JP2004218526A - Metallic gasket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metallic gasket capable of securing a stable sealing performance at a low cost and for a long period of time even if a vibration is applied thereto when the engine is working. <P>SOLUTION: A first thickened part 7 and an inner periphery side bead BD1 are formed around each combustion chamber hole 3, an outer periphery side bead BD2 is formed along the outer periphery of a substrate 2, and third thickened parts 10 are formed at the outer periphery side of the outer periphery side bead BD2. In addition, a second thickened part 20 is formed between the inner periphery side beads BD1 and the outer periphery side bead BD2. A spring element is added to each first thickened part 7. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a metal gasket which is inserted between a cylinder block and a cylinder head of an internal combustion engine and fastened by bolts to seal combustion gas, water pressure and oil pressure.
[0002]
[Prior art]
Conventionally, as this type of metal gasket, for example, there is a metal gasket as shown in FIGS. 16 and 17 (see Patent Document 1).
The metal gasket is thickened by inserting a sub-plate 51 having high rigidity between the two substrates 50 stacked and folding the end of the sub-plate 51 on the combustion chamber side to form the thickened portion 52. When formed and the metal gasket is assembled to the engine, the maximum load is applied to the thickened portion 52 to seal the high-pressure gas in the combustion chamber.
[0003]
Further, metal beads 53 are formed on the two substrates 50 at positions surrounding the combustion chamber holes. The beads 53 are formed by bending the substrate 50 in a convex shape toward the sub-plate 51 side. The bead 53 is deformed up to the thickness of the thickened portion 52 and is sealed by metal contact, and the amount of compressive deformation is regulated by the thickened portion 52 so that the amount of compressive deformation of the bead is regulated. Limits the amplitude of vibration of the bead due to vibration during engine operation to prevent fatigue failure.
[0004]
[Patent Document 1]
JP-A-1-65367
[0005]
[Problems to be solved by the invention]
However, since the bead 53 exhibits a sealing function by metal contact, the substrate 50 on which the bead 53 is formed needs to be of high hardness. The internal stress concentrated in the part may be input by repeated compression and tension, leading to fatigue failure.
[0006]
Further, since the engine using the metal gasket tends to further reduce the weight, increase the in-cylinder pressure, increase the combustion gas temperature, and the like, the heat deformation and the vibration amplitude tend to increase, so that the hardness as described above is high. The base material has a limit in preventing fatigue fracture, and it is desirable to lower the hardness of the substrate 50.
However, in the above-described conventional metal gasket, when the hardness of the substrate 50 is reduced, the spring force for generating beads is reduced, and further, the deformation of the beads in the thickened portion is limited, so that the seal line width is also narrow. Therefore, it is susceptible to scratches on the sealing surface and cavities.
The present invention has been made in order to solve such inconvenience, and provides a metal gasket that can secure a low-cost and stable sealing performance for a long period of time even when vibrations occur during operation of an engine. The challenge is to do that.
[0007]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention relates to a substrate made of a thin metal plate having at least a combustion chamber hole opened so as to surround the combustion chamber hole in an endless annular shape. A metallic first thickened portion extending along the opening end of the combustion chamber hole and formed thicker than other portions, and the first thickened portion and the combustion at the outer periphery of the first thickened portion An inner peripheral bead surrounding the chamber hole in an endless annular shape; an outer peripheral bead extending along the outer peripheral portion of the substrate; and a thicker than the other portion disposed between the inner peripheral bead and the outer peripheral bead. A second thickened portion made of metal,
When the thickness of the first thickened portion is H1 and the thickness of the second thickened portion is H2, the relationship of H1> H2 is set;
The inner peripheral bead is formed by bending the substrate in the thickness direction to be convex on one surface side, the height of the convex portion being higher than the first thickened portion, and the convex portion side surface of the metal bead. And a rubber bead made of an elastic sealing material that is filled in the concave portion on the back side of the convex portion and is compressed and deformed in the plate thickness direction together with the deformation of the metal bead,
The outer peripheral side bead is formed by bending the substrate in the plate thickness direction to be convex on one surface side, and the convex portion height is higher than the second thickened portion, and the convex portion side surface of the metal bead. A metal gasket comprising a combination of a rubber bead made of an elastic sealing material which is fixed and filled in a concave portion on the back side of the convex portion and is compressed and deformed in the thickness direction together with the deformation of the metal bead. Things.
[0008]
According to the present invention, each bead is formed by synthesizing a metal bead and a rubber bead, and the soft elastic sealing material comes into contact with the joint surface, thereby lowering the hardness of the substrate and ensuring reliable sealing by the bead. Become.
In addition, due to the vibration caused by the operation of the engine, a pulsating repetitive load in the plate thickness direction is input to the metal gasket, and the substrate portion located between the inner bead and the outer bead vibrates in the plate thickness direction. However, in the present embodiment, by providing the second thickened portion, deformation of the substrate portion located between the inner bead and the outer bead is suppressed.
[0009]
Here, when the substrate portion located between the inner peripheral side bead and the outer peripheral side bead is repeatedly deformed in the thickness direction (deformed in the recessed direction), a load is repeatedly applied to the metal bead, and the metal bead is repetitively loaded. Not only adversely affects the service life, but also leads to fluctuations in sealing pressure due to beads.
Further, by forming the second thickened portion, the area of the thickened portion which is mainly subjected to surface pressure is increased, and even when the thickened portion is incorporated into an engine having a large fastening load such as a diesel engine, It is possible to prevent the first thickened portion surface from being dented beyond the proof stress. As a result, blow-through of gas from the combustion chamber holes can be more effectively prevented.
[0010]
Next, according to a second aspect of the present invention, in the configuration described in the first aspect, a metal layer formed on the substrate on the outer peripheral side with respect to the outer peripheral side bead so as to be thicker than other portions. A third thickening portion is provided, wherein the relationship of H1> H3 is set when the plate thickness of the third thickening portion is H3.
Next, according to a third aspect of the present invention, the first thickened portion is formed by folding the end of the combustion chamber hole side, with respect to the configuration described in the first or second aspect. A shim is interposed.
[0011]
By interposing the shim, it becomes easy to change the plate thickness along the circumferential direction in the first thickened portion where the surface pressure becomes highest. In addition, it is preferable to equalize the sealing pressure along the circumferential direction of the first thickened portion by giving the plate thickness along the circumferential direction of the first thickened portion. By equalizing, it is possible to improve the roundness of the bore.
Next, in the invention described in claim 4, the sub-plate stacked and arranged so as to face the substrate from the side of the convex portion of the bead with respect to the configuration described in any one of claims 1 to 3 is provided. A spring element capable of exerting a spring force in the plate thickness direction by bending the sub plate in the plate thickness direction is provided at a position of the sub plate facing the first thickened portion. It is characterized by the following.
[0012]
By adding a spring element to the first thickened portion, even if the surface pressure around the combustion chamber hole is out of balance due to thermal deformation or the like, the spring element follows the deformation, and the first thickened portion has Compensates for a partial decrease in surface pressure.
Next, according to a fifth aspect of the present invention, in addition to the configuration of the third aspect, the shim includes a spring element that is bent and formed in the plate thickness direction and can exert a spring force in the plate thickness direction. The metal gasket according to claim 2, wherein:
[0013]
By adding a spring element to the first thickened portion, even if the surface pressure around the combustion chamber hole is out of balance due to thermal deformation or the like, the spring element follows the deformation, and the first thickened portion has Compensates for a partial decrease in surface pressure.
Next, the invention described in claim 6 is characterized in that, in addition to the configuration described in claim 5, a sub-plate is arranged so as to be opposed to the substrate from the side of the convex portion of the bead. It is.
[0014]
The sub-plate protects the elastic sealing material on the convex side and adjusts the thickness of the metal gasket.
Next, a seventh aspect of the present invention provides the configuration according to any one of the first to sixth aspects, further comprising a sub-plate laminated on the substrate, and the first thickness increasing in the thickness direction. The present invention is characterized in that a spring element formed by bending and forming a sub-plate in a plate thickness direction is provided for a portion where a surface pressure change is likely to occur in a substrate including a portion opposed to a portion.
[0015]
Next, the invention according to claim 8 includes two substrates stacked and arranged, and a sub-plate interposed between the two substrates, and the two substrates and the sub-plate are each at least burned. It consists of a thin metal plate with an open chamber hole,
At least one of the two substrates and the sub-plate extends along the opening end of the combustion chamber hole so as to surround the combustion chamber hole in an endless annular shape, and is thicker than other portions. Forming a first thickened portion of metal,
Each of the two substrates is provided with an inner peripheral bead surrounding the combustion chamber hole endlessly at an outer peripheral position than the first thickened portion and an outer peripheral bead extending along the outer peripheral end of the substrate. ,
A metallic second thickened portion formed between the inner circumferential bead and the outer circumferential bead and formed thicker than other portions with respect to at least one of the two substrates and the sub plate. And
When the thickness of the first thickened portion is H1 and the thickness of the second thickened portion is H2, the relationship of H1> H2 is set;
The inner peripheral bead is formed by bending the substrate in the plate thickness direction to form a convex shape on the sub-plate side, the height of the convex portion being higher than the first thickened portion, and the convex portion side surface of the metal bead. And a rubber bead made of an elastic sealing material that is fixed and filled in the concave part on the back side of the convex part and is compressed and deformed in the thickness direction together with the deformation of the metal bead. The metal bead is bent in the direction and becomes convex on the sub-plate side, and the height of the convex portion is higher than the second thickened portion. The metal bead is fixed to the convex side surface of the metal bead and is filled in the concave portion on the back side of the convex portion. And a rubber bead made of an elastic sealing material that is compressed and deformed in the thickness direction together with the deformation of the metal bead.
[0016]
The sub-plate exerts the above-described action while protecting the elastic sealing material on the convex portion side.
Next, according to a ninth aspect of the present invention, in addition to the configuration described in the eighth aspect, at least one of the two substrates and the sub-plate is provided on the outer peripheral side with respect to the outer peripheral bead. When a third thickened portion that is thicker and more metallic than the portion is formed and the plate thickness of the third thickened portion is set to H3, the relationship of H1> H3 is set. .
[0017]
Next, a tenth aspect of the present invention is different from the eighth or ninth aspect in that, in the first thickening portion position, at least one of the sub-plate and the two substrates has a plate thickness. A metal spring element which is bent in the direction and can exert a spring force in the plate thickness direction is provided.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a first embodiment according to the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of a main part showing a metal gasket 1 according to the present embodiment, and FIG. 2 is a sectional view taken along line BB in FIG.
First, the configuration will be described.
[0019]
The substrate 2 is made of a thin metal plate such as a stainless steel plate or a mild steel plate. In the present embodiment, it is assumed that the substrate 2 is made of a mild steel plate for low-priced products. In the metal gasket of the present embodiment, even if a mild steel plate having a low hardness is used as described later, a sufficient seal using a bead is possible.
As shown in FIG. 1, a plurality of combustion chamber holes 3 are opened at a substantially central portion of the substrate 2. As shown in FIG. 2, the entire periphery of each combustion chamber side end is folded back, and a shim plate 11 is inserted in the folded-back portion 7 a to form a first thickened portion 7. The shim plate 11 is bent and formed so as to have a convex shape in the plate thickness direction and includes a metallic spring element 11a, thereby providing a spring to the first thickened portion 7.
[0020]
Further, an inner peripheral side seal line SL1 is set so as to surround each combustion chamber hole 3 and the first thickened portion 7, and an inner peripheral side bead BD1 is formed along the inner peripheral side seal line SL1.
Various holes 4, 5, and 6 such as a bolt hole 4, a water hole 5, and an oil hole 6 are formed on a portion of the substrate 2 located on the outer peripheral side of the inner peripheral side seal line SL1 with the joining surface (cylinder block, cylinder head, etc.). (Sealing surface). An outer peripheral seal line SL2 is set along the outer peripheral portion of the substrate 2 at a position on the outer peripheral side of the various holes 4, 5, and 6, and an outer peripheral bead BD2 is formed along the outer peripheral seal line SL2. . Further, a third seal line SL3 is set so as to surround each water hole 5, and the third bead BD3 is formed. In addition, at the position where the seal lines merge, various beads are merged to form one bead.
[0021]
Further, a third thickened portion 10 is formed at an outer end position which is a position on the outer peripheral side of the outer peripheral side seal line SL2 by folding back the outer end side of the substrate. A shim 12 is inserted in the folded portion for thickness adjustment.
As shown in FIG. 2, each of the beads BD1 and BD2 described above is configured to exert a spring force by combining metal beads 13 and 16 made of full beads and rubber beads. The second bead BD3 (not shown) has the same configuration.
[0022]
The metal beads 13 and 16 are formed by bending the substrate 2 in the thickness direction so as to be convex on the folded side (upper surface side) of the first thickened portion 7.
Further, the rubber beads are composed of first elastic sealing materials 14 and 17 filled in the concave portions of the metal beads 13 and 16 and a second elastic sealing material 15 fixed to the convex portions of the metal beads 13 and 16. , And 18.
[0023]
The first elastic sealing members 14 and 17 are set so that the surface thereof is substantially flush with the lower surface of the substrate 2. In addition, it is preferable to form one or a plurality of downwardly projecting protrusions at substantially the center of the first elastic seal members 14 and 17 in the bead width direction so as to extend along the seal line (FIG. 2). In the drawing, indicated by broken lines 14a and 17a).
[0024]
Further, the second elastic seal members 15 and 18 have a width slightly larger than the width of the metal beads 13 and 16 on the convex surface of the metal beads 13 and 16 and the flat surface portion of the substrate 2 continuous therewith. Two elastic sealing members 15 and 18 are formed. The height of the second elastic sealing members 15 and 18 is substantially the same as the height of the metal beads 13 and 16, and the surface (upper surface) is designed to be substantially flat. One or a plurality of upwardly projecting protrusions may be formed on the upper surfaces of the second elastic seal members 15 and 18 so as to extend along the seal line.
[0025]
Here, the width of the second elastic seal members 15 and 18 is preferably within 1.5 times the width of the metal beads 13 and 16. If it is too wide, the load will increase more than necessary. Further, the height of the second elastic seal members 15 and 18 is preferably 0.9 to 1.1 times the height of the metal beads 13 and 16. However, the range is not limited to the above range as long as the maximum amount of compressive deformation regulated by each thickened portion is smaller than the amount that causes compressive failure (for example, 40% or more) and a target spring force can be exhibited.
[0026]
In the metal gasket according to the present embodiment shown in FIG. 2, the plate constituting the shim 11 follows the surface (upper surface) of the substrate 2 in accordance with the shape of the inner bead BD1. It extends to a position beyond the position of the inner circumferential bead BD1. The portion 11b of the inner peripheral bead BD1 that contacts the metal bead 13 is bent and formed into a metal bead that engages with the metal bead 13, thereby reducing the thickness of the metal bead 13 of the inner peripheral bead BD1. The thickness of the inner bead BD1 is increased to increase the spring force. For this reason, the second elastic sealing material 15 is fixed to the convex side surface of the metal bead 13 via the portion 11b. However, the thickness of the metal bead 13 does not have to be increased by the portion 11b.
[0027]
In addition, the surface thickness extends over substantially the entire upper surface (the thickened side of the thickened portion) of the substrate 2 located between the inner circumferential seal line SL1 and the outer circumferential seal line SL2 or the third seal line SL3. The second thickened portion 20 is formed by fixing the adjustment plate 20a by welding, caulking, or the like. An arrangement position of the surface thickness adjusting plate 20a for forming the second thickened portion 20 in the present embodiment is a position indicated by oblique lines in FIG. 3, but is not limited thereto, and is not limited to this. The second thickened portion 20 may be formed by being fixed to the substrate.
[0028]
Here, when the thickness of the first thickened portion 7 including the shim 11 is defined as H1, the thickness of the second thickened portion 20 is defined as H2, and the thickness of the third thickened portion 10 is defined as H3. , H1> H2, and H1> H3, the thicknesses of the shims 11, 12 and the surface thickness adjusting plate 20a are adjusted. By making the first thickened portion 7 the thickest thickened portion, a surface pressure capable of sufficiently sealing the high-pressure gas in the combustion chamber can be generated in the first thickened portion 7. By adjusting the relationship between the plate thicknesses H1, H2, and H3 according to the rigidity of the engine and the like, the first thickened portion 7, the second thickened portion 20, and the third thickened portion are adjusted. The distribution of the limited surface pressure occurring at 10 is adjusted.
[0029]
Further, the height of the inner peripheral side bead BD1 at the time of no load is set higher than the height of the first thickened portion 7. The height of the outer peripheral side bead BD2 and the height of the third bead BD3 are set higher than the second thickened portion 20.
With this setting, when the metal gasket 1 having the above-described configuration is inserted between a cylinder block (not shown) and a cylinder head and tightened with bolts to apply a load, the first thickened portion having the largest thickness is formed. The maximum load is applied to 7 to seal the high-pressure gas in the combustion chamber.
[0030]
Further, the inner peripheral bead BD1 is compressed and deformed to a height regulated by the first and second thickened portions 7 and 20 to seal the outer periphery of the first thickened portion 7, and as a result, a burrow or the like in the sealing surface causes The gas leaked from the first thickening portion 7 is sealed. At this time, since the bead portion in contact with the seal surface of the engine is a soft rubber bead portion, it is possible to reliably seal even if there is a burrow, a tool mark, or the like on the seal surface.
[0031]
In addition, since the water holes 5 are also sealed by the third beads BD3 having the above configuration, the water flowing through the water holes 5 can be reliably sealed.
Further, the outer peripheral bead BD2 formed along the outer periphery of the substrate 2 prevents water or the like from entering the substrate 2 from the outside.
Here, the amount of compressive deformation of the third bead and the outer peripheral side bead BD2 is also regulated by the second thickened portion 20 and the third thickened portion 10.
[0032]
The amount of compressive deformation of each bead is set to a value that does not cause compressive breakage, for example, is set to be within a maximum of 40% based on the characteristics of the elastic sealing material used. The elastic sealing material may be made of a material having corrosion resistance and elasticity, such as a rubber material such as fluoro rubber, NBR, silicon rubber, or a resin material.
The bead BD according to the present embodiment described above has a structure in which a required sealing pressure is generated by a composite spring of the compression-deformed metal beads 13 and 16 and a rubber bead, so that the hardness of the substrate 2 forming the metal beads 13 and 16 is high. Can be reduced accordingly. In addition, the part of the bead that comes into contact with the upper and lower joint surfaces (seal surfaces) becomes a flat surface portion of the soft elastic seal material that has been compressed and deformed, and the soft elastic seal material is located at the contact surface portion of the engine that is in contact with the engine. By burying the processing tool mark, the combustion gas leaked from the first thickened portion 7 can be completely sealed even with pulsation pressurization due to operation of the engine.
[0033]
Here, in the case of a structure in which the elastic sealing material is filled only in the recesses of the metal beads 13 and 16, the metal beads 13 and 16 and the metal beads 13 and 16 are compressed and deformed. Then, an external force is generated which deforms the flat portions of the substrates 2 on both sides so as to warp upward. As the hardness of the substrate 2 is reduced for the purpose of suppressing the fatigue destruction of the metal beads 13 and 16 and the cost of the substrate, there is a possibility that the above-described deformation warping upward (convex side) may become apparent. In the embodiment, the second elastic seal members 15 and 18 are also arranged on the protruding portion side, and the deformation of the metal beads 13 and 16 and the substrate 2 is suppressed by the compression deformation of the second elastic seal members 15 and 18. This prevents the first elastic sealing members 14 and 17 in the recess from deteriorating the sealing performance. However, in the portions where the thickened portions are arranged near both sides of the metal beads 13 and 16, the thickened portions also have the function of suppressing the deformation, and accordingly, the second elastic sealing material is correspondingly used. The width of 15, 18 may be set small.
[0034]
Further, the first elastic sealing members 14 and 17 are covered with the metal beads 13 and 16 and are less likely to directly come into contact with gas, cooling water, lubricating oil and the like. Further, even in the second elastic sealing members 15 and 18, the portion directly in contact with the gas, the cooling water, the lubricating oil, and the like is mainly only on the side surface, and the second elastic sealing portions located on both sides of the metal beads 13 and 16. Are separated by the metal beads 13 and 16, so that even if one of the second elastic seal portions comes into contact with water or the like, the influence on the other second elastic seal can be suppressed.
[0035]
As described above, in the bead structure of the present embodiment, it is possible to reduce the hardness of the substrate 2 while ensuring a reliable sealing function, and a metal gasket structure that is hard to be fatigued even under repeated loads.
Also, by providing the second thickened portion 20 in addition to the first thickened portion 7 and the third thickened portion 10 as a thickened portion for regulating the amount of compressive deformation of each bead, pulsating pressurization due to engine operation can be reduced. Even if there is, it is possible to prevent the substrate 2 located between the inner peripheral seal line SL1 and the outer peripheral seal line SL2 from being deformed such that the substrate 2 is depressed, and the amount of compressive deformation of the bead itself is also changed. It is suppressed and leads to stabilization of sealing pressure by the bead.
[0036]
Further, in this embodiment, by providing the shim 11 with a spring, the spring element 11a of the shim 11 follows the first thickened portion 7 even if the surface pressure balance around the combustion chamber is lost during operation of the engine. The sealing pressure can be maintained in a predetermined range, and the leakage of gas from the first thickened portion 7 can be prevented accordingly. That is, even if there is a portion where the surface pressure is partially reduced due to thermal deformation during operation of the engine, the surface pressure is secured following the deformation.
[0037]
The height of the first thickened portion 7 in the circumferential direction may be varied so that the surface pressure of the first thickened portion 7 in the circumferential direction is equalized. Equalizing the surface pressure of the first thickened portion 7 along the circumferential direction contributes to the reduction of power loss and oil consumption while improving the roundness of the bore.
In the present embodiment, a sealing agent is applied to the lower surface of the substrate 2 and the upper surface of the thickened portion to complement the sealing performance on the metal surface.
[0038]
Here, as shown in FIG. 4, a sub-plate 22 having a size that can be substantially opposed to the entire surface of the substrate 2 may be disposed on the upper side of the substrate 2 so as to omit the application of the sealant. The auxiliary plate 22 has a role of protecting the elastic sealing members 15 and 18 on the convex side and adjusting the thickness of the entire gasket. An opening such as a water hole is also formed in the sub-plate 22.
[0039]
When the sub-plate 22 is provided, as shown in FIG. 5, instead of omitting the shim provided with the spring element, the portion of the sub-plate 22 facing the first thickened portion 7 is replaced with a metal bead. The spring element 22a may be formed by bending and forming in the thickness direction to form the spring element 22a. Note that the position where the spring element is provided on the sub-plate 22 is not limited to only the portion facing the first thickened portion 7. The above-mentioned spring element may be provided also in a portion facing a position on the substrate 2 where the surface pressure is likely to be unstable. In FIG. 5, the third thickened portion 10 is configured by fixing the surface thickness adjusting plate 24.
[0040]
At this time, as shown in FIG. 6, the normal thickness of the first thickened portion 7 along the circumferential direction is obtained by sandwiching the normal shim 23 having no spring element in the folded portion forming the first thickened portion 7. May be easily adjusted.
Here, in the above description, the surface thickness adjusting plate 20a forming the second thickened portion 20 is fixed to the substrate 2, but may be fixed to the sub-plate 22 side.
[0041]
In addition, from the viewpoint of providing a spring at the position of the first thickened portion 7, as shown in FIG. 7, the sub-plate 22 is stacked on the substrate 2 so as to face the concave portion of the metal bead 13. You may. However, it is preferable that a spring element 22a formed by bending the sub-plate is provided in a portion of the sub-plate 22 facing the first thickened portion 7.
The formation of the first thickened portion 7 is not limited to the formation by turning the end of the combustion chamber hole 3 side, but may be formed by fixing a surface pressure adjusting plate. In this case, the surface thickness adjusting plate itself may be bent to provide the first thickened portion 7 with a spring.
[0042]
Next, a second embodiment will be described with reference to the drawings. Note that the same members as those in the above embodiment are denoted by the same reference numerals and described.
As shown in FIG. 8, in the present embodiment, similarly to the first embodiment, the first thickened portion 7, the second thickened portion 20, the third thickened portion 10, the inner peripheral side bead BD1, the outer peripheral side A bead BD2 is provided, and a sub-plate 22 is provided so as to be opposed to the substrate 2. As shown in FIG. 4, the first thickened portion 7 and the third thickened portion provided on the substrate 2 in the first embodiment. The difference is that the part 10 is provided on the sub-plate 22 side.
[0043]
Further, in the present embodiment, the second substrate 2 is laminated on the substrate 2 via the sub-plate 22, and the inner peripheral seal line SL1 and the outer peripheral seal line SL2 are also applied to the second substrate 2. Are provided along the line (composition of the metal beads 13, 16 and the rubber beads).
That is, the metal gasket 1 of the present embodiment is configured such that the two substrates 2 on which the inner bead BD1, the outer bead BD2, and the third bead BD3 are formed along each seal line are connected to each other by bead protrusions. The side plates are arranged so as to face each other, and a sub-plate 22 having the first thickened portion 7 and the third thickened portion 10 is interposed between the two beads.
[0044]
Further, a surface thickness adjusting plate 20 a forming the second thickened portion 20 is fixed to the upper substrate 2. However, the first to third thickened portions 7, 10, and 20 may be formed on at least one of the two substrates 2 and the sub-plate 22, respectively.
Further, in the present embodiment, in order to suppress the amount of compressive deformation of the beads provided on the two substrates 2 within a predetermined range, the portion of the sub-plate 22 where the surface thickness adjusting plate 20a abuts slightly on the opposite side (lower side). Depressed.
[0045]
In the example shown in FIG. 8, a spring element 11 a is provided on the shim 11 in the first thickening portion 7 provided on the sub-plate, and a spring is applied to the first thickening portion 7. A spring may be applied to the first thickened portion 7 by forming a metal bead on the portion of the substrate 2 facing the first thickened portion 7.
As shown in FIG. 9, the shim 11 inserted in the first thickened portion 7 formed by folding is also extended to the outer peripheral side, and a position where the surface pressure is likely to be unstable is bent and formed in the thickness direction. A spring element may be formed to supplement the surface pressure. FIG. 9 shows an example in which a surface thickness adjusting plate 20 a constituting the second thickened portion 20 is arranged on the sub plate 22.
[0046]
Another embodiment is shown in FIGS. Although this embodiment is an example in which a spring element is not provided to the first thickened portion, a spring element may be provided to the position of the first thickened portion. Also, as shown in FIG. 10, two or more sub-plates may be stacked and arranged. Further, the auxiliary plate may be omitted.
Further, in all of the above embodiments, the case where a full bead is employed as a convex metal bead on one surface side is illustrated, but as shown in FIG. 15, a half bead is employed as a convex metal bead on one surface side. May be adopted. In FIG. 15, all or a part of the metal bead 16 constituting the outer peripheral side bead BD2 is formed as a half bead, and the elastic sealing material 18 is fixed to the convex portion side, and the elastic sealing material 17 is also filled in the concave portion on the back side of the convex portion. ing. When a half bead is used, the bead width can be reduced.
[0047]
Further, in all of the above embodiments, the case where the third thickened portion 10 is provided is illustrated, but the third thickened portion may be omitted. Even if the third thickened portion 10 is omitted, the amount of compressive deformation of the outer peripheral bead BD2 can be regulated by the second thickened portion 20.
Further, the second thickened portion 20 is configured by providing the surface thickness adjusting plate 20a, but the second thickened portion is formed by relatively thickening the position of the second thickened portion itself on the sub-plate. You may do it.
The functions and effects are the same as in the first embodiment.
[0048]
【The invention's effect】
As described above, when the present invention is adopted, a metal gasket 1 capable of securing the function of sealing high-pressure gas in a combustion chamber and ensuring complete sealing performance over a long period of time at a low surface pressure on a sealing surface with poor surface roughness can be obtained. Can be provided.
[Brief description of the drawings]
FIG. 1 is a plan view showing a metal gasket according to a first embodiment of the present invention.
FIG. 2 is a sectional view taken along line BB in FIG.
FIG. 3 is a diagram showing an arrangement position of a surface thickness adjusting plate.
FIG. 4 is a sectional view showing another configuration of the metal gasket.
FIG. 5 is a sectional view showing another configuration of the metal gasket.
FIG. 6 is a cross-sectional view showing another configuration of the metal gasket.
FIG. 7 is a sectional view showing another configuration of the metal gasket.
FIG. 8 is a sectional view showing a metal gasket according to a second embodiment of the present invention.
FIG. 9 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 10 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 11 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 12 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 13 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 14 is a sectional view showing another metal gasket according to the second embodiment of the present invention.
FIG. 15 is a diagram showing an example of a case where a metal bead of an outer peripheral side bead is constituted by a half bead.
FIG. 16 is a cross-sectional view for explaining a conventional example.
FIG. 17 is a cross-sectional view for explaining a conventional example.
[Explanation of symbols]
1 Metal gasket
2 substrate
3 combustion chamber holes
4 bolt holes
5 water holes
6 Oil hole
7 First thickening part
10 Third thickening part
11 Shim
11a Spring element
13,16 Metal beads
14, 17 First elastic sealing material (rubber bead)
15, 18 Second elastic sealing material (rubber bead)
20 Second thickening part
20a Surface thickness adjustment plate
22 Subboard
22a Spring element
BD1 Inner circumference bead
BD2 Outer side bead

Claims (10)

At least with respect to a substrate made of a thin metal plate having an open combustion chamber hole, it extends along the open end of the combustion chamber hole so as to surround the combustion chamber hole in an endless annular shape and is formed thicker than other portions. A first thickened portion made of metal, an inner circumferential bead surrounding the first thickened portion and the combustion chamber hole endlessly around the outer periphery of the first thickened portion, and an outer circumferential portion of the substrate. An outer peripheral bead that extends, and a metallic second thickened portion disposed between the inner peripheral bead and the outer peripheral bead and formed to be thicker than other portions,
When the thickness of the first thickened portion is H1 and the thickness of the second thickened portion is H2, the relationship of H1> H2 is set;
The inner peripheral bead is formed by bending the substrate in the thickness direction to be convex on one surface side, the height of the convex portion being higher than the first thickened portion, and the convex portion side surface of the metal bead. And a rubber bead made of an elastic sealing material that is filled in the concave portion on the back side of the convex portion and is compressed and deformed in the plate thickness direction together with the deformation of the metal bead,
The outer peripheral side bead is formed by bending the substrate in the plate thickness direction to be convex on one surface side, and the convex portion height is higher than the second thickened portion, and the convex portion side surface of the metal bead. A metal gasket comprising a combination of a rubber bead made of an elastic sealing material which is fixed and filled in a concave portion on the back side of the convex portion and is deformed in the thickness direction along with the deformation of the metal bead. In the case where the substrate is provided with a metallic third thickened portion formed to be thicker on the outer circumferential side than the outer circumferential bead than other portions, and the plate thickness of the third thickened portion is H3. 2. The metal gasket according to claim 1, wherein a relationship of H1> H3 is set. The metal gasket according to claim 1 or 2, wherein the first thickened portion is formed by folding an end of the combustion chamber hole side, and a shim is inserted in the folded portion. A sub-plate laminated and arranged so as to face the substrate from the convex portion side of the bead. The sub-plate is bent in the thickness direction at a position of the sub-plate facing the first thickened portion. The metal gasket according to any one of claims 1 to 3, wherein a spring element capable of exerting a spring force in a thickness direction by molding is provided. The metal gasket according to claim 3, wherein the shim includes a spring element that is bent and formed in a thickness direction and can exert a spring force in the thickness direction. The metal gasket according to claim 5, further comprising a sub-plate stacked and arranged so as to face the substrate from the convex portion side of the bead. A sub-plate is provided on the substrate, and the sub-plate is bent and formed in a thickness direction with respect to a portion of the substrate including a portion facing the first thickened portion in the thickness direction, where a surface pressure change is likely to occur. The metal gasket according to any one of claims 1 to 6, wherein a spring element is provided. Comprising two substrates arranged in a stack and a sub-plate interposed between the two substrates, wherein the two substrates and the sub-plate are each made of a thin metal plate having at least a combustion chamber hole opened;
At least one of the two substrates and the sub-plate extends along the opening end of the combustion chamber hole so as to surround the combustion chamber hole in an endless annular shape, and is thicker than other portions. Forming a first thickened portion of metal,
Each of the two substrates is provided with an inner peripheral bead surrounding the combustion chamber hole endlessly at an outer peripheral position than the first thickened portion and an outer peripheral bead extending along the outer peripheral end of the substrate. ,
A metallic second thickened portion formed between the inner circumferential bead and the outer circumferential bead and formed thicker than other portions with respect to at least one of the two substrates and the sub plate. And
When the thickness of the first thickened portion is H1 and the thickness of the second thickened portion is H2, the relationship of H1> H2 is set;
The inner peripheral bead is formed by bending the substrate in the plate thickness direction to form a convex shape on the sub-plate side, the height of the convex portion being higher than the first thickened portion, and the convex portion side surface of the metal bead. And a rubber bead made of an elastic sealing material that is fixed and filled in the concave part on the back side of the convex part and is compressed and deformed in the thickness direction together with the deformation of the metal bead. The metal bead is bent in the direction and becomes convex on the sub-plate side, and the height of the convex portion is higher than the second thickened portion. The metal bead is fixed to the convex side surface of the metal bead and is filled in the concave portion on the back side of the convex portion. A metal gasket comprising a combination of a rubber bead made of an elastic sealing material that is compressed and deformed in the thickness direction together with the deformation of the metal bead. Forming at least one of the two substrates and the sub-plates on the outer peripheral side of the outer peripheral side bead and a third thickened portion made of a metal and having a thickness larger than that of the other part; 9. The metal gasket according to claim 8, wherein, when the thickness of the thick portion is H3, the relationship of H1> H3 is set. At the first thickening portion position, at least one of the sub-plate and the two substrates is provided with a metallic spring element bent and formed in the plate thickness direction and capable of exerting a spring force in the plate thickness direction. The metal gasket according to claim 8, wherein the metal gasket is a metal gasket.

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