JPH0330746B2 - - Google Patents

Description

[Detailed Description of the Invention] a. Purpose of the Invention (Field of Industrial Application) The cylinder head gasket according to the present invention includes:
It is used by being sandwiched between the top surface of the engine's cylinder block and the bottom surface of the cylinder head in order to maintain airtightness and liquidtightness between the two surfaces.

(Prior art) A cylinder head gasket is sandwiched between the lower surface of the cylinder head and the upper surface of the cylinder block of an internal combustion engine to prevent high-pressure combustion gas generated within the cylinder from leaking to the outside or from colliding with the cylinder block. This prevents leakage of cooling water and lubricating oil flowing between the cylinder head and the cylinder head.

FIG. 5 shows an example of a cylinder head gasket used in such a case. This cylinder head gasket 1 has circular bore holes 2, 2 that match the opening shape of the top of the cylinder, small circular holes 3, 3 through which bolts for fixing the cylinder head to the cylinder block are inserted, and cooling water and lubricating holes. Through-holes 4, 4 (the shape is not necessarily circular) are provided to allow oil to pass through. Reference numeral 5 designates a grommet made of a thin metal plate attached to the inner peripheral edge of each bore hole 2,2.

By the way, in the cylinder head gasket formed in this way, in order to effectively prevent the cooling water and lubricating oil flowing inside the through holes 4, 4 from leaking to the outside, each through hole 4, 4 is A part called a seal ring is installed inside the seal ring.

The seal rings mounted inside each of the through holes 4, 4 in this manner are constructed as shown in FIG. 6, for example. The seal ring 6 shown in Fig. 6 is made to be installed inside the circularly formed through hole 4, and the size of the outer circumference is adjusted to match the inner peripheral shape of the through hole 4 to be installed. As shown in FIG. 7, a sealing material 8 such as NBR is baked onto both the upper and lower surfaces of the formed ring-shaped metal substrate 7. The sealing material 8 is baked onto the substrate 7 so as to cover the outer periphery of the substrate 7, as shown in FIG. 8, or is applied to cover the inner periphery of the substrate 7, as shown in FIGS. In some cases, it may be printed onto the substrate 7 in a similar manner.

Regarding the seal ring 6 shown in FIGS. 7 and 8, in any case, when the seal ring 6 is installed inside the through hole 4, this seal ring 6
is fitted inside the through hole 4, and forms the outer periphery of the seal ring 6 (in the case of FIGS. 6 and 7), or the outer periphery of the sealing material 8 (in the case of FIG. 8).
and the inner peripheral edge of the through hole 4 are bonded together with an adhesive such as room temperature vulcanizable silicone.

In addition, in the structure shown in FIGS. 9 and 10, a part of the sealing material 8 that covers the inner peripheral edge of the substrate 7 and is baked on the substrate 7 is extended to the outside of the substrate 7 and connected. A short cylindrical fitting piece 10 made of a sealing material is formed at the tip of the connecting part 9.

On the other hand, on the inner peripheral edge of the through hole 4 into which the substrate 7 of the seal ring 6 is to be fitted, there is a communicating part 11a into which the connecting part 9 can be freely inserted, and the fitting piece 10 is arranged so that its outer diameter D is elastically adjusted. Inner diameter d that can be inserted freely in compressed state (<D)
A notch 11 consisting of a fitting part 11b having a
It is formed.

When the seal ring 6 is mounted inside the through hole 4 with the above-described structure, the substrate 7 is placed inside the through hole 4, the connecting portion 9 is placed on the communicating portion 11a of the notch 11,
At the same time, insert the fitting piece 10 into the notch 1.
1 into the fitting part 11b at the tip. Fitting part 11
The outer circumferential surface of the fitting piece 10 pushed inside b is elastically pressed against the inner circumferential surface of the fitting part 11b and is held within this fitting part 11b, so that the fitting piece 10 and the connecting part 9 A substrate 7 connected through the through hole 4 is held within the through hole 4.

(Problems to be Solved by the Invention) However, in the conventional cylinder head gasket in which the seal ring 6 is mounted inside each of the through holes 4, 4 as described above, there are the following disadvantages. occured.

That is, the thickness of the metal substrate 7 constituting the seal ring 6 is as small as about 0.5 mm. Therefore, when the seal ring 6 is fixed inside the through hole 4 by adhesive, the adhesive area is small; It is inevitable that the adhesive strength will weaken. This means that even if the substrate 7 is exposed at the outer periphery of the seal ring 6 as shown in FIG. The same applies even if it is a covering structure.

If the adhesive strength when adhering the seal ring 6 to the inside of each of the through holes 4 is weakened, the seal ring 6 will easily fall off from the inside of the through hole 4.
When the cylinder head gasket 1 is in use, the seal ring 6 is also held between the top surface of the cylinder block and the bottom surface of the cylinder head, so it will not fall off. When transporting the seal ring 6, the seal ring 6 tends to fall off from inside the through hole 4.

The fallen seal ring 6 is easy to lose, and the cylinder head gasket 1 that has lost the seal ring 6
Otherwise, the sealing performance around the through hole 4 will deteriorate, which may cause engine failure if used as is.

Furthermore, in the case of the structure shown in FIGS. 7 and 8, a step of applying an adhesive between the seal ring 6 and the through hole 4 is required, which increases the number of manufacturing steps and increases the product cost.

Moreover, as shown in FIGS. 9 and 10, the seal ring 6
Even in a structure in which a part of the sealing material 6 extending outward is fitted into a notch formed at the peripheral edge of the through hole 4, the seal ring 4 cannot be held inside the through hole 4. It is easy for the seal ring 6 to become completely damaged, and it is easy for the seal ring 6 to fall off or be lost.

In order to eliminate the above-mentioned disadvantages, the present invention provides a cylinder head gasket in which a seal ring can be attached without using an adhesive, and the seal ring adhered to the inside of the through hole will not fall off. is intended to do.

b. Structure of the Invention (Means for Solving the Problem) The cylinder head gasket of the present invention, like the conventional cylinder head gasket described above, has a circular bore hole that matches the shape of the opening at the top of the cylinder and allows fluid to pass therethrough. A through hole is provided for this purpose. A grommet made of a thin metal plate is attached to the inner peripheral edge of the bore hole, and a seal ring made of a metal annular substrate with sealing material provided on both sides is attached to the inside of the through hole.

Furthermore, in the cylinder head gasket of the present invention, the T-shaped extending portions formed outward at multiple locations on the outer peripheral edge of the substrate of the sealing material are arranged at 90 degrees with respect to the substrate. It is also made into a locking part by twisting it at a slightly smaller angle.

This locking portion is inserted into a notch formed at a position aligned with the locking portion at the outer peripheral edge of the through hole, and both sides of the locking portion protrude from both upper and lower surfaces of the sheet constituting the cylinder head gasket. The substrate is supported inside the through hole by being bent toward both the upper and lower surfaces of the sheet.

(Function) When the cylinder head gasket of the present invention constructed as described above is used by being sandwiched between the upper surface of the cylinder block and the lower surface of the cylinder head, the function of the cylinder head gasket itself is as described above. This is exactly the same as in the conventional cylinder head gasket.

However, in the cylinder head gasket of the present invention, the substrate constituting the seal ring mounted inside the through hole is bent at both ends of the locking portions provided at multiple locations on the outer periphery of the substrate. Since it is firmly supported inside the hole, the seal ring will not fall out from inside the hole even before the cylinder head gasket is sandwiched between the top surface of the cylinder block and the bottom surface of the cylinder head. .

(Example) Next, the present invention will be explained in more detail by explaining the illustrated embodiment.

1 to 3 show an embodiment of the present invention. FIG. 1 is an exploded perspective view showing the main parts of a cylinder head gasket, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. After inserting the locking part into the inside of the notch, and before bending the locking part, the cross-sectional view taken along line B-B in FIG. It is a figure similar to the figure.

In order to circulate cooling water or lubricating oil between the cylinder block and the cylinder head, three outer peripheral edges of the through hole 4 formed in the cylinder head gasket 1 are provided with a width W in the radial direction. The notches 12, 12 are formed at equal intervals from each other.

On the other hand, a sealing material 6 installed inside the through hole 4
At three locations on the outer peripheral edge of the annular substrate 7 constituting the holder, T-shaped extending portions are formed toward the outside at equal intervals. This extension part is formed at an angle smaller than 90 degrees with respect to the substrate, for example, about 80 degrees.
By twisting in the same direction, the width W of the notches 12, 12
The locking portions 13, 13 have a width w (W>w, see FIG. 2) that is slightly smaller than the width w (W>w, see FIG. 2).

A seal ring 6 having a substrate 7 having locking portions 13, 13 as described above formed on its outer peripheral edge, and a through hole 4 having cutouts 12, 12 as described above formed on its inner peripheral edge.
If you want to attach it to the inside of the body, do it as follows.

That is, the locking portions 13, 1 at three locations on the outer peripheral edge of the substrate 7
3 is inserted into the notches 12, 12 formed at three positions on the outer peripheral edge of the through hole 4 until the substrate is located exactly at the inner middle part of the through hole 4.

In this state, the above three locking parts 1
Since the upper and lower ends of the cylinder head gaskets 3 and 13 protrude from both the upper and lower surfaces of the sheet 14 constituting the cylinder head gasket, the sheet 14 is then crushed between the upper and lower dies of a press, etc. Both upper and lower ends of each of the locking portions 13, 13 are bent toward both the upper and lower surfaces of the sheet 14.

By this bending operation, each locking portion 13, 13
Both upper and lower ends of the notches 12 hold down the edges of the notches 12, 12, and firmly support the substrate 7 inside the through hole 4.

The cylinder head gasket of the present invention is constructed by assembling each part having the above-mentioned configuration, but when this cylinder head gasket is used by being sandwiched between the upper surface of the cylinder block and the lower surface of the cylinder head, The function of the cylinder head gasket itself is exactly the same as that of the conventional cylinder head gasket described above, but in the case of the cylinder head gasket of the present invention, as described above, it is installed inside the through hole 4. A substrate 7 forming a seal ring 6 is firmly supported inside the through hole 4 by bending both ends of locking portions 12, 12 provided at three positions on the outer peripheral edge of the substrate 7.

Therefore, the seal ring 6 will not accidentally fall off from inside the through hole 4, and it is possible to prevent deterioration of sealing performance and product yield due to the seal ring 6 falling off or being lost.

c. Effects of the Invention Since the cylinder head gasket of the present invention is constructed and operates as described above, it not only reduces the number of man-hours and manufacturing costs by omitting the adhesive application process, but also reduces the amount of gas around the through-hole. This prevents the seal ring that maintains the sealing performance from falling off during transportation, prevents the occurrence of defective cylinder head gaskets due to loss of the seal ring, and improves product yield.

Furthermore, there is no risk of engine failure due to leakage of cooling water or lubricating oil due to unknowing use of a cylinder head gasket with a fallen seal ring.

[Brief explanation of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is an exploded perspective view showing the main parts of a cylinder head gasket, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG. After inserting the locking part into the inside of the notch, and before bending the locking part, the cross-sectional view taken along line B-B in FIG. Figure 5 is a plan view showing an example of a cylinder head gasket, and Figure 6 is a diagram showing one example of a seal ring attached to a conventional cylinder head gasket.
A perspective view showing an example, FIG. 7 is a sectional view showing a state in which this seal ring is installed inside a through hole, and FIG. 8 is a sectional view showing a state in which seal rings of different shapes are installed inside a through hole. Figures 9 and 10 show another example of the seal ring mounting part, Figure 9 is an exploded perspective view, and Figure 10 is an assembled state.
-C sectional view. 1: Cylinder head gasket, 2: Bore hole,
3: Small circular hole, 4: Through hole, 5: Grommet, 6: Seal ring, 7: Substrate, 8: Seal material, 9: Connecting part, 10: Fitting piece, 11: Notch, 11a: Communication part, 11b: Fitting portion, 12: Notch, 13: Locking portion, 14: Sheet.

Claims (1)

[Claims] 1. A circular bore hole that matches the opening shape of the top of the cylinder and a through hole for passing fluid are bored, a grommet made of a thin metal plate is placed on the inner peripheral edge of the bore hole, and a grommet made of metal is placed inside the through hole. In a cylinder head gasket each equipped with a seal ring having a sealing material on both sides of an annular substrate, Ts are formed outward at multiple locations on the outer peripheral edge of the substrate of the sealing material.
The extending portion of the letter shape is twisted at an angle slightly smaller than 90 degrees with respect to the substrate to form a locking portion, and this locking portion is formed at a position aligned with the locking portion at the outer peripheral edge of the through hole. The substrate is inserted into the notch, and both ends of the locking portion protruding from both the upper and lower surfaces of the sheet constituting the cylinder head gasket are bent toward the upper and lower surfaces of the sheet, and the substrate is supported inside the through hole. and cylinder head gasket.