JPH0632857U - Pressure control valve - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the pressure control characteristics of the pressure regulating valve. [Structure] The receive plate 4 is located above the diaphragm 3.
Is fixed, and the valve body 6 is fixed on the lower side. The receive plate 4 is provided with a recess for positioning the compression coil spring 5, and the compression coil spring 5 is positioned and sandwiched between the upper cover 1 and the receive plate 4. The elastic force of the compression coil spring 5 is the valve body. Acts as if pressing 6 downwards. The central axis of the compression coil spring 5 is decentered from the diaphragm center position by a predetermined distance, and the compression coil spring receiving surface of the receive plate 4 is inclined by a predetermined angle. When a load is applied to the compression coil spring 5 while the pressure regulating valve is in use, the facing surfaces of the valve body 6 and the valve seat 8 are parallel to each other.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pressure control valve, and more particularly to a pressure control valve suitable for fuel pressure control of a fuel injection device.

[0002]

[Prior art]

 In a fuel injection device of an automobile engine, fuel pressurized by a fuel pump is injected from an injection nozzle into an intake pipe through a solenoid valve. The fuel supply amount can be controlled by controlling the opening time of the solenoid valve, but it is necessary to keep the fuel pressure at the solenoid valve inlet constant.

Conventionally, a diaphragm type pressure regulating valve has been used as a pressure regulating valve for controlling such fuel pressure. In the diaphragm pressure control valve, the valve element held by the diaphragm is urged toward the valve seat by the compression coil spring, and the fluid pressure acts on the diaphragm to resist the elastic force of the compression coil spring. Is separated from the valve seat, and the fluid is caused to flow out between the valve body and the valve seat to control the pressure of the fluid to be constant.

In such a diaphragm type pressure adjusting valve, since the valve element is held by the diaphragm, it is easy to incline, and when the valve element inclines, the valve element comes in contact with the valve seat and the pressure adjusting characteristic deteriorates. .

In a pressure regulating valve proposed in Japanese Patent Publication No. Sho 49-37049 to solve the problem, a substrate held by a diaphragm rotatably supports a ball fixed to a valve body. . Even if the base plate tilts with respect to the valve seat, the valve body rotates with respect to the base plate and the valve body is kept parallel to the valve seat.

[0006]

[Problems to be solved by the device]

 The pressure control valve proposed in Japanese Patent Publication No. 49-37049 has a drawback that it has a large number of parts and a large number of assembly steps.

The present invention has been made to solve the above problems, and an object thereof is to provide a pressure adjusting valve having a simple structure, a small number of parts and a small number of assembling steps, and good pressure adjusting characteristics.

[0008]

[Means for Solving the Problems]

 The pressure regulating valve of the present invention is a pressure regulating valve in which a valve element held by a diaphragm is urged toward a valve seat by a compression coil spring, and the compression coil spring of a receiving plate fixed to the diaphragm and receiving the compression coil spring. The positioning center is displaced from the center of the diaphragm in the specified direction by a specified distance with respect to the tip of the compression coil spring end turn.

Further, in a pressure adjusting valve in which a valve element held by a diaphragm is biased toward a valve seat by a compression coil spring, a compression coil spring receiving surface of a reception plate fixed to the diaphragm and receiving the compression coil spring. Is tilted by a predetermined angle with respect to the valve seat.

Further, in a pressure regulating valve in which a valve element held by a diaphragm is urged toward a valve seat by a compression coil spring, a compression coil spring positioning center of a reception plate fixed to the diaphragm and receiving the compression coil spring is a diaphragm. The coil coil spring is displaced from the center by a predetermined distance in the predetermined direction with respect to the tip end of the compression coil spring, and the compression coil spring receiving surface is inclined by a predetermined angle with respect to the valve seat.

[0011]

[Action]

 When a compression coil spring is sandwiched between two parallel plates and compressed, the line of action of the combined load is generally eccentric from the center axis of the spring. As shown in Fig. 5, when the center of the receive plate and the central axis of the compression coil spring positioned by the cover are aligned and the receive plate is supported at the center of the diaphragm, the action line of the pressure of the fluid acting on the diaphragm, that is, the load application point. Is the center of the receive plate, but the line of action of the load applied to the compression coil spring is eccentric.

That is, the action line of the reaction force of the compression coil spring and the action line of the fluid pressure do not coincide with each other, and a bending moment is generated. As shown in the figure, the receive plate is eccentric by a distance E, and Incline. Since the seat surface of the valve seat is parallel to the cover, the valve body integrated with the receive plate hits the valve seat on one side and the pressure control characteristics deteriorate.

In the pressure regulating valve of the present invention, the positioning center of the compression coil spring of the receiving plate is previously displaced from the center of the diaphragm in the predetermined direction with respect to the tip end of the compression coil spring end winding, and the compression coil spring receiving surface is moved to the valve seat. By tilting the valve body by a predetermined angle, the position of the valve body after applying the load can be made parallel to the seat surface, and good pressure control characteristics can be obtained.

As described above, the position of the valve body can be made parallel to the seat surface by eccentricizing the compression coil spring positioning center of the receiving plate and inclining the compression coil spring receiving surface, but Even if the center of the compression coil spring is eccentric, or the inclination of the compression coil spring receiving surface is set, the eccentric amount or inclination angle can be set to a predetermined value to make the valve body parallel to the seat surface. Becomes

Further, since the valve body is not rotatably supported, it does not vibrate due to the flow of fluid and the fluid pressure does not fluctuate periodically.

[0016]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a pressure regulating valve which is an embodiment of the present invention. As shown in the figure, an upper cover 1 and a lower cover 2 formed of a thin plate are integrally crimped so as to sandwich the diaphragm 3.

A receive plate 4 is fixed on the upper side of the diaphragm 3, and a valve body 6 is fixed on the lower side. The receive plate 4 is provided with a recess for positioning the compression coil spring 5, and the compression coil spring 5 is positioned and sandwiched between the upper cover 1 and the receive plate 4, and the elasticity of the compression coil spring 5 is It acts to push the valve body 6 downward.

An inflow pipe 9 and a boss 7 are fixed to the lower cover 2, and an outflow pipe 10 and a valve seat 8 are press-fitted into the boss 7. A ventilation pipe 11 is fixed to the upper cover 1. The ventilation pipe 11 communicates with the intake pipe of the engine, and the inflow pipe 9 communicates with the discharge side of the fuel pump, that is, the inlet side of the solenoid valve for ejecting fuel into the suction pipe. The outflow pipe 11 communicates with the fuel tank so as to return the fuel to the fuel tank.

In the above configuration, when the difference between the pressure of the intake pipe and the fuel pressure at the inlet of the solenoid valve becomes large, the pressure difference above and below the diaphragm becomes large, and the valve body 6 resists the elastic force of the compression coil spring 5. The fuel is pushed upward, the gap between the valve body 6 and the valve seat 8 is widened, the fuel is returned from the outflow pipe 10 to the fuel tank, and the pressure of the fuel is lowered.

When the pressure of the fuel is small, the elastic force of the compression coil spring 5 becomes larger than the pressure acting on the diaphragm 3, the valve body 6 is pressed against the valve seat 8 and the fuel passage is closed. In this way, the fuel pressure at the solenoid valve inlet is controlled to be constant.

In order to improve the pressure control characteristics, it is important that the opposed surfaces of the valve body 6 and the valve seat 8 are parallel to each other. Therefore, the central axis of the compression coil spring 5 is decentered from the diaphragm center position, The compression coil spring receiving surface of the receive plate 4 is inclined. In the embodiment, the amount of eccentricity and the tilt angle are experimentally obtained, and the results are shown in FIG.

As shown in the figure, the lower coil end of the compression coil spring is positioned on the protrusion provided on the receive plate, and the upper coil end, not shown, is positioned by the protrusion provided on the upper cover. There is.

As shown in the figure, when the coil center axis is the origin of the XY coordinates and the tip of the end turn is on the X axis, the XY coordinates of the diaphragm center are eccentric (0.129 mm, -0.164 mm), and are received. The upper surface of the plate was inclined 5 ° 05 'with respect to the lower surface. The specifications of the compression coil spring are shown in Table 1.

FIG. 3 shows a deformed state of the compression coil spring. As shown in the figure, when no load is applied to the compression coil spring, the lower surface of the receive plate is inclined and the diaphragm center is eccentric from the coil spring center axis determined by the upper cover, but when a set load is applied, the diaphragm center becomes the coil spring center. Consistent with the axis, the bottom surface of the receive plate is horizontal.

[0025]

The surface of the valve body facing the valve seat is parallel to the lower surface of the receive plate, and when the load is applied to the compression coil spring, the surface of the valve body facing the valve seat is parallel to the seat surface as shown in FIG. Even better pressure control characteristics were obtained.

In the embodiment, the compression coil spring positioning center of the receiving plate is eccentric and the compression coil spring receiving surface is inclined to make the position of the valve body parallel to the seat surface, but the compression coil spring positioning center of the receiving plate is arranged. It is also possible to make the valve body eccentric by a predetermined distance in a predetermined direction, or to incline the compression coil spring receiving surface by a predetermined angle to make the valve body parallel to the seat surface.

Furthermore, in the embodiment, the eccentricity amount and the tilt angle of the receive plate are obtained by experiments, but they may be obtained by calculation. In that case, as shown in FIG. 4, first, the load conditions and spring specifications are determined, and the eccentricity E and the tilt of the receive plate at the time of load application are determined by the finite element method or the like.

When the eccentricity amount E and the inclination of the receive plate calculated in this way become 0, the calculation is terminated, and when they are not 0, the eccentricity amount e and the inclination angle of the receive plate are set or updated and calculated. repeat. In this way, the eccentricity amount and tilt angle of the receive plate that makes the valve element fixed to the lower surface side of the receive plate parallel to the valve seat can be obtained.

[0030]

[Effect of device]

 As described above, according to the pressure regulating valve of the present invention, the valve body after load application can be made parallel to the sheet surface, and good pressure control characteristics can be obtained.

Further, since the valve body is not rotatably supported, it does not vibrate due to the flow of fluid and the fluid pressure does not fluctuate periodically. Furthermore, the structure is simple and the number of parts is small, so the manufacturing cost is low.

[Brief description of drawings]

FIG. 1 is a sectional view showing a pressure regulating valve according to an embodiment of the present invention.

FIG. 2 (a) is a front view showing details of a compression coil spring of the same pressure regulating valve, and FIG. 2 (b) is a bottom view thereof.

FIG. 3 is a front view showing a deformed state of a compression coil spring of the pressure control valve.

FIG. 4 is a flowchart for obtaining the eccentric amount of load acting point of the compression coil spring by calculation.

FIG. 5 is a diagram showing a deformed state when a load is applied to the central axis of a compression coil spring.

[Explanation of symbols]

 1 Upper cover 2 Lower cover 3 Diaphragm 4 Receive plate 5 Compression coil spring 6 Valve body 7 Boss 8 Valve seat 9 Inflow pipe 10 Outflow pipe 11 Vent pipe

Claims (3)

[Scope of utility model registration request] 1. A pressure regulating valve in which a valve element held by a diaphragm is urged toward a valve seat by a compression coil spring,
A pressure regulating valve characterized in that a compression coil spring positioning center of a receiving plate fixed to a diaphragm and receiving the compression coil spring is displaced from the center of the diaphragm by a predetermined distance in a predetermined direction with respect to the tip of the compression coil spring end turn. 2. A pressure regulating valve in which a valve element held by a diaphragm is urged toward a valve seat by a compression coil spring,
A pressure regulating valve characterized in that a compression coil spring receiving surface of a receiving plate fixed to a diaphragm and receiving the compression coil spring is inclined at a predetermined angle with respect to a valve seat. 3. A pressure regulating valve in which a valve element held by a diaphragm is urged toward a valve seat by a compression coil spring,
The positioning center of the compression coil spring of the receiving plate fixed to the diaphragm and receiving the compression coil spring is displaced from the center of the diaphragm by a predetermined distance in a predetermined direction with respect to the tip of the compression coil spring end winding, and the compression coil spring receiving surface is against the valve seat. A pressure regulating valve characterized by being tilted at a predetermined angle.