JPH08226556A - Fiber reinforced resin lead valve - Google Patents

Abstract

PURPOSE: To improve durability to heighten flexural rigidity of a lead valve in the specific direction by laminating woven fabric and a fiber bundle in a laminating state to control anisotropy of the flexural rigidity of the lead valve as deired. CONSTITUTION: UD materials 2, 3 are made in a state to incline to the right against base lines L1 , L2 by 10 degrees to maximize a laminating state to control anisotropy of flexural rigidity of a lead valve 11 consisting of a fiber body laminating cloth materials 1, 4 which are woven cloth made of reinforced fiber and the UD materials 2, 3 which are fiber bundles and base material resin, that is, rigidity in the M1 , M2 directions. Consequently, even in the case when intake air flows in diagonally against the lead valve 11 and makes contact with it, it is possible to restrain lift of the lead valve 11 on one side end part, improve durability and extend longevity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber-reinforced resin reed valve, and more particularly to a reed valve for a two-cycle engine used in motorcycles and outboard motors, in which the flexural rigidity of the reed valve is anisotropic. Controlled as desired (eg,
The present invention relates to a fiber-reinforced resin reed valve in which the bending rigidity in a specific direction is higher than in the past.

[0002]

2. Description of the Related Art Reed valves for two-stroke engines are
It is provided to prevent the air-fuel mixture in the crankcase from being blown back during the piston lowering process, as in the case of the crankcase compression type two-cycle engine. Conventionally, a reed valve for a two-cycle engine has been formed of a stainless steel thin plate, but in recent years, due to a demand for higher performance of a two-cycle engine, a fiber which is lighter and has higher rigidity than a stainless steel thin plate. Reinforced resin reed valves are often used.

Many proposals have been made for fiber-reinforced resin reed valves. As literatures, for example, JP-A-3-227207 (method for manufacturing reed valve valve body),
Japanese Patent Laid-Open No. 61-109977 (fiber-reinforced resin reed valve), Japanese Patent Publication No. 61-31340 (reed valve reed), Shokai 61-16470 (reed valve valve), and Shokai 61-67468 (two-cycle engine). Reed valves) in the above.

[0004]

A fiber-reinforced resin reed valve in which a base material resin is reinforced with a reinforcing fiber such as glass fiber or carbon fiber is lightweight and has high rigidity as described above.
Although it has excellent responsiveness, it also has the property of being relatively fragile. Hereinafter, problems of the prior art will be described with reference to FIGS.

In a two-cycle engine, the intake pipe may be arranged obliquely with respect to the reed valve depending on the engine layout of a motorcycle or an outboard motor. FIG. 5 shows an example of the layout of a motorcycle two-cycle engine. Since the suspension component 2 is located behind the cylinder 1 (engine) (on the right side in the figure), the carburetor 3
The intake air that flows into the cylinder 1 through the exhaust gas flows into the cylinder 1 obliquely from the rear (lower right side in the drawing).

FIG. 6 is a side view of a two-stroke engine of the type shown in FIG. Intake and exhaust are performed through an intake pipe 4 and an exhaust pipe 5 that are connected to the cylinder 1 as indicated by a single arrow in the figure. A reed valve 7 is mounted on the reed valve mounting portion 6 at the tip of the intake pipe 4, and when the engine is driven, it moves as shown by a double-headed arrow in the figure. FIG. 7 is an explanatory view when FIG. 6 is viewed from the direction A, and intake air flows into and comes into contact with the reed valve 5 from an oblique direction.

FIG. 8 is an explanatory view of FIG. 6 viewed from the direction B, and shows a state where the end portion of the reed valve 7 is slightly lifted (turned up). As shown in FIG. 7, intake air that flows into and contacts the reed valve 7 obliquely flows into and contacts the reed valve 7, so that the left side of the reed valve 7 lifts more in FIG. 9 shows the reed valve 7
It is explanatory drawing of the attachment state of. Two reed valves 7
Are mounted so as to sandwich the valve seat 8, and the movement of the reed valve 7 on the side opposite to the valve seat 8 is restricted by a stopper 9 (fixed with a screw 10).

FIG. 10 is an explanatory view of a deformed state of the reed valve 7 in FIG. 8, and FIG. 10 (a) shows the reed valve 5.
10B is a view of FIG. 10A viewed from the direction C, and shows the lifted state of the reed valve 7 (the state of the end portion that is turned up). Since the lifted state of the reed valve 7 is biased, the portion shown by the diagonal lines in FIG. 10A has a larger lift amount (higher surface pressure) than the other portions, and therefore, the impact received by this portion is also high. Because it is large, it is easily damaged in an early stage.

The above problems are also caused by the conventional method for manufacturing a fiber-reinforced resin reed valve. Based on FIG.
An example of a conventional method for manufacturing a fiber-reinforced resin reed valve will be described. The reed valve 7 is made of cloth material (for example, carbon fiber hardened with epoxy resin; woven cloth is schematically shown here), UD material [unidirectional material (or fiber bundle); Same as cloth material], UD material (same as) and cloth material (same as) are sequentially laminated, heated and pressed to form a plate-like member, and punched into a desired shape.

In this case, the rigidity of the left and right pieces of the reed valve 7 in FIG. 11 is determined by the center lines L ₁ and L ₂ of the left and right pieces (these directions are the same as the direction of the fiber bundle of the UD material in FIG. 11). the same)
It becomes symmetric with respect to, and therefore breakage in the shaded portion of FIG. 10 (a) is unavoidable.

The present invention has been made to solve the above-mentioned problems of the prior art. The object of the present invention is to control the anisotropy of bending rigidity of a reed valve as desired, and as a result, It is an object of the present invention to provide a fiber-reinforced resin reed valve in which bending rigidity in a specific direction of the valve is higher than in the past.

[0012]

That is, the fiber-reinforced resin reed valve of the present invention is a woven fabric and /
Alternatively, in a fiber-reinforced resin reed valve comprising a fibrous body in which fiber bundles are laminated and a base material resin, the woven fabric and / or the woven fabric and / or the laminated fabric in which the anisotropy of bending rigidity of the reed valve can be desirably controlled. It is characterized in that fiber bundles are laminated.

The reinforcing fibers that can be used in the fiber-reinforced resin reed valve of the present invention include those conventionally used as reinforcing fibers, such as glass fiber, alumina fiber, silica fiber,
Examples thereof include carbon fiber, boron fiber, polyaramid fiber and the like. These fibers can be used alone or in combination. Further, the base material resin also includes those commonly used for the same purpose, such as epoxy resin and unsaturated polyester resin. These base material resins may also be used alone or in combination. When the base resin is a thermosetting resin,
For example, it can be used in the form of being impregnated with fiber reinforcement, or when the matrix resin is a thermoplastic resin, it can be used as a fiber form in advance by mixing or knitting with reinforcing fibers.

The woven fabric made of reinforcing fibers may be woven by a conventional weaving method such as a twill weave and a plain weave. Further, the fiber bundle made of reinforcing fibers may be a bundle of predetermined reinforcing fibers. When forming the fibrous body, the woven fabric and the fiber bundle may be of the same type or different types, and may be appropriately laminated.

The laminated form capable of controlling the flexural rigidity anisotropy of the reed valve as desired means, for example, when the fibrous body is formed, (a) the angle formed by the woven fabric made of reinforcing fibers and / or the fiber bundle. Are appropriately varied so as to obtain desired product characteristics (for example, to increase rigidity in a specific direction), (b) specific portion (or specific direction) of woven fabric and / or fiber bundle composed of reinforcing fibers It is conceivable to make the material, amount, or number of (1) different from each other so as to obtain desired product characteristics (for example, to increase rigidity in a specific direction).
The method (a) is preferable because it can be easily carried out.

The fiber-reinforced resin reed valve having a desired shape is, for example, a woven cloth and / or a fiber bundle (for example, epoxy prepreg of glass fiber or carbon fiber, a mixed woven cloth of glass fiber, carbon fiber and thermoplastic resin fiber, etc.). After laminating, the flat plate molded by heating and compression can be punched into a desired shape to be manufactured.

[0017]

When the laminated form of the reed valve is changed as in the present invention and the woven fabric and / or the fiber bundle is laminated, the anisotropy of the bending rigidity (that is, the pattern of the bending rigidity change due to the angle deviation from the reference line). Can be suitably controlled according to the purpose.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings. In the figure, the same or corresponding parts as those of the conventional example are designated by the same reference numerals, and detailed description thereof is omitted.

Example 1 As shown in FIG. 1, the fiber-reinforced resin reed valve 11 of Example 1 is similar to the conventional reed valve 7 of FIG.
Cloth material (for example, carbon fiber hardened with epoxy resin; woven cloth is schematically shown here), UD material [unidirectional material (or fiber bundle); material is the same as cloth material] , UD material (the same as) and cloth material (the same as) are sequentially laminated, and heated and pressed to form a plate-like member,
It can be manufactured by punching this into a desired shape. However, when the reed valve 11 of Example 1 is manufactured, compared to the case of manufacturing the conventional reed valve 7 with respect to the UD material of ,, 10 ° to the right in the figure.
Tilt and stack. Therefore, the product reed valve 11
, The angle θ between M ₁ (this direction is the same as the direction of the fiber bundle of the UD material in FIG. 1) and L ₁ , or M
_The angle θ formed by ₂ (this direction is the same as the direction of the fiber bundle of the UD material in FIG. 1) and L ₂ is 10 °.

FIG. 2 shows the distance from the reference line (L ₁ , L ₂ ) of the reed valve 11 of the first embodiment (in the figure, the clockwise rotation angle is positive and the counterclockwise rotation angle is negative). FIG. 7 is a diagram showing a change in bending rigidity (rigidity when bent in a direction orthogonal to each direction) due to (). For reed valve 11, 1
It can be seen that the bending rigidity is maximum at 0 ° (M ₁ , M ₂ ), and therefore the bending rigidity of the reed valve 11 is asymmetrical.

A durability test of the reed valve will be described with reference to FIG. FIG. 3A shows a simple reed valve durability tester. Holes 14 (total of 8 holes) are formed in a disk 13 supported by a rotary shaft 12 (for example, rotatable in a direction of a rotary arrow). Pipes 15, 16 while rotating the disk 13
By injecting air (air pressure 6 kg / cm ² ) into the hole 14 through the through hole, air can be intermittently blown onto the test object. Base plate 17 in front of pipe 16
The reed valve 11 was attached to the (made of rubber-baked aluminum) with the stopper 18 made of metal. FIG. 3B shows a front view of the disk 13. Further, FIG. 3C shows the right half of the reed valve 11, and a portion surrounded by a broken line is an air blowing portion 19 from the pipe 16.

Using the reed valve durability tester shown in FIG. 3, the time until the reed valve was broken was measured by intermittently supplying air at a frequency corresponding to 10000 rpm of the actual vehicle, and the reed valve 11 of Example 1 was measured. Showed 6 times the durability as compared with the conventional reed valve 7.

Embodiments 2 and 3 FIG. 4 shows Embodiment 2 [FIG. 4 (a)] and Embodiment 3 of the present invention.
It is a figure for demonstrating the manufacturing process of the fiber body of the fiber-reinforced resin reed valve of [FIG.4 (b)]. Example 2 is
The same as in Example 1 except that the cloth material of No., is rotated to the right (or left) by 45 °. In addition, Example 3 is a conventional example (see FIG. 1) except that the cloth material is rotated 10 ° to the right.
The same as 1). Even if these laminating methods are used, a reed valve having excellent durability can be obtained as in the first embodiment. The fiber-reinforced resin reed valve of the present invention is not limited to the laminated form of the fibrous body,
The stacking form can be appropriately changed depending on the material used, the angle of intake, and the like.

[0024]

Since the fiber-reinforced resin reed valve of the present invention has the above-described structure, even if the intake direction is oblique to the reed valve, the extreme valve lift at one end is achieved. Is suppressed, the durability is improved, and therefore the life of the reed valve can be extended.

When manufacturing the fiber-reinforced resin reed valve of the present invention, for example, even if there are several motorcycle models having different angles in the intake direction, the mold and the like are not changed,
It is possible to manufacture even by changing only the laminated pattern, and since many dies can be used for punching,
The manufacturing process is not complicated, the productivity is good, and the manufacturing cost is not increased.

[Brief description of drawings]

FIG. 1 is a diagram for explaining a manufacturing process of a fiber-reinforced resin reed valve according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a change in bending rigidity due to an angle deviation from a reference line of the reed valve of Example 1.

FIG. 3 is an explanatory diagram of a durability test of a reed valve.

FIG. 4 is a drawing for explaining the manufacturing process of the fiber body of the fiber-reinforced resin reed valve of Example 2 and Example 3 of the present invention.

FIG. 5 is an explanatory diagram of an example of a layout of a two-cycle engine for a motorcycle.

FIG. 6 is an explanatory view of the two-cycle engine viewed from the side.

FIG. 7 is an explanatory view of FIG. 6 viewed from the direction A.

FIG. 8 is an explanatory diagram of FIG. 6 viewed from a B direction.

FIG. 9 is an explanatory diagram of a mounted state of the reed valve.

10 is an explanatory diagram of a deformed state of the reed valve in FIG.

FIG. 11 is a diagram for explaining a manufacturing process of an example of a conventional fiber-reinforced resin reed valve.

[Explanation of symbols]

1: Cylinder 2: Suspension parts 3: Carburetor 4: Intake pipe 5: Exhaust pipe 6: Reed valve mounting part 7, 11: Reed valve 8: Valve seat 9, 18: Stopper 10: Screw 12: Rotating shaft 13: Disk 14 : Hole 15, 16:
Piping 17: Base plate 19: Air spraying point

Claims (1)

[Claims] 1. In a fiber-reinforced resin reed valve made of a base material resin and a fibrous body in which a woven fabric and / or fiber bundles made of reinforcing fibers are laminated, a flexural rigidity anisotropy of the reed valve is desired. The woven fabric and / or in a controllable laminated form
Alternatively, a fiber-reinforced resin reed valve is characterized in that fiber bundles are laminated.