JPS60211194A - Cylinder head cover of engine for motorcycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a cylinder cover made of a synthetic resin material in a motorcycle engine.

[Technical background of the invention and its problems]

When it comes to the engine of a four-wheeled motor vehicle, there is a
As shown in Japanese Patent No. 1941, a proposal has been made to mold the cylinder cover from synthetic resin to achieve weight reduction and soundproofing.

In motorcycles as well, it is desired that cylinder head covers be made of synthetic resin to reduce weight in order to save on fuel consumption.

However, when trying to mold a cylinder cover with synthetic resin, it is easily deformed due to curing distortion during molding, and the shape and flatness of the flange part, which should be airtightly joined to the cylinder head, is easily distorted. This results in a decrease in performance.

In order to prevent such distortion during molding, it is possible to form reinforcing ribs on the cylinder head cover, but if you try to prevent the distortion by using ribs, the ribs will become too stiff and the height of the cylinder head cover will increase. Increase. In the case of motorcycles, the fuel tank and frame are located above the engine, so if the rad cover is raised higher than the cylinder, it will interfere with the fuel tank and frame. Therefore, it is not preferable to form reinforcing ribs.

[Purpose of the invention]

An object of the present invention is to provide a rad cover for a synthetic resin cylinder of a motorcycle engine that maintains the opening edge in a predetermined shape without increasing the height of the rad cover and improves sealing performance. .

[Summary of the invention]

In order to achieve the above object, the present invention provides a cylinder with a cross section L
It is characterized by a continuous metal insert that is shaped like a letter and extends all around the circumference.

[Embodiments of the invention]

An embodiment of the present invention will be described below based on the drawings.

The motorcycle shown in Fig. 1 has a frame 1 with 2 cycles 4
It is equipped with a 2-cylinder twin-cam type engine. This engine 2 is of a so-called horizontal crankshaft type in which each cylinder is arranged side by side in the left-right direction.

A cover 4 is attached to the upper surface of the cylinder head 3, and a cam (not shown) for opening and closing an intake valve and an exhaust valve is provided in the space formed by the cylinder head 3 and the cover 4. A chamber is formed to accommodate the shaft (not shown). The respective camshafts are arranged side by side along the longitudinal direction of the vehicle body, and therefore the above-mentioned camshaft cover 4 has a second
As shown in the figure and FIG. 3, the camshaft housing portions 5, 5,
It has a connecting part 6 that connects these accommodating parts 5, 5, and has a figure 8 shape in plan view.

Incidentally, between the camshaft accommodating portions 5, 5 of the head cover 4 and the through hole shown in FIG. 2, an ignition glazer attached to the cylinder rod 3 faces out. Further, 8... indicates a vaporizer.

The structure of the above-mentioned bottom cover 4 is shown in detail in FIG. 3 and below. The head cover 4 is made of synthetic resin material.
Specifically, it is made of, for example, reinforced glass fiber-filled snylon by injection molding or compression molding. A flange capital 10 is formed at the opening edge of the head cover 4.

As shown in detail in FIGS. 6 and 7, a metal material 11 having an L-shaped cross section is inserted into the opening edge of the head cover 4 over the entire circumference of the opening edge. The vertical wall 12 of the metal material 11 is buried within the vertical wall, and the horizontal wall 13 is buried within the vertical wall 10. When the metal material 11 rises, the wall 1
2 has a plurality of through holes 14... in these through holes 14... when molding the head cover 4, a metal material 11 is embedded in the mold and a resin is inserted. When the material is injected, the molten resin material is flowing in. For this reason, the metal material 1 is integrally joined to the head cover 4.

In the seven-run section 10, the horizontal wall 13 of the metal material 11 has a surface facing the cylinder rod 3 exposed to the lower surface of the seven-run section 10, as shown by dashed diagonal lines in FIG.

In addition, in the 7-run section 10, the head cover 4
Zalt 1 used when connecting to cylinder head 3
The area where the head of the metal material 11 hits is indicated by broken diagonal lines in FIG. 3, and as shown in FIG. 7, the upper surface of the horizontal wall 13 of the metal member 11 is exposed. Therefore, the metal material 11 directly receives stress when the bolts 15 are inserted into the fixing holes 16, screwed onto the cylinder head 3, and tightened.

Note that 17 is a gasket that is held between the upper surface of the cylinder head 3 and the 7-run no. 10 of the head cover 4. This gasket 17 is made of, for example, asbestos.

The herad cover 4 of this embodiment having such a configuration is made of synthetic resin and is therefore lightweight. Moreover, since the metal material 11 is inserted into the edge of the opening of the spatula cover 4, sinking and warping during molding are prevented, and deformation during use is also prevented. In particular, since the metal material 11 has an L-shaped cross section, it prevents the deformation of the 7-run section 10 of the head cover 4 and the rising section connected thereto, and allows
Even if the pressure bar 4 has a complicated shape such as a letter shape, the shape of the opening edge is not deformed, and the flange portion 10
To maintain the flatness of an abutting surface of a flange part 10 with high precision without causing warpage or distortion. Therefore, when the gasket 17 is inserted and fastened with the delts 15, the clamping surface is maintained with high precision and the clamping pressure is distributed over the entire circumference, so that high sealing performance is maintained.

Also? The tightening force transmitted through the head of the seat 15 is directly supported by the metal material 11, and the lower surface of the metal material 11 directly presses the gasket 17, so the flange portion 10 of the head cover 4 is deformed. There's no risk of getting hurt.

For this reason, there is no need to attach a special reinforcing lip to the head cover 4, and the dimensions of the head cover 4 do not increase, so there is no fear of interference with the fuel tank 9 in Fig. 1, etc., and the layout of the parts of the motorcycle can be improved. It gets easier.

Furthermore, since the head cover 4 is prevented from being deformed by the metal material 11, it is possible to use a heat-resistant synthetic resin material for the head cover 4 even if it has a high shrinkage rate. Thermosetting resins such as BMC, phenol composites, and P, P, POM, PE
It is also possible to use materials with low raw material costs, such as thermoplastic resins such as T and PBT.

Similarly, since the shape of the flange surface is maintained with high precision, an inexpensive gasket made of asbestos can also be used as the gasket 17.

Note that the present invention is not limited to the engine 2 of the above embodiment, and is not particularly limited to the twin cam type, so the shape of the head cover 4 is not limited to the L-shape in plan view.

〔Effect of the invention〕

According to the present invention as described above, when a Rad cover is resin-molded into a cylinder made of synthetic resin, deformation does not occur because the metal material inserted at the edge of the opening prevents curing distortion. In particular, since the metal material has an L-shaped cross section and is continuous all around, the flange portion of the head cover can be kept in a highly accurate shape, thereby maintaining high sealing performance.

Therefore, there is no need to provide a reinforcing lip on the head cover, and the size of the head cover does not increase, so there is no fear that it will interfere with other parts of the motorcycle.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, in which Fig. 1 is a side view of a motorcycle, Fig. 2 is a top view of the engine, Fig. 3 and subsequent figures show a cylinder head cover, Fig. 3 is a top view, and Fig. 4 is a side view of the motorcycle. is a cross-sectional view taken along line ■-■ in Figure 3, Figure 5 is a bottom view, and Figures 6 to 8 are cross-sectional views taken along line ■-■, line ■-■, and line ■-■ in Figure 3, respectively. It is. DESCRIPTION OF SYMBOLS 1...Frame, 2...Engine, 3...Cylinder head, 4...Cylinder rad cover, 9...Fuel tank, 10...Flange part, 11...Metal material, 14
Kawa Toukou, 15...? Ruto, 17...Gasket. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] A metal material having an L-shaped cross section is continuously inserted around the entire circumference of the opening edge of the cylinder head cover made of synthetic resin material, over the flange portion and the rising portion thereof. Rad cover for the cylinder of a motorcycle engine, which is characterized by: