JPS606056A - Cylinder head gasket - Google Patents

Abstract

PURPOSE:To prevent the deformation or breakage of dowel holes by trimming the peripheral edge of the dowel holes with grommets in a cylinder head gasket with dowel pins positioning the cylinder head and a cylinder block being penetrated. CONSTITUTION:A cylinder gasket 21 inserted between a cylinder head and a cylinder block is formed by using a thin metal plate or a metal net made of copper or steel as a core metal 22 and sticking asbestos 23 on both sides. The cylinder head gasket 21 is formed with multiple cylinder holes 24, water holes 25 passing the cooling water, bolt holes 28 through which head bolts are penetrated, and dowel holes 27 through which metal dowel pins are penetrated respectively. The peripheral edge of the cylinder holes 28 and dowel holes 27 is trimmed with grommets 28, 29.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a cylinder rad gasket interposed between a cylinder block and a cylinder head of an internal combustion engine.

[Prior art]

Generally, in an internal combustion engine, a cylinder head gasket is interposed between a cylinder block and a cylinder head to maintain airtightness and watertightness on the surfaces where these are assembled.

As a conventional cylinder rad gasket like this,
For example, there is one described in JP-A-57-13249. This cylinder head gasket is explained based on Fig. 1.2.■ is the cylinder head gasket, and the cylinder head gasket 1 has a core metal 2 made of a metal thin plate or wire mesh made of copper, steel, etc. It is molded by pasting asbestos 3 on it.

This cylinder rad gasket 1 is formed with a cylinder hole 4, a water hole 5 through which cooling water passes, a bolt hole 6 through which a head bolt is inserted, and a dowel hole 7 through which a metal dowel pin is inserted. has been done. The peripheral edge of the cylinder hole 4 is surrounded by a grommet (reinforcing ring) 8, which is made of metal such as copper or steel and is harder than asbestos 3.

On the other hand, the dowel hole 7 is formed by simply punching out a hole in the cylinder dowel gasket 1, and its peripheral edge is not hemmed with a groove. Further, a plurality of dowel holes 7 are formed, for example, one at each end of the cylinder head gasket 1, and the inner diameter thereof is approximately equal to the outer diameter of the dowel pin.

As shown in FIG. 2, such a cylinder rad gasket 1 is inserted between the cylinder block 9 and the cylinder head 10 when they are assembled, and its insertion position is accurately positioned by the dowel hole 7. Ru. 1. At this time, the assembly positions of the cylinder block 9 and the cylinder head 10 are also accurately determined by the dowel pins 11.

That is, the dowel pin 11 is inserted into the dowel holes 9a and 10a of the cylinder block 9 and the cylinder head 10 through the dowel hole 7 of the rad gasket 1 into the cylinder, and the assembly position of these and the insertion position of the rad gasket 1 into the cylinder are determined. accurately positioned.

However, in such a conventional cylinder door gasket 1, the dowel hole 7 was formed by simply punching out a hole in the cylinder door gasket 1, and therefore the temperature rise due to engine operation and stoppage was caused. When the cylinder head 10 repeatedly expands and contracts due to the lowering, and the Rad gasket 1 repeatedly moves together with the cylinder head 10 to the cylinder pressed by the cylinder head 10, the dowel hole 7 is easily deformed or damaged by the dowel pin 11. I end up. For this reason,
A phenomenon occurs in which the rad gasket 1 is deviated from the normal insertion position in the cylinder, and the grommet 8 at the peripheral edge of the cylinder hole 4 does not protrude into the combustion chamber, or the grommet 8 and the water hole 5 are cracked and damaged. As a result, gas, oil leaks, water leaks, etc. occur, and the operability of the engine deteriorates.

The above-mentioned problems occur particularly significantly in type II machines. That is, as shown in Fig. 3.4, in the V-shaped machine gap 12, the cylinder head gasket 1 and the cylinder head 14 are accurately connected to the respective cylinder blocks 13 of the left and right banks arranged in a V-shape via the dowel pins 11. It can be positioned and assembled. Note that 15 in FIG. 3 is a dowel hole formed in the cylinder block 13. In such a type machine [2], when the intake manifold 16, which is arranged to connect the left and right banks, thermally expands due to radiant heat etc. caused by the operation of the engine, the sod gas keso I-1 flows into the cylinder. When it is pushed outward together with the head 14 as shown by the arrow in Fig. 4 and contracted when the engine is stopped, the cylinder rad gasket 1 is left in place (that is, in the position where it was pushed outward). ■This phenomenon is repeated between models 12
In this case, the above-mentioned problems occur more conspicuously than in a series engine.

[Object of the Invention] Therefore, the present invention prevents deformation and damage of the dowel hole by edging the periphery of the dowel hole through which the dowel pin is inserted with a grommet, thereby preventing the displacement of the rad gasket to the cylinder. The purpose is to prevent water leaks and improve engine operability.

[Structure of the invention]

The cylinder head gasket according to the present invention is interposed between the cylinder head and the cylinder block, and
A dowel hole is formed into which a dowel pin for positioning these is inserted. The cylinder rad gasket is configured to prevent deformation and damage of the dowel hole by edging the peripheral edge of the dowell hole with a grommet.

〔Example〕

Hereinafter, the present invention will be explained based on the drawings.

Figure 5.6 shows an embodiment of the present invention.

First, to explain the structure, reference numeral 21 is a cylinder head gasket interposed between the cylinder head and the cylinder block. 22, and asbestos 23 is pasted on both sides. This cylinder head gasket 21 has a cylinder hole 24,
A water hole 25 through which cooling water passes, a bolt hole 26 through which a helen bolt is inserted, and a metal dowel pin
A plurality of dowel holes 27 are formed. The peripheral edge of the cylinder hole 24 has a grommet 2
The grommet 28 is made of a metal such as copper or steel and is harder than the asbestos 23. Further, the periphery of the dowel hole 27 is also bordered by a grommet 29, and like the grommet 28 of the cylinder hole 24, this grommet 29 is also made of metal such as copper or steel. As shown in detail in FIG. 6, the grooves 1-29 of this dowel hole 27 have a U-shaped cross section f, KL, and the entire peripheral edge of the dowel hole 27 is bordered. Further, both the upper and lower surfaces of the grommet 29 are coated with molybdenum disulfide, and the coating treatment makes the frictional resistance on both the upper and lower surfaces extremely small. One dowel hole 27 is formed at each end of the cylinder head gasket 21, and its inner diameter is equal to the diameter of the dowel pin glue.The dowel pins are inserted into these dowel holes when the cylinder head and cylinder block are assembled, and the The mounting position of the cylinder head gasket 21 is accurately determined by inserting a dowel pin into the dowel hole 27.

Next, the effect will be explained.

A dowel pin is fitted into the dowel hole of the cylinder block, and the dowel hole 27 of the cylinder head gasket 21 and the dowel hole of the cylinder head are sequentially fitted into the dowel pin to accurately position and assemble these three parts. When the cylinder head assembled in this way repeatedly expands and contracts as the temperature rises and falls due to engine operation and stop, the cylinder head gasket 21 moves from the cylinder head in the plane direction (that is, in the plane direction of the gas cylinder 21 to the cylinder). Receives movement force. Transfer the moving force of the Sodogasukesoto 21 to the cylinder through the dowel hole 27
The cylinder head gasket 21 itself is prevented from moving by acting as an abutting force on the dowel pin fitted into the cylinder head gasket 21 . The contact force acting on the dowel hole 27 from the dowel pin is applied directly to the grommet 29 provided at the periphery of the dowel hole 27.
Since the grommet 9 is made of metal and has durability, the contact directions are distributed around the periphery of the grommet 29. Additionally, since the upper and lower surfaces of the grommet 1-29 are coated to reduce the frictional resistance between the cylinder head and the grommet 29, the moving force that the peripheral edge of the dowel hole 27 receives from the cylinder head is reduced compared to the conventional method. It's extremely small. Therefore, the dowel hole 27 is prevented from being deformed or damaged, and the position of the cylinder 1-21 is prevented from shifting. As a result, it is possible to prevent oil, water, etc. from leaking into the cylinder due to misalignment of the gasket 21.

In addition, in a series engine in which cylinders are arranged in series, the degree of expansion and contraction of the cylinder head in the longitudinal direction of the series is particularly large. Therefore, in such a series engine, if a grommet is inserted into the dowel hole formed in the front-rear direction, the effect is effectively exhibited.

In addition, in a V-type machine in which the cylinders are arranged in a V-shape, the left and right banks are connected by an intake manifold, so in addition to the same effect as the above-mentioned series engine, the expansion and contraction of the intake manifold causes movement in the left and right directions. Misalignment of the gasket toward the cylinder often occurs, and oil and water leaks are more likely to occur than in series engines. therefore,
Providing a grommet in the dowel hole between such V-shaped machines has an extremely large effect.

〔effect〕

According to the present invention, by edging the peripheral edge of the dowel hole with a grommet, it is possible to prevent the dowell hole from being deformed or damaged, and it is possible to prevent the dowel hole from being displaced from the cylinder. As a result, it is possible to prevent oil and water leaks and improve the operability of the engine.

[Brief explanation of drawings]

Figures 1 to 4 are diagrams showing a conventional cylinder '\Sodogasukesoto. Figure 1 is a partial plan view thereof, Figure 2 is a sectional view taken along the nn arrow in Figure 1, and Figure 3 is a view of the cylinder. Diagram 4 showing the state when installing the Sodo Gas Soto between V-type machines.
The figure is a sectional view showing an example in which the cylinder is equipped with a gasket installed between V-type machines, Figure 5.6 is a view showing an embodiment of the cylinder cylinder according to the present invention, and Figure 5 is a plan view thereof. , FIG. 6 is a sectional view taken along the line ■-■ in FIG. 5. 2] --- Gasket to the cylinder, 27 ---
-Dowel hole, 29---grommet. Patent Applicant Nissan Motor Co., Ltd. Representative Patent Attorney Agagun Part Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] In a cylinder rad gasket that is interposed between a cylinder head and a cylinder block and has a dowel hole through which a dowel pin for positioning them is inserted, the periphery of the dowel hole is hemmed with a grommet. Characteristic cylinder head gasket.