JPH0744849Y2 - Metal cylinder head gasket with seal ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is directed to a metal cylinder with a seal ring, which is sandwiched between a lower surface of a cylinder head and an upper surface of a cylinder block of an internal combustion engine to maintain airtightness and liquidtightness between both surfaces. Regarding improvement of head gasket.

(Prior Art) A cylinder head gasket is sandwiched between the lower surface of a cylinder head and the upper surface of a cylinder block of an internal combustion engine to allow high-pressure combustion gas generated in the cylinder or flow between the cylinder block and the cylinder head. This prevents the cooling water and lubricating oil from leaking to the outside.

FIG. 4 shows an example of such a cylinder head gasket 1. In this cylinder head gasket 1,
Circular bore hole 2 matching the opening shape of the cylinder top,
2, small circular holes 3 and 3 for inserting bolts for fixing the cylinder head to the cylinder block, and through holes 4 and 4 for passing cooling water and lubricating oil. 5 is each bore hole 2, 2
It is a grommet made of a thin metal plate attached to the inner peripheral edge of the.

Conventionally, such a cylinder head gasket 1 is configured by stacking a plurality of metal thin plates such as a galvanized steel plate and a stainless steel plate in which the bore hole 2 and the like are punched and formed.

FIG. 5 shows an example of a conventional metal cylinder head gasket formed of a thin metal plate as described above. In the metal cylinder head gasket illustrated in FIG. 5, layers of sealing materials 6, 6 such as nitrile butadiene rubber (NBR), silicon rubber, and fluororubber are formed on both front and back surfaces by baking or the like, and further bore holes are formed. 2. Two thin metal plates 9, 9 each having a small circular hole through which a bolt for fixing the cylinder head 7 to the cylinder block 8 is inserted, and a through hole 4 for passing cooling water or lubricating oil. Thin metal plate 9,
As in the case of 9, the hole 2, the small circular hole, and the other thin metal plate 10 having the through hole 4 are formed so that the holes 2 and 4 formed in these three thin metal plates 9 and 10 are aligned with each other. Are laminated in a sandwich shape, and a grommet 5 made of a thin metal plate is further provided on the peripheral portion of the bore hole 2 so that the peripheral portion of each bore hole 2 can be reliably kept airtight.

A ridge 11 is formed around the through hole 4 to improve the contact pressure in the peripheral portion of the through hole 4 and prevent leakage of cooling water and lubricating oil flowing inside the through hole 4. ing.

By the way, in the metal cylinder head gasket thus formed, in order to more reliably prevent the cooling water and the lubricating oil flowing through the through holes 4 from leaking to the outside, a seal ring is provided inside each of the through holes 4. It is done to install the parts called.

The seal ring thus mounted inside each through hole 4 is configured as shown in FIG. 6, for example. The seal ring 12 shown in FIG. 6 is constructed by baking a seal material 14 such as silicon rubber or fluororubber on both upper and lower surfaces of a cored bar 13 formed according to the shape of the through hole 4 to be mounted. .

When the seal ring 12 as described above is mounted inside the through hole 4, it is conventionally performed as shown in FIG.

That is, in order to form the through hole 4, among the holes formed in the plurality of metal thin plates constituting the metal cylinder head gasket, the holes 17 formed in the metal thin plates 15 and 15 located in the intermediate portion,
The inner diameter of 17 is made larger than the inner diameters of the holes 18, 18 formed in the thin metal plates 16, 16 located on the front and back ends, respectively,
While inserting the core metal 13 that constitutes the inside of the holes 17, 17 formed in the metal thin plates 15, 15 of the intermediate portion, the outer peripheral edge portion of the core metal 13 of the metal thin plates 16, 16 on both front and back sides. It is sandwiched by the inner peripheral edge.

(Problems to be solved by the invention) However, in the conventional metal cylinder head gasket in which the seal rings 12 are mounted inside the through holes 4 and 4 as described above, the following inconvenience occurs. It was

That is, since the plurality of metal thin plates 15 and 16 forming the metal cylinder head gasket form the bore holes 2 and 2 and the through holes 4 and 4, the holes 17 and 18 formed in the metal thin plates 15 and 16 are connected to each other. In order not to shift, it is only joined at several points by eyelets or the like, and it is unavoidable that the distance between the superposed metal thin plates 15 and 16 widens in the portion apart from the eyelets. Therefore, as described above, the seal ring 12 that easily sandwiches the outer peripheral edge of the cored bar 13 between the inner peripheral edges of the metal thin plates 16 on both front and back sides is likely to fall off. When the metal cylinder head gasket is in use, the seal ring 12 is also sandwiched between the cylinder block upper surface and the cylinder head lower surface, so it will not fall off. The seal ring 12 easily falls off from the inside of the through hole 4 when it is transported.

The dropped seal ring is easily lost, and the metal cylinder head gasket with lost seal ring deteriorates the sealing performance around the through hole, which may cause an engine failure when used as it is.

In order to eliminate such an inconvenience, it is possible to form a rubber layer directly on the metal thin plate 15 which constitutes the intermediate layer of the metal cylinder head gasket, and to fulfill the role of the seal ring, but it takes time and effort for manufacturing. This is not preferable.

That is, the metal thin plate 15 is the core metal 13 that constitutes the seal ring 12.
Since it is considerably larger than the above, the mold for forming the rubber layers on both sides of the metal thin plate 15 becomes large, and it becomes difficult to burn the rubber layers to a large number of metal thin plates at a time, and the manufacturing cost of the metal cylinder head gasket is increased. It gets bulky.

Further, when casting a cylinder head or cylinder block having a passage for lubricating oil or cooling water inside, it is necessary to provide more openings than necessary on the top surface of the cylinder block and the bottom surface of the cylinder head. The opening must be closed by a cylinder head gasket. In such a case, it is necessary to bake rubber in a part of the metal thin plate 15 which has no hole, but such baking work to a non-hole part is more difficult than baking work to a part having a hole. .

In order to solve the above-mentioned inconvenience, the present invention aims to provide a metal cylinder head gasket with a seal ring, which can be manufactured at a relatively low cost and in which the seal ring mounted inside the through hole does not fall off. There is.

(Means for Solving the Problems) The metal cylinder head gasket with a seal ring of the present invention has at least the first, second, and third metal sheets, like the above-described conventional metal cylinder head gasket with a seal ring. A thin plate is laminated by sandwiching the first thin metal plate between the second and third thin metal plates, and a bore hole that matches the opening of the cylinder and a through hole that matches the opening of the water oil hole. , And a seal ring supported inside the through hole.

Further, in the metal cylinder head gasket with a seal ring according to the present invention, the seal ring comprises a core metal, an elastic seal material reinforced by the core metal, and an outer peripheral edge of the seal material. It has a formed tongue piece and a locking projection integrally formed on one surface of the tongue piece. And
A locking hole for elastically engaging the locking projection is formed at a position of the first thin metal plate in the vicinity of the through hole and in alignment with a part of the tongue piece. Form a relief hole or notch in a part of the second thin metal plate that is aligned with this locking hole, and a part of the third thin metal plate that is aligned with the tongue. The thinned portion has a structure in which the third thin metal plate does not overlap the first and second thin metal plates in the portion.

(Operation) The operation itself of the metal cylinder head gasket with a seal ring of the present invention configured as described above is the same as that of the conventional metal cylinder head gasket with a seal ring, but the metal cylinder head gasket with a seal ring of the present invention In this case, since the seal ring is firmly supported by the first thin metal plate by the engagement between the engagement projection and the engagement hole, the seal ring is not supported between the cylinder block upper surface and the cylinder head lower surface. The seal ring will not fall off before mounting.

Further, when the metal cylinder head gasket with a seal ring of the present invention is strongly sandwiched between the upper surface of the cylinder block and the lower surface of the cylinder head, the above-mentioned locking protrusion is crushed, but with a part of the second thin metal plate, Since a relief hole or a notch is formed in a portion of the locking projection that is aligned with the engaged locking hole, the pressing force of the locking projection mounting portion does not become excessively large.

Similarly, since a part of the third thin metal plate that is aligned with the tongue piece is a thinned portion, the pressing force of the part where the tongue piece is present does not become excessively large. The thinned portion includes not only a notch continuous from the peripheral edge of the through hole to the outside in the diametrical direction of the through hole, but also a portion excluding a wide range that cannot be called a notch. In short, the thinned portion has a sufficient area to reliably prevent the third thin metal plate and the tongue piece from overlapping with each other.

(Embodiment) Next, the present invention will be described in more detail with reference to the illustrated embodiment.

1 and 2 show an embodiment of the present invention, FIG. 1 is an enlarged sectional view of a seal ring supporting portion, and FIG. 2 is an exploded perspective view of the same.

The illustrated metal cylinder head gasket with a seal ring is made up of four metal thin plates 19, 20,
21 and 22 are overlapped with each other to form a bore hole 2 (see FIG. 4) matching the opening of the top of the cylinder and a through hole 4 matching the opening of the water / oil hole. It is used in a state of being sandwiched between the lower surface of the head 7 (see FIG. 5).

A seal ring 12 is supported inside the through hole 4 for the purpose of improving the sealing performance around the through hole 4, but the seal ring 12 used in the metal cylinder head gasket with a seal ring of the present invention is , A core metal 13, an elastic sealing material 14 reinforced by the core metal 13, and the sealing material
The tongue piece 23 is integrally formed on the outer peripheral edge of the tongue 14, and the locking projection 24 is integrally formed on one surface of the tongue piece 23. The locking projection 24 is formed in a substantially inverted truncated cone shape so that the base portion near the tongue piece 23 has a small outer diameter and the outer diameter gradually increases as the distance from the tongue piece 23 increases.

Then, among the first to fourth metal thin plates 19 to 22, a locking hole 25 is formed in a part of the first metal thin plate 19 located in an intermediate portion in the vicinity of the through hole 4. ing. This locking hole 25
Is for elastically engaging the locking projection 24, and the inner diameter R of the locking hole 25 is at least smaller than the outer diameter D of the tip of the locking projection 24 (R <D). is doing.

Further, a relief hole 26 having a slightly larger inner diameter than the locking hole 25 is formed in a portion of the second metal thin plate 20 which is also located in the middle part and is aligned with the locking hole 25. There is.

Furthermore, the third and fourth thin metal plates 21, which are located on both front and back ends,
A portion of 22 which is aligned with the tongue piece 23 is a thinned portion, and the third and fourth thin metal plates 21, 22 are formed in the portion.
However, the structure is such that it does not overlap the first and second metal thin plates 19 and 20.

That is, in the illustrated embodiment, since the through hole 4 is formed, the inner diameters of the holes 27 and 27 formed in the third and fourth thin metal plates 21 and 22 are also used to form the through hole 4. The inner diameter of the holes 28, 28 formed in the first and second thin metal plates 19, 20 is made sufficiently large so that the tongue piece 23 exists inside the holes 27, 27.

As shown in FIG. 1, each member configured as described above forms the through hole 4 in the main body portion of the seal ring 12 (the portion excluding the tongue piece 23 and the locking projection 24). First and second sheet metal
Located inside the holes 28, 28 formed in 19, 20, the tongue 23
By sandwiching the first and second thin metal plates 19 and 20 with each other, and engaging the locking projection 24 formed on the tongue piece 23 with the locking hole 25 formed on the first thin metal plate 19. , The first thin metal plate 19 is supported.

The action itself of the metal cylinder head gasket with a seal ring of the present invention configured as described above is the same as that of the conventional metal cylinder head gasket with a seal ring,
The liquid tightness around the water / oil holes formed on the engine side is maintained by the seal material 14 of the seal ring 12.

Furthermore, in the metal cylinder head gasket with a seal ring according to the present invention, the seal ring 12 has a locking protrusion.
Since the 24 and the locking holes 25 are firmly supported to the first thin metal plate 19, the first to the fourth metal blocks are mounted before being mounted between the upper surface of the cylinder block and the lower surface of the cylinder head. Even in a state where the distance between the metal thin plates 19 to 22 widens,
The seal ring 12 will not fall off.

Also, when the metal cylinder head gasket with a seal ring of the present invention is strongly sandwiched between the upper surface of the cylinder block and the lower surface of the cylinder head, the locking projection 24 is crushed and a part of the tongue piece 23 The part where the locking protrusion 24 is formed is
Although it bulges toward the second metal thin plate 20, at a portion of this second metal thin plate 20, which is aligned with the locking hole 25 with which the locking projection 24 is engaged, this locking is performed. Since the escape hole 26 which is slightly larger than the hole 25 is formed, even if the metal cylinder head gasket with a seal ring is strongly sandwiched between the cylinder block upper surface and the cylinder head lower surface, The pressing force does not become useless.

Similarly, since the through holes 4 are formed, the third and fourth metal thin plates 2
The inner diameter of the holes 27, 27 formed in 1, 22 should be large enough,
Since the tongue piece 23 is made to exist inside the holes 27, 27, the pressing force of the portion where the tongue piece 23 is present does not become excessively large.

As a result, the seal material 14 of the seal ring 12 is uniformly pressed against the upper surface of the cylinder block and the lower surface of the cylinder head over the entire circumference thereof, and the liquid-tightness around the through hole 4 is sufficiently maintained.

The locking projection 24 formed on a part of the tongue piece 23 may be a solid body as shown in FIGS. 1 and 2, but if it is a hollow cylinder as shown in FIG. The elastic deformation can be performed with a light force, so that the mounting work in the locking hole 25 can be facilitated.

(Effect of the device) Since the metal cylinder head gasket with a seal ring of the present invention is configured and operates as described above, the seal ring for maintaining the sealing property around the through hole is prevented from falling off during transportation, The production of defective metal cylinder head gaskets due to loss of the seal ring can be prevented, and the product yield can be improved.

Further, without using the metal cylinder head gasket with the seal ring falling off, there is no danger of causing leakage of cooling water or lubricating oil and causing engine failure.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is an enlarged sectional view of a seal ring supporting portion, FIG. 2 is an exploded perspective view of the same, and FIG. Fig. 4 is a partial sectional view showing an example, Fig. 4 is a plan view showing an example of a conventional cylinder head gasket, and Fig. 5 is a first example of a conventional metal cylinder head gasket sandwiched between a cylinder head and a cylinder block. 4 is a perspective view showing an example of a conventional seal ring, and FIG. 7 is a view showing a second example of a conventional metal cylinder head gasket. It is a perspective view. 1: Cylinder head gasket, 2: Bore hole, 3: Small circular hole, 4:
Through hole, 5: Grommet, 6: Seal material, 7: Cylinder head,
8: Cylinder block, 9, 10: Thin metal plate, 11: Ridge, 12:
Seal ring, 13: core metal, 14: seal material, 15, 16: metal thin plate, 17, 18: hole, 19: first metal thin plate, 20: second metal thin plate, 21: third metal thin plate, 22: fourth thin metal plate, 23: tongue piece, 24: locking projection, 25: locking hole, 26: escape hole, 27, 28: hole.

Claims (1)

[Scope of utility model registration request] 1. A cylinder comprising at least three first, second and third thin metal plates stacked with the first thin metal plate sandwiched between the second and third thin metal plates. In a cylinder head gasket with a seal ring having a bore hole matching the opening, a through hole matching the opening of the water / oil hole, and a seal ring supported inside the through hole, the seal ring is a core. Gold, a sealing material made of an elastic material reinforced by the core metal, a tongue piece integrally formed on the outer peripheral edge of the sealing material, and a locking projection integrally formed on one surface of the tongue piece. A part of the first thin metal plate, located in the vicinity of the through hole, and at a position aligned with a part of the tongue,
A locking hole for elastically engaging the locking projection is formed, and a relief hole or a notch is formed in a part of the second thin metal plate that is aligned with the locking hole. A part of the metal thin plate that is aligned with the tongue piece is a thinned part, and the third metal thin plate does not overlap with the first and second metal thin plates in the part. A metal cylinder head gasket with a seal ring, which is characterized.