-by of a cylinder.

The present invention also provides an open deck type multi-cylinder water-cooled engine that can completely prevent combustion gas from flowing through without applying a concentrated load to the upper surface of a cylinder sleeve cast inside the cylinder bore of the cylinder bore. An object of the present invention is to provide a cylinder head gasket for a deck engine.

Further, the present invention provides a cylinder head gasket for an open deck engine which can eliminate a peeling phenomenon of a rubber coating applied to a surface of a cylinder head gasket exposed in a cooling water passage of an open deck type multi-cylinder water-cooled engine. The purpose is to provide.

[0016]

According to the present invention, there is provided a cylinder head gasket for an open deck engine according to the present invention, in which a cooling water passage of a cylinder block in a multi-cylinder water-cooled engine is excluded except between cylinder bores. In a laminated cylinder head gasket inserted between a cylinder block and a cylinder head of an open deck type multi-cylinder water-cooled engine that continuously surrounds all cylinders, a deck surface between each of the cylinder bores and the cooling water passage A stopper plate having a continuous ring shape corresponding to the shape is fixedly overlapped at a position surrounding each cylinder hole in the substrate in which the cylinder head gasket is being laminated, and surrounds each cylinder hole at a portion where the stopper plate and the substrate overlap. Each cylinder via the inner bore and its outer flat Outer Boabido to continuously surround the entire cylinder bore except between, characterized in that has been formed.

According to a second aspect of the present invention, there is provided a cylinder head gasket for an open deck engine according to the first aspect, wherein the stopper plate is fixed to the substrate by bonding over the entire surface.

According to a third aspect of the present invention, in the cylinder head gasket for an open deck engine according to the first aspect, a projecting portion is formed at a required portion corresponding to a cooling water passage on an outer periphery of the stopper plate. The protrusion is blind-squeezed or burred for caulking and is caulked to a perforated portion formed in the substrate.

According to a fourth aspect of the present invention, in the cylinder head gasket for an open deck engine according to the first aspect of the present invention, a rubber coating for microseal is applied to the substrate surface on the cylinder block side in a range corresponding to the deck surface. The entire surface is coated between the substrate surface on the cylinder head side and the other laminated plates.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

In the cylinder head gasket 1 for an open deck engine according to the present invention, the cooling water passages 4 formed in the cylinder block 3 as shown in FIG. 2 are all cylinders except for between the cylinder bores 5 and 5 (portion indicated by 9). Are inserted between the cylinder block 3 and the cylinder head 6 (see FIG. 1) of the open deck type multi-cylinder water-cooled engine 2 which continuously surrounds It is fastened by a bolt 9 inserted into the bolt hole 8.

The cylinder head gasket 1 of the present invention inserted between the cylinder block 3 and the cylinder head 6 corresponds to the shape of the deck surface 9a between each of the cylinder bores 5, 5,. The continuous ring-shaped stopper plate 10 is fixed at a position surrounding the cylinder holes 12, 12... In the substrate (for example, the lower substrate 17) in which the cylinder head gasket is being laminated, and the stopper plate 10 and the substrate are overlapped. The inner boad 1 surrounding each cylinder hole 12, 12,.
4 and a flat portion 7 on the outer periphery of each cylinder hole 1.
The outer bore beads 15 are formed so as to continuously surround all the cylinder holes 12, 12, except for the area between 2, 12,.

Hereinafter, the cylinder head gasket according to the present invention will be described with reference to various embodiments.

(Embodiment 1) As shown in FIG. 1, a cylinder head gasket 1-1 of this embodiment comprises an upper substrate 16 which is a substrate on the cylinder head 6 side and a lower substrate 17 which is a substrate on the cylinder block 3 side. And a stopper plate 10 is fixedly provided on the upper surface of the lower substrate 17.

As shown in FIG. 2, the upper substrate 16 and the lower substrate 17 are formed with the same number of cylinder holes 12 as the number of the cylinder bores 5 formed in the cylinder block 3. Each of the cylinder holes 12, 12,. Cylinder block 3 on the outer circumference
A large number of cooling water holes 19 at a position corresponding to the cooling water passage 4
Are formed, each of the cooling water holes 19 has a throttle shape with an inner diameter for adjusting the flow rate of the cooling water, and an oil hole 20 and a bolt hole are provided at predetermined positions near the outer periphery of the cylinder head gasket 1-1. 24 are formed.

In this embodiment, the lower substrate 17 has a deck surface (hereinafter, referred to as a "deck surface 9 around each cylinder bore") between each of the cylinder bores 5, 5,.
a)), an outer bore 15 is formed from the side closer to each cylinder hole 12 through an inner bore 14 and a flat portion 7 on the outer periphery thereof. The outer bore 15 has a shape that continuously surrounds all cylinders (all cylinder holes 12, 12,...) Except between the cylinder holes 12, 12,.

In such a configuration, as shown in FIG. 3, the deck surface 9 at the connecting portion between the adjacent cylinder bores 5, 5 is formed to have a narrow width.
The inner bore beads 14 on both sides are formed close to each other via the flat portion 7, and each of the cylinder bores 5, 5
.. (Cylinder holes 12, 12,...) Are individually surrounded by the inner bore beads 14 to form a primary seal, and all the cylinder holes 12, 12 except between the cylinder bores 5, 5 (cylinder holes 12, 12) are formed. Can be formed as a secondary seal by continuously surrounding...

As shown in FIG. 1, in the lower substrate 17 of the present embodiment, the inner boad 14 has a stepped shape rising to the outer peripheral side, and the outer boad 15 has a stepped shape lowered to the outer peripheral side. In the vicinity of the outer periphery of the side substrate 17, a deck surface 9b provided on the outer periphery of the cooling water passage 4 of the cylinder block 3
A step-shaped outer peripheral bead 22 which rises to the outer peripheral side within the range is formed. Further, a stopper plate 10 is overlapped on the upper surface of the lower substrate 17 at a position corresponding to the deck surface 9a around each of the cylinder bores 5, 5,.

The stopper plate 10 has a shape corresponding to the shape of the deck surface 9a of each of the cylinder bores 5, 5,... As shown in FIG.
Has a continuous ring shape in which a number of ring shapes equal to are connected. In this embodiment, the stopper plate 10 is connected to each of the cylinder holes 12 of the lower substrate 17,
12 are fixed to the upper surface position surrounding them, and as a fixing method, a method by full-surface bonding is adopted.

The upper substrate 16 is formed with the inner and outer cavities 14 and 15 at the same positions as the respective inner and outer cavities 14 and 15 of the lower substrate 17 and having symmetrical shapes. That is, the upper substrate 1
6 includes a deck surface 9a around each of the cylinder holes 12, 12,...
Step-shaped inner bore beat 1 that goes down to the outer peripheral side
4, a step-shaped outer bead 15 that rises to the outer peripheral side on the outer periphery thereof, and a step-shaped outer peripheral bead 22 that descends to the outer peripheral side near the outer periphery of the upper substrate 16 are formed.

The protrusion 23 of the upper substrate 16 and the protrusion 23 of the lower substrate 17 formed on the outer periphery of the mating surface of the cylinder block 3 and the cylinder head 6 are rivets 36.
Thus, the upper substrate 16 and the lower substrate 17 are fixed.

The cylinder head gasket 1-1 is covered with a sealing material. When the coating method is described together with the method of manufacturing the substrate, the upper substrate 16 is formed by punching a SUS hard steel plate having rubber coating on both surfaces into a gasket shape, or by punching a SUS hard steel plate into a gasket shape, It is formed by applying rubber coating on both sides.

The lower substrate 17 is made of SU which is coated on one side with a sealing material of SUS hard steel plate or rubber coating 25.
After punching the outer periphery of the gasket of the S hard steel plate, a portion corresponding to the cooling water passage 4 of the cylinder block 3 is defined as an uncoated surface 26 (see FIG. 1). Rubber coating 2 for micro-seal by screen printing on the lower surface of lower substrate 17 excluding holes 20 and bolt holes 24 etc.
8 and then vulcanizing, punching out each hole based on the outer peripheral shape, then forming the inner bore beads 14, the outer bore beads 15, and the outer peripheral beads 22 collectively, The stopper plate 10 is bonded around the cylinder holes 12, 12,.
The upper substrate 16 is laminated and connected.

According to the above-described forming method, a portion of the lower substrate 17 avoiding the cooling water flow path can be set as the non-coated surface 26 by partial coating by screen printing. It becomes easy to control the thickness. In addition, peeling of the sealing material in the flow of cooling water is prevented, and it is possible to eliminate an increase in man-hours and residue in removing the sealing material by a water jet or the like. It can be handled.

The thus formed cylinder head gasket is composed of a stopper plate 10 fixed on the lower substrate 17 and an inner bore 1 formed on the overlapping portion 13.
4 and an outer bore bead 15 to form a double seal and coexist within a range of the deck surface 9a around each of the cylinder bores 5, 5,..., So that the combustion gas from each of the cylinder bores 5, 5,. It is possible to prevent double blow-through, and it is possible to maintain the balance between the load of the stopper plate 10 and the load of the outer bore 15 by setting the load of the inner bore 14 differently.

Therefore, the maximum load of the stopper plate 10 is, as shown in the load distribution of FIG. 1, the deck surface 9a around each of the cylinder bores 5, 5,.
Of the cylinder sleeve 30 cast on the inner periphery of each of the cylinder bores 5, 5,...

As shown in FIG. 1, the load of the inner bore 14 is applied to the upper surface of the cylinder sleeve 30 so that the cylinder sleeve 30 and the cylinder block 3
It is possible to prevent the passage of the combustion gas generated in the minute gap 31 with the outer peripheral surface of the cylinder and the rise of oil from the crank chamber.

In addition, in the above-mentioned forming method, after the stopper plate 10 is fixed on the lower substrate 17 by overlapping, the overlapping portion 13 is provided with the inner and outer beads 14 and 15.
The stopper plate 10 is formed integrally with the lower substrate 17 while being guided by the bead shape of the lower substrate 17, whereby the rigidity can be increased without impairing the stopper load. In addition, the stopper plate 10 can be kept at a fixed position even when a deviation occurs due to a difference in thermal expansion due to a difference in material.

(Embodiment 2) In FIG. 4, a common point between a cylinder head gasket 1-2 of this embodiment and a gasket 1-1 of Embodiment 1 is that an upper substrate 16 and a lower substrate 17 are laminated. In addition, a stopper plate 10 is fixed on the upper surface of the lower substrate 17 by bonding the whole surface, and the lower substrate 17 and the stopper are formed on the deck surface 9a of each of the cylinder bores 5, 5,. The plate 10 is superimposed, the inner bead 14 and the outer bead 15 are formed on the upper and lower substrates 17 and the outer bead 22 are formed on the upper and lower substrates 17 within the range of the superimposed portion 13, and the position and formation of the coating are formed. The method is common.

However, the gasket 1-2 of this embodiment is different from the gasket 1-1 of the first embodiment in the shape of beads formed on the upper substrate 16 and the lower substrate 17. That is, in the gasket 1-2 of this embodiment, the inner bore 14 is formed in an arc shape in which the lower substrate 17 side protrudes toward the cylinder head 6 side, and is mutually symmetrical with the inner bore 14 of the upper substrate 16 formed symmetrically. The outer bead 15 has a stepped shape in which the lower substrate 17 side rises to the outer peripheral side, the outer boad 15 of the upper substrate 16 is formed in a symmetrical shape with this, and the outer bead 15 of the lower substrate 17 Numeral 22 is formed in a stepped shape descending to the outer peripheral side, and is separated from the outer peripheral bead 22 of the upper substrate 16 formed symmetrically with the outer substrate 22. Are in contact with each other.

(Embodiment 3) As shown in FIG. 5, a cylinder head gasket 1-3 of this embodiment is formed by laminating an upper substrate 16, an intermediate substrate 18, and a lower substrate 17, which are three substrates. The upper substrate 16 has a shape in which the upper substrate 16 of the cylinder head gasket 1-1 of the first embodiment is turned upside down, and the lower substrate 17 has the same shape as the lower substrate 17 of the first embodiment. The inner bore 14 and the outer bore 15 formed on the upper substrate 16 and the lower substrate 17 are formed at symmetrical positions on the deck surface 9a of the cylinder bores 5, 5,.
6 and 17 both have a stepped shape which rises to the outer peripheral side, the outer bore bead 15 has a stepped shape which descends to the outer peripheral side of both the upper and lower substrates 16 and 17, and the outer peripheral bead 22 further has a stepped shape which extends to the upper and lower substrates 1.
Both 6 and 17 are formed so as to have a stepped shape rising to the outer peripheral side.

In this embodiment, a continuous ring-shaped stopper plate 10 is provided between the upper and lower substrates 16 and 17.
Are interposed and an intermediate substrate 18 is superimposed and fixed. Each cylinder bore 5, 5
The stopper plate 10 is entirely fixed by bonding in the area corresponding to the surrounding deck surface 9a, and the stepped portion is formed in the overlapping portion 13 so as to be stepped down from the cylinder holes 12, 12,. The upper and lower substrates 1 are provided with an outer bead 15 formed in a stepped shape rising to the outer peripheral side at the outer periphery thereof.
The inner and outer beads 14 and 15 are formed at the same position as the inner and outer beads 6 and 17, and the outer periphery thereof is flat without forming beads.

With the above configuration, the present embodiment can exert a higher bead load on the deck surface 9a around each of the cylinder bores 5, 5,... Than the gasket of the first or second embodiment. The structure in which the double seal formed by the outer bore 14 and the outer bore beat coexists within the range of the deck surface 9a around each cylinder bore 5, 5... Is the same, and the combustion gas blows out from each cylinder bore 5, 5. Can be prevented twice, and other effects are the same as those of the first embodiment.

Further, in the upper and lower substrates 16 and 17 of the cylinder head gasket 1-3 of this embodiment, the first embodiment is also applied.
The same coating is applied in the same positional relationship as described above, and the effect is the same as that of the first embodiment.

Further, in this embodiment, the stopper plate 10 is fixed on the lower surface of the intermediate substrate 18 by superimposition. However, the lower substrate 17 is laminated below the stopper plate 10, so that the stopper plate 10 Surface 9a
Is protected by the lower substrate 17 without contacting the lower substrate 1 and is in contact with the upper surface coating 25 of the lower substrate 17.
Even when a lateral load is applied to the stopper 7, the stopper plate 10 can be kept in a fixed position by the overall adhesive force to the intermediate substrate 18 and the guards formed by the bead shapes of the inner and outer beads 14 and 15. it can.

(Embodiment 4) A cylinder head gasket 1-4 of this embodiment is formed by laminating an upper substrate 16, an intermediate substrate 18, and a lower substrate 17, which are three substrates, as shown in FIG. The upper substrate 16 has the same shape as the upper substrate 16 of the cylinder head gasket 1-2 of the second embodiment,
Since the lower substrate 17 has a shape in which the lower substrate 17 of the second embodiment is turned upside down, both the inner board 14 formed on the upper substrate 16 and the lower substrate 17 of the present embodiment are on the cylinder block 3 side. The outer bead 15 has a stepped shape in which both the upper and lower substrates 16 and 17 are lowered toward the outer peripheral side.
Both 6 and 17 are formed so as to have a stepped shape rising to the outer peripheral side.

In this embodiment, a continuous ring-shaped stopper plate 1 is provided between the upper and lower substrates 16 and 17.
An intermediate substrate 18 having the “0” fixed thereon is inserted. On the lower surface of the intermediate substrate 18, a stopper plate 10 is fixed on the deck surface 9a around each of the cylinder bores 5, 5,. At the same position, an inner bore 14 protruding toward the cylinder head 6 side and having an arc-shaped cross section and an outer bore 15 having a stepped shape rising to the outer circumference at the outer circumference are formed, and no bead is formed at the outer circumference thereafter. Has been.

With the above configuration, the cylinder head gasket 1-4 of the present embodiment exerts a higher bead load on the deck surface 9a around each of the cylinder bores 5, 5,... Than the gasket of the first or second embodiment. The structure in which a double seal formed by the inner bore beads 14 and the outer bore beats coexist within the range of the deck surface 9a around each cylinder bore 5, 5,... Is the same, and the combustion gas from each cylinder bore 5, 5,. Can be prevented twice, and the other effects are the same as those of the first embodiment.

The first and second substrates 16 and 17 of the cylinder head gasket 1-4 of this embodiment are also used in the first embodiment.
The same coating is applied in the same positional relationship as described above, and the effect is the same as that of the first embodiment.

Further, in this embodiment, the stopper plate 10 is fixed on the lower surface of the intermediate substrate 18 by stacking. However, since the lower substrate 17 is further laminated thereunder, the stopper plate 10 Since the lower substrate 17 is protected by the lower substrate 17 without contacting the deck surface 9a and is in contact with the upper surface coating 25 of the lower substrate 17, even when a lateral load is applied to the lower substrate 17, the stopper plate is provided. Numeral 10 can be kept fixed at a fixed position by the overall adhesive force to the intermediate substrate 18 and the guard of the inner and outer beads 14 and 15 by the bead shape.

(Embodiment 5) The cylinder head gasket 1-5 of this embodiment is different from the cylinder head gasket 1-2 of Embodiment 2 in that the stopper plate 10 of the cylinder head gasket 1-2 is fixed on the surface of the lower substrate 17 by bonding over the entire surface. And a blind stop 33 for caulking.

For this purpose, the continuous ring-shaped stopper plate 10 is formed with a projecting portion 32 at a required portion (see FIG. 8) corresponding to the cooling water passage 4 on the outer periphery thereof. The stopper plate 10 has a structure in which the stopper plate 10 is caulked and connected to a perforated portion 34 formed in the lower substrate 17 so that the stopper plate 10 can be more firmly fixed in a fixed position. Other configurations are the same as those of the cylinder head gasket 1-2 of the second embodiment, and various effects are also the same.

(Embodiment 6) The cylinder head gasket 1-6 of this embodiment is caulked instead of fixing the stopper plate 10 of the gasket 1-4 of Embodiment 4 on the surface of the lower substrate 17 by whole surface bonding. A bulging portion 32 is formed at a required portion (see FIG. 8) corresponding to the cooling water passage 4 on the outer periphery of the continuous ring-shaped stopper plate 10. A burring 35 for caulking is applied to the lower substrate 17.
The stopper plate 10 can be more firmly fixed in place, and the lower substrate 17 can prevent the passage of cooling water. Other configurations are the same as those of the cylinder head gasket 1-4 of the fourth embodiment, and various effects are also the same.

(Comparative Example) A metal gasket 40 shown in FIGS. 10 to 12 has been devised as a technique of an application filed by the present inventor (Japanese Patent Application No. 8-218440). This metal gasket 40 is applied to an engine with a sub-combustion chamber such as a diesel engine. As shown in FIG. 12, two elastic substrates 41 and 42 are joined with rivets 43 and the inner surface of the lower substrate 41 is formed. A sub-plate 44 is adhered to the sub-plate 44, and the overlapping range of the sub-plate 44 extends from the periphery of the cylinder bore 5 to the inner periphery of the cooling water passage 4.

As shown in FIG. 12, double step beads 41a, 41b and 42 are provided around the cylinder bore 5.
a and 42b are provided and a flat surface 45 is provided between the two beads. Of these beads, the inner beads 41a and 42a surrounding the cylinder bore 5 apply a load to the hot plug 47 of the sub-combustion chamber 46. Position, the inner beads 41a, 42a
The hot plug 47 is depressed or deformed by the load.
In order to prevent this, the hot plug 47 of the sub-combustion chamber 46 is avoided on the outer periphery of the inner beads 41a and 42a, and a partial range similar to the forming range of the hot plug 47 (see FIGS. 10 and 11). Outer beads 41b, 42b
Forming an outer bead 41 closer to the bolt fastening position
A stronger load is applied to b and 42b, thereby reducing the load on the inner beads 41a and 42a to prevent the hot plug 47 from being depressed or deformed.

Therefore, as described above, the outer beads 41b,
Since the formation range of 42b is limited to the position near the hot plug 47 in the sub-combustion chamber 46, it does not continuously surround all the cylinder holes 12, 12,.
It should be clearly distinguished from the present invention.

[0057]

As described above, according to the cylinder head gasket for the open deck engine of the present invention, each cylinder hole is formed by the inner bore formed in the overlapped portion of the stopper plate fixedly attached to the substrate being laminated. The primary seal is performed, and all the cylinder holes are secondarily sealed by an outer bore bead that continuously surrounds all the cylinder holes except between the cylinder holes through a flat portion on the outer periphery thereof. It is possible to prevent double blow-through, and it is also possible to maintain the balance with the load by the stopper plate by adjusting the load of the outer and inner bore beads, and the cylinder sleeve cast on the inner circumference of the cylinder bore Since the concentrated load is not applied to the upper surface of the cylinder, It is possible to prevent the form.

Further, as described above, the double sealing of the inner bore and the outer bore prevents the passage of the combustion gas generated in the minute gap between the cylinder sleeve and the outer peripheral surface of the cylinder block and the rise of oil from the crank chamber. Becomes possible.

Further, the stopper plate is integrally held while being guided by the bead shape of the substrate, whereby the rigidity can be increased without impairing the stopper load, and the stopper plate is displaced due to a difference in thermal expansion due to a difference in material. Even when the occurrence of a wobble occurs, the stopper plate can be maintained at a fixed position.

Further, a portion of the substrate avoiding the cooling water flow path can be made a non-coated surface by partial coating with the micro-seal rubber coating, thereby preventing peeling of the sealing material in the flow of the cooling water. It is possible to eliminate an increase in the number of steps in removing the sealing material by a water jet or the like, and to eliminate a residue, and it is possible to avoid pollution problems and to perform an advantageous handling even in the reprocessing of a substrate.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a state in which a cylinder head gasket according to a first embodiment of the present invention is mounted on an open-deck multi-cylinder water-cooled engine, which corresponds to a cross-sectional position along the line AA in FIG. Things.

FIG. 2 is an exploded perspective view showing a state in which the cylinder head gasket according to the first embodiment of the present invention is mounted on an open deck type multi-cylinder water-cooled engine.

FIG. 3 is a partial perspective view showing a cross-sectional state along the line BB of FIG. 2;

FIG. 4 is a partial sectional view showing a state in which a cylinder head gasket according to a second embodiment of the present invention is mounted on an open deck type multi-cylinder water-cooled engine.

FIG. 5 is a partial sectional view of a cylinder head gasket according to a third embodiment of the present invention.

FIG. 6 is a partial sectional view of a cylinder head gasket according to a fourth embodiment of the present invention.

FIG. 7 is a partial cross-sectional view of a cylinder head gasket according to a fifth embodiment of the present invention, which corresponds to a cross-sectional position along the line CC in FIG.

FIG. 8 is an exploded perspective view showing a state in which a cylinder head gasket according to a fifth embodiment of the present invention is mounted on an open deck type multi-cylinder water-cooled engine.

FIG. 9 is a partial sectional view of a cylinder head gasket according to a sixth embodiment of the present invention.

FIG. 10 is a partial plan view of a conventional gasket showing a comparative example with the present invention.

11 is an enlarged view of a two-dot chain line D in FIG.

FIG. 12 is a partial cross-sectional view taken along line EE of FIG. 11;

FIG. 13 is a partial cross-sectional view showing a state in which a conventional gasket is mounted on an open deck type multi-cylinder water-cooled engine.

FIG. 14 is a partial cross-sectional view showing a state in which another conventional gasket is mounted on an open deck type multi-cylinder water-cooled engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 (1-1 to 1-6) ... Cylinder head gasket 2 ... Open deck type multi-cylinder water-cooled engine 3 ... Cylinder block 4 ... Cooling water passage 5 ... Cylinder bore 6 ... Cylinder head 9 ... Bolt 10 ... Stopper plate 12 ... Cylinder hole DESCRIPTION OF SYMBOLS 13 ... Overlapping part 14 ... Inner bead bead 15 ... Outer bead bead 16 ... Upper board 17 ... Lower board 19 ... Cooling water hole 20 ... Oil hole 24 ... Bolt hole 25 ... Rubber coating 26 ... Uncoated surface 28 ... Rubber coating for micro seal 32 ... overhang 33 ... blind aperture 35 ... burring

Claims (4)

[Claims] 1. A cooling water passage of a cylinder block in a multi-cylinder water-cooled engine is interposed between a cylinder block and a cylinder head of an open deck type multi-cylinder water-cooled engine which continuously surrounds all cylinders except between cylinder bores. In the stacked cylinder head gasket, a position where a continuous ring-shaped stopper plate corresponding to the deck surface shape between each of the cylinder bores and the cooling water passage surrounds each of the cylinder holes in the substrate on which the cylinder head gasket is being stacked. And an outer bead which continuously surrounds all the cylinder holes except between the cylinder holes via a flat portion on the outer periphery thereof and an inner bore bead surrounding each cylinder hole at the overlapped portion of the stopper plate and the substrate. Cylinder head for open deck engine characterized by forming Gasket. 2. The cylinder head gasket for an open deck engine according to claim 1, wherein said stopper plate is fixed to said substrate by whole surface bonding. 3. An overhang portion is formed at a required portion on the outer periphery of the stopper plate corresponding to a cooling water passage, and a blind hole or burring for caulking is applied to the overhang portion to form a perforated portion formed on the substrate. The cylinder head gasket for an open deck engine according to claim 1, wherein the gasket is caulked. 4. A micro-seal rubber coating is applied to the substrate surface on the cylinder block side in a range corresponding to the deck surface, and the entire coating is applied between the substrate surface on the cylinder head side and other laminated plates. The cylinder head gasket for an open deck engine according to claim 1, wherein: