JPS593145Y2 - 2-cycle engine reed valve device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a reed valve device used to automatically check the supply air of a two-stroke engine such as a motorcycle or a light vehicle.

Conventionally, reed valves have been flat or V-shaped, and rubber has been baked onto one side of the engine crank chamber to provide an elastic valve seat to alleviate collisions between the reed valves.

However, the work of baking the rubber onto the base and the work of grinding it flat is difficult and time consuming, has a high incidence of defective products, and is expensive.

In order to solve this problem, the present invention replaces rubber by forming a pseudo-elastic body on the base itself.
The goal is to increase productivity.

As shown in FIG. 1, a synthetic resin base 3 is provided with a band-shaped protrusion 1 having a flat peak on the edge of the ventilation hole 2, and is attached to the band-shaped protrusion 1 so as to cover the ventilation hole 2 to control its opening and closing. It has a structure in which a control valve plate 5 made of a thin stainless steel plate and a stopper plate 6 that limits the lifting height of the valve plate 5 are successively stacked and fixed.

Instead of the conventional rubber surface, the top of the synthetic resin band-shaped protrusion 1 is made into a mountain shape, and the vicinity of the top surface, which acts as a valve seat, is thinned to reduce its rigidity, so that the band-shaped protrusion 1 acts as a pseudo-elastic body.

That is, since the seating portion of the base body 3 has a small area, even if it is made of a synthetic resin with a higher Young's modulus than rubber, the seating surface is sufficiently deflected, and the thin valve plate 5 is not easily seated. It can reduce the impact.

The band-like projection 1 is formed wide on one side, and a valve plate 5 and a stopper plate 6 are connected to the base body 3 by a through bolt 9 at the wide part.

Practically good results have been obtained when the cross section of the band-like protrusion 1, excluding one wide side, has a gentle mountain-shaped peak, that is, a so-called shogi barb shape, as shown in FIG.

The band-shaped protrusion 1 is formed into a mountain shape except for one wide side.

If a chevron is formed at the portion where the valve plate 5 and stopper plate 6 are fixed by the through bolt 9, the chevron may be deformed by the force of tightening the through bolt 9 and the seal may deteriorate. In order to increase the durability of the reed valve, it is preferable to eliminate the chevron shape on only one wide side as in this invention.

The synthetic resin base 3 is required to have a large heat insulating effect and oil and heat resistance, and thermosetting phenol resin satisfies these requirements while being inexpensive.

In addition, although the synthetic resin base 3 is not suitable for making fine screws due to its strength, it can be cut out freely, so a recess 8 for enclosing the nut is provided on the opposite side 7 of the crankcase. As shown in Figure 3, the through bolts 9 are used by applying a loosening material and tightening them repeatedly.

FIG. 4 shows an example in which the present invention is applied to a V-shaped substrate.

As described above, the present invention shows that by forming a pseudo-elastic body on the base, it is possible to prevent the valve plate from cracking and making noise, and to create an inexpensive reed valve device for a two-stroke engine, and this invention is made with a gap.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention, in which A in Fig. 1 is a plan view, the mouth is a central cross-sectional view, Fig. 2 is a vertical cross-section of the band-like protrusion of the invention, and Fig. 3 is a snap-locking portion. Enlarged sectional view of 4th
The figure shows another embodiment of the invention. 1...band-like projection, 2...ventilation hole, 3.
...Base, 4...Crankcase side, 5
...Valve plate, 6...Stopper plate, 7...
... Opposite side of the crankcase.

Claims (3)

[Scope of utility model registration request] (1) Ventilation holes 2 are provided in the base 3 made of synthetic resin, and ventilation (L
An annular band-like projection 1 whose top surface is formed on the same plane is provided on the periphery of the band-like projection 2, one side of the band-like projection 1 is formed wide, and a valve plate 5 is placed on the band-like projection 1 to control opening and closing of the vent hole 2. and a stopper plate 6 that limits the lifting height of the valve plate 5 are successively stacked and connected to the base body 3 at one wide side, and the top surface of the band-shaped protrusion 1 excluding the wide side is formed into a chevron shape. Reed valve device for 2-stroke engine. (2) A reed valve device for a two-cycle engine according to claim 1, in which a thermosetting phenolic resin is used as the synthetic resin base 3. (3) A reed valve device for a two-stroke engine according to claim 1, which is a utility model registration, wherein a recess 8 is provided on the opposite side 7 of the base body to the crankcase, and the valve plate 5 is attached with a through bolt 9.