JP2002310331A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the property at starting operation without impairing the durability. SOLUTION: This solenoid valve 1 comprises a sub-valve 11 and a main valve 12. The main valve 12 is used to control a high pressure. The sub-valve 11 closes a first input port 25 of a nozzle portion 24 during no current flow in a solenoid 21 and opens a first drain port 27 of a core 26. During current flow, the first drain port 27 is closed and the first input port 25 is opened to output a pilot pressure to the main valve 12. A first coil spring 53 is provided between an end face 43 of a second plunger 41 of the main valve 12 and a wall face 44 of the nozzle portion 24 for energizing the second plunger 41 to be apart from the wall face 44. The energizing force of the first coil spring 53 and the energizing force of a second coil spring 63 are balanced with each other in the state of forming a gap 67 between the second plunger 41 and the wall face 44.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a solenoid valve for controlling, for example, an output pressure.

[0002]

2. Description of the Related Art Conventionally, an electromagnetic valve 101 as shown in FIG. 2 has been used in a pneumatic control circuit.

[0003] The solenoid valve 101 includes a sub-valve 112 that operates in accordance with energization of a solenoid 111, and a main valve 113 that operates by pilot pressure from the sub-valve 112. The sub-valve 112 includes a first plunger 114 driven by a solenoid 111, and the first plunger 114 is configured to open and close a first input port 115 to which pilot air pressure is input. I have. The pressure input to the first valve chamber 116 from the first input port 115 is
The supply chamber 1 of the main valve 113 through the communication passage 118 of
19 is supplied to the supply chamber 11.
9 is configured to be able to operate the large-diameter second plunger 121.

Accordingly, the first of the sub-valves 112
By operating the plunger 114 to operate the second plunger 121 of the main valve 113 and moving the valve body 122 at the tip of the second plunger 121, the second input port 123 is opened and the large capacity High pressure air second
The output port 124 is configured to be able to output.

[0005]

However, in such a solenoid valve 101, the end face of the second plunger 121 urged by the coil spring 131 comes into contact with the end face of the nozzle portion 117 when not operating. Is configured. For this reason, both 117,
Due to sticking of 121 and sticking of both 117 and 121 with an oily sticky substance during long-term operation, there is a concern that the operability of the second plunger 121 may be deteriorated when the solenoid valve is started.

In order to solve this, the counterbore 141 on the end face of the second plunger 121 is set to have a large diameter and the nozzle portion 1
Although it is conceivable to reduce the contact area with the 17 end face, the contact portion 142 forms a contact surface when the second plunger 121 returns, and it is necessary to secure a predetermined rigidity. I couldn't.

The present invention has been made in view of such conventional problems, and has as its object to provide an electromagnetic valve capable of improving the characteristics at the start of operation without impairing durability. It is.

[0008]

According to a first aspect of the present invention, there is provided an electromagnetic valve, comprising: a sub-valve for outputting a pilot pressure in accordance with energization of a solenoid;
A main valve having a plunger that operates in accordance with the pilot pressure from the sub-valve, for supplying the pilot pressure between the plunger and a wall surface facing the plunger end surface. In the solenoid valve in which the supply chamber is formed, when the plunger is located near the wall and is not operated, an urging member for urging the plunger to be separated from the wall is formed by the plunger and the wall. Between the two.

That is, an urging member is provided between the plunger and the wall surface facing the plunger, and the plunger positioned near the wall surface when not in operation is moved by the urging member. Is kept away from the Thus, a non-contact state between the plunger end surface and the wall surface during non-operation is ensured.

Further, in the solenoid valve according to the second aspect, there is provided an urging means for urging the plunger toward the wall surface.
The urging force is set so that the urging force of the urging means and the urging force of the urging member are balanced with a gap formed between the plunger and the wall surface during the non-operation.

That is, by providing the urging means for urging the plunger toward the wall surface side, the plunger can be moved toward the wall surface when not in operation. At this time, in a state where a gap is formed between the plunger and the wall surface, each urging force is adjusted so that the urging force of the urging means and the urging force of the urging member provided between the plunger wall surfaces are balanced. Is set. For this reason, a disadvantage caused by providing the urging means for urging the plunger toward the wall surface is prevented.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a solenoid valve 1 according to the present embodiment. The solenoid valve 1 controls, for example, a pressure in an air circuit.

The solenoid valve 1 includes a sub-valve 11 for controlling the flow of a small volume of air, and a main valve 12 which operates in accordance with the pilot pressure output from the sub-valve 11. It is configured to control the flow of a large volume of air to control the high pressure.

The sub-valve 11 has a solenoid 21, and a small-diameter first valve is provided inside the solenoid 21.
A plunger 22 is movably accommodated. The first
The plunger 22 is biased by a spring 23, and when the solenoid 21 is not energized, closes the first input port 25 formed in the nozzle portion 24 on the distal end side and is formed on the core 26 on the proximal end side. The first drain port 27 is opened (see A side in FIG. 1). Also, when the solenoid 21 is energized, the first plunger 22 is sucked toward the core 26 to close the first drain port 27 of the core 26 and to close the nozzle portion 24. The first input port 25 is configured to be open (see the B side in FIG. 1).

As a result, the first input port 25
The air pressure is input into the valve chamber 31, and the air pressure can be output to the main valve 12 from the communication passage 32 formed in the nozzle portion 24 as the pilot pressure.

The main valve 12 has a second plunger 41 which moves in a piston manner as shown on the side A and the side B in FIG. 1 in accordance with the pilot pressure. The large diameter part 42 is movably held in a space formed at the front end of the nozzle part 24. The large diameter portion 42 of the second plunger 41 and the large diameter portion 42
A pilot pressure is supplied between the end face 43 and the wall surface 44 of the nozzle portion 24 opposed to the end face 43 via the communication passage 32.
4, a supply chamber 45 is formed.

The wall surface 44 of the nozzle portion 24 and the second
Opposite concave portions 51 and 52 are formed in the end surface 43 of the plunger 41, and between the wall surface 44 and the end surface 43, as shown on the A side in FIG.
A first coil spring 53 is provided as an urging member for urging the second plunger 41 in the distal direction and separating from the wall surface 44 when the plunger 41 is not located near the wall surface 44 when not in operation. , And both ends are positioned in a state of being fitted in the respective concave portions 51 and 52.
The first coil spring 53 is connected to the recess 51,
The case of positioning at 52 has been described as an example, but the present invention is not limited to this. Positioning may be performed by providing a convex portion on which the coil spring 53 is fitted.

At the tip of the second plunger 41,
A small-diameter tubular portion 61 is formed, and a through-hole 62 is provided at the base end of the tubular portion 61 for communicating the inside with the outside. A second coil spring 63 as an urging means is externally fitted to the cylindrical portion 61, and the second coil spring 63 is a stepped portion 64 formed on a peripheral surface of the cylindrical portion 61.
And a stepped portion 66 protruding from the inner surface of the plunger accommodating chamber 65 accommodating the second plunger 63 to urge the second plunger 41 toward the nozzle portion 24. I have. The urging force of the first coil spring 53 and the urging force of the second coil spring 63 are shown in FIG.
As shown on the middle A side, in a state where the gap 67 is formed between the end surface 43 of the second plunger 41 and the wall surface 44 of the nozzle portion 24 during the non-operation, the two urging forces are balanced. The gap 67 is configured to be secured between the wall surface 44 and the second plunger 41 during the non-operation.

In a second valve chamber 71 formed at the end of the second plunger 41, a valve body 73 urged by a spring 72 is movably accommodated.
3 is the second valve chamber 71 and the plunger housing chamber 65
It is configured to be able to open and close the communication hole 74 that communicates with the opening and the opening at the tip of the cylindrical portion 61.

As a result, when the solenoid 21 is not energized, the first input port 25 is closed and the first input port 25 is closed by the first plunger 22 urged by the spring 23 of the sub-valve 11, as shown on the side A in FIG. The drain port 27 is opened to allow air in the supply chamber 45 to flow through the communication passage 32 to the first
It is configured to discharge from the drain port 27,
By moving the second plunger 41 urged by the second coil spring 63 of the main valve 12 toward the proximal end, the communication hole 7 is urged by the valve body 73 urged by the spring 72.
4 is closed so that the pressure of the main output port 81 can be discharged from the second drain port 82 through the plunger housing chamber 65, the cylindrical portion 61 of the second plunger 41, and the through hole 62 of the cylindrical portion 61. Have been.

When the solenoid 21 is energized, the first drain port 27 is closed by the first plunger 22 of the sub-valve 11 and the first input port 25 is opened as shown on the side B in FIG. The pilot pressure is supplied to the inside of the chamber 45. By operating the second plunger 41 of the main valve 12 to the distal end side with the pilot pressure, the valve body 73 is closed while closing the distal end of the cylindrical portion 61. It is configured such that the input pressure from the second input port 83 can be output from the main output port 81 through the communication hole 74 by pressing and moving.

In this embodiment having the above-described configuration, when the solenoid is not energized, the second plunger 4
1 and a wall 44 facing the second plunger 41, a first coil spring 53 is disposed, and the second plunger 41 located near the wall 44 when not in operation.
Is maintained separated from the wall surface 44 by the first coil spring 53. Thereby, the non-contact state between the end face 43 of the second plunger 41 and the wall surface 44 can be ensured, so that the second plunger 41 is stuck to the wall surface 44 by freezing or stuck by an oily adhesive. Can be reliably prevented.

Therefore, the responsiveness when the second plunger 41 is operated by supplying a pilot pressure between the second plunger 41 and the wall surface 44 can be improved. Therefore, characteristics at the start of operation of the solenoid valve 1 can be improved.

Also, as compared with the case where the contact area between the end face 43 of the second plunger 41 and the wall surface 44 is reduced to enhance the characteristics at the time of starting operation, the second plunger 41 comes into contact with the wall surface 44 when returning. The rigidity of the end face 43 can be prevented from being reduced. Thereby, durability can be ensured.

Further, by using the biasing force of the first coil spring 53, the second coil spring 53 is pressed by the pilot pressure.
The movement of the plunger 41 can be assisted. Therefore, the pressing force at the time of operating the second plunger 41 can be increased, which can contribute to improvement of the mobility at the time of operating the second plunger 41.

In addition, the impact when the second plunger 41 comes back into contact with the wall surface 44 can be reduced by the urging force of the first coil spring 53.

In the solenoid valve 1, a second coil spring 63 for urging the second plunger 41 toward the wall surface 44 is provided, so that the second plunger 41 is inactive when not in operation.
The plunger 41 is moved toward the wall surface 43, so that the valve closed state by the valve body 73 can be formed.

At this time, with the gap 67 formed between the second plunger 41 and the wall surface 44, the urging force of the second coil spring 63 and the first plunger provided between the second plunger 41 and the wall surface 44 are provided. Since both biasing forces are set so that the biasing force of the coil spring 53 is balanced, the disadvantage of the return structure using the second coil spring 63 that biases the second plunger 41 toward the wall surface 44 is reliably prevented. can do.

[0029]

As described above, in the solenoid valve according to the first aspect of the present invention, the non-contact state between the end face of the plunger and the wall face facing the end face when not operating can be ensured. . Accordingly, it is possible to reliably prevent the plunger from sticking to the wall surface due to icing or sticking with an oily adhesive.

Therefore, the responsiveness when the plunger is operated by supplying the pilot pressure between the plunger and the wall surface can be improved. Therefore, characteristics at the start of the operation of the solenoid valve can be improved.

Further, as compared with the case where the contact area between the end face of the plunger and the wall surface is reduced to improve the responsiveness,
A decrease in the rigidity of the plunger can be prevented. Thereby, durability can be ensured.

Further, the urging force of the urging member can assist the movement of the plunger pressed by the pilot pressure. For this reason, the pressing force at the time of plunger operation can be increased, and it can contribute to the improvement of the mobility at the time of plunger operation.

In addition, the impact generated toward the wall surface when the plunger returns can be reduced by the urging force of the urging member.

In the solenoid valve according to the second aspect of the present invention, only the urging means for urging the plunger toward the wall surface is provided.
A structure for returning the plunger to the wall surface side during non-operation can be configured.

At this time, in a state where a gap is formed between the plunger and the wall surface, the urging force of the urging means and the urging force of the urging member provided between the plunger wall surfaces are balanced. Since the two urging forces are set in this manner, the disadvantage caused by the provision of the urging means constituting the return structure of the plunger can be surely eliminated.

[Brief description of the drawings]

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

FIG. 2 is a sectional view showing a conventional solenoid valve.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 solenoid valve 11 sub-valve 12 main valve 21 solenoid 22 first plunger 41 second plunger 43 end face 44 wall surface 45 supply chamber 53 first coil spring (biasing member) 63 second coil spring (biasing means) 67 gap

Claims (2)

[Claims] A sub-valve that outputs a pilot pressure in accordance with energization of a solenoid; and a main valve that has a plunger that operates in accordance with the pilot pressure from the sub-valve. An electromagnetic valve having a supply chamber for supplying the pilot pressure formed between the plunger and a wall facing the end face, wherein the plunger is attached when the plunger is not operated near the wall. An electromagnetic valve, wherein an urging member for urging and separating from the wall surface is provided between the plunger and the wall surface. 2. An urging means for urging the plunger toward the wall surface, wherein the urging force of the urging means is provided in a state where a gap is formed between the plunger and the wall surface when the plunger is not operated. 2. The solenoid valve according to claim 1, wherein the two urging forces are set such that the urging force of the urging member is balanced with the urging force of the urging member. 3.