JP2003232260A - Resin cylinder head cover for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin cylinder head cover for preventing an engine oil from entering thereinto. <P>SOLUTION: The resin cylinder head cover for an internal combustion engine comprises an oil resistant layer formed on the inward side thereof. The oil resistant layer is formed of, dominantly, thermoplastic polyurethane, polyester, polyvinyl fluoride, or rubber. In this construction, the engine oil is prevented from entering into a resin constituting the cylinder head cover and the changed size and reduced strength of the cylinder head cover due to the entry of the engine oil are suppressed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin cylinder head cover attached to an internal combustion engine. More specifically, it relates to reducing the amount of oil dipped in the resin cylinder head cover.

[0002]

2. Description of the Related Art In recent years, a cylinder head cover made of metal or resin has come to be adopted in response to the trend of weight reduction of automobiles and integral molding (modularization) of parts. A resin cylinder head cover made of a nylon resin is already known (Japanese Patent Publication No. 04-13596).

However, engine oil for reducing the frictional resistance of the camshaft and the like is present in the space between the cylinder head cover and the cylinder head that covers the engine. Under such a circumstance, if a cylinder head cover made of an oil-absorbing nylon resin is used, engine oil may be immersed in the cylinder head cover, which may cause a dimensional change of the cylinder head cover or a decrease in rigidity. .

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to prevent engine oil from immersing in a resin cylinder head cover even with a resin cylinder head cover.

[0005]

The invention according to claim 1 is
A resin cylinder head cover for an internal combustion engine, wherein a layer having oil resistance is formed on an inward side of the resin cylinder head cover for the internal combustion engine.

The invention according to claim 2 is a cylinder head cover characterized in that the layer having oil resistance in claim 1 is mainly composed of thermoplastic polyurethane, polyester, polyvinyl fluoride, or rubber. is there.

According to a third aspect of the present invention, the oil-resistant layer according to the first or second aspect is that the resin-made cylinder head cover includes an outer peripheral end portion of the resin-made cylinder head cover,
And a resin-made cylinder head cover for an internal combustion engine, wherein the resin cylinder head cover is fixed at a part on the inward side.

According to a fourth aspect of the present invention, in the invention according to the first to third aspects, the oil resistant layer is an inward side of the resin cylinder head cover, and the counterpart is in contact with the resin cylinder head cover. It is a resin cylinder head cover for an internal combustion engine, which functions as a sealing material of the.

[0009]

According to the first and second aspects of the invention, since the oil resistant layer is formed on the inward surface of the resin cylinder head cover, immersion of oil filling the cylinder head cover into the cylinder head cover is suppressed. .

According to the invention of claim 3, claim 1
Alternatively, in addition to the function of the invention according to claim 2, since the oil resistant layer and the resin cylinder head cover are fixed to the outer peripheral end of the resin cylinder head cover and a part of the inward side of the resin cylinder head cover, One or more thin closed spaces are formed between the resin cylinder head cover and the oil resistant layer. Then, the closed space thermally expands by the heat transferred from the engine while the engine is operating, and functions as a soundproof layer.

According to the invention of claim 4, claim 1
In addition to the effect achieved by the invention according to claim 3, the oil-resistant layer functions as a sealing material between the resin cylinder head cover and the mating member that contacts the resin cylinder head cover on the inward side. As a result, gaskets can be eliminated and assembly workability and the number of parts can be reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an assembling relationship of a resin cylinder head cover. The resin cylinder head cover 2 is formed long in the direction in which the pistons are arranged, and a flange portion 6 that abuts the cylinder head 4 is formed on the edge thereof.
Then, the resin cylinder head cover 2 and the cylinder head 4 are bolted to the flange portion 6 via a gasket 8.

FIG. 2 is a sectional view taken along the line AA of FIG. 1, showing a state in which the cylinder head 4 is assembled. The cylinder head 4 has an intake port 14, an exhaust port 16 and a combustion chamber 18. A cam 24 for opening and closing the intake valve 20 and the exhaust valve 22 in synchronization with the rotation of the internal combustion engine is installed on the upper surface of the cylinder head 4. The resin cylinder head cover 2 is assembled so as to cover the cam 24.

Reference numeral 30 in the drawing denotes a base material of a resin cylinder head cover, and the base material 30 is mainly made of nylon resin, but its strength is reinforced by SMC material or glass fiber. Can also be used. Reference numeral 32 denotes an oil-resistant layer formed on the inward side of the resin cylinder head cover 2. Here, the inward side is the side of the resin cylinder head cover 2 that faces the cylinder head 4. The oil resistant layer 32 is made of, for example, thermoplastic polyurethane, polyester, polyvinyl fluoride, polyimide, rubber, or the like, and is a material having oil resistance.

The oil resistant layer 32 prevents the base material 30 of the cylinder head cover 2 from coming into contact with oil. Therefore, even when the base material 30 is made of an oil-absorbing nylon-based resin or the like, it is possible to suppress immersion of oil in the base material 30. As a result, the strength reduction and dimensional change of the cylinder head cover 2 are suppressed.

The resin cylinder head cover 2 is manufactured by the following steps. First, after the base material 30 is injection-molded or compression-molded in the first step, the material 30 is injected into the mold without removing the base material 30 from the mold, and the inward surface of the base material 30 is injected. The oil resistant layer 32 is molded by a two-layer molding method. Further, after molding the base material 30, the base material 30 may be set in a mold different from the mold in which the base material 30 has been molded, and the material may be molded by a method of injecting any one of the above materials into the mold. As another method, a film forming method may be used in which after the base material 30 is formed, a material obtained by melting any of the above-mentioned materials 1 to 3 is sprayed on the inner surface of the base material 30 by a spray or the like to form the oil resistant layer 32. . Further, the base material 3
It may be formed by a method of separately molding 0 and the oil resistant 32 and adhering them with an adhesive, or by a welding method.

Further, the oil resistant layer 32 does not need to adhere to the entire surface of the base material 30 on the inward side of the base material 30. For example,
FIG. 3 is an enlarged view of the bonding surface between the oil resistant layer 32 and the base material 30. If the oil resistant 32 and the base material 30 are bonded (or welded) at several points 40 as shown in FIG. Good.
Then, the flange portion 6 of the resin cylinder head cover 2
If the oil resistant layer 32 is adhered to the base material 30 over the entire circumference and a thin closed space 44 is formed in the gap between the oil resistant material 32 and the base material 30, the closed space 44 thermally expands during engine operation. And functions as a soundproof layer.

Further, in this case, since the oil resistant layer 32 and the base material 30 are not in close contact with the entire surface on the inward side of the resin cylinder head cover 2, the oil resistant layer 32 can be easily removed from the base material 30. It can be desorbed and can be post-processed for each material at the time of recycling. Of course, even if it is not the adhesion method, since the oil resistant layer 32 has oil resistance, even if the oil resistant layer 32 is in close contact with the entire surface of the base material 30, the surface of the oil resistant layer 32 is cleaned. The oil adhering to the surface of the oil-proof 32 can be removed only by doing this. Therefore, when the resin cylinder head cover is recycled, the process of removing the oil that has penetrated into the resin in the recycling process is not necessary, or at least the oil can be easily removed, and the recyclability can be remarkably improved.

In FIG. 4, the contact portion between the cylinder head 4 and the resin-made cylinder head cover 2 is formed into a shape having sealing properties such as an uneven shape, and a rubber material or the like is selected as the material of the oil resistant layer 32. This is an example in which the oil resistant layer 32 has a function as a gasket.

The resin-made cylinder head cover can be easily formed into a complicated shape as compared with a metal cylinder head cover having a restricted shape, and thus the flange portion of the base material 30 can be easily formed. It is also possible to form the contact surface shape with the cylinder head to be uneven rather than simply flat. Even in such a case, the oil resistant layer 32 can be formed into the base material 30 by the above-mentioned two-layer molding or film molding.
It will be molded according to the shape of.

In this way, the oil resistant layer 32 can have a function as a gasket, so that the gasket 8 at the contact portion between the cylinder head 4 and the resin cylinder head cover 2 can be eliminated. Further, the oil resistant layer 32 can also perform the same function as a sealing material for a contact portion between the resin cylinder head cover 2 and a baffle plate (not shown) provided on the inward side of the resin cylinder head cover 2.

[0022]

As described above, in the inventions according to claims 1 to 4, the resin cylinder head cover is formed by forming the oil resistant layer on the inward side of the resin cylinder head cover. It is possible to prevent the oil from being dipped into the inside, and it is possible to prevent the dimensional change and the strength reduction of the cylinder head cover.

According to the invention of claim 3, in addition to the above effects, the closed space formed in the gap between the resin cylinder head cover and the oil resistant layer thermally expands and becomes a soundproof layer, so that noise emitted from the engine is reduced. Can be shut off.

Further, in the invention according to claim 4, since the oil resistant layer is also used as a sealing material for the abutting portion of the cylinder head and the resin cylinder head cover, the gasket can be eliminated and the cost can be reduced and the assembling work can be performed. The effect that the property is improved is exhibited.

[Brief description of drawings]

FIG. 1 is a view showing an assembling relationship between a cylinder head cover and a cylinder head.

2 is a cross-sectional view taken along the line AA in FIG. 1 in a state where a cylinder head cover and a cylinder head are assembled.

FIG. 3 is an enlarged view of a bonding surface between a cylinder head cover base material 4 and an oil / oil resistant layer.

FIG. 4 is an enlarged view of a contact portion between a cylinder head cover and a cylinder head. 2 ... Resin cylinder gasket, 4 ... Cylinder head,
6 ... Flange portion, 8 ... Gasket, 14 ... Intake port,
16 ... Exhaust port, 18 ... Combustion chamber, 20 ... Intake valve,
22 ... Exhaust valve, 24 ... Cam, 30 ... Base material, 32 ... Oil resistant layer, 40 ... Sticking point, 44 ... Closed space

Claims (4)

[Claims] 1. A resin cylinder head cover for an internal combustion engine, comprising an oil resistant layer provided on an inward side of the resin cylinder head cover for the internal combustion engine. 2. The resin for an internal combustion engine according to claim 1, wherein the oil-resistant layer of the preceding paragraph is mainly composed of thermoplastic polyurethane, polyester, polyvinyl fluoride, or rubber. Made cylinder head cover. 3. The oil-resistant layer according to claim 1 or 2 is fixed to a resin cylinder head cover at an outer peripheral end portion of the resin cylinder head cover and a part on an inward side. A resin cylinder head cover for an internal combustion engine according to claim 1 or 2. 4. The oil-resistant layer according to any one of claims 1 to 3, which functions as a sealing material on an inward side of the resin cylinder head cover with respect to an object that abuts against the resin cylinder head cover. A resin cylinder head cover for an internal combustion engine according to any one of claims 1 to 3.