JP2017053475A - solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid valve capable of reducing possibility of leakage of fluid.SOLUTION: A solenoid valve 1 is a solenoid valve provided with an electromagnet 22 for driving a spool 24 arranged inside a valve main body 21. The electromagnet 22 has a tubular member 29, a movable iron core 27 movably stored in an axial direction within the tubular member 29, a fixed iron core 26 fixed at one end of the tubular member 29 and a closing member 30 for closing the other end of the tubular member 29 and having an open hole 30a oppositely facing against the end part of the movable iron core 27. A manual pin 31 is arranged inside the open hole 30a. The open hole 30a is closed by a lid member 11 formed by elastic material in such a way that a tight-sealed space is formed between it and an end part of a side of the manual pin 31 spaced apart from the movable iron core 27.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electromagnetic valve used in, for example, a hydraulic device.

  Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 2000-274547 (Patent Document 1), a solenoid valve is attached to a valve main body provided with a flow path for hydraulic oil and one end of the valve main body. And an electromagnet part.

  The electromagnet portion includes a tubular member, a fixed iron core attached to the end of the tubular member on the valve body side, a movable iron core housed in the tubular member so as to be movable in the axial direction, and the valve body side of the tubular member. And a blocking portion that closes the opposite end. The closed portion is provided with a through hole, and a manual pin is fitted into the through hole.

  In this solenoid valve, during maintenance inspection, the maintenance inspector pushes and moves the manual pin to the movable iron core side. Thereby, a manual pin presses the end surface at the side of the manual pin of a movable iron core, and a movable iron core moves to the fixed iron core side. As a result, even if the electromagnet portion is not energized, the maintenance inspector can manually operate the movable iron core, move the push rod, and move the spool of the solenoid valve.

JP 2000-274547 A

  By the way, when the electromagnet portion is energized when the electromagnetic valve is driven, the movable iron core is attracted to the fixed iron core with the generation of the attractive force between the fixed iron core and the movable iron core. At this time, a negative pressure is likely to be generated in the gap between the movable iron core and the closed portion due to the instantaneous movement of the movable iron core in the tubular member. As a result, due to the differential pressure between the negative pressure in the tubular member and the external atmospheric pressure, a force to be pulled into the tubular member acts on the manual pin. On the other hand, if a back pressure is applied to the tank port provided in the valve body, this back pressure is also transmitted into the tubular member, and thus a force to push out to the manual pin acts. As a result, the manual pin may repeat the movement toward the movable iron core and the movement toward the outside.

  When the movement of the manual pin is repeated, the hydraulic oil attached to the seal member (O-ring) attached to the manual pin may lead to oil leakage to the outside due to the scraping phenomenon. Furthermore, repeated movement of the manual pin may induce wear and peeling of the seal member (O-ring), leading to oil leakage to the outside.

  That is, the conventional solenoid valve has a problem of leakage of hydraulic oil because an unintended movement of the manual pin occurs.

  Accordingly, an object of the present invention is to provide an electromagnetic valve that can reduce the risk of fluid leakage.

  A solenoid valve according to a first aspect of the present invention is an electromagnetic valve provided with an electromagnet that drives a spool disposed inside a valve body, and the electromagnet moves in the axial direction into the tubular member and the tubular member. A movable iron core that can be accommodated, a fixed iron core attached to one end of the tubular member, and a closing member that closes the other end of the tubular member and has a through hole facing the end of the movable iron core A manual pin is disposed inside the through hole, and the through hole forms a sealed space between an end portion of the manual pin on the side away from the movable iron core. It is characterized by being closed by a lid member.

  In this solenoid valve, when the electromagnet is energized, negative pressure is generated in the internal space adjacent to the inner end of the manual pin, and the manual pin tends to be drawn into the solenoid valve. When a negative pressure is generated in the sealed space adjacent to the outer end, the manual pin can be prevented from being drawn into the electromagnetic valve. Therefore, since the manual pin does not move, it is possible to prevent oil leakage due to the working oil scraping phenomenon.

  The solenoid valve according to a second aspect of the present invention is the electromagnetic valve according to the first aspect, wherein the lid member has a valve mechanism that does not allow the outside air to flow into the sealed space and allows the air within the sealed space to flow out. Features.

  In this solenoid valve, when the through hole is closed by the lid member with the manual pin not moved to the outermost side, it is sealed when the pressure in the internal space adjacent to the inner end of the manual pin becomes high. The air in the space can flow out to the outside, and the manual pin is configured to be movable outward. Therefore, when the pressure in the internal space adjacent to the inner end of the manual pin is increased, the air in the sealed space is compressed by the force with which the manual pin is pushed outward, and the lid member can be prevented from coming off from the closing member. . Thereafter, the manual pin is fixed in a state where it is moved to the outermost side, and the manual pin does not move. Therefore, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon.

  A solenoid valve according to a third aspect is the electromagnetic valve according to the second aspect, wherein the lid member is formed of an elastic material, and is closed as the valve mechanism when the pressure of the sealed space is lower than the external pressure, and the sealed space. It has a hole that is opened when the pressure of is higher than the external pressure.

  This solenoid valve can be easily configured with a valve mechanism that allows the sealed space to communicate with the outside only when the pressure in the sealed space is higher than the outside air pressure. Oil leakage due to the scraping phenomenon can be prevented.

  A solenoid valve according to a fourth invention is characterized in that, in the third invention, the lid member has a notch formed in an inner surface thereof, and the hole is formed in a bottom portion of the notch. And

  In this solenoid valve, when the pressure in the sealed space is lower than the external pressure, it is possible to more effectively prevent the air from flowing into the sealed space from outside air. Accordingly, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon in a state where the manual pin is fixed in a state where it is moved to the outermost side.

  A solenoid valve according to a fifth aspect is the electromagnetic valve according to the second aspect, wherein the lid member is formed of an elastic material, and the valve mechanism is a closed state in which the sealed space is closed when the pressure of the sealed space is lower than the external pressure. And a valve member capable of opening the sealed space when the pressure in the sealed space is higher than the external pressure.

  In this solenoid valve, a valve mechanism that allows the sealed space to communicate with the outside through a large opening only when the pressure in the sealed space is higher than the external pressure can be easily configured, and the manual pin is fixed in a state where it moves to the outermost side. In this state, it is possible to prevent oil leakage due to the working oil scraping phenomenon.

In the first invention, when the electromagnet is energized, negative pressure is generated in the internal space adjacent to the inner end of the manual pin, and the manual pin tends to be drawn into the solenoid valve. When the negative pressure is generated in the sealed space adjacent to the outer end of the manual pin, the manual pin can be prevented from being pulled into the electromagnetic valve. Therefore, since the manual pin does not move, it is possible to prevent oil leakage due to the working oil scraping phenomenon.
In the second invention, when the through hole is closed by the lid member in a state where the manual pin is not moved to the outermost side, when the pressure in the internal space adjacent to the inner end of the manual pin becomes high, The air in the sealed space can flow out to the outside, and the manual pin can be moved outward. Therefore, when the pressure in the internal space adjacent to the inner end of the manual pin is increased, the air in the sealed space is compressed by the force with which the manual pin is pushed outward, and the lid member can be prevented from coming off from the closing member. . Thereafter, the manual pin is fixed in a state where it is moved to the outermost side, and the manual pin does not move. Therefore, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon.
In the third invention, the valve mechanism that allows the sealed space to communicate with the outside only when the pressure of the sealed space is higher than the outside air pressure can be easily configured, and the manual pin is operated in a state where it is fixed in a state of being moved to the outermost side. Oil leakage due to oil scraping can be prevented.
In 4th invention, when the pressure of sealed space is lower than external atmospheric pressure, it can prevent more effectively that it flows in into sealed space from external air. Accordingly, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon in a state where the manual pin is fixed in a state where it is moved to the outermost side.
According to the fifth aspect of the invention, a valve mechanism that allows the sealed space to communicate with the outside through a large opening can be easily configured only when the pressure in the sealed space is higher than the external pressure, and the manual pin is fixed in a state where the manual pin has moved to the outermost side. In this state, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon.

It is a schematic front view of the solenoid valve of the embodiment of the present invention. It is a schematic sectional drawing of the stopper of the solenoid valve of FIG. 1, and its peripheral part. It is a schematic sectional drawing of the stopper of the solenoid valve of the modification of this invention, and its peripheral part. It is a schematic sectional drawing of the stopper of the solenoid valve of the modification of this invention, and its peripheral part. It is a schematic sectional drawing of the stopper of the solenoid valve of the modification of this invention, and its peripheral part. It is a schematic sectional drawing of the stopper of the solenoid valve of the modification of this invention, and its peripheral part.

  Hereinafter, the solenoid valve of the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1 is a schematic front view of a solenoid valve according to an embodiment of the present invention. In addition, in FIG. 1, in order to make it easy to understand the structure of a solenoid valve, the principal part is shown with a cross section.

  The electromagnetic valve 1 includes a valve body 21 that accommodates the spool 24 so as to be movable in the axial direction, first and second electromagnet portions 22 and 23 for moving the spool 24 in the axial direction, and a manual pin 31. Control the flow of hydraulic fluid.

  The valve body 21 is formed with a through hole 21a extending in the left-right direction in FIG. A spool 24 that moves in the axial direction of the through hole 21a and switches the flow path of the hydraulic oil is inserted into the through hole 21a. In addition, a hydraulic oil supply channel P, a first load channel A, a second load channel B, and a discharge channel C are provided on the inner surface of the through hole 21a. Further, on the outer surface of the spool 24, a land 25 formed of an annular projecting portion is formed. The spool 24 moves in the through hole 21 a in the axial direction and controls communication between the flow paths P, A, B, and C by the land 25.

  A screw hole 21b is formed at one end of the valve body 21 coaxially with the through hole 21a. The first electromagnet portion 22 is attached to one end portion of the valve body 21 by screwing a fixed iron core 26 provided at one end portion of the first electromagnet portion 22 into the screw hole 21b.

  A second electromagnet portion 23 is attached to the other end portion of the valve body 21 opposite to the one end portion in the same manner as the first electromagnet portion 22. The first electromagnet part 22 and the second electromagnet part 23 have exactly the same configuration. Therefore, in the following description, the description of the configuration of the second electromagnet unit 23 is omitted.

  The first electromagnet portion 22 includes a casing 35, a tubular member 29 disposed in the casing 35, a movable iron core 27 accommodated in the tubular member 29 so as to be movable in the axial direction, and one end of the tubular member 29. A fixed iron core 26 attached, a stopper 30 provided to close the other end opposite to the one end of the tubular member 29, and a coil 28 installed around the fixed iron core 26 and the movable iron core 27 are provided. Yes. The stopper 30 is an example of a closing part.

  A step portion 26 a is formed on the outer peripheral surface of the end portion of the fixed iron core 26 on the movable iron core side. One end of the tubular member 29 is fitted coaxially with the fixed iron core 26 to the stepped portion 26a, and is joined by welding. A stopper 30 is attached to the other end of the tubular member 29 opposite to the one end. Further, a columnar movable iron core 27 is slidably accommodated in the tubular member 29. That is, the spool 24 and the movable iron core 27 are movable on the same axis.

  The movable iron core 27 is located on the opposite side of the fixed iron core 26 from the valve body 21 and is attracted to the fixed iron core 26. One end of a push rod 31 is attached to the end surface of the movable iron core 27 on the fixed iron core 26 side. Further, the fixed iron core 26 is formed with a through hole 26 b coaxially with the through hole 21 a of the valve body 21, and the push rod 31 is inserted into the through hole 26 b so that the spool 24 has a first magnet portion 22 side. It is in contact with the end face. The spool 24 can move by the same distance in the same direction as the movable core 27 as the movable core 27 moves.

  The stopper 30 is formed with a through hole 30 a that faces the movable iron core 27. A nut member 36 is screwed onto the stopper 30, and the casing 35 is sandwiched between the valve body 21 and the nut member 36 by tightening the nut member 36.

  FIG. 2 is a schematic cross-sectional view of the stopper 30 and its peripheral part.

  As shown in FIGS. 1 and 2, the manual pin 31 is fitted into the through hole 30a, and the end 31a of the manual pin 31 opposite to the movable iron core 27 is disposed inside the through hole 30a. An annular groove 32 is formed on the outer peripheral surface of the manual pin 31, and a seal member is fitted in the annular groove 32. At the end portion of the stopper 30 (right end portion in FIG. 2), the through hole 30a is sealed between the end portion 31a of the manual pin 31 away from the movable core 27 by the lid member 11 (see FIG. 2). It is closed so that a hatched portion is formed.

  The lid member 11 has two plate-like members 11a and 11b made of an elastic material. The two plate-like members 11a and 11b are circular and are joined by an adhesive or the like. The outer plate-like member 11a has a hole 12 formed in the approximate center thereof, and the inner plate-like member 11b has a notch 13 formed around the hole 12, and the hole 12 is notched. 13 is formed to be able to communicate with the bottom portion. Therefore, the notch 13 is formed in a substantially circular shape formed on the inner surface of the lid member 11.

  The hole 12 of the lid member 11 is configured to be closed when the pressure in the sealed space D is lower than the external pressure, and to be opened when the pressure in the sealed space D is higher than the external pressure. Therefore, the hole 12 is configured as a valve mechanism that does not allow external air to flow into the sealed space D and allows the air within the sealed space D to flow out.

<Characteristics of solenoid valve of this embodiment>
The solenoid valve 1 of the present embodiment has the following characteristics.

  In the electromagnetic valve 1 of the present embodiment, when the electromagnet portion 22 is energized, negative pressure is generated in the internal space adjacent to the inner end of the manual pin 31, and the manual pin 31 tends to be drawn into the electromagnetic valve 1. However, at this time, a negative pressure is generated in the sealed space D adjacent to the outer end portion 31a of the manual pin 31, so that a negative pressure is generated in both the inner end portion and the outer end portion 31a of the manual pin 31. Therefore, the force to be pulled into the solenoid valve 1 does not act on the manual pin 31. Therefore, the manual pin 31 can be prevented from being pulled into the electromagnetic valve 1, and oil leakage due to the working oil scraping phenomenon can be prevented.

  In the electromagnetic valve 1 of the present embodiment, since the lid member 11 has a valve mechanism that does not allow external air to flow into the sealed space D and allows the air within the sealed space D to flow out, the manual pin 31 is When the through-hole 30a is closed by the lid member 11 in a state where it is not moved to the outermost side, the air in the sealed space D is increased when the pressure in the internal space adjacent to the inner end of the manual pin 31 becomes high. Can flow out, and the manual pin 31 is configured to be movable outward. Therefore, when the pressure in the internal space adjacent to the inner end of the manual pin 31 increases, the air in the sealed space D is compressed by the force with which the manual pin 31 is pushed outward, and the lid member 11 is released from the stopper 30. Can be prevented. Thereafter, the manual pin 31 is fixed in a state where it is moved to the outermost side, and the manual pin 31 does not move. Therefore, it is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon.

  In the electromagnetic valve 1 of the present embodiment, the lid member 11 is formed of an elastic material, and is closed as a valve mechanism when the pressure in the sealed space is lower than the external pressure, and when the pressure in the sealed space is higher than the external pressure. Since it has the hole 12 opened to the outside, the valve mechanism that allows the sealed space D to communicate with the outside only when the pressure of the sealed space D is higher than the outside air pressure can be easily configured, and the manual pin 31 has moved to the outermost side. It is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon in the fixed state.

  In the electromagnetic valve 1 of the present embodiment, the lid member 11 has a notch 13 formed on the inner surface thereof, and the hole 12 is formed so as to be able to communicate with the bottom of the notch 13. It is possible to more effectively prevent the air from flowing into the sealed space D from the outside air when the pressure is lower than the external pressure. Therefore, it is possible to prevent the oil leakage due to the hydraulic oil scraping phenomenon from occurring in a state where the manual pin 31 is fixed in a state of moving to the outermost side.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims. It is.

  In the above-described embodiment, the case where the lid member 11 is configured by joining two plate-like members 11a and 11b has been described. However, as shown in FIG. 3, the lid member 111 is a single plate-like member. May be configured. In the lid member 111 of FIG. 3, as with the lid member 11, the hole 112 is closed when the pressure in the sealed space D is lower than the external pressure, and is opened when the pressure in the sealed space D is higher than the external pressure. Configured to be Accordingly, the hole 112 is configured as a valve mechanism that does not allow external air to flow into the sealed space D and allows the air within the sealed space D to flow out. A notch 113 is formed on the inner surface of the lid member 111, and its cross-sectional area increases as the distance from the hole 112 increases.

  When the lid member 111 is bent, the center is pulled from one central portion in the thickness direction, and the other is compressed. When the external air pressure is higher than the pressure in the sealed space D (when the manual pin 31 is pulled into the electromagnetic valve 1), the lid member 111 is deformed so as to protrude toward the inside of the electromagnetic valve, and the inner portion of the lid member 111 The tensioning action is applied to the cover member 111 and the compression action is applied to the outer portion of the lid member 111. Therefore, a force for expanding the notch 113 acts on the inner part of the lid member 111, and a force for reducing the hole 112 acts on the outer part of the lid member 111. Therefore, it is possible to prevent outside air from flowing into the sealed space D from the external space.

  On the other hand, when the pressure in the sealed space D is higher than the external pressure (when the manual pin 31 is pushed out of the electromagnetic valve), the lid member 111 is deformed so as to protrude outward from the electromagnetic valve, and the lid member 111 A compressing action is applied to the inner part of the cover member and a tensile action is applied to the outer part of the lid member 111. Therefore, a force for reducing the notch 113 acts on the inner part of the lid member 111, and a force for enlarging the hole 112 acts on the outer part of the lid member 111. Therefore, the outside air easily flows out from the sealed space D to the external space. At this time, a force for reducing the notch 113 acts on the inner portion of the lid member 111, but the notch 113 is not blocked.

  In the above-described embodiment, the lid member 11 is formed of an elastic material, and is closed as a valve mechanism when the pressure of the sealed space D is lower than the external pressure, and when the pressure of the sealed space D is higher than the external pressure. Although the case where it has the hole 12 opened was demonstrated, as shown in FIG. 4, when the cover member 211 is formed with an elastic material and the pressure of the sealed space D is lower than the external pressure as a valve mechanism, the sealed space D And a valve member 212 that can be in an open state in which the sealed space D is opened when the pressure in the sealed space D is higher than the external atmospheric pressure. In the lid member 211 in FIG. 4, the opening 213 can be closed or opened by the valve member 212. In this solenoid valve, a valve mechanism that allows the sealed space D to communicate with the outside through a large opening can be easily configured only when the pressure in the sealed space D is higher than the external pressure, and the manual pin 31 is moved to the outermost side. It is possible to prevent oil leakage due to the hydraulic oil scraping phenomenon in a fixed state.

  A lid member 311 similar to the lid member 211 of FIG. 4 may be configured by joining two plate-like members 311a and 311b as shown in FIG. In the lid member 311 of FIG. 5, the upper half of the outer plate-like member 311a is joined to the inner plate-like member 311b, and the lower half of the outer plate-like member 311a is not joined to the inner plate-like member 311b. Therefore, the lower half of the outer plate-shaped member 311a is configured to be able to close or open the opening 313, like the valve member 212 of FIG.

  In the above-described embodiment, the case where the through hole 30a is closed by disposing the lid member 11 outside the end portion of the stopper 30 has been described, but as shown in FIG. The through hole 30a may be closed by disposing a part of the lid member 411 inside the through hole 30a. The lid member 411 of FIG. 6 is formed of an elastic material, and as a valve mechanism, the closed space D is closed when the pressure of the sealed space D is lower than the external pressure, and the pressure of the sealed space D is the external pressure. You may have the valve member 412 which can be in the open state which opens the sealed space D when it is higher. In the lid member 411 of FIG. 6, the opening 413 can be closed or opened by the valve member 412.

  In the above-described embodiment, the case has been described in which the lid member has a valve mechanism that does not allow external air to flow into the sealed space and outflows the air in the sealed space to the outside. However, the lid member has a valve mechanism. It may not be. When the through hole 30a is closed by the lid member with the manual pin 31 not moved to the outermost side, the lid member may not have a valve mechanism.

DESCRIPTION OF SYMBOLS 1, Solenoid valve 11, 111, 211, 311, 411 Cover member 12, 112 Hole 13, 113, 213, 313, 413 Notch 21 Valve body 22 1st electromagnet part 23 2nd electromagnet part 24 Spool 26 Fixed iron core 27 Movable Iron core 29 Tubular member 30 Stopper 30a Through hole 31 Manual pin 33 Seal member (O-ring)
212, 312, 412 Valve member

Claims (5)

An electromagnetic valve having an electromagnet for driving a spool disposed inside the valve body,
The electromagnet
A tubular member;
A movable iron core movably accommodated in the axial direction inside the tubular member;
A fixed iron core attached to one end of the tubular member;
The other end of the tubular member is closed, and a closing member having a through hole facing the end of the movable iron core,
A manual pin is arranged inside the through hole,
The electromagnetic valve according to claim 1, wherein the through hole is closed by a lid member so that a sealed space is formed between an end portion of the manual pin that is away from the movable iron core.   The electromagnetic valve according to claim 1, wherein the lid member has a valve mechanism that does not allow external air to flow into the sealed space and allows the air within the sealed space to flow out. The lid member is formed of an elastic material,
The electromagnetic mechanism according to claim 2, wherein the valve mechanism has a hole that is closed when the pressure in the sealed space is lower than the external pressure, and is opened when the pressure in the sealed space is higher than the external pressure. valve. The lid member has a notch formed on the inner surface thereof,
The solenoid valve according to claim 3, wherein the hole is formed in a bottom portion of the notch. The lid member is formed of an elastic material,
As the valve mechanism, a valve member that can be in a closed state that closes the sealed space when the pressure in the sealed space is lower than the external pressure, and that can be in an open state that opens the sealed space when the pressure in the sealed space is higher than the external pressure. The electromagnetic valve according to claim 2, wherein the electromagnetic valve is provided.

Images