JPH0530663U - solenoid valve - Google Patents

Abstract

(57) [Summary] [Purpose] To facilitate the formation of a passage that communicates with the return port of a solenoid valve. [Structure] The lower end of the spool valve 2 faces a spring chamber 15 and is biased upward by a coil spring 3. Plunger 5
2 is attracted downward by energizing the electromagnetic coil 4, and moves the spool valve downward via the shaft 51. A return port 12 is opened in the spring chamber 15, and a flow passage 16 that connects the spring chamber 15 and the line port 11 is formed in a recess on the outer periphery of the valve housing 2. The flow path 16 is opened by the upward movement of the spool valve 2, and the fluid in the line port 11 returns to the tank from the return port 12 via the spring chamber 15. The return port 12 also serves as a drain port that uses the spring chamber 15 as a tank pressure, and can easily form a passage that connects the return port and the drain port, which are separate from each other.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a solenoid valve, and more particularly to a structural improvement of a linear solenoid valve provided with a spool valve driven by an electromagnetic coil.

[0002]

[Prior Art]

 Linear solenoid valves are used for applications such as line pressure control of automatic transmissions (A / T). An example is shown in Fig. 3. In the figure, a spool valve 2 is slidable up and down in a small-diameter lower half valve housing 1A made of a non-magnetic material, and a line is provided at different positions in the longitudinal direction on the valve housing wall. A port 11, a return port 12, a supply port 13, and drain ports 14 and 19 are provided. The inner space of the valve housing facing the lower end of the spool valve 2 serves as a spring chamber 15, and the coil spring 3 provided in the spring chamber 15 biases the spool valve 2 upward.

A non-magnetic shaft 51 is disposed in the center of a large-diameter upper half valve housing 1 B made of a magnetic material, and the shaft 51 is supported by a bearing 54 so as to be vertically movable. A magnetic plunger 52 is fixed to the upper end of the shaft 51, and an electromagnetic coil 53 wound around a bobbin is provided around the shaft 51.

The drain ports 14 and 19 are respectively opened to the bearing chamber 55 and the spring chamber 15 which communicate with the bearing arrangement portion, and the pipelines to the tank (not shown) outside the solenoid valve are connected to these drain ports 14 and 19, respectively. The chambers 15 and 55 are maintained at tank pressure. The line port 11 is selectively connected to the supply port 13 that communicates with the pipeline for supplying the pressure fluid and the return port 12 that communicates with the pipeline to the tank by the lands 21 and 22 provided above and below the spool valve 2. Be punished.

When the electromagnetic coil 4 is energized, the plunger 52 and the shaft 51 move downward in accordance with the amount of energization, and the spool valve 2 moves downward against the spring biasing force. As the spool valve 2 moves downward, the communication area between the line port 11 and the return port 12 is gradually reduced by the land 22 and completely shut off. Then, the land 21 subsequently causes the line port 11 and the supply port 13 to be closed. The communication area gradually increases as they are connected. Thus, by moving the spool valve 2 to an appropriate position, the pressure fluid is supplied to the line port 11 (broken line in the figure) or returned from the line port 11 to the tank (solid line in the figure), and the line port 11 The fluid pressure is maintained at a predetermined control pressure.

The land 22 has a larger diameter than the land 21, and the feedback force is generated by the difference in the area of the end faces of the two land 21, 22 which receives the control pressure. The overall length is shortened for miniaturization.

[0007]

[Problems to be solved by the device]

 The solenoid valve has a large number of ports, especially three ports connected to the tank are open, and it is necessary to provide a passage connecting these ports to the equipment to which the solenoid valve is attached. It took time to form.

[0008]

[Means for Solving the Problems]

 To explain the structure of the present invention, a valve housing includes a line port 11 for outputting a controlled pressure fluid, a return port 12 for returning the fluid in the line port 11 to a tank, and a supply port 13 for supplying the pressure fluid to the line port 11. One end is pressed and urged by a spring member 3 formed in one wall and arranged in the chamber 15, and is linearly driven against the urging force of the spring member 3 by receiving the electromagnetic force of the electromagnetic coil 4. A spool valve 2 is provided in the valve housing 1, the return port 12 is opened to a spring chamber 15, and a flow passage 16 connecting the spring chamber 15 and the line port 11 is recessed in the outer peripheral portion of the valve housing 1. It was done.

[0009]

[Action]

 In the above structure, when the spool valve 2 moves in accordance with the amount of electricity supplied to the electromagnetic coil 4 and the land 21 opens the flow path 16, the line port 11 returns via the flow path 16 through the spring chamber 15. It is connected to the port 12. Further, when the flow path 16 is closed by the land 21, the line port 11 is connected to the supply port 13. In this way, the pressure of the line port 11 is set to the predetermined control pressure.

Further, in the present invention, the return port 12 communicating with the line port 11 is provided in the spring chamber 15 through the flow passage 16 recessed in the outer peripheral portion of the valve housing 1, and the spring chamber 15 is maintained at the tank pressure. It also has the function of a conventional drain port.

[0011]

【Example】

 In FIG. 1, the valve housing 1 of the solenoid valve is composed of a small-diameter lower half portion 1A and a large-diameter upper half portion 1B. A spool valve 2 is provided in the inside thereof so as to be vertically movable, and a lower end of the spool valve 2 is biased upward by a coil spring 3 provided in a spring chamber 15. Inside the valve housing 1B in the upper half, a shaft 51, a plunger 52, and an electromagnetic coil 53, which have the same basic structure as the conventional structure, are provided. When the electromagnetic coil 53 is not energized, a spool valve such as the right half in the figure is provided. 2 is at the upper end position due to the spring biasing force. When the electromagnetic coil 53 is energized, the plunger 52 is attracted downward, is pressed by the shaft 51, and the spool valve 2 moves downward against the spring biasing force (left half of the figure).

The spool valve 2 has large diameter lands 21 and 22 at upper and lower portions, and the upper land 22 has a drain port 14 and a line port 11 provided on the side wall of the lower half valve housing 1A. The land 21 on the lower side is opened and closed between the supply port 13 and the line port 11 at the upper end surface thereof.

A flow that flows through the annular groove 17 of the spool valve 2 to the line port 11 and is recessed in the side wall of the valve housing 1 A on the opposite side to extend downward with the fitting surface of the housing as a part of the side surface. A passage 16 (FIG. 2) is formed, which leads to the lower annular groove 18. The land 21 opens and closes between the annular groove 18 and the spring chamber 15 by its lower end surface. A return port 12 communicating with the tank outside the solenoid valve is opened through the side wall of the spring chamber 15. The land 22 has a diameter larger than that of the land 21, and a feedback force for urging the spool valve 2 upward is generated due to the area difference between the end surfaces of the lands 21 and 22 which receive the control pressure. Further, the housing 6 is formed with passages 11a, 12a, 13a and 14a corresponding to the respective ports.

When the electromagnetic coil 53 is not energized, the spool valve 2 is at the upper end position as shown in the right half of the figure by the spring biasing force, and the upper end surface of the land 21 separates the line port 11 and the supply port 13 from each other. On the other hand, the lower end surface opens the gap between the annular groove 18 and the spring chamber 15. As a result, as shown by the solid line in the figure, the fluid in the line port 11 reaches the spring chamber 15 via the flow path 16 and is returned to the tank via the return port 12 and the passage 12a.

When the electromagnetic coil 53 is energized, the plunger 52 is attracted downward by the electromagnetic force, and the spool valve 2 moves downward against the spring biasing force (left half of the figure). The spool valve 2 moves downward in accordance with the amount of electricity supplied to the electromagnetic coil 53, and the communication area between the flow path 16 and the spring chamber 15 gradually decreases with this movement. As shown by the broken line in the figure, the supply port 13 is made to communicate with the line port, and the communication area increases as the spool valve 2 moves downward. Thus, the fluid pressure of the line port 11 is controlled to a desired value by adjusting the amount of electricity supplied to the electromagnetic coil 53.

Thus, the return port 12 opening to the spring chamber 15 serves as a flow path for returning the fluid of the line port 11 to the tank, and also serves to maintain the internal pressure of the spring chamber 15 communicating with the tank at the tank pressure at all times. do.

[0017]

[Effect of the device]

 As described above, according to the solenoid valve of the present invention, the flow path connecting the line port and the return port of the spring chamber is provided in the outer periphery of the valve housing, and the port for returning the fluid of the line port to the tank and the spring It is possible to easily form a flow path that connects the ports for maintaining the internal pressure of the chamber at the tank pressure.

[Brief description of drawings]

FIG. 1 is an overall sectional view of a solenoid valve showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is an overall sectional view of a solenoid valve showing a conventional example.

[Explanation of symbols]

 1 Valve Housing 11 Line Port 12 Return Port 13 Supply Port 15 Spring Chamber 16 Flow Path 2 Spool Valve 21 Land 3 Coil Spring (Spring Member) 4 Electromagnetic Coil

Claims (1)

[Scope of utility model registration request] 1. A line port for outputting a controlled pressure fluid,
A return port that returns the fluid from the line port to the tank,
A supply port for supplying pressure fluid to the line port is formed on the valve housing wall, and one end is pressed and urged by a spring member arranged in the spring chamber and the urging force of the spring member is received by the electromagnetic force of the electromagnetic coil. A spool valve that is linearly driven against the valve housing is provided in the valve housing, the return port is opened to the spring chamber, and a flow path connecting the spring chamber and the line port is recessed in the outer peripheral portion of the valve housing. Solenoid valve characterized by having done.