JPH0543329Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to reeds used in reed valves, and in particular, to reeds used in reed valves that use metal-resin composite materials with excellent responsiveness and durability. Regarding.

[Prior art and its problems]

Generally, reed valves for two-stroke engines use metal reeds, but the reeds have poor responsiveness in the medium speed range and tend to reduce horsepower. In order to cope with this, attempts have been made to reduce the weight of the lead material and to use resin-based leads.

As shown in FIGS. 3a and 3b, the resin-based lead 10 conventionally used is made into a cloth by plain weaving or satin weaving glass fibers, carbon fibers, etc., and this cloth is made of epoxy resin, imide resin, etc. After obtaining prepreg by impregnating the prepreg, a plurality of sheets of this prepreg are stacked, heated and pressurized to form a plate, and then this plate is punched into a predetermined shape.

However, in the case of the conventional lead 10,
When punching the reeds, small cracks and peeling between the prepreg layers occur on the reed end face, which gradually becomes larger when the reeds are opened and closed, eventually leading to damage to the reeds and reducing the durability of the reed valve. It had

Another problem, especially with two-stroke outboard engines, is that when idling,
In order to ensure efficient and smooth operation, the ignition timing may be delayed from the original timing.
At this time, a so-called backfire phenomenon occurs in which combustion continues until the suction process, and the vicinity of the suction port becomes high temperature, and in the case of reed valves that use resin-based reeds, the reed part is heated, causing separation between the prepreg layers. , which had problems that led to damage to the reed valve.

The present invention solves the problems of the conventional ones as described above, and provides a reed for use in a reed valve that has excellent responsiveness and durability, and is less likely to be damaged by the backfire phenomenon. The purpose is to

[Means for solving problems]

In order to solve the above problems, the present invention has a structure in which a lead body is formed by laminating a plurality of prepregs made of resin and fibers, and the peripheral end surface of this lead body is coated with a thin metal film. are doing.

[Effect]

By adopting the above structure, the present invention has a response comparable to that of conventional resin-based leads, has excellent durability, and is also resistant to damage due to the backfire phenomenon. .

〔Example〕

Embodiments of the present invention shown in the drawings will be described below.

FIG. 1 shows an embodiment of a reed valve using the reed of the present invention, and this reed valve 1
In this example, a lead 4 having a metal thin film 4b disposed on the peripheral end surface of a lead body 4a made of resin and fiber, and a stopper 5 are attached to a case complete 3 equipped with a seating member 2 made of an elastic material such as rubber. It is configured by attaching it with screws 6.

FIG. 2 shows the lead body 4a and the metal thin film 4b.
A lead 4 of the present invention is shown, and FIG. 2a is a plan view of the lead 4, and FIG.
2 is an explanatory cross-sectional view of the lead 4 shown in FIG. 2, in which a metal thin film 4b is disposed on a peripheral end surface of a lead body 4a, that is, a portion of a tip end surface and a side end surface of the lead body 4a. It is.

The lead 4 shown in the figure is first made into a cloth by plain weaving or satin weaving glass fiber, carban fiber, etc.
After impregnating this cloth with epoxy resin, imide resin, Kevlar resin, etc. to obtain prepreg, multiple sheets of this prepreg are stacked, heated and pressurized to form a plate, and this plate is punched into a predetermined shape. Lead body 4
get a.

Next, a metal thin film 4b is formed on a predetermined portion of the lead body 4a by at least one method selected from chemical plating, electroplating, vacuum deposition, sputtering, ion plating, and chemical vapor deposition.

In the lead 4 configured as described above, the lead body 4a is formed by laminating a plurality of prepregs made of resin and fibers, so the natural frequency is high and the spring constant is low, resulting in poor response. In addition, since the peripheral end surface of the lead body 4a is covered with the metal thin film 4b, the weight remains almost the same and the above-mentioned functions are not impaired. Cracks in the parts and peeling between the prepreg layers are prevented, and durability is greatly improved, and damage to the leads 4 due to the backup fire phenomenon is extremely small.

[Effect of idea]

The present invention is configured as described above, and the lead body is formed by laminating multiple prepregs made of resin and fibers, so the natural frequency is high and the spring constant is low, resulting in improved response. Also, since the peripheral end surface of the lead body is coated with a thin metal film, the above function is not impaired, and further,
This resin significantly improves durability by preventing cracks on the peripheral edge of the reed body and peeling between the prepreg layers due to impact when the reed opens and closes, and has a high natural frequency and low spring constant. It has the excellent effect of improving the durability of the lead by preventing cracks on the peripheral edge of the lead and peeling of the prepreg layers due to impact during the opening and closing operation of the lead, while maintaining the characteristics of the lead. be.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of a reed valve using the reed of the present invention, Fig. 2 shows the reed according to the invention, Fig. 2a is a plan view of the reed, and Fig. 2b is a cross-sectional view of the reed valve according to the present invention. FIG. 3 shows a conventional lead, FIG. 3a is a plan view of the lead, and FIG. 3b is a cross-sectional view of what is shown in FIG. 3a. 1... Reed valve, 2... Seating member, 3...
Case complete, 4,10...lead, 4a
...Lead body, 4b...Metal thin film, 5...Stopper, 6...Mounting screw.

Claims (1)

[Scope of utility model registration request] The lead body 4a is formed by laminating a plurality of prepregs made of resin and fibers, and the lead body 4a is
A reed for use in a reed valve, characterized in that the peripheral end face of a is coated with a metal thin film 4b.