JPH10318409A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid valve having a flat characteristic giving large attractive force to a moving piece and no change of the attractive force even by changing a distance between a core and the moving piece. SOLUTION: A valve comprises a nearly cylindrical coil assembly 2 fixed in a cylindrical case 1, core 3 fixed to a cylindrical inner part of this coil assembly 2, moving piece 10 arranged on a shaft end side of this core 3 and capable of approaching/separating to/from the core 3, and a valve element 31 linked to this moving piece 10. Between the moving piece 10 and the core 3, an inside magnetic leakage part 15 provided with an independent surface 18 without changing a relative distance according to movement of the moving piece 10 is formed. Between the moving piece 10 and the case 1, an outside magnetic leakage part 20 provided with a correlated surface 22 changing a relative distance according to the movement of the moving piece 10 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve, and more particularly to a solenoid valve which can be applied to a pressure regulating valve for obtaining a control pressure of an automatic transmission for an automobile.

[0002]

2. Description of the Related Art A solenoid valve of this type is disclosed in
The one disclosed in -180390 is known.
The solenoid valve described in the above publication includes a cylindrical case, a cylindrical coil assembly fixed in the case, a core fixed in a cylindrical inside of the coil assembly, and a shaft of the core. On the end side, a movable element that is arranged to be able to approach and separate from the core and forms a magnetic leakage portion with the core, and a valve body that is connected to the movable element, and has an electromagnetic force of the coil assembly The movement of the mover is controlled by controlling the energization of the coil, and the valve element connected to the mover is controlled.

In the conventional solenoid valve, a magnetic leakage portion for determining the magnitude of the attraction force of the mover by the electromagnetic coil is formed at one location between the core and the mover. If it is intended to obtain the size, the core and the mover must be enlarged, and the solenoid valve becomes large.

On the other hand, in Japanese Patent Application Laid-Open No. 5-52274, a mover is formed in a cylindrical shape, and an inner peripheral side of the mover is provided with a tapered surface adapted to a taper surface on an outer peripheral side of a core. By forming an outer annular projection having a tapered surface that fits the outer peripheral taper surface of the yoke connected to the core on the outer peripheral side, the outer peripheral taper surface of the core and the inner annular projection are formed. The inner magnetic leakage portion is formed between the outer magnetic projection portion and the tapered surface of the yoke and the outer magnetic leakage portion is formed between the outer peripheral tapered surface of the yoke and the tapered surface of the outer annular projection, so that a large attractive force can be obtained. Solenoid valves have been proposed.

[0005]

However, in the above-mentioned prior art, although the magnetic attraction to the mover can be obtained by forming the magnetic leakage portions at the inner side and the outer side, each magnetic leakage portion can be obtained. Are formed between the tapered surfaces whose relative distances change with the movement of the mover, so that the attracting force increases as the mover approaches the core.

That is, the tapered surface of the inner annular projection is planarly approached and separated from the outer peripheral tapered surface of the core, and the tapered surface of the outer annular projection is planarly approached and spaced from the outer tapered surface of the yoke. Since the cores are separated from each other, a plane whose relative distance changes with the movement of the core is formed opposite to each other between the core and the mover, and a magnetic leakage portion is formed between the planes. Therefore, as the mover approaches the core, the attraction force to the mover increases.

[0007] The above characteristic is that when the solenoid valve controls ON and OFF of the valve body by energizing and stopping energization of the electromagnetic coil, no particular problem occurs. However, this electromagnetic valve is used as a pressure control valve. Then, the suction force is changed according to the magnitude of the current (or voltage) applied to the electromagnetic coil,
It is not preferable to control the pressure of the fluid in accordance with the suction force.

That is, the characteristic that the attraction force changes as the mover approaches the core is that when the valve element connected to the mover moves and controls the pressure, the current (or voltage) applied to the electromagnetic coil is reduced. Even if the size is constant, the pressure characteristic changes depending on the stroke of the valve body, which is not preferable.

Therefore, the characteristic of the solenoid valve applicable to the pressure control valve is that it has a flat region where the suction force acting on the movable element does not change even if the relative distance between the core and the movable element changes. It is desired.

The present invention has been devised in view of the above-mentioned conventional circumstances, and can provide a large attraction force to the mover, and can move even if the distance between the core and the mover changes. An object of the present invention is to provide a solenoid valve having flat characteristics in which a suction force acting on a child does not change.

[0011]

SUMMARY OF THE INVENTION Therefore, the invention according to claim 1 is characterized in that a cylindrical case is fixed in the case,
A substantially cylindrical coil assembly having a bobbin and an electromagnetic coil wound on the bobbin, a core fixed inside a cylindrical portion of the coil assembly, and a core disposed on the shaft end side of the core. A movable element that can be moved toward and away from the movable element, a valve element connected to the movable element, and an independent surface formed between the movable element and the core, the relative distance not changing with the movement of the movable element. And an outer magnetic leakage portion formed between the mover and the case and having a correlation surface whose relative distance changes with the movement of the mover.

According to a second aspect of the present invention, in the configuration of the first aspect, a coil insertion portion in which a connection end of an electromagnetic coil is located is formed at one end of a bobbin of the coil assembly. An annular gap is formed between the coil insertion portion and the core, while the movable element is formed with an annular flange that enters the gap and forms an inner magnetic leakage portion. It is.

Further, the invention according to a third aspect is the configuration according to the second aspect of the invention, wherein the gap is formed by enlarging the inner diameter of the coil insertion portion.

According to a fourth aspect of the present invention, in the configuration of the third aspect, the inner diameter of the coil insertion portion is tapered so that the inner diameter gradually increases toward one end of the bobbin. It is configured to have a diameter.

According to a fifth aspect of the present invention, there is provided a substantially cylindrical coil assembly having a cylindrical case, a bobbin fixed in the case, and an electromagnetic coil wound around the bobbin. A core fixed within the cylindrical interior of the coil assembly, a movable element disposed on the axial end side of the core and capable of approaching and separating from the core, a valve connected to the movable element, An inner magnetic leakage portion formed between the armature and the core and having a correlation surface whose relative distance changes with the movement of the armature, and formed between the armature and the case, And an outer magnetic leakage portion having an independent surface whose relative distance does not change accordingly.

In such a configuration, when a current is supplied to the electromagnetic coil of the coil assembly, a magnetic field is generated in the electromagnetic coil. Thus, the magnetic field generated by the electromagnetic coil passes through the case, the outer magnetic leakage part, the mover, and the inner magnetic leakage part, reaches the core, and as a result, the mover is attracted to the core.

The movement of the mover toward the core is controlled by controlling the energization of the electromagnetic coil. Thereby, the movement of the valve body connected to the mover is controlled, and a predetermined control state, for example, a predetermined control pressure is obtained.

Also, since both magnetic force passing through the inner magnetic leakage portion and magnetic force passing through the outer magnetic leakage portion act on the mover, both magnetic forces are added to the mover. A large suction force will be given.

According to the first aspect of the present invention, the inner magnetic leakage portion is formed with an independent surface whose relative distance does not change with movement of the mover, while the outer magnetic leakage portion has The inner magnetic leakage portion and the outer magnetic leakage portion have characteristics of the added attractive force applied to the mover because the mover has a correlation surface whose relative distance changes with the movement of the mover. A characteristic having a flat region in which the suction force does not change even when the relative distance between the core and the core (or the case) changes.

That is, in the inner magnetic leakage portion formed by an independent surface whose relative distance does not change with the movement of the mover,
As the mover approaches the core, the attracting force on the mover shows a characteristic of decreasing (proportional characteristic), while the outer magnetic leakage portion formed by a correlation surface in which the relative distance changes as the mover moves, As the mover approaches the case, it exhibits a characteristic (inverse proportional characteristic) in which the suction force on the mover increases.

Since the inner magnetic leakage portion has an independent surface and the outer magnetic leakage portion has a correlation surface, the solenoid valve has both a proportional characteristic and an inverse proportional characteristic added as an attractive force characteristic to the mover. Characteristics. For this reason, the characteristic of the added attractive force given to the mover at the inner magnetic leakage part and the outer magnetic leakage part is that the attractive force does not change even if the relative distance between the mover and the core (or case) changes. A characteristic having a flat region can be obtained.

Therefore, a large suction force can be applied to the movable element, and the flat element has a flat characteristic in which the attractive force acting on the movable element does not change even if the distance between the core and the movable element changes. A solenoid valve is obtained.

According to the second aspect of the present invention, when the mover moves and approaches the core, an annular flange formed on the mover is formed between the coil insertion portion of the bobbin and the core. Since the inner side magnetic leakage portion is formed by entering into the gap formed therebetween, the size of the solenoid valve can be reduced.

That is, the annular flange of the mover is
Since the coil enters the gap, the end of the core does not greatly protrude from the end face of the coil assembly, and the solenoid valve does not become longer in the axial direction.

In particular, the coil insertion portion of the bobbin is
Only the connection end of the electromagnetic coil is located, and even if a gap is formed on the inner peripheral side, generation of magnetic force by the electromagnetic coil does not have a particularly bad influence.

Therefore, the axial dimension can be reduced,
An electromagnetic valve that can be reduced in size can be obtained.

According to the third and fourth aspects of the present invention, since the diameter of the core is not reduced,
The area of the magnetic path of the inner magnetic leakage portion formed between the core and the annular flange of the mover can be increased.

According to the fifth aspect of the present invention, the inner magnetic leakage portion is formed with a correlation surface whose relative distance changes with movement of the mover, while the outer magnetic leakage portion is movable. Since the inner magnetic leakage portion and the outer magnetic leakage portion are formed with independent surfaces whose relative distance does not change with the movement of the armature, the characteristics of the added attractive force given to the mover at the inner magnetic leakage portion and the outer magnetic leakage portion are different from those of the armature. A characteristic having a flat region in which the suction force does not change even when the relative distance to the core (or the case) changes is obtained.

That is, in the inner magnetic leakage portion formed by the correlation surface in which the relative distance changes with the movement of the mover, the characteristic (inversely proportional) that the attracting force to the mover increases as the mover approaches the core. On the other hand, in the outer magnetic leakage portion formed by an independent surface whose relative distance does not change with the movement of the mover, as the mover approaches the case, the attraction force on the mover decreases (proportionality). Characteristics).

Since the inner magnetic leakage portion has a correlation surface and the outer magnetic leakage portion has an independent surface, the solenoid valve has both an inverse proportional characteristic and a proportional characteristic added as an attractive force characteristic to the mover. Characteristics. For this reason, the characteristic of the added attractive force given to the mover at the inner magnetic leakage part and the outer magnetic leakage part is that the attractive force does not change even if the relative distance between the mover and the core (or case) changes. A characteristic having a flat region can be obtained.

Therefore, a large suction force can be applied to the movable element, and the flat element has a flat characteristic in which the attractive force acting on the movable element does not change even if the distance between the core and the movable element changes. A solenoid valve is obtained.

[0032]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a solenoid valve according to an embodiment of the present invention, in which the upper half shows a state where power is not supplied to the electromagnetic coil, and the lower half shows a state where power is supplied to the electromagnetic coil. FIG. 2 is a diagram showing the attraction force characteristics of the mover by the electromagnetic coil of the solenoid valve of the present invention.

In FIG. 1, reference numeral 1 denotes a cylindrical case having one end sealed, and 2 denotes a substantially cylindrical coil assembly fixed in the case 1. Numeral 3 is a core fixed inside the cylindrical shape of the coil assembly 2, and this core 3 is formed integrally with the case 1 in this embodiment.

The coil assembly 2 includes a bobbin 4 and an electromagnetic coil 5 wound around the bobbin 4. A coil insertion portion 6 is formed at one end of the bobbin 4. A connection end (not shown) of the electromagnetic coil 5 is located in the coil insertion portion 6.
Is connected to a control device and a power supply (not shown).

The coil insertion part 6 formed on the bobbin 4
An annular gap 8 is formed between the core 3 and the core 3.
The gap 8 is formed by enlarging the inner diameter of the coil insertion portion 6, and the inner diameter is tapered so that the inner diameter gradually increases toward one end of the bobbin 4. .

The coil assembly 2 is integrated with the pin terminal 7 with its outer peripheral side covered by a cover 9.
In this state, it is housed and fixed in the case 1.

Reference numeral 10 denotes a substantially flat movable element disposed on the shaft end side of the core 3. The movable element 10 has a through hole 11 formed at a substantially central position. The mover 10 has a support projection 1 in which a through hole 11 at a substantially central position is formed at the tip of the core 3.
3 is fitted via a bearing 14 so that it is slidable in the axial direction and can approach and separate from the core 3.

The movable element 10 has an end face on the core 3 side,
An annular flange 16 is formed which enters the gap 8 and forms the inner magnetic leakage portion 15. The flange 16
Is formed in a tapered shape whose outer peripheral surface converges toward the core 3 side.

The inner peripheral surface of the flange 16 of the mover 10 and the outer peripheral surface of the core 3 opposed to the flange 16 are in contact with the independent surface 18 of the inner magnetic leakage portion 15 whose relative distance does not change with the movement of the mover 10. Has become.

Further, on the outer peripheral side of the mover 10, between the mover 10 and the case 1, in this embodiment, a yoke 19 attached to the inner periphery of the case 1 causes an outer magnetic leakage. An outer peripheral flange 21 forming the part 20 is formed. Outer peripheral surface of the outer peripheral flange 21 and the yoke 19
Is formed in a tapered shape converging toward the coil assembly 2 side.

Here, the outer peripheral flange 2 of the mover 10
1 and the inner peripheral surface of the yoke 19 opposed thereto
It is a correlation surface 22 of the outer magnetic leakage part 20 whose relative distance changes with the movement of the mover 10.

Numeral 25 denotes an anti-suction shim provided between the mover 10 and the end face of the core 3. The attraction prevention shim 25 is formed in a thin plate shape from a non-magnetic material such as rubber or synthetic resin, and is disposed on the outer peripheral side of the support projection 13 to prevent the movable element 10 from adsorbing to the end face of the core 3. doing.

A spring member 26 is provided between the bearing 14 and the end face of the core 3. The spring member 2
Numeral 6 is accommodated in the through hole 11 of the mover 10, one end of which is in contact with the bearing 14, and the other end of which is in contact with the suction prevention shim 25, and biases the bearing 14 in a direction away from the core 3. .

Numeral 31 denotes a valve body connected to the mover 10. The valve body 31 is slidably inserted into a sealing plate 32 fixed to the other end of the case 1 by caulking and a valve hole 34 formed in a passage forming body 33 integrated with the sealing plate 32. Housed.

The valve element 31 is a so-called spool valve having a threading shape in this embodiment, and has a large-diameter land portion 35, a small-diameter land portion 36, and a portion between the large-diameter land portion 35 and the small-diameter land portion 36. The large-diameter land portion 35 is inserted into the large-diameter portion 34a of the valve hole 34, and the small-diameter land portion 36 is inserted into the small-diameter portion 34b of the valve hole 34. At the same time, the end surface 38 on the large-diameter land portion 35 side is in contact with the mover 10 and the bearing 14. The valve element 31 has an axial through hole 39 formed therein.

The valve element 31 is connected to the mover 10 by contacting the end face 38 of the large-diameter land portion 35 on the mover 10, and via a bearing 14 that comes into contact with the mover 10. 1 and is constantly urged leftward in FIG. 1 by this spring force.

Withdrawal of the valve element 31 from the inside of the valve hole 34 is as follows.
It is prevented by a stopper plate 40 provided at the opening end of the valve hole 34. A through hole 41 is formed substantially at the center of the stop plate 40 so as to coincide with the through hole 39 of the valve element 31.

On the other hand, a pump 4
An introduction hole 44 communicating with the second discharge passage 43, a supply hole 46 communicating with a supply passage 45 to the actuator (not shown), and a drain hole 48 communicating with a drain passage 47 are formed. The introduction hole 44 is opened at the small diameter portion 34 b of the valve hole 34, and can be opened and closed by the small diameter land portion 36 of the valve body 31. The supply hole 46 and the drain hole 48 are provided in the valve hole 3.
4 is open to the large diameter portion 34a, and only the drain hole 48 can be opened and closed by the large diameter land 35 of the valve element 31.

Reference numeral 49 denotes a working fluid reservoir. In addition,
As the working fluid, either a liquid or a gas can be adopted.

Next, the operation of the solenoid valve having such a configuration will be described.

First, when a control current is not supplied from a control device and a power supply (not shown) to the electromagnetic coil 5 of the coil assembly 2 (non-energized state), the movable element 10 and the valve element 31 In FIG. 1, the valve element 31 is urged to the left by force, whereby the valve element 31 comes into contact with the stop plate 40 and stops, and is in the state shown in the upper half of FIG. 1.

In the non-energized state, the introduction hole 44 of the passage forming body 33 is opened in the valve hole 34 without being closed by the small-diameter land portion 36 of the valve body 31, while the drain hole 48 is formed in the valve body 31. Is closed by the large-diameter land portion 35. Thereby, the discharge passage 43 and the introduction hole 4
4, the pressure of the working fluid introduced into the valve hole 34 becomes a predetermined pressure (A pressure) based on the discharge pressure of the pump 42, and the predetermined pressure (A pressure) passes through the supply hole 46 and the supply passage 45. Act on an actuator not shown in the figure.

At this time, the valve element 31 receives the pressure of the working fluid introduced into the valve hole 34 from the pump 42.
Since the valve element 31 has a difference in pressure receiving area between the large-diameter land portion 35 and the small-diameter land portion 36, the pressure of the working fluid acts on the respective pressure receiving surfaces, so that the valve element 31 has the pressure receiving area. The force generated by the difference acts. Specifically, the force (thrust force) acts on the valve element 31 in the direction of the large-diameter land portion 35 (rightward in the figure).

The thrust force acting on the valve element 31 acts on the mover 10 and the bearing 14, and presses the mover 10 and the bearing 14 rightward in the drawing against the spring member 26. In the non-energized state of the coil 5, the spring force of the spring member 26 exceeds the thrust force generated in the valve body 31 by the pressure of the working fluid, so that the valve body 31 is stopped by the spring force of the spring member 26. Board 4
It is in a state where it is in contact with 0, and in this state, it controls the pressure control.

Next, when a control current is applied to the electromagnetic coil 5 (energized state), a magnetic field is generated in the electromagnetic coil 5 according to the magnitude of the control current (or voltage). As a result, the magnetic field generated by the electromagnetic coil 5 reaches the core 3 through the case 1, the yoke 19, the outer magnetic leakage part 20, the mover 10, and the inner magnetic leakage part 15, and as a result, the mover 10 It is sucked to the core 3 side.

The force with which the mover 10 is attracted changes according to the magnitude of the control current (or voltage) applied to the electromagnetic coil 5, and the mover 10 is moved by the spring member 26 according to the attraction force. And moves closer to the core 3 against the spring force.

The valve element 31 receives a thrust force generated by the pressure of the working fluid introduced into the valve hole 34 at the same time that the movable element 10 is attracted and moves toward the core 3 side. The body 31 has its end face 38
Moves to the right while in contact with the mover 10 and the bearing 14, and changes from the state shown in the upper half of FIG. 1 to the state shown in the lower half.

When the electromagnetic coil 5 is energized, the valve body 31 moves rightward from the state shown in the upper half of FIG. 1 to the state shown in the lower half of FIG. The drain portion 48 that has been closed by the large-diameter land portion 35 tends to be opened while the land portion 36 tends to be closed. As a result, the pressure of the working fluid in the valve hole 34 decreases, and the pressure of the working fluid acting on the actuator (not shown) from the supply hole 46 and the supply passage 45 becomes a predetermined pressure (A pressure) in a non-conductive state. From the pressure (B pressure).

At this time, the pressure of the working fluid in the valve hole 34 decreases, and the pressure of the working fluid guided from the supply hole 46 and the supply passage 45 decreases. Although the thrust force generated in the body 31 also decreases, the force for attracting the mover 10 by the electromagnetic coil 5 increases, so that the mover 10
And the valve element 31 moves against the spring force of the spring member 26. That is, the valve element 31 has a force obtained by adding a thrust force generated in the valve element 31 by the pressure of the working fluid in the valve hole 34 to the force for attracting the mover 10 by the electromagnetic coil 5, and the spring force of the spring member 26. Moves to a position where
The pressure control is performed at this balanced position.

The pressure of the working fluid controlled by the movement of the valve element 31 changes according to the amount of movement of the mover 10 toward the core 3 by application of a control current to the electromagnetic coil 5. Is decreased by approaching the core 3, and is increased by moving the mover 10 away from the core 3. The approach and separation of the mover 10 to and from the core 3 are controlled according to the magnitude of the control current (or voltage) applied to the electromagnetic coil 5, and the mover 10 is increased with the increase of the control current (or voltage). The armature 10 approaches the core 3 against the spring force of the spring member 26, and the mover 10 is separated from the core 3 by the spring force of the spring member 26 as the control current (or voltage) decreases.

As a result, the pressure of the working fluid is controlled so as to decrease as the control current (or voltage) to the electromagnetic coil 5 increases, and is controlled to a fluid pressure inversely proportional to the control current (or voltage). It becomes possible.

Here, the magnetic force passing through the inner magnetic leakage part 15 and the outer magnetic leakage part 20
And the magnetic force passing through the
, Both magnetic forces are added to give a large attractive force.

The inner magnetic leakage part 15 is
0, the outer magnetic leakage portion 20 is formed with the independent surface 18 whose relative distance does not change with the movement of the mover 10.
Are formed with the correlation surface 22 in which the relative distance changes with the movement of the magnetic field, the characteristics of the added attractive force given to the mover 10 by the inner magnetic leakage part 15 and the outer magnetic leakage part 20 are as follows. The mover 10 and the core 3 (or the yoke 1
A characteristic having a flat region in which the suction force does not change even when the relative distance to the item 9) changes is obtained (see FIG. 2).

That is, in the inner magnetic leakage portion 15 formed by the independent surface 18 whose relative distance does not change with the movement of the mover 10, the attraction force to the mover 10 decreases as the mover 10 approaches the core 3. Characteristics (proportional characteristics)
On the other hand, in the outer magnetic leakage portion 20 formed by the correlation surface 22 in which the relative distance changes as the mover 10 moves,
As the mover 10 approaches the yoke 19, a characteristic (inverse proportional characteristic) in which the suction force on the mover 10 increases is shown.

Since the inner magnetic leakage part 15 has the independent surface 18 and the outer magnetic leakage part 20 has the correlation surface 22,
The solenoid valve has a characteristic in which both the proportional characteristic and the inverse proportional characteristic are added as the attractive force characteristic to the mover 10. For this reason, the characteristic of the added attractive force given to the mover 10 by the inner magnetic leakage part 15 and the outer magnetic leakage part 20 is that the movable element 10 and the core 3 (or the yoke 19)
Thus, a characteristic having a flat region in which the suction force does not change even if the relative distance to the element changes.

Accordingly, a large suction force can be applied to the mover 10, and even if the distance between the core 3 and the mover 10 changes, the suction force acting on the mover 10 does not change. A solenoid valve having various characteristics can be obtained.

When the mover 10 moves and approaches the core 3, an annular flange 16 formed on the mover 10 is formed between the coil insertion portion 6 of the bobbin 4 and the core 3. Since the inner magnetic leakage portion 15 is formed by entering the gap 8 formed, the size of the electromagnetic valve can be reduced.

That is, since the annular flange 16 of the mover 10 enters the gap 8, the end of the core 3 does not protrude greatly from the end face of the coil assembly 2, and the solenoid valve is moved in the axial direction. There is no lengthening.

In particular, the coil insertion portion 6 of the bobbin 4
Is only located at the connection end of the electromagnetic coil 5. Even if the gap 8 is formed on the inner peripheral side, the generation of the magnetic force by the electromagnetic coil 5 does not have a particularly bad influence.

Therefore, the axial dimension can be reduced,
An electromagnetic valve that can be reduced in size can be obtained.

The gap 8 into which the flange 16 of the mover 10 enters is formed by enlarging the inner diameter of the coil insertion section 6, so that the diameter of the core 3 is not reduced. The area of the magnetic path of the inner magnetic leakage portion 15 formed between the movable member 3 and the flange 16 of the mover 10 can be increased.

The inner diameter of the coil insertion portion 6 is tapered so that the inner diameter gradually increases toward one end of the bobbin 4, so that the shape of the annular flange 16 formed on the mover 10 is increased. Can be formed into a tapered shape that matches the shape of the gap 8. For this reason, the flange 16
Since the area at the front end is small, and magnetic saturation occurs on the front end side, the lines of magnetic force are formed inclined with respect to the radial direction, so that the attractive force of the electromagnetic coil 5 on the mover 10 can be increased.

FIG. 3 is a drawing showing another embodiment of the present invention.

In the embodiment shown in FIG. 3, the inner magnetic leakage part 15 is formed with a correlation surface 51 whose relative distance changes with the movement of the mover 10, while the outer magnetic leakage part 20 is formed. And an independent surface 52 whose relative distance does not change as the mover 10 moves.

In the above embodiment, the case 1 and the core 3 formed integrally with each other are separately formed, and the core 3 is inserted and fixed in the through hole 1a formed in the case 1. The sealing plate 32 and the passage forming body 33, which are also formed integrally with each other, are formed separately, and are connected to each other via a pressure tube 53.

That is, the sealing plate 32 is formed in an annular shape,
It is fixed in the case 1 so that its outer peripheral side is in contact with the inner peripheral side of the case 1, and a cylindrical pressure tube 53 is inserted into the annular inside of the sealing plate 32 so that one end of the pressure tube 53 The passage forming body 33 is fixed.

The pressure tube 53 is made of a non-magnetic material. The other end of the pressure tube 53 is reduced in diameter and fixed to the outer periphery of the core 3.

The mover 10 is accommodated slidably in the axial direction in the cylindrical inside of the pressure tube 53. The pressure tube 53 also serves as a bearing for slidably supporting the mover 10. Therefore, in this embodiment, the support projection 13 and the bearing 14 of the above embodiment are omitted.

The accommodating position of the mover 10 is located on the inner peripheral side of the sealing plate 32, and the sealing plate 32 also serves as a yoke for forming the outer magnetic leakage portion 20 with respect to the movable plate 10. ing.

The movable element 10 has an end face on the core 3 side,
An annular flange 16 forming an inner magnetic leak 15 is formed. The flange is 16 and its inner peripheral surface is the core 3.
It is formed in a tapered shape whose diameter increases toward the side.

The outer peripheral surface at the end of the core 3 facing the inner peripheral surface of the flange 16 has a taper converging toward the mover 10 so as to match the tapered shape of the inner peripheral surface of the flange 16. It is formed in a shape.

As a result, the inner peripheral surface of the flange 16 of the mover 10 and the outer peripheral surface of the core 3 opposed to the flange 16 change in relative distance as the mover 10 moves. The surface 51 is provided.

Further, on the outer peripheral side of the mover 10, between the mover 10 and the case 1, in this embodiment, a sealing plate 3 serving also as a yoke attached to the inner periphery of the case 1 is provided.
2, an outer peripheral flange 21 forming an outer magnetic leakage portion 20 is formed. The outer peripheral surface of the outer peripheral flange 21 is formed in a cylindrical shape similarly to the inner peripheral surface of the sealing plate 32.

Here, the outer peripheral flange 2 of the mover 10
1 and the inner peripheral surface of the sealing plate 32 opposed thereto
It is an independent surface 52 of the outer magnetic leakage portion 20 whose relative distance does not change with the movement of the mover 10.

In the embodiment shown in FIG. 3,
The spring member 26 is housed in a blind hole 54 formed in the end face of the core 3, and one end contacts the mover 10 via the suction prevention shim 25, and the other end contacts the bottom surface of the blind hole 54, and is movable. The child 10 is urged in a direction away from the core 3.

The valve element 31 has a protruding portion 55 formed on the large-diameter land portion 35 side, and the protruding portion 55 is connected to the movable element 10 by being in contact with the movable element 10. .

Since other structures are substantially the same as those of the above-described embodiment, the same components are denoted by the same reference numerals, and redundant description will be omitted.

In such a configuration, first, when no control current is supplied from a control device and a power supply (not shown) to the electromagnetic coil 5 of the coil assembly 2 (non-energized state), the movable element 10 and the valve element 31 3 is urged leftward in the figure by the spring force of the spring member 26, whereby the valve body 31 comes into contact with the stop plate 40 and stops.
In the state shown in the upper half, pressure control is performed in this state.

Next, when a control current is applied to the electromagnetic coil 5 (energized state), a magnetic field is generated in the electromagnetic coil 5 according to the magnitude of the control current (or voltage). As a result, the magnetic field generated by the electromagnetic coil 5 causes the case 1, the sealing plate 32 also serving as a yoke, the outer magnetic leakage portion 20,
The armature 10 reaches the core 3 through the mover 10 and the inner magnetic leakage portion 15, and as a result, the mover 10 is attracted to the core 3 side.
Thereby, the valve element 31 moves from the state shown in the upper half of FIG. 3 to the state shown in the lower half in a state where the protruding portion 55 is in contact with the mover 10, and controls the pressure in this state.

Thus, similar to the above embodiment,
The fluid pressure can be controlled based on the control of energization of the electromagnetic coil 5.

Here, the magnetic force passing through the inner magnetic leakage portion 15 and the outer magnetic leakage portion 20
And the magnetic force passing through the
, Both magnetic forces are added to give a large attractive force.

The inner magnetic leakage part 15 is
The outer magnetic leakage portion 20 is formed with an independent surface 52 whose relative distance does not change with the movement of the mover 10, while being formed with a correlation surface 51 whose relative distance changes with the movement of 0. Therefore, the characteristic of the added attractive force given to the mover 10 by the inner magnetic leakage part 15 and the outer magnetic leakage part 20 is a relative characteristic between the mover 10 and the core 3 (or the sealing plate 32 also serving as a yoke). A characteristic having a flat region in which the suction force does not change even when the distance changes (see FIG. 2).

That is, in the inner magnetic leakage portion 15 formed by the correlation surface 51 whose relative distance changes with the movement of the mover 10, as the mover 10 approaches the core 3, the attractive force to the mover 10 is increased. Of the outer magnetic leakage portion 20 formed by the independent surface 52 in which the relative distance does not change with the movement of the mover 10
In this case, as the mover 10 approaches the sealing plate 32 also serving as a yoke, a characteristic (proportional characteristic) in which the attraction force on the mover 10 is reduced.

Since the inner magnetic leakage part 15 has the correlation surface 51 and the outer magnetic leakage part 20 has the independent surface 52,
The solenoid valve has a characteristic in which both the inverse proportional characteristic and the proportional characteristic are added as the attractive force characteristic to the mover 10. Therefore, the characteristic of the added attractive force applied to the mover 10 by the inner magnetic leakage part 15 and the outer magnetic leakage part 20 is a relative characteristic between the mover 10 and the core 3 (or the sealing plate 32 also serving as a yoke). A characteristic having a flat region where the suction force does not change even when the distance changes is obtained.

Therefore, a large suction force can be applied to the mover 10, and even if the distance between the core 3 and the mover 10 changes, the suction force acting on the mover 10 does not change. A solenoid valve having various characteristics can be obtained.

Further, by fixing the passage forming body 33 to one end of the pressure tube 53 and fixing the other end to the outer periphery of the core 3, the working fluid leaking from between the valve hole 34 and the valve body 31. Can be hermetically sealed in the pressure tube 53.

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to this embodiment, and can be changed without departing from the spirit of the invention.
For example, a yoke 1 is provided between the mover 10 and the case 1.
Although the embodiment in which the outer magnetic leakage portion 20 is formed through the intermediary 9 has been described, the yoke 19 is eliminated and the
The outer magnetic leakage part 20 may be formed between the first magnetic field and the second magnetic field.

[0099]

As described above in detail, according to the present invention, a large suction force can be applied to the movable element, and the movable element can be moved even if the distance between the core and the movable element changes. An electromagnetic valve having flat characteristics in which the suction force acting on the child does not change can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of a solenoid valve according to an embodiment of the present invention;
The upper half is a drawing showing a state where power is not supplied to the electromagnetic coil, and the lower half is a drawing showing a state where power is supplied to the electromagnetic coil.

FIG. 2 is a diagram showing the attraction force characteristics of the mover by the electromagnetic coil of the electromagnetic valve of the present invention.

FIG. 3 is a view similar to FIG. 1, but showing another embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 case 2 coil assembly 3 core 4 bobbin 5 electromagnetic coil 10 mover 15 inner magnetic leakage part 18 independent surface 20 outer magnetic leakage part 22 correlation surface 31 valve body

Claims (5)

[Claims] 1. A substantially cylindrical coil assembly having a cylindrical case, a bobbin fixed inside the case, and an electromagnetic coil wound around the bobbin, and a cylindrical inside of the coil assembly. A fixed core, and a mover that is arranged on the shaft end side of the core and that can move toward and away from the core,
A valve body connected to the mover, an inner magnetic leakage portion formed between the mover and the core, and having an independent surface whose relative distance does not change with the movement of the mover; An electromagnetic valve, comprising: an outer magnetic leakage part formed between the case and a case, the outer magnetic leakage part having a correlation surface whose relative distance changes with movement of the mover. 2. A coil insertion portion in which a connection end of an electromagnetic coil is located at one end of a bobbin of the coil assembly, and an annular gap is formed between the coil insertion portion and the core. 2. The solenoid valve according to claim 1, wherein the movable element is formed with an annular flange that enters the gap to form an inner magnetic leakage part. 3. 3. The method according to claim 1, wherein the gap is formed by enlarging an inner diameter of the coil insertion portion.
The solenoid valve according to claim 2. 4. The solenoid valve according to claim 3, wherein the inner diameter of the coil insertion portion is tapered so that the inner diameter gradually increases toward one end of the bobbin. . 5. A substantially cylindrical coil assembly having a cylindrical case, a bobbin fixed to the case, and an electromagnetic coil wound on the bobbin, and a cylindrical interior of the coil assembly. A fixed core, and a mover that is arranged on the shaft end side of the core and that can move toward and away from the core,
A valve body connected to the mover, an inner magnetic leakage portion formed between the mover and the core, and having a correlation surface whose relative distance changes with the movement of the mover, An electromagnetic valve, comprising: an outer magnetic leakage portion provided between the case and the case and having an independent surface whose relative distance does not change with movement of the mover.