JP2002089382A - Reed valve device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reed valve device capable of satisfying the operability at a low speed and the following ability at a high speed by improving the function as a reed valve for a compact engine to be mounted on a model helicopter and durable in the long time use by improving the durable service life of a reed valve plate. SOLUTION: This reed valve device for engine has a reed valve body having a valve port and the reed valve plate having a base end part fixed to the reed valve body in the condition that the reed valve plate covers the valve port, and this reed valve device is fitted to an intake air passage of an engine so that the reed valve plate opens and closes the valve port with the operation of the engine. The reed valve plate is made of the raw material mainly composed of the polyether ether ketone resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reed valve device which is provided in an intake passage of an engine and opens and closes according to the operation of the engine.

[0002]

2. Description of the Related Art In a two-stroke engine or the like, a reed valve that opens and closes in accordance with the operation of an engine is provided in an intake passage communicating with a crankcase or the like of the engine, and intake is performed via the reed valve. Things are generally known. As another intake system for a two-cycle engine, there is also known an intake system in which intake is performed via a rotary valve that rotates in synchronization with the engine. It is difficult to change the opening / closing timing according to the condition, and it is not always possible to obtain the opening / closing timing suitable for various operation states.
On the other hand, the reed valve opens and closes in response to pressure fluctuations in the crankcase and the like, and opens and closes in a timely manner in accordance with the engine speed and the like.

The reed valve device has a reed valve body having a valve port, and a reed valve plate having a base end fixed to the reed valve body so as to cover the valve port. The reed valve body is fixed to the intake passage communicating therewith.

[0004] In such a reed valve device, for example, an improvement in followability and durability has been proposed, for example, in Japanese Utility Model Application Laid-Open No.
As shown in Japanese Patent Application Laid-Open No. 2-190175, the reed valve plate is made of resin, the tip of the reed valve plate abutting on the valve seat at the distal end of the valve port is formed thick, and the base end of the reed valve plate is formed. Some parts are thin-polished from the part to the thick part. According to this reed valve device, it is emphasized that most of the reed valve plate is made thinner and lighter, so that responsiveness is improved and damage to the tip portion of the reed valve plate that contacts the valve seat is also suppressed. .

In this type of reed valve device, it is necessary to satisfy the responsiveness and followability to the operation of the engine from the low speed range to the high speed range of the engine. Especially when applied to small model engines such as model helicopters and model airplanes, smooth operation at low speed to secure low speed performance and improve torque follow-up performance to improve high-speed followability It is required to increase the number of revolutions to, for example, about 15000 rpm or more, but the following problems remain for such a demand.

That is, since the suction negative pressure acting on the reed valve plate is relatively small when the engine is running at a low speed, it is preferable to form the reed valve plate thin and flexible in order to operate the reed valve properly at a low speed. However, if you do this,
Since the opening / closing operation speed of the valve increases as the suction negative pressure increases at the time of high-speed operation of the engine, the so-called waving occurs in which the reed valve plate bends and deforms in a wave-like manner during operation, resulting in poor followability and a delay in opening / closing operation. The air-fuel mixture blows back and the engine output cannot be increased. As a result, it becomes difficult to increase the limit rotational speed. On the other hand, in order to suppress such undulations and improve the followability at high speeds, the reed valve plate must be thickened to strengthen the stiffness. The board is difficult to open, and low-speed performance is impaired.

As described above, when the conventional reed valve device is used in a wide rotational speed range, it is difficult to achieve both low-speed operability and high-speed follow-up performance. However, such a structure cannot sufficiently solve the problem. Recently, FRP has been used as a material for reed valves.
(Fiber reinforced plastic) has been developed to improve the followability, etc., but even with FRP, the limit rotation speed is up to about 15000 rpm, and in the case of a small model engine, the limit rotation speed is further increased. An increase in numbers is required.

Therefore, the present inventor can operate smoothly even at a low speed where the suction negative pressure is small to secure a low speed performance.
In addition, research has been conducted in advance of the development of a reed valve device for an engine capable of improving the followability at high speeds and increasing the limit rotational speed, and has been studied in advance, and has been disclosed in Japanese Patent Application Laid-Open No. 9-209768. A valve device was proposed.

The characteristic structure of the reed valve device disclosed in this publication is that the structure of the reed valve plate is devised. The reed valve plate has a low rigidity at the distal end side, and the rigidity gradually increases from the distal end to the intermediate portion. It is formed so that it becomes high, and the middle part and the part near the base end become more rigid, and the rigidity near the base part becomes lower than the middle part.
Improvements in structure have made it possible to achieve both low-speed operation and high-speed tracking.

The present inventor has been conducting research with a view to further improving the reed valve device. However, this time, the present inventors have repeatedly studied particularly the material of the reed valve plate. That is, since the reed valve plate repeatedly opens and closes at a high speed exceeding 15,000 rpm at the time of high-speed operation as described above, it is required to have durability capable of maintaining appropriate elasticity and rigidity for a long period of time even under such severe use conditions. However, metal reed valve plates (stainless steel, phosphor bronze, beryllium copper, etc.) used in general reed valve devices have excellent heat resistance, but are susceptible to fatigue deterioration due to high-speed operation, and are relatively short-lived. It loses elasticity in a while and loses its function as a reed valve plate. Further, in the above-described FRP reed valve plate, damage to the tip portion in particular rapidly progresses due to repeated impacts due to the high-speed opening / closing operation, and a satisfactory durability life cannot be obtained.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has as its object to improve the reed valve plate particularly from the viewpoint of the material, thereby improving the operability at low speeds and the high speed. It is an object of the present invention to provide a reed valve device that satisfies both the time followability and has a good durability life and can withstand long-term use.

[0012]

According to the present invention, there is provided a reed valve device having a reed valve body having a valve opening and a reed valve body having a base end covered with the reed valve body. A reed valve plate fixed to the reed valve plate, the reed valve device being attached to an intake passage of an engine, wherein the reed valve plate opens and closes a valve port as the engine operates. The gist is that the valve plate is formed of a material mainly composed of polyetheretherketone resin.

The above-mentioned reed valve plate is made of a polyetheretherketone resin (hereinafter referred to as PEEK) which is a main constituent material thereof.
The abbreviated characteristics of the reed valve plate, regardless of the shape and structure, will provide a more durable life than conventional reed valve plates made of metal or FRP. In order to make more effective use, it is also effective to devise the shape and structure of the reed valve plate.For example, the rigidity of the reed valve plate at the distal end side is low as previously proposed, and the rigidity gradually increases from the distal end to the middle portion. The intermediate portion and the portion closer to the base end than this have high rigidity, and are formed so that the rigidity is lower than the middle portion near the base end portion. Select the PEEK material if the thickness gradually increases to the middle part, the middle part and the part closer to the base end become thicker, and a low rigidity part with reduced rigidity is provided near the base end. Together with use,
It is preferable because the reed valve device has excellent performance in low-speed operation and high-speed followability, and has a remarkably excellent durability life.

[0014] Such excellent operability, followability and durable life require a particularly high limit engine speed among engines, and small model engines such as model helicopters and model airplanes with large fluctuations in high speed and low speed. Particularly, it is effectively exhibited by applying to a two-cycle engine or the like.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present inventor has set forth a reed valve plate for use in a small engine for a model helicopter or a model airplane under particularly severe conditions under the above-mentioned problems. We studied repeatedly from the viewpoint of material.

The characteristics required of the constituent material of such a reed valve plate include: 1) a material having both appropriate rigidity and elasticity (a physical material capable of achieving both low-speed operability and high-speed followability); Characteristics, more specifically, for example, 16000
It has physical characteristics that can adapt to a wide open / close operation cycle that can follow high-speed opening / closing operations such as rpm, and can be smoothly applied to low-speed opening / closing operations.) Typically, 1
3) Excellent oil resistance and chemical resistance (Synthetic oil and castor oil contained in fuel, and not affected by methyl alcohol, nitromethane, etc.) 4) It should be excellent in hydrolysis resistance (it should not be deteriorated by hydrolysis due to high temperature moisture generated by combustion), 5) It should be easy to obtain and excellent in processability (That can be easily processed according to the size and shape of the reed valve plate, etc.).

The characteristic 1) described above is an essential characteristic required as a reed valve plate for a small engine such as a model helicopter such as a model helicopter which has a very high required rotational speed and a large cycle variation from low speed to high speed. The characteristics 2) to 4) above are extremely important in increasing the durability life of the reed valve plate, and the characteristics 5) above are implemented on a practical scale as a reed valve plate from the viewpoint of material and workability. This is an indispensable requirement for realizing.

The present inventor has sought a material capable of satisfying all the above-mentioned required characteristics, and has been working on a large number of materials, including metals and plastics, and engineering plastics, which are attracting attention as relatively new materials. With respect to the material, the required performance as a reed valve plate was repeatedly examined.

Then, from among a number of materials, materials shown in the following Table 1 are first selected as materials satisfying the required characteristics of the above 1), and the required characteristics of the above 2) to 5) are included for each of the selected materials. The characteristics as a reed valve plate for a high-speed cycle engine were examined in detail, and the results shown in Table 1 were obtained.

The respective evaluation experiments shown in Table 1 below were performed as follows.

[General performance] Each test piece (0.4 m thick)
m × width 17.5 mm × length 18 mm) was evaluated by the following method.

Chemical resistance and oil resistance: Each test piece was immersed in a fuel oil containing methyl alcohol, nitromethane and castor oil at room temperature for 60 days. What was done was evaluated as x.

Hydrolysis resistance: Each sample piece was immersed in water at 25 ° C. for 60 days. A sample having no dimensional change was rated as ○, and a sample having dimensional change was rated as x.

Rigidity and elasticity: Based on a GFRP test piece, those that were equivalent to this were rated as △, and those that were better than this were rated as ○.

Heat resistance, heat-resistant sustaining temperature: heat-resistant temperature is 140
A temperature of less than ° C was evaluated as x, and a temperature higher than 0 ° C was evaluated as ○.

Formability: The ease of press forming and finishing was comprehensively evaluated in consideration of the availability of the raw material itself.

[Practical performance] Using each material, a test piece of a reed valve plate having the same size as above (thickness: 0.4 mm × width: 1)
7.5 mm x 18 mm in length), each was incorporated into an engine performance tester, and a performance evaluation experiment was performed at 18000 rpm x 30 minutes. The performance when a GFRP test piece was used was taken as a standard and equivalent to this. Those that were present were evaluated as ○, those that were inferior were evaluated as Δ, and those that were better than this were evaluated as ◎. Also, after the above test, the damage state of the reed valve plate was observed, and those which were in a state where they could not be reused due to the occurrence of cracks and deterioration in toughness were reusable life ×, cracks and deterioration in toughness were slight or hardly recognized and reusable Durable life of the state ○
Was evaluated.

Regarding the necessity of cushion rubber, a conventional reed valve plate requires a cushion material (usually made of nitrile rubber) between the valve plate and the valve port. The test was performed with the cushion rubber attached. However, it was confirmed that some of the reed valve plates could be put into practical use without cushion rubber, so experiments were conducted with and without cushion rubber on the reed valve plates of each material. Was evaluated as x, and those that could be used without cushion rubber were evaluated as ○.

[0029]

[Table 1]

As is clear from Table 1, the general performance of the metal reed valve plate is all good, but the practical performance is poor in both the valve performance and the durable life, and cannot be put to practical use without cushion rubber. In addition, resin-made reed valve plates made of polyacetal-based resin or polyamide-based resin have insufficient heat resistance and elasticity, resulting in insufficient valve performance. Reinforced plastics containing glass fiber or carbon fiber as a reinforcing material have insufficient moldability and valve performance. I can't get it.

Further, the polyethylene terephthalate resin is inferior in valve performance due to insufficient elasticity, and also has insufficient durability against heat and hydrolysis, which hinders the durability life. Typical polyimide resins with excellent heat resistance and strength properties have good general performance including heat resistance and heat resistance persistence, but have poor moldability and lack of resistance to repeated impacts. Performance and durability are not satisfactory. In addition, all of these resin reed valve plates must be used together with cushion rubber to absorb impact.

On the other hand, among the resin-made ones, PEE
Only K satisfies all general performances including elasticity, heat resistance, heat resistance durability, moldability, etc., and also shows excellent performance in valve performance and durability life. And PEEK
Reed valve plate has excellent impact resistance, so it shows sufficient durability without the use of cushion rubber, and the cushion rubber, which was conventionally required, can be omitted. It can be seen that the material is very excellent.

The preferred physical properties of the PEEK used in the present invention include a crystallinity of 30 to 40% and a tensile strength of 9%.
5 to 100 MPa (ISO R527 method: 50 mm / m
in, normal temperature) and a tensile modulus of 3-4 GPa (ISO R
527 method, normal temperature), the flexural modulus is 4 to 4.5 GPa (I
SOR178, room temperature), flexural strength 160-200M
Pa (ISO R178 method, normal temperature) and a glass transition temperature in the range of 140 to 150 ° C. PEEK satisfying such physical properties can be obtained, for example, under the trade name “PEEK ^™ 450P” manufactured by Victrex MC Corporation. .

These PEEK materials can be obtained as plate-like or rod-like extruded materials, or can be obtained as pellets or powders that can be injection-molded or extruded. These PEEK materials may be those of PEEK alone containing substantially no other components, or may be those obtained by compounding an appropriate amount of reinforcing fibers or fine powder if necessary. Of course, a small amount of the above additive may be included.

As described above, the present invention is characterized in that a material mainly composed of PEEK is used as a reed valve plate.
It has a feature in that the above-mentioned features of EEK are effectively reflected in the performance as a reed valve plate. Therefore, the shape and structure of the reed valve plate are not particularly limited. In order to further enhance the practical performance as a valve plate, it is also extremely effective to add the above-described measures. Therefore, a preferred shape and structure of a reed valve plate will be described below.

That is, as a preferable shape and structure of the reed valve plate, the rigidity at the distal end side is low and the rigidity gradually increases from the distal end to the intermediate portion, and the rigidity is high at the intermediate portion and the portion closer to the proximal end than this. In the vicinity of the base end, it is preferable that the base is formed so as to have lower rigidity than the intermediate part.

With such a configuration, the distal end of the reed valve plate is flexible, and the distal end of the reed valve plate can be easily opened and closed in accordance with the pressure fluctuation even at a low engine speed where the suction negative pressure is small. When the engine is running at high speed,
The vicinity of the base end is largely bent in response to the suction negative pressure, and substantially the entire reed valve plate is opened and closed. However, the rigidity of the intermediate portion of the reed valve plate is structurally increased, and the rigidity of the PEEK itself is increased. Together with this, it is possible to suppress the reed valve from being bent in a wave shape or the like during operation, and the followability is improved.

As means for specifically utilizing such shape characteristics, the reed valve plate is formed such that the thickness of the reed valve plate at the distal end side is small and the thickness gradually increases from the distal end to the intermediate portion. What is necessary is just to form so that the part near the end becomes thick and has a low-rigidity part in the vicinity of the base end in a shape with reduced rigidity.

The low-rigidity portion near the base end of the reed valve plate is formed, for example, by providing a groove extending in the width direction of the reed valve plate, or by providing a hole near the base end of the reed valve plate. Alternatively, it can be formed by providing a notch near the base end of the reed valve plate.

Hereinafter, the shapes and shapes preferably employed in the present invention will be described.
An embodiment from a structural aspect will be described with reference to the drawings,
The present invention is not necessarily limited to the illustrated examples below,
In short, any material using a PEEK-based material as a reed valve plate is included in the technical scope of the present invention.

FIG. 1 shows a state in which a reed valve device according to an embodiment of the present invention is incorporated in a two-stroke engine. In FIG. 1, reference numeral 1 denotes a crankcase of a two-stroke engine, and reference numeral 2 denotes an intake passage opening to the crankcase. A carburetor 3 is mounted upstream of the intake passage 2. Downstream of the carburetor 3, a reed valve 5 is incorporated in the intake passage 2.

As shown in FIG. 2, the reed valve 5 includes a reed valve body 6 and a pair of reed valve plates 10 made of a material mainly composed of PEEK. The reed valve body 6 has a substantially V-shaped cross section, a valve port 6a is formed on both inclined wall portions, and a flange portion 6b is formed on the base end side.
The flange portion 6b is attached to a passage wall of the intake passage 2 with a bolt 7 or the like. Further, the pair of reed valve plates 10 are located outside both inclined wall portions of the reed valve body 6, and the base ends are attached to the reed valve body 6 with screws 8 or the like while covering the valve port 6a. I have. Reference numeral 81 denotes a screw insertion hole provided at the base end of the reed valve plate 10, and reference numeral 82 denotes a screw hole provided in the reed valve body 6.

In the example shown in FIG. 2, the reed valve 5 is a six-leaf type. In other words, three valve ports 6a are provided side by side on both inclined wall portions of the reed valve body 6, and correspondingly, the pair of reed valve plates 10 correspond to three pieces arranged in parallel, respectively. Are connected at the base end.

A stopper 9 is formed on an inner wall surface of the intake passage 2 at a position corresponding to each piece of the reed valve plate 10.

The reed valve plate 10 has a low rigidity at the distal end side and gradually increases in rigidity from the distal end to the intermediate portion, and has a predetermined high rigidity in the intermediate portion and a portion closer to the proximal end than the intermediate portion. In the vicinity, it is formed so as to have lower rigidity than the intermediate portion. In this embodiment, the reed valve plate 10
Is made of PEEK, and the rigidity is changed as described above by changing the thickness of each part as shown in FIG.

That is, in a portion 11 (hereinafter, referred to as a tip portion) of the reed valve plate 10 which is on the tip side from a predetermined position, one surface (front side) is an inclined surface, so that the thickness of the tip is reduced. The thickness is gradually changed so that it is the thinnest and has the maximum thickness at a predetermined position in the middle portion. Further, a portion 12 (hereinafter, referred to as a base portion) which is closer to the base end than a predetermined position of the intermediate portion and excluding the vicinity of the base end.
(Referred to as a portion closer to the base end), the thickness is substantially constant corresponding to the maximum thickness. A low-rigidity portion is formed in the vicinity of the base end by providing a groove 13 having an arc-shaped cross section extending in the width direction of the reed valve plate.

The portion of the distal end portion 11 close to the distal end is supple enough to bend sufficiently in the valve opening direction even at a relatively low negative pressure during idling operation of the engine. The material of the reed valve plate and the thickness of each part are set so that the skew portion 12 has sufficiently high rigidity.

As described above, the operation of the reed valve device which is devised in terms of shape and structure will be described. During operation of the engine, the pressure in the crankcase fluctuates according to the vertical movement of the piston and the like. , The reed valve plate 10 opens and closes. That is, the reed valve plate 10 is opened when the pressure inside the crankcase 1 becomes negative (see FIG. 4), and closed when the pressure inside the crankcase 1 increases.

When the engine is running at a low speed, the suction negative pressure acting on the reed valve plate 10 is small, but the tip portion 11 of the reed valve plate 10 is thinner at the tip, and the portion near the tip is flexible. Therefore, the tip end portion 11 is bent in the valve-opening direction even by a small suction negative pressure at the time of low-speed rotation (two-dot chain line in FIG. 4), and the opening / closing operation according to the pressure fluctuation is favorably performed. .

As described above, when the suction negative pressure is small, the distal end portion 11 mainly bends, but the low-rigidity portion near the base end where the groove 13 is formed also bends to some extent according to the suction negative pressure. As the suction negative pressure increases, the degree of bending near the base end increases.

During high-speed rotation, a large suction negative pressure acts on the reed valve plate 10 so that the low-rigidity portion near the base end is largely bent, and substantially the entire reed valve plate 10 contacts the stopper 9. (See the solid line in FIG. 4), and substantially the entire reed valve plate 10 opens and closes in response to pressure fluctuations. In this case, at the time of high-speed rotation, the suction negative pressure increases and the reed valve plate 10 opens and closes at a high speed. Therefore, if the reed valve plate 10 is flexible, the reed valve plate 10 bends and deforms in a so-called wavy state during operation. Therefore, the ability to follow the operation of the engine is deteriorated.
The zero proximal portion 12 is thick and has sufficiently high rigidity, so that the waving state is suppressed and the followability is improved.

Further, in the reed valve plate 10 using PEEK as a constituent material, the excellent rigidity and elasticity of the PEEK material can improve the followability while suppressing the waving state, and furthermore, provide excellent heat resistance. Resistance, heat resistance, impact resistance, chemical resistance, oil resistance, and hydrolysis resistance prevent fatigue deterioration that tends to concentrate on the tip 11 and groove 13 of the reed valve plate 10 due to high-speed repetitive opening and closing operations. , Indicating an outstanding durability life.

As described above, according to the reed valve device of the above-described embodiment using the reed valve plate 10 made of PEEK material, the operability at low speed rotation is maintained and the followability at high speed rotation is improved. Thus, the limit rotational speed of the reed valve 5 is greatly increased. The inventor has confirmed experimentally that a conventional reed valve (for example, a reed valve plate
In the reed valve device having the structure shown in the above embodiment and using a reed valve plate made of PEEK, the critical rotation speed was 15,000 rpm or less in the case of the one formed by RP to have a constant thickness. 20,000 rpm limit speed
It has been confirmed that a material that can withstand high-speed rotation of more than that obtained is obtained.

In the apparatus of the present invention, the reed valve 5
Is not limited to the six-leaf type as shown in the above embodiment, and may be a two-leaf type in which a pair of reed valve plates are provided with one piece,
A four-leaf type or the like in which individual pieces are provided may be used, but increasing the number of leaves is advantageous for improving followability.

In the above embodiment, a groove 13 having an arc-shaped cross section is formed as a low-rigidity portion provided near the base end of the reed valve plate 10, but a V-shaped groove 13 as shown in FIG.
1, grooves having various cross-sectional shapes such as a rectangular groove 132 as shown in FIG. 6 can be employed. In addition, instead of such a groove, a hole having an arbitrary shape such as a window hole 133 as shown in FIG. 7 or a round hole 134 as shown in FIG. As shown in FIG. 9, a low rigidity portion may be formed by providing a cutout 135.

In the above-described embodiment, the front surface side is formed as an inclined surface, but the back surface side or both the front and back surfaces may be formed as an inclined surface so that the thickness of the front end portion 11 of the reed valve plate 10 is gradually changed. Instead of such an inclined surface, a gentle curved surface or a step-like surface may be formed on one or both surfaces.

In the above-described embodiment, the portion 12 near the base end of the reed valve plate 10 has a substantially constant thickness. However, as shown in FIG. The proximal portion 121 may be formed so that the thickness becomes gradually thinner. Also, as shown in FIG. 11, the thickness gradually increases from the distal portion 11 to the proximal portion 122 as it approaches the vicinity of the proximal portion. It may be formed as follows.

As a structure for increasing the rigidity of the portion close to the base end and gradually changing the rigidity at the distal end portion, instead of changing the wall thickness as in the above embodiment, a rib is provided and the protrusion is provided. The amount, arrangement, and the like may be changed in each unit.

When the reed valve device of the present invention is applied to a small two-stroke engine used in a model helicopter, a model airplane, or the like, it is possible to secure a low-speed performance and increase torque by increasing a limit rotation speed. Although excellent effects can be obtained in such points as possible, such features can also be utilized in two-cycle engines such as motorcycles, and even four-cycle engines etc. provided that a reed valve is provided Applicable.

[0060]

The present invention is constructed as described above, and PEEK is used as a constituent material of a reed valve plate in an engine reed valve device, and it is preferably devised as described above also in view of its shape and structure. As a result, it is possible to increase the limit rotation speed while securing the low-speed performance of the engine, and to extend the durability life of the engine. Further, according to the present invention, by using a PEEK-based reed valve plate, it is possible to omit the cushion rubber, which is conventionally required, and accordingly, troubles caused by cracking or deterioration of the cushion rubber can be achieved. Can also be eliminated.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a state in which a reed valve device according to an embodiment of the present invention is assembled to an intake passage in terms of shape and structure.

FIG. 2 is an exploded perspective view of a reed valve.

FIG. 3 is an enlarged sectional view of a reed valve plate.

FIG. 4 is a sectional view of the reed valve in an open state.

FIG. 5 is a partially cutaway perspective view showing a second embodiment of the reed valve plate.

FIG. 6 is a partially cutaway perspective view showing a third embodiment of a reed valve plate.

FIG. 7 is a partially cutaway perspective view showing a fourth embodiment of the reed valve plate.

FIG. 8 is a partially cutaway perspective view showing a fifth embodiment of the reed valve plate.

FIG. 9 is a partially cutaway perspective view showing a sixth embodiment of the reed valve plate.

FIG. 10 is a partially cutaway perspective view showing a seventh embodiment of the reed valve plate.

FIG. 11 is a partially cutaway perspective view showing an eighth embodiment of the reed valve plate.

[Explanation of symbols]

 Reference Signs List 5 reed valve 6 reed valve body 10 reed valve plate 11 distal end portion 12 proximal end portion 13 groove provided near proximal end portion

Claims (5)

[Claims] A reed valve body having a valve port; and a reed valve plate having a base end fixed to the reed valve body in a state of covering the valve port. An engine wherein the reed valve plate is configured to open and close a valve port in accordance with the operation of the above, wherein the reed valve plate is formed of a material mainly composed of polyetheretherketone resin. Reed valve device. 2. The reed valve plate has a low rigidity on the distal end side, the rigidity gradually increases from the distal end to the intermediate portion, a high rigidity in the intermediate portion and a portion closer to the proximal end than this, and a vicinity of the proximal end. 2. The reed valve device according to claim 1, wherein the reed valve device is formed so as to have lower rigidity than an intermediate portion. 3. The reed valve plate has a small thickness at the distal end side and a gradually increasing thickness from the distal end to the intermediate portion, and the intermediate portion and a portion closer to the proximal end thereof become thicker. The reed valve device according to claim 2, further comprising a low-rigidity portion having a shape with reduced rigidity in the vicinity. 4. The reed valve device according to claim 3, wherein a low-rigidity portion is provided near the base end of the reed valve plate by providing a groove extending in the width direction of the reed valve plate. 5. The reed valve device according to claim 1, which is applied to a small engine of a model helicopter or a model airplane.