JPH09144929A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain strong rotational force, more certainly prevent deposition and adhesion of impurities, and previously prevent deterioration of controllability, by forming a conduction channel by a plurality of grooves formed on the side surface of a plunger. SOLUTION: The solenoid valve main body 2 of a solenoid valve 1 is formed of a small diametral part 6, a connecting part 7 connected to the small diametral part 6 and a large diametral part 8 connected to the connecting part 7, and a inflow channel 9 is formed of the small diametral part 6 and the connecting part 7. A seat 11 having a seat hole 10 is formed to the large diametral part 8, and a solenoid 16 is fitted around the seat 11. A cylindrical member 17 is fitted in a bobbin 14 so as to form a valve chamber 18, and a plunger 19 is fitted in the valve chamber 18. The plunger 19 is formed of a plunger main body 24 and a valve part 25, and a conduction channel 27 is formed on the side surface 26 of the plunger main body 24. The conduction channel 27 is formed of a first conduction groove 29 spirally formed on one side of a virtual surface 28 and a second conduction groove 30 spirally formed on the other side thereof so that the plunger 19 can be rotated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve used for controlling fluid such as hydraulic pressure.

[0002]

2. Description of the Related Art Conventionally, hydraulic machines for agriculture or construction,
Alternatively, as shown in FIG. 6, an electromagnetic valve 71 for controlling the hydraulic pressure of clutch engagement oil is used in an automatic transmission of an automobile.

An inflow passage 72 through which pressurized oil flows is provided at the lower end side of the solenoid valve 71, and a seat 74 having a seat hole 73 is formed at the upper end of the inflow passage 72. ing. At the upper part of the inflow path 72, the inflow path 7
The valve chamber 7 into which the second oil flows in through the seat hole 73.
5, a plunger 77 having a valve portion 76 for opening and closing the seat hole 73 on its lower end surface is slidably fitted in the valve chamber 75. The plunger 77
On the side surface of the straight groove 78, ...
Of the valve chamber 75 are formed at equal intervals.
An outlet 79 is formed on the upper wall of the upper wall to let out the oil sent through the straight grooves 78.

The solenoid valve 71 is provided with a solenoid 82 in which a coil 81 is wound around a bobbin 80 close to the inflow passage 72 so as to surround the valve chamber 75. When energized, the plunger 77 pressed upward by the hydraulic pressure from the inflow passage 72 is sucked toward the inflow passage 72 side, so that the valve portion 76 of the plunger 77 closes the seat hole 73. Is configured.

[0005]

However, when the solenoid valve 71 is used for a long time without maintenance, as shown in FIG. 7, the upper surface of the plunger 77, the plunger 77 and the plunger 77 are not shown. Impurities such as iron powder generated due to wear of gears and impurities such as dust contained in oil are accumulated between the inner wall surface 84 of the valve chamber 75 and the inner surface 84 of the valve chamber 75. Then, the stroke of the plunger 77 may be reduced, or the movement of the plunger 77 may be deteriorated, resulting in deterioration of the hydraulic pressure control characteristic.

The present invention has been made in view of such conventional problems, and an object thereof is to provide a solenoid valve capable of preventing deterioration of controllability.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a fluid which flows from a front side of the plunger into a plunger provided slidably in a valve chamber is provided. In the electromagnetic valve provided with a flow passage that allows the flow of fluid to the rear side of the jar, the flow passage is formed in a spiral shape.

That is, when the fluid flowing from the front side of the plunger passes through the spirally formed flow passage,
A rotational force in a direction opposite to the turning direction in which the flow passage extends is applied to the plunger, and the plunger is rotated by this rotational force.

Further, the passage is constituted by a plurality of grooves formed on the side surface of the plunger.

Therefore, the rotational force acting on the plunger is applied from a plurality of positions on the side surface of the plunger, that is, at the position farthest from the center of rotation, so that the rotational force acts more greatly. Further, since the flow passage is composed of a plurality of grooves, a larger flow amount of fluid can be secured.

Further, when the groove is assumed to be a virtual surface that bisects the plunger along the sliding direction, the first flow-through groove formed on one side of the virtual surface and the other And a second flow groove formed on the side.

That is, the first and second flow grooves formed inclined with respect to the flow direction of the fluid are compared with the case where the grooves are formed over the entire side surface of the plunger. Since the inclination angle is small, the passage speed of the fluid passing through both flow grooves is high. This ensures a larger flow rate of the fluid. Further, since the first and second flow grooves are provided on both sides of the virtual surface that divides the plunger into two equal parts, the plunger can obtain a stable rotational force.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the solenoid valve 1 according to the embodiment of the present invention is used in an agricultural or construction hydraulic machine, an automobile automatic transmission, or the like, as in the conventional example. It controls the hydraulic pressure of oil such as lubrication for gears of a transmission.

The solenoid valve body 2 of the solenoid valve 1 has a cylindrical small-diameter portion 6 which is fitted into an output port 4 of an object 3 to which pressurized oil is sent via an O-ring 5. It is composed of a cylindrical connecting portion 7 that is continuous with the small diameter portion 6 and contacts the wall surface of the object 3, and a cylindrical large diameter portion 8 that is continuous with the connecting portion 7 and has a larger outer dimension than the small diameter portion 6. . The small-diameter portion 6 and the connecting portion 7 communicate with each other, thereby forming an inflow passage 9 through which the oil flows. Inside the large-diameter portion 8, a seat 11 having a seat hole 10 projecting upward from the connecting portion 7 side is formed, and a spring washer 12 is fitted on the seat 11.

A solenoid 16 having a coil 15 wound around a bobbin 14 is inserted into the large-diameter portion 8 through an opening 13 in the upper portion. It is provided so as to be urged, and a cylindrical member 17 is fitted into the bobbin 14 so as to come into contact with the upper surface of the seat 11. In the large-diameter portion 8, the tubular member 17
A valve chamber 18 into which the oil in the inflow passage 9 flows in through the seat hole 10 is formed, and in the valve chamber 18,
A vertically movable plunger 19 is slidably provided. A cushioning member 20 and a plate 21 laminated on the solenoid 16 are externally fitted to the tubular member 17, and the tubular member 17 has a large-diameter portion so as to close the opening 13. It is pressed downward together with the cushioning member 20 and the plate 21 by a lid body 23 having an outlet 22 which is fixed by being caulked to 8.

On the other hand, as shown in FIGS. 2 and 3, the plunger 19 has a cylindrical plunger body 24.
And a valve portion 25 that opens and closes the seat hole 10 projecting from the lower end surface of the plunger main body 24, and the side surface 26 of the plunger main body 24 is provided with the valve portion below the plunger 19. A passage 2 for allowing the oil flowing in from the seat hole 10 to flow above the plunger 19.
7 are provided. When assuming a virtual surface 28 that bisects the plunger 19 in the vertical direction, the flow passage 27 has a first flow groove 29 formed in the side surface 26 on one side of the virtual surface 28. And the second flow groove 30 formed on the side surface 26 on the other side.
The reference numerals 9 and 30 extend from the lower edge of the plunger main body 24 to the upper edge thereof, and are formed in a spiral shape so as to turn rightward in FIG. 3 from the lower edge toward the upper edge.

In the solenoid valve 1 having the above-described structure, when the solenoid 16 is de-energized, the plunger 19 sucked downward by the solenoid 16 is oiled from the seat hole 10 as shown in FIG. The sheet hole 10 that has been closed by the valve portion 25 of the plunger 19 is pushed up by the pressure P of 1. This allows
The oil flows into the valve chamber 18 through the seat hole 10 and flows out along the first and second flow grooves 29 and 30 spirally formed on the side surface 26 of the plunger 19. Then, the plunger 19 has a rotational force F in a direction opposite to the turning direction in which the both flow channels 29 and 30 extend.
Is added, the plunger 19 rotates in the left direction L by this rotational force F. As a result, even when the oil contains impurities such as iron powder and dust, the impurities are deposited on the upper surface of the plunger 19 or the plunger 19 and the plunger 19 are brought into sliding contact with each other. It does not adhere to the inner wall surface of the valve chamber 18. Therefore, even when the plunger 19 is used for a long period of time, the stroke amount of the plunger 19 is reduced or the plunger 1
The movement of 9 does not deteriorate, and the controllability of the solenoid valve 1 can be prevented from being deteriorated.

The rotating force F is the same as the plunger 19
Since it is applied at the side surface 26 of the above, that is, at the position farthest from the center of rotation of the plunger 19, this rotational force F acts greatly. Then, the first and second flow grooves 29, 3
Since 0 is provided on both sides of the virtual surface 28 that divides the plunger 19 into two parts, a rotational force F is applied to the plunger 19 from both side surfaces with the virtual surface 28 as a boundary, and the plunger 19 is stabilized. A rotating force can be obtained. This allows
Even when the oil deteriorates and its viscosity becomes high, stable rotation can be continued while preventing a decrease in rotation speed.

Further, the first and second flow grooves 29, 30 formed so as to be inclined with respect to the oil flow direction are compared with the case where they are formed over the entire side surface of the plunger 19. Since the inclination angle becomes small, both flow channels 29, 30
The passing speed of the oil passing through is high. Therefore, it is possible to secure a large amount of flow rate, and, for example,
Even if iron powder is adsorbed by the residual magnetism of the solenoid 16, this can be pushed out from the outlet 22.

In addition, by rotating the plunger 19, oil can be circulated between the plunger 19 and the inner wall surface of the valve chamber 18 with which the plunger 19 slides. Lubricity is enhanced. This allows
Since the heat generation of the solenoid valve 1 can be suppressed and the cooling efficiency can be increased, the heat deterioration of the oil and the coil 15 of the solenoid 16 can be prevented, and the service life of the solenoid valve 1 can be extended. Further, by preventing the winding resistance of the coil 15 from increasing due to the heat rise, it is possible to prevent the exciting force of the solenoid 16 from decreasing, so that the solenoid valve 1 can obtain stable controllability over a long period of time. .

In the present embodiment, the flow passage 27 through which the oil flows is formed by a first flow passage groove 29 and a second flow passage groove 30 formed on both sides of the virtual surface 28. Although the one constructed by two articles is shown, for example, the plunger 19
The side surface 26 may be formed of a single flow groove that makes one rotation, or may be formed of a plurality of flow grooves of three, four, or five or more.

Further, as shown in FIGS. 4 and 5, the first, second and third flow passages 51 are formed at equal intervals.
It may be constituted by the flow grooves 52, 53, 54 of the above. In this case, since the flow rate of the oil passing through the flow grooves 52, 53, 54 is further increased, it is possible to control a large flow rate. The solenoid valve is suitable for.

Further, in the present embodiment, the flow passage 27
Although the one formed on the side surface 26 of the plunger 19 is shown, for example, a through hole is formed inside by forming a cylindrical cover on a cylindrical member in which a spiral groove is formed. It may be a plunger.

[0024]

As described above, in the solenoid valve of the present invention, when the fluid passes through the passage of the plunger,
Since the plunger rotates, even when the fluid contains impurities such as iron powder and dust, the impurities are deposited on the end surface of the plunger or the plunger and the plunger are in sliding contact with each other. This impurity does not adhere to the inner wall surface of the valve chamber, and this impurity can be positively discharged from the valve chamber. Therefore, it is possible to prevent a decrease in the stroke amount of the plunger and deterioration of the movement of the plunger due to the impurities, and it is possible to prevent deterioration of the controllability of the solenoid valve.

Further, since the flow passage is constituted by a plurality of grooves formed on the side surface of the plunger, the plunger can obtain a large rotational force, so that the accumulation and adhesion of impurities can be more surely performed. Can be prevented.
By ensuring a large flow rate of the fluid, the impurities can be easily discharged.

Further, the groove is provided with a first flow groove formed on one side of the plunger and a second flow groove formed on the other side of the plunger.
With respect to the one configured by the above-mentioned flow groove, by increasing the passage speed of the fluid passing through both flow grooves, the flow rate of a large amount of fluid can be secured and the impurities can be discharged more easily. In addition, since a stable rotating force can be obtained, the plunger can be stably rotated.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view showing the plunger of the same embodiment.

FIG. 3 is a perspective view showing a plunger of the same embodiment.

FIG. 4 is a plan view showing a plunger according to another embodiment of the present invention.

FIG. 5 is a perspective view showing a plunger of the same embodiment.

FIG. 6 is a sectional view showing a conventional solenoid valve.

FIG. 7 is an enlarged view of a portion A of FIG.

[Explanation of symbols]

 1 Solenoid Valve 9 Inflow Path 10 Seat Hole 11 Seat 18 Valve Chamber 19 Plunger 26 Side 27 Flow Channel 28 Virtual Surface 29 First Flow Groove 30 Second Flow Groove F Rotational Force

Claims (3)

[Claims] 1. A solenoid valve provided with a plunger provided slidably in a valve chamber, and a passage for allowing a fluid flowing from the front side of the plunger to flow to the rear side of the plunger. An electromagnetic valve, wherein the flow passage is formed in a spiral shape. 2. The solenoid valve according to claim 1, wherein the flow passage is formed by a plurality of grooves formed on a side surface of the plunger. 3. A first flow-through groove formed on one side of the imaginary surface and the other when the imaginary surface that bisects the plunger along the sliding direction is assumed as the groove. The solenoid valve according to claim 2, wherein the solenoid valve is constituted by a second flow groove formed on the side.