JPH11141714A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dissolve a problem such that restriction is imposed when a solenoid valve is mounted on a vehicle since it is necessary for opening a delivery port upward and it is difficult to form the solenoid valve in a small size, and also a constitution is complicated since a specific drain port connected to the delivery port is necessary. SOLUTION: Two oil reservoir chambers 42, 43 for circulating hydraulic oil by displacement of a plunger 38 are formed on both end parts of an electromagnetic part 30, an annular groove 45 is formed so as to enclose one of two oil reservoir chambers 42, 43, the annular groove 45 and the oil reservoir chambers 42, 43 are communicated with each other through a first passage 46 opened to a lower position of the oil reservoir chamber, and the annular groove 45 is opened upward through a second passage 47 opened to the upper position of the annular groove 45.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve capable of constantly storing hydraulic oil for damping in an electromagnetic portion.

[0002]

2. Description of the Related Art A plunger is electromagnetically attracted in accordance with a current value applied to a coil of an electromagnetic section, and a spool of a spool valve section is slid to control a supply port, a control port, and a passage between a control port and a discharge port. Solenoid valves that change the pressure of hydraulic oil flowing to a control port are well known. When this solenoid valve is used, for example, for hydraulic control of an automatic transmission, in many cases, as shown in FIG.
The solenoid valve is mounted on the valve body 3 of the vehicle in a horizontal state in which the spool valve portion 1 and the electromagnetic portion 2 are horizontal and at a position above the oil level of a tank for storing hydraulic oil. I have.

In this type of solenoid valve, it is necessary to constantly store hydraulic oil in the electromagnetic portion in order to provide damping to the operation of the plunger 4 of the electromagnetic portion, and furthermore, fine foreign matters mixed in the hydraulic oil. However, it is necessary to prevent the sliding action of the plunger 4 from entering the sliding portion of the plunger 4 due to the pump action accompanying the operation of the plunger 4. For this reason, conventionally,
Oil sump chambers 5 (one not shown) are provided on both sides of the plunger 4 of the electromagnetic unit 2, and a drain port 6 is opened below the oil sump chamber 5 on the spool valve unit 1 side, and the drain port 6 is connected to the spool valve unit. It is connected via a communication passage 8 below a discharge port 7 which is opened above 1.

[0004] In this way, the hydraulic oil is always stored in the oil reservoir 5 located below the opening of the discharge port 7, and foreign matters mixed in the hydraulic oil are positioned below the oil reservoir 5. Plunger 4
To prevent it from entering the sliding part.

[0005]

In the above-mentioned conventional solenoid valve, in order to store the working oil in the oil sump chamber 5,
Since the discharge port 7 must be provided upward, there is a case where there is a restriction in mounting on the vehicle, and since the drain port 6 needs to be connected to the upward discharge port 7 through the communication passage 8, the configuration is complicated. At the same time, there is a problem that the total length of the solenoid valve is increased by the addition of the drain port 6, which hinders miniaturization.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and can reduce the size and simplification of an electromagnetic valve, provide damping to the operation of a plunger, and slide the plunger. It is an object of the present invention to provide a solenoid valve in which foreign matter does not enter the moving part.

[0007]

According to the first aspect of the present invention, there is provided a supply port, a discharge port, a control port disposed between the supply port and the discharge port, and the spool is slidable. The spool valve portion is fitted and an electromagnetic portion that displaces a plunger engaged with one end of the spool by an electromagnetic attraction force. The spool valve portion and each end of the electromagnetic portion are joined together, and the electromagnetic attraction force is applied. In the solenoid valve which slides the spool by the displacement of the plunger to control the flow path between the supply port and the control port and between the control port and the discharge port to control the pressure of the hydraulic oil flowing through the control port, At both ends, two oil sump chambers through which hydraulic oil is exchanged by the displacement of the plunger are formed, and an annular groove is formed so as to surround one of the two oil sump chambers. And the oil sump chamber are communicated via a first passage formed at one location on the circumference, and the annular groove is opened to the outside via a second passage diametrically opposed to the first passage. It was made.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows the entire configuration of the solenoid valve, and FIG. 2 shows a cross section taken along line AA of FIG. The solenoid valve has a spool valve section 10
And an electromagnetic unit 30, and the spool valve unit 10
The end faces of the valve sleeve 11 and the core 31 of the electromagnetic section 30 are coupled to each other on the same axis, so that the spool valve section 10 can be operated by the electromagnetic section 30.

A spool hole 12 is formed in a valve sleeve 11 of the spool valve section 10, and a spool 13 is fitted into the spool hole 12 so as to be slidable in the axial direction. At one end of the valve sleeve 11, a cap 14 for closing the open end of the spool hole 12 is screwed, and a spring 15 for urging the spool 13 in the direction of the electromagnetic unit 30 is interposed between the cap 14 and the spool 13. Has been inserted.

The spool hole 12 has a large-diameter hole 12A and a small-diameter hole 12B, and the small-diameter hole 12B is formed on the electromagnetic section 30 side. The large-diameter hole 12A has three annular grooves 17A.
Are formed at intervals in the axial direction, and the large-diameter holes 12A
An annular groove 17B is formed at a connecting portion between the and the small diameter hole 12B. One end of each of the supply port 21, the control port 22, and the discharge port 23 is opened in the three annular grooves 17A in order from the electromagnetic unit 30 side. The valve sleeve 11 is open at the outer peripheral portion. The annular groove 17
A feedback pressure introduction hole 24 is opened in B, and this feedback pressure introduction hole 24 is communicated with the control port 22 via a communication passage, which will be described later, including a notch 25 formed on the outer periphery of the valve sleeve 11. Has become.

The large diameter hole 12A has two large diameter lands 13A and 13B formed on the spool 13, and the small diameter hole 12B has a small diameter land 13C slidably fitted therein. Opposing edges of the two large-diameter lands 13A and 13B control the opening of the supply port 21 and the discharge port 23. When the spool 13 is displaced, the supply port 21 and the discharge port 23 are controlled. Is decreased and the other is increased so as to control the pressure of the control port 22 located between the supply port 21 and the discharge port 23.

A core 31 of the electromagnetic section 30 is made of a cylindrical magnetic material, and a hollow hole 32 is formed at the axis thereof concentrically with the spool 13. A bobbin 33 is mounted on the outer periphery of the core 31, and a coil 34 is wound around the bobbin 33. A cup-shaped cover 35 is provided so as to cover the coil 34, and one end of the cup-shaped cover 35 on the side of the spool valve portion 10 is caulked, and a flange formed on a side end portion of the core 31 and the valve sleeve 11 are formed. Are integrally connected to each other in a state where the flanges formed at the side end portions are joined to each other.

A shaft portion 36 made of a non-magnetic material is slidably inserted into a hollow hole 32 of the core 31 via a bearing bush 37. The shaft portion 36 is attached to a plunger 38 made of a magnetic material.
Is loosely fitted in a through hole formed in the cover 35 with a small gap 39, and its end is supported by the center of a disk spring 40 having an outer periphery fixed to the cover 35 so as to be axially displaceable. . A yoke portion 41 formed at one end of the core 31 corresponds to the plunger 38, and the yoke portion 41 electromagnetically attracts the plunger 38 to the spool valve portion 10 side. The plunger 38
An oil reservoir chamber 42 is formed between the disk spring 40 and the disk spring 40.

The other end of the shaft portion 36 of the plunger 38 is connected to the spool hole 12 (the small-diameter hole 12) of the valve sleeve 11.
B), and comes into contact with a small-diameter end portion formed at one end of the spool 13. An oil sump chamber 43 is formed between the spool hole 12 and the small-diameter end of the spool 13 and the shaft portion 36. The oil sump chamber 43 is communicated with the oil sump chamber 42 through the cutout portion and the gap 39 of the bearing bush 37, and the oil sump chambers 4 are moved by the pump action due to the displacement of the plunger 38.
Hydraulic oil flows back and forth between 2 and 43 to impart a damping action to the operation of the plunger 38.

An exciting current is applied to the coil 34 from a power supply controller (not shown). When an exciting current is applied to the coil 34, the coil 34 generates lines of magnetic force, and forms a magnetic circuit using the core 31, the cover 35, and the plunger 38 made of a magnetic material as magnetic paths. As a result, the plunger 38 is electromagnetically attracted to the yoke portion 41 and moves in the direction of the spool valve portion 10.

An annular groove 45 is formed on the end surface of the flange portion of the valve sleeve 11 joined to the end surface of the flange portion of the core 31 so as to surround the oil sump chamber 43 as shown in detail in FIG. ing. A first passage 46 is formed radially inward at one location on the circumference of the annular groove 45, and the oil sump chamber 43 and the annular groove 45 communicate with each other via the first passage 46. I have. A second groove is provided in the annular groove 45 at a position diametrically opposed to the first passage 46.
Is formed radially outward, and the second
The passage 47 is opened near the outer periphery of the flange portion of the valve sleeve 11. The above-described annular groove 45 and the first and second passages 46 and 47 are formed by die-casting the valve sleeve 11.

The solenoid valve having the above configuration is installed laterally by fitting the valve sleeve 11 of the spool valve portion 10 into a valve body 50 of a vehicle having a horizontal hole formed above the oil level. . At this time, the solenoid valve is mounted such that the first passage 46 is located below and the second passage 47 is located above. At this time, the discharge port 23 faces downward.
By fitting the valve sleeve 11 to the valve body 50, the inner peripheral surface of the horizontal hole of the valve body 50 and the valve sleeve 11
A communication passage 51 that connects the feedback pressure introduction hole 24 and the control port 22 is formed between the notch 25 and the notch 25.

The valve body 50 is provided with a valve sleeve 11.
A supply passage 52, a control passage 53, and a discharge passage 54 are formed to be connected to the supply port 21, the control port 22, and the discharge port 23, respectively. The supply passage 52 is a hydraulic oil supply source, and the control passage 53 is a hydraulic control. The discharge passage 54 is connected to the equipment, and the discharge passage 54 is opened on the oil level of a tank (not shown).

In FIG. 1, reference numeral 60 denotes a drain passage for draining a spring chamber in which the spring 15 is housed, and reference numeral 61 denotes a closing plate for closing one end of the cover 35. Next, the operation in the above configuration will be described. Coil 34 of electromagnetic unit 30
When the exciting current is not supplied to the
5, the spool 13 and the plunger 38 are positioned on the electromagnetic unit 30 side (the left side in the figure), so that the opposed edges of the two large-diameter lands 13A and 13B of the spool 13 And the opening of the discharge port 23 is reduced. Therefore, the control port 22
Is maintained at the highest control pressure.

When an exciting current is applied to the coil 34 of the electromagnetic section 30, an electromagnetic attractive force corresponding to the magnitude of the exciting current acts between the yoke section 41 and the plunger 38, and the spool 13 is moved together with the plunger 38 by a spring. 15 is displaced against the spring force. As a result, the opening degree of the supply port 21 is reduced and the opening degree of the discharge port 23 is increased, so that the pressure of the control port 22 is reduced as shown in FIG.
The control pressure is lowered to a control pressure corresponding to the exciting current supplied to the motor 4. The control pressure is introduced into the annular groove 17B from the control port 22 via the communication path 51 and the feedback pressure introduction hole 24, and acts on each end face of the large-diameter land portion 33A and the small-diameter land portion 33C of the spool 13. Thereby, the spool 1
In 3, the hydraulic thrust of the area difference between the large-diameter land portion 33 </ b> A and the small-diameter land portion 33 </ b> C is applied to the side opposing the spring 15 so that the control pressure becomes a pressure corresponding to the exciting current supplied to the coil 34. Perform feedback control.

By the way, the plunger 3 by the electromagnetic attraction force
At the time of operation 8 and when the plunger 38 is returned by the spring 15, the plunger 38 is stably displaced by the damping action of the working oil filled in the oil sump chambers 42 and 43. That is, the hydraulic oil filled in the oil sump chambers 42 and 43 travels between the two oil sump chambers 42 and 43 via the bearing bush 37 and the gap 39 by the pumping action due to the displacement of the plunger 38, and the operation at that time is performed. Due to the viscous action of the oil, the operation of the plunger 38 is damped.

The hydraulic oil introduced from the feedback pressure introducing hole 24 into the annular groove 17B leaks from the fitting gap between the small diameter hole 12B of the valve sleeve 11 and the small diameter land 13C and is supplied into the oil sump chamber 43. You. Hydraulic oil filled in the oil sump chamber 43 is supplied to the first oil chamber opened below the oil sump chamber 43.
The valve sleeve 11 reaches the annular groove 45 from the passage 46 of the valve sleeve 11 through a second passage 47 opened above the annular groove 45.
Is drained from above the flange. Further, the foreign matter mixed in the hydraulic oil stays at the bottom of the annular groove 45, so that the foreign matter does not enter the sliding portion of the plunger 38 even by the pumping operation accompanying the operation of the plunger 38.

According to the above-described embodiment, the oil sump chamber 4
3 is opened to the upper outside through the first passage 46, the annular groove 45, and the second passage 47 formed in the joint surface between the valve sleeve 11 and the core 31, so that the total length of the solenoid valve is increased. In addition, the configuration can be simplified, and the direction of the discharge port 23 is not limited to the upward direction or the downward direction.

In addition, even when the supply of the hydraulic oil to the solenoid valve is stopped, the hydraulic oil can be kept in the oil sump chambers 42 and 43, so that the damping effect of the plunger 38 can be fully exhibited. In addition, it is possible to reliably prevent foreign matters mixed in the hydraulic oil from entering the sliding portion of the plunger 38.

[0025]

As described above, according to the present invention, two oil sump chambers are formed at both ends of the electromagnetic section to allow hydraulic oil to flow back and forth by the displacement of the plunger, and one of the two oil sump chambers is formed. Is formed so as to surround the annular groove, and the annular groove communicates with the oil reservoir via a first passage formed at one location on the circumference, and the annular groove is diametrically opposed to the first passage. Since it is configured to be opened to the outside via the second passage, the spool valve portion and the electromagnetic portion are connected to each other by opening the first passage at a position below the oil sump chamber and forming the second passage in the annular groove. By arranging it laterally so as to open to the upper position, it is possible to keep holding the hydraulic oil in the oil sump chamber and prevent foreign matters mixed in the hydraulic oil from entering the sliding portion of the plunger. Become like

Therefore, unlike the related art, the direction of the discharge port does not need to be directed upward, so that there is no restriction on mounting on the vehicle, and the structure can be simplified.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a solenoid valve according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a diagram showing hydraulic characteristics of the solenoid valve shown in FIG. 1;

FIG. 4 is an overall configuration diagram of a conventional solenoid valve.

[Explanation of symbols]

 Reference Signs List 10 spool valve portion 11 valve sleeve 13 spool 21 supply port 22 control port 23 discharge port 30 electromagnetic portion 31 core 34 coil 38 plunger 42, 43 oil reservoir chamber 45 annular groove 46, 47 passage

Claims (3)

[Claims] A supply port, a discharge port, and a control port disposed between the supply port and the discharge port;
A spool valve portion in which a spool is slidably inserted, and an electromagnetic portion that displaces a plunger engaged with one end of the spool by an electromagnetic attraction force, and these spool valve portions and the respective ends of the electromagnetic portion are joined. An electromagnetic valve for controlling the pressure of hydraulic oil flowing through the control port by controlling the flow path between the supply port and the control port and between the control port and the discharge port by sliding the spool by the displacement of the plunger due to the electromagnetic attraction force. In each of the two ends of the electromagnetic portion, an oil sump chamber in which hydraulic oil flows back and forth by the displacement of the plunger is formed, and an annular groove is formed so as to surround one of the oil sump chambers. Are communicated via a first passage formed at one location on the circumference, and the annular groove is opened to the outside via a second passage diametrically opposed to the first passage. Do Solenoid valve. 2. The method according to claim 2, wherein the first passage is opened at a position below an oil reservoir and the second passage is connected to the spool valve and the electromagnetic unit.
2. The solenoid valve according to claim 1, wherein said passage is installed laterally so that said passage is opened above said annular groove. 3. The spool according to claim 2, wherein the annular groove is formed between the joining surfaces of the spool valve portion and the electromagnetic portion, and the second passage is opened to the outside from above between the joining surfaces. solenoid valve.