JP2012104591A - Electromagnetic solenoid device for controlling valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic solenoid device 1 for controlling a valve, that eliminates a risk of oil leakage from a cylindrical yoke 7, spoils no dimensional accuracy between a thin and short cylinder part 7c and a cylindrical yoke 7, and contributes to productivity by cutting down the number of components to reduce manufacturing man-hours.SOLUTION: Since the thin and short cylindrical part 7c is integrally formed with the cylindrical yoke 7, no thermal strain is caused in the thin and short cylindrical part 7c and the cylindrical yoke 7, their dimensional accuracy and fitting accuracy are not deteriorated, besides, they are advantageous in terms of cost because no processing is required after cutting, and excellent magnetic attraction characteristics can be obtained. A cylindrical collar 8 made of a nonmagnetic material is fitted into the peripheral part 7d of the thin and short cylindrical part 7c to reinforce the thin and short cylindrical part 7c, and pressure resistance and load resistance with respect to the circumferential direction and axial direction of the cylindrical yoke 7 can be thereby obtained.

Description

  The present invention relates to an electromagnetic solenoid device for valve control that drives a valve body of a vehicle-mounted component, and more particularly to an electromagnetic solenoid device for valve control that adjusts the amount of movement of a plunger by the amount of current supplied to a coil body.

For example, a semi-active damper built into a suspension for a vehicle has a stable and comfortable ride by suppressing the thrust vibration from the road surface by finely adjusting the damping force of the hydraulic damper with an electromagnetically controlled valve. The vehicle is driving.
Examples of the electromagnetic control type valve include a solenoid of a solenoid valve (for example, see Patent Document 1) and an electromagnetic proportional control valve (for example, see Patent Document 2).
In patent document 1, as shown to Fig.4 (a), the coil 50 is provided in the outer peripheral part, The stator core 51 which accommodated the plunger 52 in the inside so that sliding is possible is provided.
The stator core 51 has a magnetic body 51a, a nonmagnetic body 51b, and a magnetic body 51c arranged in this order along the axial direction.

  Since the non-magnetic body 51b is fixed by welding means so as to be sandwiched between the magnetic bodies 51a and 51c, the non-magnetic body 51b acts as magnetic shielding means when the coil 50 is energized, and a plunger for the stator core 51 The magnetic attractive force of 52 is increased to maintain excellent magnetic attractive characteristics.

  In patent document 2, as shown in FIG.4 (b), the cylindrical fixed iron core 54 which was provided in the electromagnetic coil 53 and accommodated the movable iron core 55 as a plunger inside is provided. A thin portion 54 a is formed by cutting the outer peripheral portion of the cylindrical fixed iron core 54. A filler 56 made of a non-magnetic material is fixed to the outer peripheral portion of the thin portion 54a. When the electromagnetic coil 53 is energized, the filler 56 functions as a magnetic shielding means, and the magnetic attractive force of the movable iron core 55 with respect to the distal end portion 54b of the cylindrical fixed iron core 54 is increased.

JP 2003-269638 A Japanese Utility Model Publication No. 57-164371

In patent document 1, since the nonmagnetic body 51b is joined to the magnetic bodies 51a and 51c by various welding, a welding process is required. In post-welding, it is necessary to increase the cylindricity by cutting the inner surfaces of the non-magnetic body 51b and the magnetic bodies 51a and 51c together with the inner surface of the stator core 51 to maintain concentricity with the plunger 52. Increased and disadvantageous in cost.
When the nonmagnetic body 51b is joined or post-processed, there is a possibility that oil leakage may occur from the stator core 51 due to poor joining between the nonmagnetic body 51b and the magnetic bodies 51a and 51c.
In addition, when joining the non-magnetic body 51b and the magnetic bodies 51a and 51c by welding or brazing, the dimensional accuracy between the non-magnetic body 51b and the magnetic bodies 51a and 51c is impaired due to local thermal distortion. There is a possibility that the attaching accuracy may be lowered.

In Patent Document 2, a process of fixing the filler 56 to the thin-walled portion 54a is necessary, and a grinding / polishing process for aligning the filler 56 with a uniform thickness is also required, which increases the number of manufacturing steps.
Since the thin wall portion 54a forms the bottom of the circumferential groove having a trapezoidal cross section, the reinforcing action of the thin wall portion 54a is impaired due to poor fixing of the filler 56, and oil leakage from the cylindrical fixed iron core 54 occurs. May occur.
As for the filler 56 and the cylindrical fixed iron core 54, as in Patent Document 1, thermal distortion occurs at the boundary between the two, the cylindricity decreases, and the concentricity with the movable iron core 55 is lost. There is a possibility that the accuracy is lowered and the assembling accuracy is impaired.

  The present invention has been made in view of the above circumstances, and its purpose is to provide a thin short tube portion and maintain excellent magnetic attraction characteristics, while ensuring the required strength in the thin short tube portion and preventing oil leakage. There is no danger, and thermal distortion does not impair the dimensional accuracy of the thin short tube section and the cylindrical yoke, the assembly accuracy does not decrease, and the number of parts is reduced to improve the productivity. It is to provide an electromagnetic solenoid device for valve control that contributes to the above.

(About claim 1)
The coil body is formed in a cylindrical shape by winding a conductive wire around a spool. The one-end-closed cylindrical yoke is made of a magnetic material, and is arranged concentrically inside the coil body, and has a closed portion at one end and an opening at the other end.
The thin short cylindrical portion is integrally formed with the opening of the cylindrical yoke, and has a thickness smaller than the thickness of the cylindrical yoke as a magnetic saturation portion. The cylindrical collar made of non-magnetic material is fitted into the outer peripheral portion of the thin short tube portion to reinforce the thin short tube portion. The large connecting flange tube portion is integrally formed with the thin short tube portion and is larger in diameter than the cylindrical yoke and the thin short tube portion.
The core stator is connected to the central opening of the connecting flange tube portion, and the outer peripheral end portion faces the step end portion between the thin short tube portion and the cylindrical yoke via a gap.
The plunger is disposed so as to be reciprocally movable in the axial direction within the cylindrical yoke, has a guide passage formed through in the axial direction, and is slidable toward the core stator according to the amount of current supplied to the coil body. Yes. When the connecting flange cylinder is connected to the vehicle drive body, the balance of the hydraulic oil pressure of the drive oil received from the drive body and the magnetic attraction force of the plunger by the coil body causes the valve body connected to the tip of the plunger. The amount of oil circulating through the drive body is controlled by adjusting the opening.

In the above configuration, the stepped end with the cylindrical yoke faces the outer peripheral edge of the core stator via a gap, so that the magnetic flux of the coil body hardly flows through the thin short cylindrical portion.
As a result, most of the magnetic flux generated by the coil body flows from the cylindrical yoke to the plunger, and the magnetic attractive force of the plunger with respect to the core stator can be increased to ensure excellent magnetic attractive characteristics.

The non-magnetic cylindrical collar is fitted on the outer periphery of the thin short tube to reinforce the thin short tube, ensuring the pressure resistance and load resistance in the circumferential and axial directions of the thin short tube can do.
For this reason, even if the internal pressure of the cylindrical yoke is increased by the drive oil, the thin short cylinder part will not easily be deformed or broken, and the axial pressure is applied to the thin short cylinder part by inserting related parts during assembly. Even if this works, the thin short tube portion is not inadvertently deformed or crushed, and there is no possibility of oil leakage from the cylindrical yoke.

During assembly, thermal distortion does not occur in the thin short tube portion and the cylindrical yoke, the dimensional accuracy between the thin short tube portion and the cylindrical yoke does not decrease, and the assembly accuracy does not decrease. This eliminates the need for post-processing such as cutting, which is advantageous in terms of cost.
In addition, since the connecting flange cylinder, the thin short cylinder and the cylindrical yoke are integrally formed, the number of parts can be reduced and the number of manufacturing steps can be reduced compared to the case where they are formed separately. Contributes to improved productivity.

  The thin and short cylindrical portion works to increase the magnetic attractive force of the plunger with respect to the core stator at the opening of the cylindrical yoke. Therefore, by changing the inner surface shape of the core stator and the tip shape of the plunger in various ways, Various magnetic attraction characteristics can be easily set by changing the magnetic flux distribution.

(About claim 2)
Since the driving body is a hydraulic damper for the suspension for the vehicle, it is possible to satisfactorily attenuate the vibration caused by the road surface condition and contribute to comfortable and stable running of the vehicle.

(Claim 3)
A bush made of a magnetic material mainly composed of metal such as iron is disposed in an annular gap between the outer peripheral portion of the cylindrical yoke and the inner peripheral surface of the coil body.
Since the cylindrical collar is fitted into the outer peripheral portion of the thin short cylindrical portion, an annular gap is formed between the outer peripheral portion of the cylindrical yoke and the inner peripheral surface of the coil body. The cross-sectional area of increases substantially. As a result, the magnetic flux from the coil body flows to the plunger via the bush and the cylindrical yoke, and the magnetic attraction force of the plunger with respect to the core stator is prevented from decreasing.

(About claim 4)
The connecting flange cylindrical portion is integrally formed so that the outer cylindrical portion that fits the outer peripheral portion of the coil body is concentric with the cylindrical yoke.
As a result, the four parts of the outer cylindrical part, the connecting flange cylindrical part, the thin short cylindrical part, and the cylindrical yoke are integrated. Can be

(Claim 5)
At one end of the coil body, a plate penetrating the cylindrical yoke is attached so as to be perpendicular to the bush. The bush is integrally formed with its one end opening in contact with the plate.
In this case, since the bush is integrated with the plate, the number of parts is reduced, which contributes to a reduction in assembly man-hours and contributes to an improvement in productivity.

(About claim 6)
Since the closed part of the cylindrical yoke is bent into a semispherical shape that protrudes to the outside, even if the internal pressure of the cylindrical yoke is increased by the drive oil, the tensile stress that the closed part receives in the circumferential direction is kept small. Can do.

(Example 1) which is a longitudinal cross-sectional view of the solenoid solenoid apparatus for valve control. It is a magnetic attraction force characteristic view showing the relationship between the stroke of the plunger and the magnetic attraction force. (Example 2) which is a longitudinal cross-sectional view of the solenoid solenoid apparatus for valve control. (A) is a longitudinal cross-sectional view which shows the solenoid of the conventional solenoid valve, (b) is a longitudinal cross-sectional view which shows the principal part of the conventional electromagnetic proportional control valve.

  Embodiments of the solenoid solenoid device for valve control according to the present invention will be described with reference to the drawings.

[Configuration of Example 1]
1 and 2 show Embodiment 1 of the present invention. An electromagnetic solenoid device 1 for valve control shown in FIG. 1 is generally used as a driving body for a vehicle control valve that opens and closes various valves. In the first embodiment, a hydraulic damper (not shown) for a vehicle suspension is used. Has been applied.

The solenoid solenoid device for valve control 1 includes a coil body 3 formed in a cylindrical shape by winding a conductive wire (copper wire) around a spool 2. The outer surface portion of the coil body 3 is encapsulated by molding with a resin, and a socket portion 5 having a pair of terminals 4 (only one shown) is extended and formed.
A plate 6 having a through hole 6 a concentric with the coil body 3 is attached to one end of the coil body 3.

  Inside the coil body 3, a one-end-closed cylindrical yoke 7 formed of a magnetic material is disposed so as to be concentric. One end of the cylindrical yoke 7 has a closed portion 7a, and the other end has an opening 7b. The blocking part 7 a forms a flat surface, and the outer peripheral edge of the blocking part 7 a is attached in a state of being fitted in the through hole 6 a of the plate 6.

A thin short cylindrical portion 7c having a thickness smaller than the thickness of the cylindrical yoke 7 is integrally formed in the opening 7b of the cylindrical yoke 7 so as to extend concentrically with the opening 7b along the axial direction. .
Since the thin short tube portion 7c is formed by removing the inner peripheral surface of the opening 7b, the outer peripheral portion 7d of the thin short tube portion 7c is flush with the outer peripheral portion 7e of the cylindrical yoke 7. .
Since the thin short tube portion 7c functions as a magnetic saturation portion (magnetic shielding means), the thickness of the thin short tube portion 7c is large enough to substantially block the magnetic flux flowing from the coil body 3 to the cylindrical yoke 7. Is set.
Note that the outer peripheral portion 7d of the thin short tube portion 7c and the outer peripheral portion 7e of the cylindrical yoke 7 are not limited to the same plane, but a step where the outer peripheral portion 7e has a small diameter at the boundary between the outer peripheral portions 7d and 7e. Part may occur.

  A reinforcing cylindrical collar 8 is fitted into the outer peripheral portion 7d of the thin short cylindrical portion 7c by press-fitting from the entire length of the outer peripheral portion 7d to a part of the cylindrical yoke 7. The cylindrical collar 8 is made of a nonmagnetic material and is disposed between the outer peripheral portion 7d of the thin short cylindrical portion 7c and the inner peripheral surface 3a of the coil body 3.

  Since the cylindrical collar 8 is fitted into the outer peripheral portion 7d of the thin short cylindrical portion 7c, an annular gap is generated between the outer peripheral portion 7e of the cylindrical yoke 7 and the inner peripheral surface 3a of the coil body 3. In this case, the cross-sectional area of the cylindrical yoke 7 is substantially increased by fitting the magnetic bush 20 into the outer peripheral portion 7e of the cylindrical yoke 7 and disposing the bush 20 in the annular gap.

  The connecting flange cylindrical portion 9 existing outside the coil body 3 has a U-shaped cross section, and is integrally formed so as to be concentric with the tip of the thin short tube portion 7c. The cylindrical yoke 7 and the thin short tube The diameter is set larger than that of the portion 7c. The connecting flange cylindrical portion 9 is integrally formed with an outer cylindrical portion 7 g that fits the outer peripheral portion of the coil body 3 so as to be concentric with the cylindrical yoke 7.

The core stator 10 is provided in the central opening 9a of the connecting flange tube portion 9 so that the outer peripheral edge portion 10a faces the step end portion 7f between the thin short tube portion 7c and the cylindrical yoke 7 with a gap G therebetween. It is arranged.
A columnar plunger 11 is disposed in the cylindrical yoke 7 so as to be capable of reciprocating in the axial direction, and slides with the inner peripheral surface of the cylindrical yoke 7 as a sliding guide portion. The plunger 11 penetrates the guide path 11a in the axial direction, and is slidable in a direction in which the plunger 11 approaches and separates from the core stator 10 according to the amount of current supplied to the coil body 3.
The plunger 11 is formed with an oil return path 11b parallel to the guide path 11a in a penetrating state.

  The hollow plunger shaft 12 is provided so as to be able to interlock with the plunger 11 through the through hole 10 b formed in the core stator 10. A gap provided between the plunger shaft 12 and the inner peripheral surface of the through hole 10 b is defined as an oil drainage passage 14.

  The plunger shaft 12 has a hollow interior as an introduction path 12a communicating with the guide path 11a, and is always urged toward the plunger 11 by a compression coil spring (not shown) as an urging member. Thereby, the communication state of the introduction path 12a and the guide path 11a is always maintained. A retaining E-ring 15 is fitted into the rear end portion of the plunger shaft 12.

  The rear end surface portion of the core stator 10 has an annular rising side 10c formed by, for example, cutting, and is positioned in an opposed state to the outer peripheral portion of the distal end of the plunger 11 that is close to the core stator 10 by a magnetic attractive force. .

When the connecting flange cylinder portion 9 is connected to the hydraulic damper of the vehicle suspension via the joint pipe portion 16, the amount of current supplied to the coil body 3 is adjusted by computer processing according to the running state of the vehicle.
Accordingly, the opening degree of the valve body (not shown) connected to the tip of the plunger 11 is adjusted by the balanced relationship between the hydraulic pressure of the driving oil received from the hydraulic damper and the magnetic attractive force of the plunger 11 by the coil body 3. Thus, the amount of oil circulating through the hydraulic damper is controlled.
In this process, the damping amount and timing of the hydraulic damper are adjusted by finely adjusting the damping force of the hydraulic damper, and the thrust vibration from the road surface is suppressed to promote a stable and comfortable running of the vehicle. .

[Effect of Example 1]
According to the above configuration, the stepped end portion 7f with the cylindrical yoke 7 is arranged to face the outer peripheral edge portion 10a of the core stator 10 via the gap G, so that the magnetic flux of the coil body 3 hardly flows through the thin short tube portion 7c. Become.
As a result, most of the magnetic flux generated by the coil body 3 flows from the cylindrical yoke 7 to the plunger 11, increasing the magnetic attractive force of the plunger 11 with respect to the core stator 10, and ensuring excellent magnetic attractive characteristics.

Incidentally, FIG. 2 shows the relationship between the stroke of the plunger 11 and the magnetic attractive force. The magnetic attractive characteristic is shown in FIG. 2, and the thin portion and the cylindrical yoke 7 of Patent Document 2 formed on the inner peripheral surface side of the cylindrical fixed iron core. The thin short cylinder part 7c of the present Example 1 formed in the outer peripheral surface side is compared. The former is indicated by a broken line with white dots as “inner arrangement of the thin short cylinder part”, and the latter is indicated by solid lines with black dots as “outer arrangement of the thin short cylinder part”.
As can be seen from a comparison between the solid line and the broken line in FIG. 2, in the “outside arrangement of the thin short tube portion” of the first embodiment, the magnetic shielding function of the thin short tube portion 7 c works effectively. Compared with the “inside arrangement of the thin short tube portion”, an excellent magnetic attractive force characteristic is obtained in which the magnetic attractive force increases as the plunger 11 approaches the attractive side of the core stator 10.

The non-magnetic cylindrical collar 8 is fitted into the outer peripheral portion 7d of the thin short cylindrical portion 7c and strongly reinforces the thin short cylindrical portion 7c. Load resistance can be ensured.
For this reason, even if the internal pressure of the cylindrical yoke 7 is increased by the drive oil, the thin short tube portion 7c is not easily deformed or broken, and the thin short tube portion is inserted by inserting related parts during assembly. Even if axial pressure is applied to 7c, the thin short cylindrical portion 7c is not inadvertently deformed or crushed, and there is no possibility of oil leakage from the cylindrical yoke 7.

  Since the thin short cylindrical portion 7c is formed integrally with the cylindrical yoke 7, thermal thinning does not occur in the thin short cylindrical portion 7c and the cylindrical yoke 7 due to the temperature rise, and the thin short cylindrical portion 7c and the cylindrical yoke 7 are formed. Therefore, the dimensional accuracy is not lowered, and the assembly accuracy is not lowered. In addition, there is no need to perform post-processing such as cutting, which is advantageous in terms of cost.

  Further, since the connecting flange cylindrical portion 9, the thin short cylindrical portion 7c and the cylindrical yoke 7 are integrally formed, the number of parts can be reduced and the number of manufacturing steps can be reduced as compared with the case where they are formed separately. Decreases and contributes to productivity improvement.

  Since the thin short cylindrical portion 7c works to increase the magnetic attractive force of the plunger 11 with respect to the core stator 10 at the opening 7b of the cylindrical yoke 7, various shapes of the inner surface of the core stator 10 and the distal end shape of the plunger 11 can be obtained. By changing the magnetic flux distribution by the coil body 3, various variations of magnetic attraction characteristics can be easily set.

  Since the magnetic bush 20 is fitted on the outer peripheral portion 7e of the cylindrical yoke 7, the bush 20 is arranged in the annular gap formed between the cylindrical yoke 7 and the coil body 3, and the cylindrical yoke is arranged. The sectional area of 7 is substantially increased. Thereby, the magnetic flux from the coil body 3 flows directly to the plunger 11 via the bush 20 and the cylindrical yoke 7, thereby preventing the magnetic attractive force of the plunger 11 with respect to the core stator 10 from being reduced.

  The connecting flange cylindrical portion 9 is integrally formed with an outer cylindrical portion 7 g that fits the outer peripheral portion of the coil body 3 so as to be concentric with the cylindrical yoke 7. As a result, the four members of the outer cylindrical portion 7g, the connecting flange cylindrical portion 9, the thin short cylindrical portion 7c, and the cylindrical yoke 7 are integrated, and the attachment state of the four members to the coil body 3 is strengthened and the whole is made. Can be hardened.

[Example 2]
FIG. 3 shows a second embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the closed portion 7a of the cylindrical yoke 7 has a hemispherical shape that is convex outward.
Thereby, even if the internal pressure of the cylindrical yoke 7 is increased by the drive oil, the tensile stress that the closing portion 7a receives in the circumferential direction can be kept small.

[Modification]
(A) The length dimension and thickness dimension of the thin short cylindrical portion 7c in the first embodiment may be changed as desired according to the use situation and the attachment target in consideration of the relationship with the size of the cylindrical yoke 7.
(B) Although the four members of the outer cylindrical portion 7g, the connecting flange cylindrical portion 9, the thin short cylindrical portion 7c, and the cylindrical yoke 7 are integrally formed, the outer cylindrical portion 7g is separated from the other three members. It may be.

(C) The reinforcing cylindrical collar 8 is attached to the outer peripheral part 7d of the thin-walled short cylinder part 7c by press fitting, but it may be attached by a technique such as shrink fitting or interference fitting.
(D) The bush 20 may be formed integrally with the plate 6 such that the one end opening 20 a is concentrically contacted with the peripheral edge of the through hole 6 a of the plate 6. This reduces the number of parts, contributes to a reduction in assembly man-hours, and contributes to an improvement in productivity.

  In the present invention, since the stepped end portion with the cylindrical yoke faces the outer peripheral end portion of the core stator via a gap, the magnetic flux of the coil body hardly flows through the thin short cylindrical portion, and excellent magnetic attraction characteristics are obtained. It is done. The cylindrical collar made of non-magnetic material is fitted into the outer peripheral portion of the thin short tube portion and strongly reinforces the thin short tube portion, so that the pressure resistance and load resistance in the circumferential direction and the axial direction of the cylindrical yoke can be obtained. . From these excellent viewpoints, the demand for the vehicle-related business will be stimulated, and it will be applicable to the machine industry through parts distribution.

DESCRIPTION OF SYMBOLS 1 Electromagnetic solenoid device for valve control 2 Spool 3 Coil body 3a Inner peripheral surface of coil body 6 Plate 7 Cylindrical yoke 7a Closure part 7b Opening part 7c Thin short cylinder part (magnetic saturation part)
7d Outer peripheral part of thin-walled short cylinder part 7e Outer peripheral part of cylindrical yoke 7f Step end part 7g Outer cylindrical part 8 Cylindrical collar 9 Flange cylindrical part for connection 10 Core stator 10a Outer peripheral edge part of core stator 11 Plunger 11a Guide path 12 Plan Jar shaft 12a Introduction path 20 Bush 20a One end opening of bush G Gap of step end

Claims (6)

A coil body formed by winding a conductive wire around a spool into a cylindrical shape;
A cylindrical yoke that is concentrically arranged inside the coil body, has a closed portion at one end, and is formed of a magnetic material so as to have an opening at the other end;
A thin short cylindrical portion integrally formed in the opening of the cylindrical yoke and having a thickness smaller than the thickness of the cylindrical yoke as a magnetic saturation portion;
A cylindrical collar made of a non-magnetic material that is fitted into the outer peripheral portion of the thin short tube portion and reinforces the thin short tube portion;
A connection flange cylinder part that is integrally formed with the thin short cylinder part, and has a diameter larger than that of the cylindrical yoke and the thin short cylinder part,
A core stator connected to a central opening of the connecting flange tube portion and provided with an outer peripheral end portion facing a step end portion of the thin short tube portion and the cylindrical yoke with a gap;
A plunger disposed in the cylindrical yoke so as to be capable of reciprocating in the axial direction, having a guide passage formed through in the axial direction, and slidable toward the core stator side in accordance with the amount of current supplied to the coil body; With
When the connecting flange cylinder is connected to the vehicle drive body, the balance of the hydraulic oil pressure of the drive oil received from the drive body and the magnetic attraction force of the plunger by the coil body causes the valve body connected to the tip of the plunger. An electromagnetic solenoid device for valve control, wherein the amount of oil circulating through the drive body is controlled by adjusting the opening degree.   2. The solenoid solenoid device for valve control according to claim 1, wherein the driving body is a hydraulic damper of a vehicle suspension.   The magnetic bush mainly composed of metal such as iron is disposed in an annular gap between the outer peripheral portion of the cylindrical yoke and the inner peripheral surface of the coil body. Electromagnetic solenoid device for valve control.   2. The connecting flange cylindrical portion is integrally formed with an outer cylindrical portion that fits an outer peripheral portion of the coil body so as to be concentric with the cylindrical yoke. Electromagnetic solenoid device for valve control.   A plate penetrating the cylindrical yoke is attached to one end of the coil body so as to be perpendicular to the bush, and the bush is in a state where its one end opening is in contact with the plate. 4. The electromagnetic solenoid device for valve control according to claim 3, wherein the solenoid solenoid device is integrally formed.   2. The solenoid solenoid device for valve control according to claim 1, wherein the closing portion of the cylindrical yoke is bent in a hemispherical shape protruding outward.

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