JPH0637530U - Intake valve device - Google Patents

Abstract

(57) [Abstract] [Purpose] The purpose of the present invention is to improve the intake efficiency of fuel gas by improving the shape and configuration of the intake valve in order to eliminate the drawbacks of the conventional reed valve devices. is there. In an intake valve device using crank chamber pressure of a two-cycle engine, an intake valve 1 is formed in a semi-conical shape or a semi-elliptic cone shape, and a spring portion or a spring member 3 is provided at a fixed end side of a root.
It is characterized by the provision of.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an intake valve device that utilizes the crank chamber pressure of a two-cycle engine.

[0002]

[Prior art]

 Until now, the intake valve device utilizing the crank chamber pressure of the two-cycle engine has been a so-called reed valve device made of an elastic flat plate. This reed valve is provided with a window frame that supports the reed at the outlet of the intake passage of the reed valve body.One end of the reed consisting of a flat plate is fixed to this window frame of an inclined flat surface and the other end is elastic. It opens and closes in contact with it, and is sealed by the valve seat on the window frame. In order to regulate the opening of the reed, a curved stopper is provided above the reed and fixed to the reed valve body together with the reed. When the two reed valves are opposed to each other, a valve body having a substantially V-shaped cap body is formed and a window frame is provided at the center of the outlet of the fuel gas passage. Therefore, when the fuel gas passes through the reed valve body, the window frame at the outlet of the passage obstructs the flow of the fuel gas, and a sufficient opening at high speed cannot be obtained. Especially when the two reeds are opposed to each other, the flow of fuel gas collides with the center of the inside of the outlet of the reed valve body and is disturbed. Further, since the lead inclination angle is steep, the lead opening / closing resistance is large, the crank chamber pressure cannot be sensed sensitively, and the low-speed followability deteriorates. Further, when the fuel gas passes through the intake valve, the reed valve is a flat plate, so it hits the surface and scatters in the lateral direction of the valve. Due to these factors, improvement of inhalation efficiency is hindered.

[0003]

[Problems to be solved by the device]

 The present invention has been made in view of the above points and has an object to improve the shape and configuration of an intake valve to improve the intake efficiency of fuel gas.

[0004]

In order to achieve the above object, in an intake valve device that utilizes the crank chamber pressure of a two-cycle engine, the intake valve 1 is formed in a semi-conical shape or a semi-elliptical cone shape, and the root is fixed. A spring portion or a spring member 3 is provided on the end side.

[0005]

[Action]

 With this configuration, the fuel gas that pushes open the intake valve 1 and flows into the crank chamber flows to the free end side along the inner surface of the intake valve 1 formed in a semi-conical shape. At this time, by increasing the length of the semi-conical portion of the intake valve 1, the inclination angle of the intake valve 1 can be made small, so that the crank chamber pressure can be sensed more sensitively, and especially the low-speed followability is improved. Further, since the inclination angle is small, the deformation ratio of the intake valve 1 with respect to the change in the valve opening is small, so that the stopper 4 required in the conventional reed valve is not necessary. On the other hand, at high speed, since the valve body 3 does not have the window frame, the suction resistance can be reduced. In particular, when two reed valves are opposed to each other, the valve body need not have a valve seat by providing the seal width portion 6 that matches the valve that opposes the end edge portion of the intake valve 1, and the passage can be made extremely wide. This also makes it possible to produce a gas rectifying action. However, the flow of the fuel gas flows along the inner surface of the intake valve 1 so that the fuel gas is converged without leaking laterally and is guided vigorously into the crank chamber. Therefore, the intake efficiency is increased and the engine output is improved.

[0006]

【Example】

 An embodiment of the present invention will be described below. FIG. 1 (a) is a side view of the lower half of the present invention in section, and FIG. 1 (b) is a front view of the present invention. In FIGS. 1A and 1B, intake valves 1 are provided above and below a valve body 2. The intake valve 1 is formed in a semi-conical shape, and a spring portion 3 is provided on the fixed end side of the root. Then, each intake valve 1 is provided with a seal width portion 8 matching the opposing valve at the end edge portion thereof, which is coated with a thin curtain of elastic material. The shape of the valve body 2 is a truncated cone, and it fits inside the intake valve 1 so that it enters inside, and the surface of the intake valve 1 that is in elastic contact is coated with rubber. Further, the inner passage of the valve body 2 has a circular orifice shape that promotes smooth flow of fuel gas. Each intake valve 1 is attached to the valve body 2 with the spring portion 3 by the fixing screw 5 with the seal width portion 8 matching the opposing valve facing the edge portion. FIG. 2 is a central longitudinal sectional view of the present invention in operation, showing the intake valve 1 in a fully opened state. At this time, the intake valve 1 is opened to be approximately the same size as the inner passage of the valve body 2 and has a circular arc around it, so that it is like an extension of a pipe and promotes a smooth flow of fuel gas. To do. Since the lower end of the intake valve 1 moves forward when the intake valve 1 is open, the valve body 2 is set long to prevent fuel gas from leaking to both sides. FIG. 3 is a view of the valve body 2 of the present invention viewed from the upstream inlet side of the fuel gas, and FIG. 4 is a top view of the fuel gas flowing into the valve body 2 in the conventional reed valve device shown in FIG. It is a figure I seen from the mouth side. Comparing the two, the difference between the fuel gas passage resistance and the opening area can be seen clearly. In this embodiment, nothing is interposed between the opposed intake valves, but it is conceivable to provide one thin plate to enhance the effect of the valve sheet. Further, in order to make the opening area larger or to widen the spring portion, the intake valve 1 is formed from a semi-conical shape to a semi-elliptical cone shape, or a spring member separate from the intake valve 1 is provided in the spring portion. It is also possible.

[0007]

[Effect of device]

 (A) Since there is no obstacle inside the valve body, the disturbance of intake air is eliminated, and the opening area of the outlet can be widened, the intake efficiency is increased. (B) The valve body consists of a circular passage, and the force of the fuel gas is increased due to the orifice effect, and the fuel gas is focused even after passing through the valve body, so the suction efficiency is increased. (C) Since the angle of inclination at the base of the intake valve can be made small, the crank chamber pressure can be sensed more sensitively, and especially the low-speed followability is improved. The results shown above have the effect of improving the engine output. Therefore, fuel efficiency is also improved.

[Brief description of drawings]

FIG. 1 (a) is a side view of a lower half of the present invention in section.

FIG. 1 (b) is a front view of the present invention.

FIG. 2 is a central longitudinal sectional view of the present invention in operation.

FIG. 3 is a view I of the valve body 2 of the present invention viewed from the upstream inlet side of fuel gas.

FIG. 4 is a view I of the valve body 2 of the conventional reed valve device as seen from the upstream inlet side of the fuel gas.

FIG. 5 is a side view in which a part of a conventional reed valve device is cut away.

[Explanation of symbols]

 1 intake valve 2 valve body 3 spring part 4 stopper 5 fixing screw 6 seal width part

Claims (1)

[Scope of utility model registration request] 1. An intake valve device utilizing the crank chamber pressure of a two-cycle engine, wherein an intake valve 1 is formed in a semi-conical shape or a semi-elliptical cone shape, and a spring portion or a spring member 3 is provided on the fixed end side of the root. An intake valve device characterized by the above.