JP2003287152A - solenoid valve - Google Patents

Abstract

(57) [Problem] To provide an electromagnetic valve capable of preventing leakage of ATF from the inside of the electromagnetic valve to the outside and obtaining stable characteristics when energizing a coil. A solenoid valve (1) includes a solenoid (10) and a seat (30). The moving core 16 of the solenoid unit 10 has a shaft 17
At the same time as the shaft 17 is energized. The rear end surface of the shaft 17 is formed so as to protrude from the rear end surface of the moving core 16,
A contact surface 177 that contacts the wall portion 18a of the magnetic sleeve 18 disposed inside the yoke 14 is formed. Coil 1
When the contact surface 177 of the shaft 17 comes into contact with the wall 18a of the sleeve 18 when the power is not supplied to the third 3, the gap 21 is formed between the rear end surface of the moving core 16 and the wall 18a of the sleeve 18.
Is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic valve which is mounted on, for example, an automatic transmission of a vehicle and in which a shaft or a moving core is pressed against a seat portion by an urging force such as a spring when not energized.

[0002]

2. Description of the Related Art Conventionally, for example, an electromagnetic valve built in an automatic transmission of a vehicle, in which a shaft or a moving core is pressed to the side opposite to a seat portion by an urging force such as a spring when not energized, is disclosed in Japanese Patent Laid-Open No. 2001-2001. 82
There is one shown in No. 625.

According to this, as shown in FIG. 3, the solenoid valve 50 is provided with a stator core 53 and a moving core 54 built in a hollow coil body 52, and the moving core 5 is provided.
4 is attracted to the stator core 53 when the coil 52a is energized, so that the movable shaft 54 and the movable shaft 55 are moved to the seat portion 60 side.

That is, the solenoid valve 50 has a stator core 53.
And a solenoid section 51 having a moving core 54 built-in,
And a seat portion 60 having an oil passage 64 that can be opened and closed by the tip portion of the shaft 55. Further, a part of a yoke 56 that covers the coil 52a is provided on the outer peripheral surface of the moving core 54. When the coil 52a is energized, magnetic flux flows through the yoke 56, the moving core 54, and the stator core 53 to form a magnetic circuit. The shaft 55 has a valve portion 55a which is inserted through the stator core 53 and can abut against the valve seat 61a of the seat member 61, and the rear end is inserted through the stator core 53 and abuts on the distal end portion of the moving core 54. It has a contact portion 55b. Then, the tip of the shaft 55 is formed to have a small diameter,
The ball member 62 provided inside the seat portion 60 can be pressed, and the moving core 54 moves to the stator core 53 side by energization of the coil 52a, so that the shaft 55 can be moved.
Was moved to the seat portion 60 side and the ball member 62 was pressed.

On the other hand, the seat portion 60 is provided with a fluid oil passage 64.
And a coil member 63 for urging the ball member 62 toward the solenoid portion 51 side.
When the shaft 55 is moved forward to the anti-solenoid portion 51 side by energizing the coil 52a, the ball member 62 is pressed by the fluid supplied from the input port 65, and the valve portion 55a of the shaft 55 is moved to the valve seat 61a of the seat member 61. When seated on, the oil passage 64 is opened so that the input port 65 and the output port 66 communicate with each other, and the output port 6
6 and the discharge port 67 are shut off. This allows the fluid in the input port 65 and the oil passage 64 to flow to the output port 66.

Also, the shaft 55 and the moving core 54 are moved toward the opposite side of the seat member 61 from the coil spring 6
When the moving core 54 is moved by the urging force of the moving core 54, the rear end portion of the moving core 54 is moved by the contact between the rear end surface of the moving core 54 and the stopper 57 by the disk-shaped stopper 57 attached to the rear end surface of the yoke 56. The movement of the core 54 is restricted.

[0007]

However, in the case where the solenoid valve 50 has the solenoid portion 51 attached to the outside of, for example, an automatic transmission (hereinafter referred to as AT), the fluid flowing into the moving core 54 is used. That is, since the automatic transmission fluid (hereinafter, referred to as ATF) leaks to the outside from between the stopper 57 with which the moving core 54 contacts and the mounting surface of the yoke 56, the solenoid portion 51.
There was a need to change the configuration inside. In this case, AT
In order to prevent leakage to the outside of F, the moving core 54
It is conceivable that the stopper 57 and the stopper 57 are integrally configured.

However, normally, when the coil 52a is energized, the yoke 56, the moving core 54, and the stator core 5 are
The magnetic flux flows through the magnetic flux 3 to form a magnetic circuit. However, when the moving core 54 and the stopper 57 are integrally formed, the magnetic flux flowing in the yoke 56 is
On the other hand, the magnetic flux flowing from the yoke 56 to the side surface of the moving core 54 and the magnetic flux flowing from the yoke 56 to the rear end surface of the yoke 56 via the stopper 57 are divided to form a magnetic circuit through two paths.

This causes a problem that the attraction force changes depending on the contact area between the rear end surface of the yoke 56 and the moving core 54 and the characteristics are not stable.

The present invention is to solve the above-mentioned problems, and when the solenoid portion is attached to the outside of the AT, the AT
An object of the present invention is to provide an electromagnetic valve capable of preventing leakage of F to the outside and stabilizing the characteristic of the attraction force of the solenoid portion.

[0011]

In order to solve the above-mentioned problems, the solenoid valve according to the present invention is characterized in that, according to the solenoid valve of the invention, the solenoid valve is energized / de-energized in the coil with respect to the stator core. It is equipped with a moving core that moves in the sleeve in the direction of approaching and separating. When the moving core approaches the stator core due to the energization of the coil, the shaft that passes through the moving core simultaneously moves to the seat portion side. At this time, in the solenoid portion, magnetic flux flows through the yoke, sleeve, moving core, and stator core to form a magnetic circuit. Since there is a gap between the wall of the moving core of the yoke that faces the axial direction and the rear end surface of the moving core, the magnetic flux that flows from the yoke to the sleeve flows to the moving core from the portion where the moving core of the sleeve is externally fitted. Therefore, almost no suction force works between the wall of the yoke and the rear end surface of the moving core. As a result, the suction force of the moving core that moves toward the stator core can obtain stable characteristics without change.

According to the second aspect of the invention, the fluid that has flowed into the sleeve tries to flow out through the outer peripheral surface of the sleeve along the inner wall of the yoke, but is blocked by the seal member and flows out. Not done. For example, in the engine room, the outside of the solenoid portion does not cause a fluid to enter the engine room, so that no trouble occurs.

According to the third aspect of the invention, the sleeve has the moving core fitted therein and has a wall portion axially opposed to the moving core. When the moving core approaches the stator core due to the energization of the coil, the shaft built in the moving core simultaneously moves to the seat portion side. At this time, in the solenoid portion, magnetic flux flows through the yoke, sleeve, moving core, and stator core to form a magnetic circuit. Since the axially opposed walls of the moving core of the sleeve and the rear end surface of the moving core have a gap, the magnetic flux flowing from the yoke to the sleeve flows to the moving core from the portion where the moving core of the sleeve is fitted. Therefore, the suction force hardly acts between the wall portion of the sleeve and the rear end surface of the moving core. As a result, the suction force of the moving core that moves toward the stator core does not change and stable characteristics can be obtained, as in the first aspect of the invention.

According to the fourth aspect of the invention, since the rear end of the shaft has the contact surface for contacting the wall of the sleeve, when the coil is switched from being energized to not being energized, When the shaft moves toward the sleeve and the contact surface of the shaft contacts the sleeve, a gap is formed between the moving core and the sleeve. Therefore, the suction force between the wall portion of the sleeve and the rear end surface of the moving core hardly acts. As a result, the suction force of the moving core that moves toward the stator core can obtain stable characteristics without change.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the solenoid valve 1 of the embodiment comprises a solenoid portion 10 and a seat portion 30. The seat portion is inserted into, for example, the AT room, and the solenoid portion is projected to the engine room side.

The solenoid portion 10 has a coil 13 wound around a bobbin 12 formed in a hollow shape, and the solenoid portion 10 is provided around the coil 13 and has a rear end side (right side in FIG. 1) closed to form a U-shaped cross section. The hollow coil assembly 11 is configured by integrally molding the bobbin 12 and the coil 13 with a resin, and further, the stator core 15 built in the coil assembly 11 and the stator core 15 are provided. A moving core 16 that is movable in a separating direction, a shaft 17 of a non-magnetic material that is inserted through the stator core 15 and the moving core 16, and a sleeve 18 that is fitted into the coil assembly 11 and that fits the moving core 16 outside. Is configured.

The sleeve 18 is formed of a magnetic material, and the contact surface 1 formed on the rear end surface of the shaft 17
It has a wall portion 18 a facing 77, is formed in a U-shaped cross section, and is fixed to the wall portion 14 a of the yoke 14.

Between the side surface of the bobbin 12 and the yoke 14, a seal groove 11a made of a resin material is provided with a yoke 1
The seal members (O-rings in the embodiment) 19 and 20 are attached to prevent the fluid flowing out through the wall portion 14a of No. 4 from leaking to the outside. The O-ring 19 is provided on the rear portion of the solenoid portion 10 so as to cover the wall portion 14 a of the yoke 14.
And the resin material forming a part of the coil assembly 11, the O-ring 20 is provided in the front portion of the solenoid portion 10, and is attached to the mounting flange portion 15 of the stator core 15.
1 and the resin material forming a part of the coil assembly 11.

The stator core 15 has a mounting flange portion 151 formed at a position where a portion built in the solenoid portion 10 and a portion protruding from the solenoid portion 10 toward the seat portion 30 along the axial direction are branched to form a seat flange portion 151. The side is inserted, for example, in the recess of the AT room of the vehicle. When the mounting flange portion 151 is attached to the outer wall portion of the AT room, the solenoid portion 10 is projected into the engine room, for example.

On the outer peripheral surface of the stator core 15, the above-mentioned A
Seal member mounting groove 152 for insertion into the recess of the T chamber
Is formed at a plurality of locations, and the tip portion (in FIG. 1,
The left side) 153 is formed as a case for forming the seat portion 10 and forms the seat portion 30. Stator core 1
The front end surface of 5 is opened to form the input port 32 by incorporating the cover 31 therein, and the input side seat portion 154 and the drain side seat portion 155 are provided behind the input port 32 in order toward the solenoid portion 10 side. , And is formed in a hollow wall shape orthogonal to the input port 32.

The output port 33 is formed between the input side seat portion 154 and the drain side seat portion 155 in the direction orthogonal to the axial direction, and the discharge port 34 is disposed in the axial direction behind the output port 33. Arrange in the orthogonal direction.

Further, the input side seat portion 154 and the drain side seat portion 155 are provided with an oil passage 156 having a small diameter along the axial center, and the shaft 1 extends from the drain side seat portion 155 in the stator core 15 toward the rear end surface.
A shaft sliding hole 157 is formed to insert the shaft 7.

A spherical ball 35, which is supported by a receiving seat 36, is arranged in the cover 31 built in the front portion 153 of the stator core 15 so as to be able to block the oil passage 156 and move in the axial direction. The O-ring 3 as a seal member is provided in the seal member mounting groove 152 of the stator core 15.
8 is attached.

The shaft 17 inserts the stator core 15 and the moving core 16 and moves in the oil passage 156 in order toward the seat portion 30 side to form a small diameter portion 171 and a valve portion 172 that can press the ball 35. And a large diameter portion 174 that slides in the stator core 15 and a moving medium core 1.
6, a rear intermediate diameter portion 175 that is inserted through the inside of the movable core 16 and is fitted into the moving core 16 by press fitting or the like, a step surface 176 that arranges the large diameter portion 174 and the rear intermediate diameter portion 175 in a step shape, the moving core 16
And a contact surface 177 formed on the rear end surface while protruding from the rear end surface.

The small diameter portion 171 of the shaft 17 has the ball 3
5 is pressed to open the oil passage 156 to connect the input port 32 and the output port 33, and the front middle diameter portion 173 is moved leftward, so that the valve portion 172 causes the drain side port 155 to move. It sits on the valve seat 158 on the rear end face. As a result, the output port 33 and the discharge port 34 are closed. Coil spring 3 to be mounted on the front middle diameter portion 173
Reference numeral 9 denotes a contact surface 177 formed on the rear end surface of the shaft 17 for urging the large diameter portion 174 toward the solenoid portion 10.
To act on the sleeve 18 in a pressable manner. Large diameter part 174
And a step surface 176 disposed between the rear intermediate diameter portion 175 and
By contacting the tip of the moving core 16,
The shaft 17 is moved in the axial direction along with the movement of the moving core 16.

Therefore, the seat portion 30 is composed of the stator core 1
5, the front portion 153, the cover 31, the ball 35, and the receiving seat 3
6, the input side seat portion 154, the output side seat portion 155 including the valve seat 158, the input port 32, the oil passage 156, the output port 33, and the discharge port 34.

Next, the operation configured as described above will be described.

Since the magnetic circuit is not formed in the solenoid portion 10 when the coil 13 in the solenoid portion 10 is not energized, the moving core 16 is
Not attracted to the stator core 15. Therefore, due to the biasing force of the coil spring 39, the shaft 17 moves to the sleeve 18
Is moved toward the wall 18a (rightward in FIG. 1). When the shaft 17 moves to the right, the moving core 16 also moves at the same time.

In this state, in the seat portion 30,
By moving the shaft 17 to the right, the small diameter portion 1
71 is located away from the ball 35, and the ball 35 abuts on the input side seat portion 154 by the pressure of the fluid from the input port 32 to close the oil passage 156 and close it. At the same time, the valve portion 17 of the front middle diameter portion 173 of the shaft 17
2 opens the valve seat 158 of the drain side seat portion 155, so that the fluid in the oil passage 156 and from the output port 33 flows to the discharge port 34.

On the other hand, in the solenoid portion 10, the contact surface 177 of the rear end surface of the shaft 17 contacts the wall portion 18a of the sleeve 18 and its rightward movement is restricted.
Since the contact surface 177 is arranged so as to project from the rear end surface of the moving core 16, when the contact surface 177 is in contact with the wall portion 18 a of the sleeve 18, the moving core 1
6 between the rear end surface and the wall portion 18a of the sleeve 18,
The void portion 21 will be formed.

Next, when the coil 13 is energized, a magnetic circuit is formed in the solenoid portion 10 and the moving core 1
6 is moved by suction to the stator core 15. That is, by moving the moving core 16 to the left, the small-diameter portion 171 of the tip of the shaft 17 presses the ball 35 to open the closed oil passage 156. This allows input port 32
The fluid supplied from flows through the oil passage 156 toward the output port 33. Further, the valve portion 172 of the front medium diameter portion 173 is seated on the valve seat 158 of the drain side seat portion 155, so that the output port 33 and the discharge port 34 are formed.
Are cut off, and the fluid supplied from the input port 32 flows to the output port 33 through the oil passage 156.

At this time, the yoke 14 and the moving core 1
6. Since the sleeve 18 is made of a magnetic material and the shaft 17 is made of a non-magnetic material, the magnetic flux generated by the energization of the coil 13 is, on the other hand, the yoke 1
4 through the side wall of the sleeve 18
6 from the yoke 14 to the sleeve wall 18a
And tries to flow toward the rear end surface of the moving core 16. However, since there is a gap 21 between the wall portion 18a of the sleeve 18 and the rear end surface of the moving core 16, the magnetic flux actually flowing through this path is extremely small or does not flow.

Therefore, the magnetic flux mainly flows from the side surface of the sleeve 18 to the side portion of the moving core 16 and reaches the stator core 15 to form a magnetic circuit.

On the other hand, the high-pressure fluid flowing into the stator core 15 passes from the inner peripheral sliding surface of the stator core 15 to the outer peripheral surface of the moving core 16, and from the outer peripheral surface of the sleeve 18 to the inner wall of the yoke 14. On the other hand, it flows toward the front of the coil assembly 11 and the mounting flange portion 151 of the stator core 15
And the yoke 14 try to flow out. If the fluid leaks from the solenoid unit 10 to the outside, if the solenoid unit 10 of the embodiment is arranged in the engine room, for example, a trouble may occur in the engine room.

However, at the rear portion of the solenoid portion 10, the O-ring 19 is mounted between the yoke 14 and the resin material forming a part of the coil assembly 11, and at the front portion of the solenoid portion 10, the mounting flange portion of the stator core 15 is attached. Since the O-ring 20 is arranged between the 151 and the resin material forming a part of the coil assembly 11, the high-pressure fluid is prevented from flowing out.

As described above, according to the solenoid valve 1 of the embodiment, the wall portion 18 of the sleeve 18 is provided at the rear end portion of the shaft 17.
the shaft contact surface 17
Since 7 projects from the rear end surface of the moving core 16, when the coil 13 is switched from energized to non-energized, the shaft 17 moves toward the sleeve 18 and the contact surface 177 of the shaft 17 contacts the sleeve 18. When they come into contact with each other, a gap 21 is formed between the moving core 16 and the sleeve 18.

When the coil is energized in this state, the yoke 1
4, magnetic flux flows through the sleeve 18, the moving core 16, and the stator core 15 to generate a magnetic circuit. Sleeve 18
Since the wall portion 18 a of the moving core 16 and the rear end surface of the moving core 16 have the void portion 21, the magnetic flux flowing from the yoke 14 to the sleeve 18 is mainly generated by the moving core 1 of the sleeve 18.
6 flows to the moving core 16 from the side to which the sleeve 6 is fitted, and almost no suction force acts from the wall portion 18a of the sleeve 18 to the rear end surface of the moving core 16. As a result, the suction force of the moving core 16 moving toward the stator core 15 can obtain stable characteristics without change.

On the other hand, the fluid flowing into the sleeve 18 from the inner peripheral sliding surface of the stator core 15 is
8 flows out through the outer peripheral surface of the yoke 14 along the inner wall of the rear portion of the yoke 14, but is blocked by the O-ring 19 and does not flow outside. The fluid flowing along the inner wall side of 151 is blocked by the O-ring 20 and blocked from flowing out. The outside of the solenoid is, for example,
In the engine room, no fluid will enter the engine room, so no trouble will occur.

In the embodiment, the sleeve 18 is formed in a U-shaped cross section having the wall portion 18a, but the present invention is not limited to this and may be, for example, a tubular shape as shown in FIG. . That is, the contact surface 177 on the rear end surface of the shaft 17 may contact the wall portion 14a of the yoke 14 instead of the wall portion 18a of the sleeve 18.
Even in this case, since the void portion 21 is formed between the rear end surface of the moving core 16 and the wall portion 14a of the yoke 14, the magnetic flux flowing from the yoke 14 to the sleeve 18 is the same as in the above-described embodiment. Mainly, the moving core 16 of the sleeve 18 flows to the moving core 16 from the side part fitted on the outer side of the moving core 16, and the suction force hardly acts from the wall portion 14a of the yoke 14 to the rear end surface of the moving core 16. As a result, the suction force of the moving core 16 moving toward the stator core 15 can obtain stable characteristics without change.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a solenoid valve according to one embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a state in which a sleeve of another form in FIG. 1 is arranged.

FIG. 3 is a sectional view showing a conventional solenoid valve.

[Explanation of symbols]

1 Solenoid valve 10 Solenoid part 13 coils 14 York 14a wall 15 Stator core 16 Moving Core 17 shaft 176 Step surface 177 Contact surface 18 sleeves 18a wall 19 O-ring 20 O-ring 21 void 30 seats 32 input ports 33 output ports 34 Discharge port 35 balls 39 coil spring 154 Input side sheet 155 Output side sheet 156 oil passage

Claims (4)

[Claims] 1. A stator core, a moving core that moves in a direction toward and away from the stator core, and a shaft that is movable together with the moving core, and the moving core energizes a coil that surrounds the moving core. A sheet portion that is movable by being de-energized and that has a solenoid portion that includes a yoke that covers the coil, and an oil passage that allows fluid to flow at the tip portion of the shaft, and that acts to let the fluid flow in and out. An electromagnetic valve comprising: the yoke having wall portions facing each other in a moving direction of the moving core, wherein the moving core inserts the shaft into the moving core and externally fits the moving core. The moving core and the front part are movably arranged in a sleeve formed of a magnetic material. Yoke and an electromagnetic valve, characterized by being arranged with a gap portion during closest approach between the yoke of the moving core in the axial direction. 2. A seal member is disposed inside the yoke to prevent a fluid flowing into the sleeve from flowing out through the inner wall of the yoke to the outside. 1. The solenoid valve according to 1. 3. The sleeve has wall portions facing each other in the moving direction of the moving core, and the moving core and the sleeve are closest to each other in the axial direction between the moving core and the sleeve. The solenoid valve according to claim 1 or 2, wherein the solenoid valve is arranged so as to have a void portion at times. 4. The solenoid valve according to claim 3, wherein a rear portion of the shaft is formed to have an abutment surface capable of abutting the sleeve in the axial direction.