JPH02212685A - 2-position solenoid valve - Google Patents

Abstract

PURPOSE:To reduce the size and the weight of a valve, to eliminate a spacer, and to enable reliable execution of operation with high response by a method wherein the one of a core and a yoke is protruded from the end surface of the other, and the area of the end surface of the protruding one of the core and the yoke is reduced to a value lower than that of the end surface of the other. CONSTITUTION:Provided, under the non-energizing state of a solenoid coil 14, a gap between a core 12 and a plunger 16 is delta1 and a gap between a yoke 24 and the plunger 16 is delta2, a relation of delta1<delta2 is satisfied between the two gaps. Provided the area of the end surface, positioned facing the plunger 16, of the core 12 is S1 and the area of the end surface, positioned facing the plunger 16, of the yoke 24 is S2, a relation of S1/S2 is satisfied between the two areas. Since a 2-position solenoid valve 10 is formed in a manner described above, despite of the plunger 16 formed such that it is flat and has a low occupying volume and is reduced in size and weight, the plunger generates a high operation force higher than that of a cylindrical plunger and provides high response. Besides, the solenoid valve eliminates a spacer and enables reliable execution of a valve motion.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a two-position solenoid valve having a movable iron piece as a plunger.

[Prior Art] A conventionally known two-position solenoid valve is shown in Fig. 3 (
As shown in the principle explanatory diagrams A) and (B), there are two types of plunger P, one using a plate-shaped movable iron piece and the other using a cylindrical magnetic body. type of solenoid valve is utilized.

For example, the above-mentioned cylindrical two-position solenoid valve is mainly used in applications that require high-speed response.

This is because the cylindrical plunger P has a small gap with the yoke Y on its circumferential surface as shown in FIG. This is because only one air gap X between the core C and the plunger P acts as a magnetic resistance.

On the other hand, a solenoid valve whose plunger P is a movable iron piece,
This is because an air gap X exists between the plunger P and the core C, which are movable pieces of iron, and between the plunger P and the yoke Y, and the magnetic resistance is approximately doubled.

In Fig. 3, if the magnetic permeability JJ, r of the magnetic bodies such as the core C and the yoke Y is sufficiently large compared to the magnetic permeability j10 of air and the magnetic resistance of these parts is ignored, then the core C and the plunger Air gap X with P and core cross-sectional area S
are the same, and assuming that the same magnetomotive force U is applied, the attractive force F1 acting on the movable iron piece plunger P and the attractive force F2 acting on the cylindrical plunger P'c are expressed by the following equations.

That is, Fl = X F2.

Also, in any of the types of solenoid valves shown in FIGS. 3(A,) and (B), the plunger P is
If both members are in complete contact with each other when attracted to the core C, even if the excitation of the coil L is stopped, the attraction force will continue to act on the plunger P due to the influence of the residual magnetic flux of the core C and the yoke Y. There is a possibility that the plunger P does not separate from the core C, which may impede the valve action.

Therefore, conventionally, a non-magnetic spacer T is inserted between the core C or yoke Y and the plunger P to ensure a gap equivalent to the thickness of the spacer T even when the plunger P is attracted ( Special Publication No. 62-4588).

[Problems to be Solved by the Invention] As is clear from a glance at the principle explanatory diagram shown in FIG. Since it occupies a small area, it is advantageous in making it smaller and lighter. However, as described above, the movable iron piece type solenoid valve has a small suction force of the plunger P, and is not suitable for applications requiring high-speed response. That is, it is difficult for the conventional two-position solenoid valve to achieve both high-speed response and reduction in size and weight.

Furthermore, any type of two-position solenoid valve requires a spacer T, making assembly and parts management complicated.

The present invention has been made in order to solve these problems remaining with two-position solenoid valves, and provides an excellent two-position solenoid valve that is small and lightweight, does not require a spacer, and operates reliably with high responsiveness. is intended to provide.

[Means for Solving the Problems] In order to solve the above problems, the two-position solenoid valve of the present invention includes: a ring-shaped core made of a magnetic material; a coil wound around the core; a yoke made of a magnetic material that surrounds the coil and continues to one end surface of the core; a movable iron piece disposed opposite to the other end surface of the core and the yoke; a spring member that biases the movable iron piece in a direction further apart from the other to cause the movable iron piece to exhibit a first valve action; In the two-position solenoid valve that causes the movable iron piece to exhibit a second valve action by attracting the movable iron piece to the other end surface, one of the core or the yoke is made to protrude from the other end surface, and one of the protruding one The gist is that the area of the end face of the core or ball is smaller than the area of the end face of the other yoke or core.

[Function] The two-position solenoid valve of the present invention has one of the cores or yokes protruding that faces the movable iron piece, so when the movable iron piece is attracted, it comes into contact with this protruding core or yoke, and the other yoke Alternatively, a gap will exist between the core and the movable iron piece. Therefore, this void acts as if it were a spacer.

Furthermore, the yoke or core that faces the movable iron piece with a gap in between has an end surface area larger than that of the protruding core or yoke. Therefore, a strong magnetic attraction force corresponding to the area acts between the yoke or core having a large area and the movable iron piece, thereby improving the attraction and holding power of the movable iron piece.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to explain the present invention more specifically, one embodiment of the present invention will be described below with reference to the drawings.

[Embodiment] FIG. 1 is a sectional view of a two-position solenoid valve 10 according to an embodiment of the present invention, and shows a state in which a solenoid coil 14 wound around a cylindrical core 12 is not energized. In addition, as shown in the figure, the two-position solenoid valve 10 of this embodiment has a plunger 1.
6 is a type that uses a disc-shaped movable iron piece.

A first flow path 12a for the hydraulic fluid is provided on the central axis of the core 12, and a valve seat 1 is fitted approximately in the center of the first flow path 12a. On the other hand, the central axis of the plunger 16, which is disposed at a position facing the core 12, has a
A shaft 22 is loosely fitted into the first flow path 12a and has a valve body 20 at its tip. Therefore, the valve seat 18 and the valve body 20 are separated from each other or come into contact with each other due to the vertical movement of the plunger 16, and the first
The flow path 12a is conducted or cut off.

An annular yoke 24 joined to the bottom surface of the core 12 surrounds the solenoid coil 14 and faces the plunger 16 similarly to the top surface of the core 12. A ring material 26 made of a non-magnetic material is fitted onto the upper surface of the solenoid coil 14 whose side and bottom surfaces are surrounded by the core 12 and the yoke 24 as shown in FIG. In addition, this ring material 26
2 also serves as a pedestal for the coil spring 2 made of a non-magnetic material that urges the plunger 16 upward in the drawing.

Further, the base member 30 continuous with the upper end surface of the yoke 24 has a second flow path 30a formed therein, and a plunger 1
6, and is made of a non-magnetic material. Base member 30 and valve seat 1
The first =8 guide 34 and the second guide 36 are annular members having a center hole, into which the shaft 22 is loosely fitted. Therefore, the movement of the shaft 22 in the vertical direction in the drawing coincides with the axial direction of the shaft, and the sealing performance between the valve body 20 and the valve seat 18 is ensured. Note that the center hole of the second guide 36 is provided with a notch 36a that serves as a passage for the hydraulic fluid.

The two-position solenoid valve 10 of this embodiment, which is constructed from the above-mentioned members, has the following characteristic structure in the mutual relationship among the core 12, yoke 24, and plunger 16.

First, when the solenoid coil 14 is in a non-energized state (the state shown in FIG. 1), the gap between the core 12 and the plunger 16 is 81, and the gap between the yoke 24 and the plunger 16 is 82. The structure is such that the relationship δ1<δ2 is satisfied between them. In this embodiment, the relationship between rain gaps is designed to be 82=2×81.

Second, if the area of the end face of the core 12 facing the plunger 16 is Sl, and the area of the end face of the yoke 24 facing the plunger 16 is 82, then Sl < 5 between the two areas.
The configuration is such that the following relationship is satisfied. In order to simply represent this relationship, an end view of the core 12 and yoke 24 viewed from the plunger 16 side is shown in FIG. As shown in the figure, in this embodiment, the area S2 of the end face of the yoke 24 is twice the area S1 of the end face of the core 12.

In the two-position solenoid valve 10 of this embodiment configured as described above, when the solenoid coil 14 is not energized, the plunger 1 is moved by the coil spring 28 as shown in FIG.
6 is pushed upward in the drawing, and becomes stable at the position where the shaft 22 and the base member 30 abut. Therefore, the hydraulic fluid flowing from the first flow path 12a passes through the notch 36a provided in the second guide 36 and the liquid chamber 32, and enters the second flow path 30a.
flows to.

Furthermore, when the solenoid coil 14 is energized, an attractive force is generated between the plunger 16 and the core 12 and between the plunger 16 and the yoke 24, and when this attractive force exceeds the set load of the coil spring 28, the plunger 16 moves downward in the drawing. Then, the valve body 20 and the valve seat 18 come into contact with each other, and the first flow path 12a is closed. Therefore, the first flow path 12
a and the 20th flow path 30a are in a non-conducting state.

In addition to performing such basic operations as a solenoid valve, the two-position solenoid valve 10 of this embodiment generates an extremely large force during its operation as described below, and therefore the plunger 16 Demonstrates high-speed response that drives instantly.

In other words, in a two-position solenoid valve using a cylindrical plunger that has excellent high-speed response (see Fig. 3 (B)),
The facing area of the plunger and the core is the same as that of this embodiment (f
i S 1 and the gap is the same as the gap δ2 between the plunger 16 and the yoke 24 of this embodiment,
As already described, the suction force F2 acting on the plunger is expressed by the following equation.

2 δ22 On the other hand, in the two-position solenoid valve 10 of this embodiment, the core 1
2 and the plunger 16, the force Fa acting between the yoke 2 and the plunger 16
The resultant force F of the force Fb acting between 4 and the plunger 16
(=Fa+Fb) acts on the plunger 16. Here, the forces Fa and Fb are respectively expressed by the following equations.

= F2 ,', F = F a + F b = F2 = 11- In this way, the two-position solenoid valve 10 of this embodiment (accordingly, the cylindrical plunger type with the same end surface area S1 and the same magnetomotive force U) It is clear that the force F for attracting the plunger 16 is (3/2) times as large as that of the electromagnetic valve shown in FIG.

Furthermore, the two-position solenoid valve 10 of this embodiment is different from the conventional two-position solenoid valve 10.
A spacer, which is an essential component of a position solenoid valve, is not required.

That is, as shown in FIG. 1, the two-position solenoid valve 10 of this embodiment has a gap of 81, δ2 (=2·δ1) between the plunger 16 and the core 12 and between the plunger 16 and the yoke 24.
It is configured such that a gap is formed. Therefore, the plunger 16 is sucked with extremely strong force as described above, and the core 1 is
Even if you try to suck it up to the position where it contacts plunger 1,
There is still 81 (=82-81) between 6 and yoke 24.
), and the result is the same as if a spacer with a thickness of δ1 was used. Therefore, even if a large amount of residual magnetic flux is generated in the core 12 or the yoke 24, the plunger 16 will be pushed upward in the drawing by the elastic force of the coil spring 2, and the solenoid coil 14 will not be energized. can perform valve operation.

As described above, according to the two-position solenoid valve 1o of the present embodiment, the plunger 16 has a flat plate shape, occupies a small volume, is small and lightweight, and generates a larger operating force than a cylindrical plunger. Demonstrates high-speed response. Moreover, the valve operation can be performed reliably without the need for a spacer.

This simplifies the manufacturing process and parts management, making it easy to manufacture, and it can also be applied to applications where mounting capacity is limited and requires large actuation force and high-speed response.

In addition, in the two-position solenoid valve 10 of the above embodiment, in order to simplify the comparison with the conventional example and calculation, the case where the gaps δI, δ2 and the areas SL, S2 are in a simple integer multiple relationship has been explained. These values are appropriately determined in consideration of the response speed and operating force required for the two-position solenoid valve 10, as well as limitations on occupied area and weight.

Further, in this embodiment, the yoke 24 is connected to the plunger 16.
The gap between the core 12 and the core 12 is made smaller, and the opposing area is made smaller. However, the configuration is not limited to this, and the yoke 24 and plunger 1
The structure may be configured in various ways without departing from the gist of the present invention, such as by configuring the gap with 6 to be small and decreasing the opposing area.

[Effects of the Invention] As explained above, according to the two-position solenoid valve of the present invention, one of the core or the yoke is formed with a small gap with respect to the movable iron piece-shaped plunger, and the opposing area is configured to be small. The summary is what was done.

Therefore, although the plunger occupies a small volume and is compact and lightweight, it generates a strong actuation force and exhibits high-speed response. Moreover, the spacer that was conventionally necessary to ensure valve operation is not required, the structure is simplified, and manufacturing is simple and inexpensive.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a two-position solenoid valve that is an embodiment of the present invention, Fig. 2 is an explanatory diagram of the end surface area of its core and yoke, and Figs. 3 (A) and (B) are a conventional two-position solenoid valve. A configuration explanatory diagram of a solenoid valve is shown.

Claims (1)

[Scope of Claims] 1. An axial core made of a magnetic material, a coil wound around the core, and a yoke made of a magnetic material surrounding the coil and continuous to one end surface of the core. and,
a movable iron piece disposed to face the other end face of the core and the yoke; and a spring member that biases the movable iron piece in a direction away from the other end face to cause the movable iron piece to perform a first valve action. and a two-position electromagnetic device that attracts the movable iron piece to the other end face against the elastic force of the spring member when the coil is energized, and causes the movable iron piece to perform a second valve action. In the valve, one of the core or yoke is made to protrude from the other end face, and the area of the end face of the protruding one core or yoke is formed to be smaller than the area of the end face of the other yoke or core. A two-position solenoid valve characterized by: