WO2006090916A1

WO2006090916A1 - Electromagnetic drive valve

Info

Publication number: WO2006090916A1
Application number: PCT/JP2006/304178
Authority: WO
Inventors: Hideo Suyama; Hideki Ooshima; Kazusada Imai
Original assignee: Kabushikikaisya Advance
Priority date: 2005-02-28
Filing date: 2006-02-27
Publication date: 2006-08-31
Also published as: JPWO2006090916A1

Abstract

An electromagnetic drive valve has a cylindrical coil having an external circumferential portion and a bottom portion which are covered by a first magnetic plate. A cylindrical second magnetic body continuous to the first magnetic plate is arranged at the center of, i.e., inside the cylindrical coil. An annular gap is formed with an outer diameter defined by a circular hole at the center of a third magnetic plate arranged continuously with the bottom portion and the opposite end portion of the first magnetic plate and an inner diameter defined by the external circumference of the second cylindrical magnetic body. A circular fourth magnetic plate is movably arranged to oppose to the annular gap, thereby constituting a solenoid housing. Furthermore, the circular fourth magnetic plate is fixed to the end of the extended portion of the piston rod. The electromagnetic drive valve has a low noise level and a simple structure of the drive unit and can be employed, for example, in a massaging tool using an air pressure.

Description

Description Electromagnetically operated valve

Technical field

The present invention relates to an electromagnetically driven valve. More specifically, the present invention relates to an electromagnetically driven valve in which the structure of a drive unit is improved.

Background art

There are massage machines as health equipment, and various types of massage machines are currently being promoted. For example, there is a massaging machine that uses air pressure. In this massaging machine, an electromagnetically driven valve is used to switch the flow path of a relatively large flow rate of air. Three-way valves are mainly used as electromagnetically driven valves. The three-way valve is a valve that is energized to send air from the pump to the air bag.

Equipped with a mechanism that opens in one direction by driving in one direction, returns the valve in the opposite direction when demagnetized, shuts off the pump, and opens the other flow path to reduce or maintain the air pressure in the air bag. ing. The air bags are arranged at a plurality of locations, and in some cases, the opening and closing of the valve is repeated with a relatively short cycle similar to the biological pulse wave.

An example of a three-way valve used in a conventional electromagnetically driven valve is the electromagnetically driven valve shown in FIG. In the case of this electromagnetically driven valve, the pump port

5 8, Air bag port 5 9 and Leak port 60 Select the three fluid inlet / outlet flow paths by using the upper and lower annular rubber of the valve section 6 2 of the piston rod 6 1 〇 Ring 6 3, 6 4 Is selectively applied to the valve seats 6 7 and 6 8 of the casing 6 6 of the valve housing 6 5. When piston rod 6 1 is excited, solenoid housing 6 9 is energized. 6 8 and the pump port 5 8 and the air bag port 5 9 form a flow path. On the other hand, when demagnetizing, the piston rod 6 1 returns with the force of the spring 70, and the ring 6 3 hits the valve seat 6 7 Thus, a flow path is formed by the air bag port 59 and the leak port 60. The rubber U-ring 71 is for securing a seal when the piston rod 61 moves through the circular hollow portion 72 of the casing 66.

The solenoid housing 6 9 for driving the piston rod 6 1 has a magnetic plate yoke 部 5 covering the outer periphery and bottom of the coil 7 4 formed on the pobbin 73 and magnetically continuing to the center of the bottom. A non-magnetic, slidable magnetic plate 7 7 with a circular hole in the center is placed in a continuous manner with the fixed iron core 7 6 at the end opposite to the bottom of the cylinder 75. A cylindrical magnetic plunger 7 9 is movably disposed in a thin sleeve tube 7 8. The main magnetic gap is formed between the plunger 7 9 and the fixed iron core 7 6. When the coil 7 4 is excited, the plunger 7 9 is fixed to the fixed iron core.

The piston rod 6 1 is attracted by 7 6 and pushes the piston rod 6 1. At the time of demagnetization, the piston port 6 1 is returned by the repulsive force of the spring 70.

By the way, the non-magnetic rod 80 and the piston rod 61 integrated with the plunger 7 9 are difficult to fix, so the repulsive force of the spring 70 during demagnetization causes the plunger 7 9 Noise occurs when rod 8 0 leaves and collides with piston rod 6 1. Also, in order to slide the plunger 7 9, it is necessary to ensure the durability of the sleeve tube 7 8 and the plunger 7 9, and the magnetic blanker 7 9 and the non-magnetic rod 8 0 are required. These integrated parts are also required. In addition, since the valve housing 6 5 and the solenoid housing 6 9 are separated from each other, it is necessary to install parts and processes for use.

To quote for reference, Japanese Patent Application Laid-Open No. Hei 10 — 3 3 2 0 4 discloses that a single electromagnetic coil has a plurality of wars without the occurrence of a hammer phenomenon. A flow path switching valve that can alternately switch to a flow path at high speed is disclosed in Japanese Patent Publication No. 2 0 0 3 — 2 6 9 6 4 5, respectively. Disclosure of the invention

The first object of the present invention is to reduce the level of noise generation in an electromagnetically driven valve. Another object of the present invention is to simplify the configuration of the electromagnetic drive unit, improve operability and reduce costs. These and other objects of the present invention will be readily understood from the following detailed description.

According to the present invention, these objects are achieved by covering the outer peripheral portion and the bottom portion of the cylindrical coil with the first magnetic plate, and continuing to the first magnetic plate, the second cylindrical magnetic member. Is arranged inside the center of the cylindrical coil, and the circular hole in the center of the third magnetic plate arranged continuously from the end opposite to the bottom of the first magnetic plate. An annular gap having an outer diameter as the outer diameter and an outer circumference of the cylindrical second magnetic body as an inner diameter is formed, and the circular fourth magnetic plate is movable so as to face the annular gap. This is achieved by an electromagnetically driven valve characterized in that it forms a solenoid housing, and a circular fourth magnetic plate is fixed to the end of the piston port extension. Can do.

In the electromagnetically driven valve according to the present invention, the yoke of the first magnetic plate covering the outer peripheral portion and the bottom portion of the cylindrical coil is magnetically continuous between the yoke and the central portion of the bottom portion, and inside the cylindrical coil. The magnetic core of the second cylindrical magnetic body is magnetically continuous from the end opposite to the bottom of the yoke, and the third magnetic plate having a circular hole in the center is formed. A magnetic circuit is formed in which an annular gap having an inner diameter as an outer diameter and a circular outer periphery of a central iron core as an inner diameter is arranged. There is space in this annular gap. Then, a solenoid housing is constructed by disposing a plate-shaped blanker of a circular fourth magnetic plate facing each other in parallel. Fix this plate-like plunger to the end of the extension of the piston rod on the valve housing. The piston rod has a valve, and the movement of the fluid is controlled by opening and closing the valve by the movement of the piston rod. The piston rod is driven by the excitation of the coil and returns by the repulsive force of the spring.

In the electromagnetically driven valve according to the present invention, the plate-like plunger that receives the driving force by exciting the solenoid housing coil is fixed to the end of the piston rod having the valve portion. There is no separation of the plunger and piston rod when returning due to the repulsive force of the cylinder, and no noise is generated by the collision. During excitation and demagnetization, the ring rubber of the valve part is relaxed by the contact with the ring and the valve seat part. Since the corresponding part is inside the valve housing, there is little noise generation. Therefore, the electromagnetically driven valve of the present invention can be advantageously used, for example, in a massaging machine using one air pressure.

In addition, the electromagnetically driven valve of the present invention can quietly open and close at least the same period as the period of the biological pulse wave, so that during the heart activity, a pneumatic stimulus is applied during diastole. Can be effectively used as a home medical device that applies suction air pressure during the systole.

Further, in the electromagnetically driven valve of the present invention, a circular magnetic body plate has the role of a conventional plunger, and the sliding and central positioning of the plunger is performed in the hollow portion of the casing of the valve portion. The solenoid-operated valve of the present invention can simplify the structure of the plunger housing sliding portion of the solenoid housing because it can be formed by a circular protrusion on the wall surface or a thick outer peripheral portion of the end of the piston rod. So, the solenoid housing and valve Since the housing is integrated, there is no need for parts and strokes to incorporate the solenoid housing and valve housing independently when used as an electromagnetically driven valve.

Furthermore, in the electromagnetically driven valve according to the present invention, adjustments such as increasing the driving force as the electromagnetically driven valve can be easily made by providing an annular step portion on the plate-like plunger of the circular magnetic plate. Brief Description of Drawings

FIG. 1 is a sectional view showing a conventional electromagnetically driven valve,

FIG. 2 is a sectional view of the electromagnetically driven valve according to the first embodiment of the present invention,

FIG. 3 is a sectional view of an electromagnetically driven valve according to a second embodiment of the present invention, and

FIG. 4 is a sectional view of an electromagnetically driven valve according to a third embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

The electromagnetically driven valve according to the present invention can be advantageously implemented in various forms. The preferred embodiments of the present invention will be described below. As described above, the electromagnetically driven valve of the present invention covers the outer peripheral portion and the bottom portion of the cylindrical coil with the first magnetic plate, and the cylindrical second magnetic layer is continuous with the first magnetic plate. The body is arranged inside the center of the cylindrical coil, and the circular shape at the center of the third magnetic plate arranged continuously from the end opposite to the bottom of the first magnetic plate. An annular gap is formed with the hole as the outer diameter and the outer circumference of the cylindrical second magnetic body as the inner diameter, and the circular fourth magnetic plate is movable so as to face the annular gap. To form a solenoid housing, and a circular fourth magnetic plate It is fixed to the end of the extension of the tonrod.

Referring to FIG. 2, the electromagnetically driven valve according to the present invention includes a solenoid housing 1 that is an electromagnetically driven portion, and a yoke of a first magnetic plate in which the outer peripheral portion and the bottom portion of a cylindrical coil 2 are bent. A cylindrical second magnetic core 4 covered with 3 and magnetically continuous with the central portion of the bottom of the yoke 3 of the first magnetic plate is disposed inside the cylindrical coil 2. Also, a third magnetic plate 5 having a circular hole in the center from the end opposite to the bottom of the yoke 3 of the first magnetic plate is arranged magnetically continuously. Is formed as an annular gap 6 having an outer diameter and an outer periphery of the iron core 4 of the cylindrical second magnetic body as an inner diameter. Furthermore, a plate-shaped plunger 7 of a circular magnetic plate 4 is movably disposed at a position facing the annular gap 6 in parallel with the space, and the plate-shaped plunger 7 is connected to the valve portion 8. Secure to the end of the extension 20 of the piston rod 9 that you have.

In the implementation of the present invention, the electromagnetically driven valve is composed of a piston rod having an annular rubber in the upper and lower valve portions, a swing for applying force to the piston rod, and a valve having a three fluid inlet / outlet. Is preferred.

That is, in the case of this embodiment, the solenoid housing 1 shown in FIG. 2 is used, and the valve housing 10 has annular rings O rings 11 and 12 above and below the valve portion 8 of the piston rod 9. The flow path is switched by three fluid inlets 14, 15, and 16 by the driving force when the cylindrical coil 2 is excited and the repulsive force of the spring 13 when demagnetizing.

In the electromagnetically driven valve of the present invention, an annular step portion having an outer diameter smaller than the outer diameter of the annular gap and an inner diameter larger than the inner diameter of the annular gap is formed on the circular fourth magnetic plate. It is preferably formed on the annular gap side.

That is, in the case of this form, the circular fourth magnetic body shown in FIG. An annular stepped portion 18 is formed on the plate-like plunger 17 shown in FIG. 3 corresponding to the plate-like plunger 7 of the plate, and is opposed to the annular gap 19 corresponding to the annular gap 6. Close. The annular step portion 18 is configured to have an outer diameter smaller than the outer diameter of the annular gap 19 and an inner diameter larger than the inner diameter of the annular gap 19.

Further, in the electromagnetically driven valve according to the present invention, a non-circular projection is provided at the end of the extension portion of the piston rod, and the non-circular hole is formed at the center of the disc-shaped fourth magnetic plate. It is preferable that the protrusion is fitted and supported on the protrusion.

That is, in the case of this configuration, the plate-shaped plunger 7 of the circular fourth magnetic body shown in FIG. 2 is fixed to the end of the piston rod 9, and the extension 2 of the piston port 9 The non-circular protrusion 2 1 at the end of 0 is configured to fit and support the approximate non-circular hole at the center of the plate-like plunger 7.

Furthermore, in the case of the electromagnetically driven valve according to the present invention, a circular protrusion larger than the outer diameter of the piston rod is formed on the inner wall surface of the hollow portion of the casing of the valve housing at a position between the piston rod and its extension. It is preferable that it is slidable.

That is, in this configuration, the piston lodge is located on the inner wall surface of the hollow portion 2 3 of the casing 2 2 of the valve housing 10 at a position between the piston rod 9 and its extension 20 shown in FIG. Provide circular protrusions 24 that are larger than the outer diameter of cylinder 9, and slide piston rod 9 and center it.

Furthermore, in the case of the electromagnetically driven valve of the present invention, the outer diameter near the end of the extension portion of the piston rod has an increased size that approximates the inner diameter of the cylindrical second magnetic body. It is preferable to configure.

That is, in this configuration, the piston rod 9 shown in FIG. Corresponding to the core 2 of the cylindrical second magnetic body shown in Fig. 2, with the outer diameter of the portion 2 7 near the end of the extension 26 of the piston rod 25 shown in Fig. 4 corresponding to the extension 2 26 Position the center of the piston rod 25 in a shape that approximates the inner diameter of the iron core 28 shown in Fig. 4.

Furthermore, in the case of the electromagnetically driven valve of the present invention, the first magnetic plate of the solenoid housing is formed in a U shape, and the width in the direction having the U-shaped surface is the width in the direction not having the U-shaped surface. It is preferable that the solenoid housing is fixed by providing an L-shaped fixing portion in parallel to the valve housing casing in parallel.

That is, in the case of this configuration, the yoke 51 of the solenoid housing 50 of FIG. 4 corresponding to the solenoid 8 uzaging 1 of FIG. 2 is formed in a U-shape, and the width in the direction having the U-shaped surface is increased. Larger than the width in the direction that does not have a U-shaped surface, L-shaped fixed part that protrudes continuously from the top of the casing 4 of the valve 8 housing 4 corresponding to the solenoid 8 housing 5 4 5 4 , 5 5 are arranged in parallel, and the solenoid and housing

5 Fix 0

Subsequently, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

First embodiment

FIG. 2 shows a first embodiment of the electromagnetically driven valve of the present invention. In the figure, for the sake of simplicity, the electromagnetically driven valve is shown in cross section, excluding screws 9 and screws.

A solenoid housing 1 that provides the driving force of an electromagnetically driven valve is formed by covering the outer periphery and bottom of a cylindrical coil 2 wound around a povin 31 with a yoke 3 of a first magnetic plate. Insert an iron core 4 made of a cylindrical second magnetic body that is magnetically continuous in the center of the inside of the pobin 3 1 around which the cylindrical coil 2 is wound, and further opposite the bottom of the yoke 3 Place a plate 5 consisting of a third magnetic plate that is magnetically continuous from the end of the side (upper), place a circular hole in the center of this plate 5 on the outer periphery, and the outer periphery of the iron core 4 on the inner diameter. A magnetic circuit is formed by an annular gap 6 as follows.

A plate-like plunger 7 of a circular fourth magnetic plate is opposed to the annular gap 6 in parallel, and is movably arranged through a space. The plate-like plunger 7 has a non-circular projection 2 1 at the upper end of the extension 20 of the piston rod 9 of the valve housing 10 and a non-circular approximate hole of the plate-like plunger 7. The screw 3 2 is fixed with a washer and fixed partially with an adhesive, so that the screw 3 2 does not loosen during vibration, and the plate-shaped plunger 7 and the piston rod 9 move together. Become.

When the cylindrical coil 2 is energized, the solenoid housing 1 is excited and a relatively strong magnetic field is generated in the space near the annular gap 6. A plate-like plunger 7, which is a magnetic body arranged close to the annular gap 6 through a space, receives an electromagnetic driving force attracted in the direction of the annular gap 6. When this electromagnetic driving force becomes considerably larger than the repulsive force of the spring 13, the piston rod 9 is driven, and a communication channel is formed between the fluid inlet / outlet 14 and the fluid inlet / outlet 15, for example, at the fluid inlet / outlet 14. When a positive pressure pump is connected via a conduit and an air bag (stimulation cuff) is connected to the fluid inlet / outlet 15 via a conduit, the positive air pressure output by the positive pressure pump is introduced into the air bag. As a result, the internal pressure of the air bag increases and the air bag expands greatly. For example, when this electromagnetically driven valve is used in combination with a living body and an air bag, the air bag in contact with the living body swells so that the living body feels pressure (stimulation) to be pressed. If the coil 2 is turned off and demagnetized, the electromagnetic driving force is lost, and the piston rod 9 returns due to the repulsive force of the spring 1 3, as shown in Fig. 2. As shown, an annular rubber O-ring 11 is brought into contact with the valve seat portion 34 to form a flow path between the fluid inlet / outlet port 15 and the fluid inlet / outlet port 16.

For example, if an air bag is connected to the fluid inlet / outlet 15 via a conduit and the fluid inlet / outlet 16 is connected to the atmosphere, the high pressure of the air bag is released via the fluid inlet / outlet 16 and the air bag It will be reduced. The pump pressure connected to the fluid inlet / outlet 14 is sealed with a circular rubber U-ring 35 and 〇 ring 1 1 to cut off the connection between the fluid inlet / outlet 14 and the fluid inlet / outlet 15. The The U-ring 35 has a function of sealing while sliding the circular hollow portion 2 3 of the casing 2 2.

The piston rod 9 driven by electromagnetic driving force is stopped when the ring 1 2 made of the annular rubber of the valve part 8 hits the valve seat part 3 3 of the resin casing 3 6 and the repulsive force of the spring 1 3 When returning, the ring rubber O-ring 1 1 stops when it hits the valve seat 3 4 of the resin casing 2 2.

As described above, the casings 2 2 and 3 6 made of resin are joined to each other through the sealing material so that the valve portion 8 is annularly connected to the upper and lower valve seats 3 3 and 3 4 in the inner space of the valve housing 10. Since the collision and stop are repeated via the rubber 1 1 and 1 2, the level of noise generated outside becomes small.

The piston rod 9 is centered on one side by the circular recess 3 6a of the casing 3 6 of the valve housing 10, and the circular hollow portion 2 3 of the casing 2 2 has a circular shape on the inner wall surface. The center of positioning between the piston rod 9 and the extended portion 20 is centered by the projections 24 of the piston rod 9 so that the center of the piston rod 9 can be positioned as a whole. It is recommended to make a notch in a part of the circular protrusion 2 4 to make air pressure leak easily. The piston rod 9 can be positioned by forming and processing the piston rod 9 of the valve housing 10 and the casings 2 2 and 3 6.

The solenoid housing 1 is fixed to the L-shaped fixed part 3 7, 3 8 from the housing 2 2 of the valve housing 10 with screws 3 9, 40, The whole electromagnetically driven valve is assembled by fixing the plate-like plunger 7 to the end of the extension 20 of the piston rod 9 inserted into the valve housing 10.

In this embodiment, as an example, the distance between the plate-like plunger 7 and the plate 5 is, for example, around 1.0 to 1.3 mm, and the thickness of the plate-like plunger 7 is, for example, 1.0 to 1 The width of the annular gap 6 is, for example, about 2.5 to 3.0 mm. Of course, in some cases, sizes outside the above range are also applicable in this embodiment.

Second embodiment

FIG. 3 shows a second embodiment of the electromagnetically driven valve of the present invention. In the figure, the solenoid-operated valve is shown in cross section, excluding the piston rod 41 and screws, for the sake of simplicity.

The electromagnetically driven valve is different from the first embodiment described above with reference to FIG. 2 in that a plate-shaped blanker 17 corresponding to a circular fourth magnetic plate has an annular stepped portion 18. It is to have established. The outer diameter of the annular step portion 18 is smaller than the outer diameter of the annular gap 19, the inner diameter of the annular step portion 18 is larger than the inner diameter of the annular gap 19, and the center axis is mutually Commonly facing in parallel. Naturally, the annular step portion 18 is on the annular gap 19 side, and an iron plate thicker than the step is produced by a half punch process.

In the case of this electromagnetically driven valve, by providing the annular stepped portion 18, the electromagnetic driving force that acts on the plate-like plunger 17 at the time of excitation becomes larger than when it is not provided.

For example, in the embodiment of FIG. 2, the distance between the plate-like plunger 7 and the plate 5 is 1.2 mm and the plate thickness is 1.5 mm, and the plate-like plunger 1 7 and the plate 4 2 of FIG. 1.2 mm spacing, annular step Compared to the case where the step height of section 18 is 0.6 mm and the plate thickness is 1.5 mm, and the case where the step height of annular step portion 18 is 0.9 mm and the plate thickness is 1.5 mm. Then, the electromagnetic driving force is about 2 to 3 to 4 with the same energization voltage value.

Increasing the level difference of the annular stepped portion 1 8 causes magnetic saturation at the boundary of the annular stepped portion 1 8, and the electromagnetic driving force does not become too large even when the energization voltage is increased, and is saturated nonlinearly. In order to show the trend, the thickness of the plate-shaped plunger 1 7 must be greater than the step plus 0.6 mm. Increasing the level of the step further increases the initial electromagnetic driving force, but the electromagnetic driving force at the middle of the displacement or at the final displacement position is different. Then select the size of the step.

In this embodiment, as an example, the step of the stepped portion 18 is preferably about 0.6 to 0.9 mm. The interval between the parallel portions of the plate-shaped plunger 1 7 and the plate 4 2 is, for example, around 1.0 to 1.3 mm, and the thickness of the plate-shaped blanker 1 7 is, for example, 1.2 to 1.6 mm. The width of the annular gap 19 is, for example, about 3.0 to 4.0 mm. Of course, in some cases, sizes outside the above range are also applicable in this embodiment.

Third embodiment

FIG. 4 shows a third embodiment of the electromagnetically driven valve of the present invention. Aside from height, when slimming the shape, there are fluid inlets 4 6, 4 7 and 4 8 provided in the casings 4 4 and 4 5 constituting the valve housing 4 3. The thickness of the is substantially increased. Restricting the direction without fluid inlets 4 6, 4 7 and 4 8 is the width required in the vicinity of the valve section 4 9 of the piston rod, but there are few restrictions. Assuming the restrictions of the housings 4 4 and 4 5 of the valve housing 4 3, the width of the U-shaped part for attaching the yoke 5 1 of the magnetic plate of the solenoid housing 50 is set to a width other than the U-shaped part. By attaching to the housing 4 4 larger than the width of the part, the space between the yoke 5 1 and the cylindrical iron core 2 8 can be increased as much as possible, reducing the magnetic leakage of the entire solenoid housing 50 and reducing the overall magnetic leakage. The magnetic field near the gap 52 can be made relatively strong. As a result, a large electromagnetic driving force can be obtained.

If there is an annular stepped portion 5 8 on the plate-like plunger 53, the stepped portion 5 8 force during excitation is increased by the force in the direction orthogonal to the axis of the piston rod 2 5 as it approaches the annular gap 52. Arise. If it is a thin extension 26, there is a danger that it will be bent and a part of the annular step 5 8 and a part of the annular gap 52 will contact. This can be prevented by making the diameter of the end portion 27 of the extension 2 6 of the piston rod 25 larger than the diameter of the extension 26 and approximating the inner diameter of the cylindrical iron core. Further, a notch may be formed in the outer peripheral portion of the end portion 27 of the extension portion 26 so that an air flow is easily generated. It is possible to play the role of the center positioning of the piston rod 25 with the end portion 27 with the increased diameter, but considering long-term sliding wear, it is appropriate to perform sliding and center positioning with resin. It is.

To attach the solenoid housing 5 0 to the housing 4 4 of the valve housing 4 3, two L-shaped fixing parts 5 4 and 5 5 are provided in parallel and opposite from the housing 4 4. The L-shaped fixing portions 5 4 and 5 5 may be fixed to the screw holes provided in the yoke 51 with screws 5 6 and 5 7. In this embodiment, as an example, the level difference of the level difference portion 58 is, for example, in the range of 0.6 to 0.9 mm. The interval between the parallel portions of the plate-like plunger 53 and the plate 59 is, for example, around 1.0 to 1.2 mm, and the thickness of the plate-like plunger 53 is, for example, 1.2 to 1.6. The width of the annular gap 52 is 2.5 to 3.0. It is around mm. Of course, in some cases, sizes outside the above range are also applicable in this embodiment.

Claims

1. Cover the outer periphery and bottom of a cylindrical coil with a first magnetic plate, and connect the cylindrical second magnetic member to the center of the cylindrical coil continuously with the first magnetic plate. A circular hole in the center of the third magnetic plate arranged on the inside and continuously arranged from the end opposite to the bottom of the first magnetic plate is requested.

An annular gap having an outer diameter of the cylindrical second magnetic body as an inner diameter is formed on the outer diameter, and the circular fourth magnetic body plate is movable so as to face the annular gap. An electromagnetically driven valve characterized in that a solenoid housing is disposed and the fourth magnetic plate having a circular shape is fixed to an end of an extension portion of the piston rod. Surrounding

2. An electromagnetically driven valve is constituted by the piston rod having annular rubber in the upper and lower valve portions, the spring for adding a load to the piston rod, and the valve housing having three fluid inlets and outlets. Item 1. The electromagnetically driven valve according to item 1.

3. An annular step portion having an outer diameter smaller than the outer diameter of the annular gap and an inner diameter larger than the inner diameter of the annular gap is formed on the circular magnetic plate. The electromagnetically driven valve according to claim 1, wherein the electromagnetically driven valve is formed on a gap side.

4. A non-circular protrusion is provided at the end of the extension of the piston rod, and a non-circular hole formed in the center of the disk-shaped fourth magnetic plate is formed in the protrusion. The electromagnetically driven valve according to any one of claims 1 to 3, wherein the electromagnetically driven valve is fitted and supported.

5. A circular projecting portion larger than the outer diameter of the piston rod is slidably provided on the inner wall surface of the hollow portion of the casing of the valve housing at a position between the piston rod and the extension portion. The electromagnetically driven valve according to claim 1 or 2, characterized in that

6. The outer diameter of the piston rod near the end of the extension has an increased size approximating the inner diameter of the cylindrical second magnetic body. 2. The electromagnetically driven valve according to 2.

7. The first magnetic plate of the solenoid housing is formed in a U shape, the width in the direction having the U shape surface is larger than the width in the direction not having the U shape surface, and the valve housing The electromagnetically driven valve according to claim 1 or 2, wherein an L-shaped fixed portion is provided in parallel to the housing of the housing and the solenoid housing is fixed.