JPH0740135Y2 - Solenoid valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is arranged adjacent to a core in a space formed inside a body and moves toward and away from the core to open in the space. The present invention relates to a solenoid valve having a moving body that opens and closes a fluid inflow hole that controls the inflow of fluid into the space, and a fluid discharge hole that opens into the space and discharges the fluid that has flowed into the space.

[Prior Art] This type of solenoid valve is used in various fields, and is used in a hydraulic control device in an automatic transmission for automobiles (Shokai 59-52289, etc.).

FIG. 2 shows a solenoid valve of the above type used in a hydraulic control device for an automatic transmission for an automobile. In this solenoid valve, the plate 12 is fixed to the base 10, the yoke 14 is fixed to the plate 12, and the plate 16 is fixed to the yoke 14 to form a body 18. Body
A core 20 is arranged inside the core 18, and a coil 24 wound around a bobbin 22 is arranged around the core 20. A sleeve 26 is arranged between the core 20 and the coil 24.

In the sleeve 26, a core plunger 28 is arranged in a space formed inwardly so as to be movable in the axial direction with a slight gap from the sleeve 26. The core plunger 28 is biased in a direction away from the core 20 by a spring 30 arranged between the core plunger 28 and the core 20. Base for Core Plunger 28
Plungers 32 projecting into the space formed inward of 10 are fixed, and both form a moving body 33.

The plunger 32 is provided in the base 10 and can open and close an import 34 as a fluid inflow hole that opens to a space formed inside the base 10. The hydraulic oil that has flowed into the space formed inside the base 10 from the import 34 is drain port 36 as a fluid discharge hole that is drilled in the base 10 and opens in the space formed inside the base 10. Is to be discharged from.

In a solenoid valve constructed in this way, the coil 24
When the power is not supplied to the moving body 33, the moving body 33 is in the position shown in the figure against the hydraulic pressure of the hydraulic oil by the urging force of the spring 30, and the plunger 32 closes the import 34. It cannot flow into the space formed inside the base 10.

When the coil 24 is energized from this state, the core 20,
A magnetic circuit is configured by the plate 12, the yoke 14, the plate 16, the base 10 and the core plunger 28, and an attractive force is generated between the core plunger 28 and the core 20. This allows
The moving body 33 moves toward the core 20 against the urging force of the spring 30, and stops moving when the core plunger 28 is attracted to the core 20.

This movement of the moving body 33 causes the plunger 32 to open the import 34, so that the hydraulic oil flows into the space formed inside the base 10, and the hydraulic oil that has flowed in is discharged from the drain port 36. ing. The hydraulic oil discharged from the drain port 36 is circulated by an oil pump built in the automatic transmission main body.

When the energization of the coil 24 is stopped from this state, the suction force generated between the core plunger 28 and the core 20 disappears, so that the moving body 33 is biased by the spring 30 to move and is illustrated. It becomes the above state.

Here, when the moving body 33 is moved by being urged by the spring 30, a gap 38 is generated between the core 20 and the core plunger 28, and a negative pressure is generated in this portion. The hydraulic oil flowing into the space formed inwardly flows into the generation gap 38 through the gap formed between the sleeve 26 and the core plunger 28.

Then, the hydraulic oil that flows in here is pushed out when the moving body 33 moves against the urging force of the spring 30 contrary to the above, and moves to the space formed inside the base 10, and the import 34 Drain port 36 with hydraulic oil flowing in from
Emitted from. Therefore, every time the moving body 33 is urged by the spring 30 to move, the hydraulic oil flowing from the new import 34 flows into the gap 38 created between the core 20 and the core plunger 28. Will come.

[Problems to be solved by the invention] By the way, the hydraulic oil is supplied to the operating portion of the automatic transmission body and is also used as lubricating oil for lubrication, so that it flows from the import 34 into the solenoid valve. There is a case where minute metallic foreign matters are mixed in the hydraulic fluid.

If this fine metal foreign substance is carried to the gap 38 generated between the core 20 and the core plunger 28 by the hydraulic oil, the gap between the sleeve 26 and the core plunger 28 is small, so the fine metal foreign substance is present in this portion. It is difficult to get out of the room and tends to stay. As described above, every time the moving body 33 is moved by being biased by the spring 30, the hydraulic oil newly introduced from the import 34 flows into the gap created between the core 20 and the core plunger 28. Therefore, there is a possibility that an insignificant amount of fine metallic foreign matter may be accumulated for a long period of time and the core plunger 28 may not be able to move to the position where it abuts the core 20.

In such a state, the tip of the plunger 32 cannot be separated from the import 34 by a predetermined distance, so that the plunger 32 increases the flow path resistance and the solenoid valve does not satisfy the desired function, and The transmission cannot exhibit its original performance.

Such a problem is not limited to the solenoid valve used in the hydraulic control device for the automatic transmission for an automobile as described above, but can occur in common with this type of solenoid valve.

In view of the above, it is an object of the present invention to prevent a malfunction of a solenoid valve from being caused by foreign matter such as minute metal foreign matter mixed in fluid such as hydraulic oil.

[Means for Solving the Problems] The present invention is arranged adjacent to the core in a space formed inside the body and has a gap between the inner circumference of the body and a direction toward and away from the core. A moving body that moves to open and close the fluid inflow hole that opens into the space to control the inflow of fluid into the space, and a fluid discharge hole that opens into the space and discharges the fluid that has flowed into the space. A solenoid valve having a fluid passage hole that opens to the space closer to the core than the fluid discharge hole, and an intermediate portion between the portion where the fluid discharge hole is opened and the portion where the fluid passage hole is opened. The fluid passage formed by the space portion is narrowed by the moving body, and the fluid communication hole is defined by the volume of the gap between the moving body and the core when the moving body closes the fluid inflow hole. The total volume of the internal space of the Is characterized by.

[Operation] In the present invention having the above-described configuration, the fluid flowing out from the gap generated between the moving body and the core has a narrow fluid passage in the intermediate portion between the fluid communication hole and the fluid discharge hole. It does not flow into the fluid communication hole and is not discharged via the fluid discharge hole.

Further, the fluid flowing into the gap generated between the moving body and the core flows in from the fluid conducting hole and is imported because the fluid passage in the middle portion between the fluid conducting hole and the fluid discharging hole is narrow. Will not flow in through.

Therefore, the fluid flowing into the generation gap and flowing out from this gap flows along a different fluid flow path from the fluid flowing in from the fluid inflow hole and discharged from the fluid discharge hole. Foreign matter mixed in the fluid flowing in from the inflow hole and discharged from the fluid discharge hole does not accumulate in the gap generated between the moving body and the core.

Further, in the present invention, since the total volume of the internal space of the fluid conducting hole is set to be larger than the volume of the gap between the moving body and the core when the moving body closes the fluid inflow hole, the moving body and the core are set. The liquid that has flowed out of the gap formed between the fluid passage and the inner periphery of the body and has flowed into the fluid communication hole remains in the fluid communication hole. That is, every time the moving body moves, it passes through the gap between the moving body and the inner circumference of the body,
The liquid that flows between the gap and the fluid communication hole is always the same, and this liquid is not circulated.

Therefore, foreign matter mixed in the fluid outside the fluid communication hole does not accumulate in the gap created between the moving body and the core.

[Embodiment] FIG. 1 shows the present invention in an ECT for an automobile.
An embodiment applied to a solenoid valve for a hydraulic pressure control device of a controlled transmission) is shown.

In the solenoid valve of this embodiment, the cylindrical yoke 40
An outer flange portion 40A projecting outward and an inner flange portion 40B projecting inward are formed at one end portion of the. One end of the base 42 is fitted and locked to the inner flange portion 40B, and the yoke 40 and the base 42 form a body 44. Inside the body 44, coaxially with the yoke 40,
That is, a cylindrical core 46 is arranged coaxially with the body 44, and an outer peripheral edge of a flange portion 46A formed at one end portion of the core 46 is caulked and fixed to the other end portion of the yoke 40.

The tip of the core 46 is fitted into the sleeve 50 via an O-ring 48. The sleeve 50 has a distal end protruding inwardly of the base 42 into a space formed by a stepped hole so that the base 42
The space formed inside is communicated with the space of the base 42.

A coil 54 is wound around a bobbin 52 around the outer periphery of the sleeve 50.
Are arranged over substantially the entire length of the yoke 40. Bobbins
One end of 52 passes through a notch formed in the flange portion 46A of the core 46 and projects to the outside of the yoke 40. Coil 54
The terminal of is connected to a terminal 56 protruding to the outside of the yoke 40, and the terminal 56 is connected to a lead wire 58. The terminal 56 is a rubber boot 60 that is attached to the end of the yoke 40.
Of the rubber boot 60, and is embedded in the epoxy resin 62 filled inside the rubber boot 60. The epoxy resin 62 extends from the notch formed in the flange portion 46A of the core 46 to the yoke 40
And enters the gap between the yoke 40 and the coil 54, the gap between the core 46 and the bobbin 52, and the like.

The space of the base 42 is coaxial with the base 42, that is, coaxial with the body 44 and communicates with the outside through an import 64 formed in the base 42, and the axis is in the radial direction of the body 44. It communicates with the outside through a plurality of drain ports 66 drilled in 42.

Further, the space portion of the base 42 is adjacent to the tip of the sleeve 50 and opens into the space portion of the base 42, and a plurality of hydraulic oil passage holes 68 as fluid passage holes whose axis is inclined with respect to the axis of the body 44 are provided. And communicate with the outside. The hydraulic oil passage hole 68 opens outside the base 42 near the drain port 66.

A core plunger 70 is disposed in the space of the sleeve 50 so as to be movable in the axial direction with a slight clearance from the sleeve 50. A stepped through hole is formed coaxially with the body 44 in the core plunger 70, and one end of the plunger 72 is fitted and locked in the small diameter portion of the through hole to form a moving body 76 with both. There is. Plunger 72 protruding from core plunger 70
Has a stepped round bar shape, and the tip has a conical shape. In the large diameter portion of the through hole of the core plunger 70, a spring 74 made of a compression coil spring is housed with its end face in contact with the stepped portion. The other end of the spring 74 is housed in a recess formed in the tip surface of the core 46.

As a result, the spring 74 urges the moving body 76 to press the tip end portion of the plunger 72 against the opening end surface of the import 64 to close the import 64. In this state, a gap 78 is formed between the core plunger 70 and the core 46.

When the coil 54 is energized, the moving body 76 compresses the spring 74 by the attractive force generated between itself and the core 46, and
, The core plunger 70 contacts the core 46, and the gap 78 becomes zero. In this state, the tip of the plunger 72 is separated from the import 64, and the import 64 and the drain port 66 are communicated with each other through the space of the base 32.

Here, the volume of the gap 78 when the plunger 72 is blocking the import 64 is a value obtained by multiplying the separation length between the core 46 and the core plunger 70 by the cross-sectional area of the inner diameter portion of the sleeve 50. The total volume of the space volume of the plurality of hydraulic oil communication holes 68 is set to be larger than this value.

Further, the inner diameter of the space portion of the base 42 in the portion where the drain port 66 is opened is smaller than that in the portion where the hydraulic fluid passage hole 68 is opened, and the plunger 72 is always provided in this small diameter portion. It corresponds to the large diameter part. As a result, the plunger 72 has the drain port 66 and the hydraulic fluid passage hole 68.
The hydraulic oil passage between and is narrow.

An O-ring 80 and an O-ring 82 are fitted to the small-diameter portion and the large-diameter portion, respectively, on the outer peripheral portion of the base 42 protruding from the yoke 40.

The solenoid valve of the present embodiment configured in this way,
It is arranged in the valve body of the hydraulic control device. In this arrangement, the base 42 is inserted into the stepped oil hole formed in the valve body so that the small diameter portion and the large diameter portion of the base 42 are O-rings.
The import 64 is connected to the oil pressure generation oil passage through the 80 and the O-ring 82, and the drain port 66 and the hydraulic oil passage 68 are communicated with the oil passage guided to the oil pan. The outer flange portion 40A of the yoke 40 contacts the valve body.

Next, the operation of this embodiment will be described.

When the coil 54 is not energized, the moving body 76
Is located at the position shown in the figure against the hydraulic pressure of the hydraulic oil by the urging force of the spring 74, and the plunger 72 closes the import 64, so that the hydraulic oil does not flow into the space formed inside the base 42. Can not flow. In this state, sleeve 50 and base
The space formed inside 42 is filled with hydraulic oil.

When the coil 54 is energized via the lead wire 58 and the terminal 56, a magnetic circuit is constituted by the core 46, the yoke 40, the base 42 and the core plunger 70, and the core plunger 70
A suction force is generated between the core 46 and the core 46. As a result, the moving body 76 moves toward the core 46 against the biasing force of the spring 74, and stops moving while the core plunger 70 is attracted to the core 46. This movement of the moving body 76 causes the plunger 72 to open the import 64, so that the hydraulic oil flows into the space formed inside the base 42, and the hydraulic oil that has flowed in is discharged from the drain port 66 to the oil pan. Carried. The hydraulic oil discharged from the drain port 66 is circulated by an oil pump built in the main body of the automatic transmission.

Further, the movement of the moving body 76 causes the hydraulic oil that has flowed into the gap 78 between the core 46 and the core plunger 70 to be pushed out of the gap 78, and passes through the gap between the sleeve 50 and the core plunger 70 to cause the base 42. It moves to the space formed inside. Since the hydraulic oil passage hole 68 is opened in this portion, the hydraulic oil flowing out of the gap 78 flows into the hydraulic oil passage hole 68. As described above, the total space volume of the hydraulic oil passage hole 68 is
Since 72 is set to be larger than the value of the volume of the gap 78 when the import 64 is blocked, the hydraulic oil that has flowed into the hydraulic oil passage hole 68 stays in the hydraulic oil passage hole 68. Not carried to bread.

Since the hydraulic oil passage between the hydraulic oil communicating hole 68 and the drain port 66 is narrowed by the large diameter portion of the core plunger 70, the hydraulic oil flowing out from the gap 78 is drained from the drain port 66.
To flow into the hydraulic oil passage hole 68 without going to.

When the energization of the coil 54 is stopped from this state, the suction force generated between the core plunger 70 and the core 46 disappears, so that the moving body 76 is urged by the spring 74 to move and is illustrated. It becomes the above state.

Further, when the moving body 76 is moved by being biased by the spring 74, the gap 78 between the core 46 and the core plunger 70 is enlarged, and a negative pressure is generated in the gap 78. The negative pressure is sucked and the hydraulic oil in the hydraulic oil communication hole 68 flows into the gap 78 (for the same reason as above, the hydraulic oil flowing from the import 64 is changed to the gap 78).
There is no going to. ). The hydraulic oil that has flowed into the gap 78 has flowed out from the gap 78 when the moving body 76 moved the previous time. That is, every time the moving body 76 moves, the hydraulic fluid flowing between the gap 78 and the hydraulic fluid communication hole 68 is always the same, and this hydraulic fluid is not circulated like other hydraulic fluids.

Therefore, since minute metal foreign matters are not brought into the gap 78, they are not deposited in the gap 78,
Even when used for a long period of time, the moving body 76 can always retract to a predetermined position.

As described above, when the present invention is applied to the hydraulic control device of the ECT, it can contribute to the improvement of durability against abnormal wear in the automatic transmission and the extension of the life of the entire automatic transmission.

[Effects of the Invention] As described above, the solenoid valve according to the present invention has an excellent effect that a defect does not occur due to foreign matter mixed in the fluid.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a solenoid valve according to the present invention, and FIG. 2 is a vertical sectional view showing a conventional solenoid valve. 44 …… Body, 64 …… Import, 66 …… Drain port, 68 …… Hydraulic fluid passage hole, 76 …… Movement, 78 …… Gap.

Claims (1)

[Scope of utility model registration request] 1. A space which is formed inside the body and is adjacent to the core, has a gap between the inner circumference of the body, and moves toward and away from the core to open in the space. A solenoid valve having a moving body that opens and closes a fluid inflow hole to control the inflow of fluid into the space, and a fluid discharge hole that opens into the space and discharges the fluid that has flowed into the space A fluid-conducting hole that opens to the space is provided closer to the core than the discharge hole, and a fluid formed by the space that is an intermediate portion between the portion where the fluid discharge hole is opened and the portion where the fluid-communication hole is opened. The passage is narrowed by the moving body, and the total volume of the internal space of the fluid communication hole is set to be larger than the volume of the gap between the moving body and the core when the moving body closes the fluid inflow hole. Solenoid valve .