JPH06200768A - Reed valve for two-cycle engine - Google Patents

Abstract

PURPOSE:To provide a reed valve for a two-cycle engine improving the responce of an engine, the high-speed rotation performance, and its durability by arranging a carbon fiber woven fabric prepreg at least on the outermost layer of a composite material, and setting the orientation direction of the fibers at a specific angle against the fixed end of the valve. CONSTITUTION:A reed valve used for a two-cycle engine mounted on a motorcycle or the like is made of a specific composite material. The specific material is formed with a multi-layer structure of the prepreg consisting of carbon fibers, and its thickness is set within the range of 0.1-1.0mum. The specific composite material is arranged with the carbon fiber woven fabric prepreg at least on the outermost layer 2 on an intermediate layer 1. The orientation direction of fibers of the prepreg is set at the angle of + or -45 deg. against the fixed end of the valve. The blowout of an engine is improved, the high-speed rotation performance is stabilized over a long period, and the reed valve excellent in durability against deformation vibration can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high power and lightweight reed valve valve for a two-cycle engine, which is applied to motorcycles, motorbikes, small boats, small generators, agricultural engines and the like.

[0002]

2. Description of the Related Art A two-cycle engine used for a motorcycle, a motorized bicycle, a small boat, a small generator, an agricultural engine, and the like has a process of inhaling and compressing a mixed gas of gasoline and air, ignition, explosion, combustion, Although the process of exhausting is repeated and output, the function of the reed valve that sucks the mixed gas and prevents the reverse flow influences its performance.

Conventionally, a steel plate spring material has been used as a reed valve valve of this kind. In recent years, however, the engine blows up well against a motocross or a high-performance competitive motorcycle, and a high rotational speed can be obtained. Although a performance engine is demanded, it is said that there is a limit to the performance improvement with the conventional steel leaf spring material.

[0004] Therefore, as a method for obtaining a favorable blow-up and a high-speed rotation of a two-cycle engine, a method of using a laminated plate made of a composite material of carbon fiber and an epoxy resin has been proposed in the past. A laminated plate of directional prepreg is used, or a laminated plate in which the direction of carbon fibers is oriented at 0 ° / 90 ° is used.

[0005]

However, in the case where the unidirectional prepreg laminate plate is used as described above, or the laminate plate in which the direction of the carbon fiber is oriented at 0 ° / 90 ° is used, the engine blows up, Although high-speed rotation performance was achieved, it was found that the reed valve valve was destroyed in a short time and could not be put to practical use except for special applications.

The present invention has been developed in view of the above circumstances, and its object is to improve the engine speed and the high speed rotation in a reed valve valve using a laminated plate made of a composite material of carbon fiber and epoxy resin. Naturally, it is to provide a valve for a reed valve that has excellent durability as well as performance.

[0007]

Means and Actions for Solving the Problems The present inventors have
In order to achieve these objects and obtain a high-performance two-cycle engine, the cause of damage to the lead valve valve was studied, and the mechanism was clarified and the present invention was reached. That is, when observing the movement of the valve attached to the reed valve with a high-speed camera, the vibration of the valve does not simply vibrate at the opening, but complicated deformation vibration accompanied by torsional deformation occurs, and the tip side surface is It was found that the valve was complicatedly hit against the opening of the valve and the damage progressed. The present inventors further examined the durability improvement by variously changing the orientation of the reinforcing fibers of the material, and found that the durability is significantly improved when the degree of orientation of the fibers is within a certain range, The present invention has been reached.

[0008] The gist of the invention is that the thickness of the prepreg having carbon fiber as a constituent fiber is 0.1.
In a 1 to 1.0 mm composite material reed valve valve,
At least in the outermost layer, arrange the carbon fiber woven prepreg,
A reed valve valve for a two-cycle engine, wherein the orientation direction of the fibers is arranged at an angle of ± 45 ° with respect to the fixed end of the valve. Epoxy resin is preferable as the matrix material of the prepreg.

According to the present invention, a lightweight, high-rigidity, high-impact-resistant reed valve valve can be obtained, so that the engine can be easily blown up, and long-term operation can be achieved even when the conventional high-speed operation of 150% is performed. The advantage is that it will be possible.

The reed valve used in the present invention uses an epoxy resin prepreg of a carbon fiber woven fabric or a carbon fiber unidirectionally aligned sheet as shown in FIG. 0 ° of seat, 9
By providing a 0 ° orientation layer and a ± 45 ° layer of a carbon fiber woven fabric as the outermost layer 2, a laminate of 3 to 5 layers is obtained, which is obtained by autoclaving or press molding.

The carbon fiber used is 20-30 Ton / mm ²
It is desirable that the high-strength carbon fiber has a modulus of elasticity of 1. Further, as the epoxy resin, a thermosetting epoxy resin having a heat resistance of 110 ° C. or higher can be used, and a toughness improver or the like can be used as necessary. It doesn't matter.

[0012]

EXAMPLES The present invention will be specifically described below with reference to examples.

Three plies of hand-woven carbon fiber woven fabric prepreg having a fiber content of 50% and the same diameter weft driving amount were prepared, and the intermediate layer was oriented and laminated so that the surface layer was 0 ° / 90 ° and the surface layer was ± 45 ° and heated. It was pressure-cured to obtain a plate-shaped body having a thickness of 0.3 mm.
When this plate was installed on the reed valve frame of a motorcycle two-cycle engine so that the outer layer fiber angle was ± 45 ° with respect to the fixed end face, an engine blow-up test was carried out, and extremely good results were obtained. The steel spring valve has a usage limit of 6,000 rpm, whereas the reed valve made of the carbon fiber prepreg multi-layer composite material of the present invention has a usage limit of 10,000.
It became possible to use it at a rpm for a long time of 100 hours or more.

For comparison, the fiber direction of the carbon fiber woven fabric is
With the outer layer being 0 ° / 90 °, the bending rigidity was set to be equal to that of the above-mentioned embodiment, and a composite material valve obtained by this was 10,000 rpm.
However, the durability was only 60 hours or less.

[0015]

As is clear from the above description, by using the reed valve valve of the present invention, the engine can be blown up well, and the conventional high speed rotation of 150% or more can be stably achieved for a long period of time. A two-cycle engine can be obtained, and a high-power horsepower can be obtained with the same weight and a light-weight two-cycle engine can be obtained with the same horsepower, and the technical and engineering contribution effect in the industry is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a reed valve valve according to the present invention.

[Explanation of symbols]

 1 Middle layer 2 Outermost layer

Claims (1)

[Claims] 1. A reed valve made of a composite material and having a thickness of 0.1 to 1.0 mm, which has a laminated structure of a plurality of prepregs having carbon fibers as constituent fibers, and a carbon fiber woven prepreg is arranged in at least the outermost layer, A reed valve valve for a two-cycle engine, characterized in that the orientation direction of is arranged at an angle of ± 45 ° with respect to the fixed end of the valve.