JP2001006925A - Two-directional proportional solenoid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-directional proportional solenoid capable of increasing attracting force by improving efficiency of flow of magnetic flux. SOLUTION: A solenoid S is constituted of a coil assembly 1 and a tube assembly 2. The coil assembly 1 has two coils 12A, 12B and a yoke 13 arranged between both of the coils 12. The tube assembly 2 has two fixed cores 21A, 21B which face with each other, a pipe 22 connecting both of the fixed cores 21, and a movable core 24 sliding on the inner peripheral surface of the pipe 22. In the pipe 22, magnetic parts 22a, 22b, 22c are formed in both end parts and an intermediate part, and nonmagnetic parts 22d, 22e are formed in the parts between the respective magnetic parts. The magnetic part 22a and the nonmagnetic part 22d, and the magnetic part 22b and the nonmagnetic part 22e are engaged with a tapered surface 23, respectively, and form a horizontal characteristic part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-way proportional solenoid in which a movable iron core is arranged so as to be attracted to two fixed iron cores.

[0002]

2. Description of the Related Art In general, a solenoid includes a movable core and a fixed core, and the movable core is attracted to the fixed core side by exciting a coil. When the excitation of the coil is released, the movable iron core attracted by the return spring is returned. When the distal end side of the movable iron core is connected to the spool of the valve body, it can be used as a solenoid valve.
However, in this solenoid valve, it is difficult to balance the suction force of the solenoid with the load of the return spring because the suction force with respect to the stroke of the supplied current appears as a curve of a characteristic in which the suction force increases in the suction side. Therefore, the movable iron core cannot be stopped at a position in the middle of the stroke.

[0003] To solve this problem, a proportional solenoid is used. The proportional solenoid can take a balance position with the load of the return spring, and forms a horizontal characteristic portion such that the suction force is constant over substantially the entire stroke at the controlled current value. Thereby, the attraction force is increased in proportion to the rising current. This horizontal characteristic portion is usually formed by engaging a non-magnetic portion and a magnetic portion with a taper surface on a pipe engaged with a fixed iron core and fitted with a movable iron core. Therefore, by controlling the current, the position of the balance with the return spring can be continuously changed and adjusted to an arbitrary position, so that the position of the spool in the valve body can be adjusted, Position accuracy can be maintained. As a result, the flow rate or pressure of the fluid flowing through the valve can be accurately maintained at the set stroke.

On the other hand, the movable core is moved to the fixed core side by the excitation of the coil, and is returned by an external spring when the excitation of the coil is released. This spring is usually provided by a spring mounted on the other solenoid in the case of a double solenoid valve. However, in the case of a single solenoid valve, two coils and two fixed iron cores are mounted in one solenoid, and the movable iron core is held at an intermediate position by a spring at a normal position of the movable iron core. When moving in any direction, the movable core is attracted and moved by the excitation of each coil. This is generally called a two-way solenoid. A two-way solenoid used as a proportional solenoid is called a two-way proportional solenoid.

Conventionally, as shown in FIG. 3, a two-way proportional solenoid S2 has a coil assembly 51 having two coils 52 arranged concentrically with a yoke 53 interposed therebetween, and inserted into the coil assembly 51. Tube Assy 55
And is configured. The fixed core 56 constituting the tube assembly 55 has a flange portion 56a at its base, supports the coil 52 on the side surface, and has a fitting hole 56b for fitting the outer peripheral surface of the movable core at the inner peripheral surface of the distal end portion. A tapered surface 56c is formed so that the outer peripheral surface of the distal end portion is tapered. The two fixed iron cores 56 are arranged so that their tip portions face each other, and a non-magnetic pipe 57 is arranged so as to connect the outer peripheral surfaces of the tip portions of the two fixed iron cores 56.

On the other hand, the movable iron core 58 is connected to one of the fixed iron cores 5.
6, a long pin 60 that slides in the bearing 59 mounted on the shaft portion of the shaft 6 and projects through the bearing 59 mounted on the shaft portion of the other fixed iron core 56 and projects toward the valve body. The fitting portion 56b of the fixed iron core 56 having two outer peripheral surfaces
It is formed to move inside. One coil 52
The magnetic flux generated by the excitation of flows through one of the fixed iron core 56 and the movable iron core 58. At this time, fixed core 5
6 forms a horizontal characteristic portion as a proportional solenoid.

[0007]

However, the conventional two-way proportional solenoid S2 has a tapered surface 56 of the fixed iron core 56.
Since c is formed so as to taper from the inner peripheral surface of the pipe 57 toward the movable iron core 58 side, the gap H of the non-magnetic portion between the outer peripheral surface of the pipe 57 and the outer peripheral surface of the movable iron core 58 is large. Had been formed. That is, since the distance between the yoke 53 and the movable iron core 58 in which the pipe 57 is fitted to the outer peripheral surface is large, the magnetic flux flowing from the movable iron core 58 to the yoke 53 is lost between them, and the efficiency is reduced, and the predetermined attracting force is reduced. Can not be demonstrated.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a two-way proportional solenoid that improves the efficiency of the flow of generated magnetic flux and improves the attraction force.

[0009]

A two-way proportional solenoid according to the present invention has the following configuration to solve the above-mentioned problems. That is, a coil assembly having two coils arranged concentrically and a yoke arranged between the coils, and a tube assembly inserted into the coil assembly, wherein the tube assembly is A two-way proportional solenoid including two fixed iron cores disposed at opposing positions, a pipe engaging and connecting the fixed iron cores, and a movable core moving inside the pipe. The pipe is formed having a magnetic part and a non-magnetic part, and the magnetic part is provided at least between the movable core and the yoke.

Preferably, the magnetic portion formed in the pipe is disposed at both ends and an intermediate portion of the pipe, and a magnetic portion disposed at both ends and a magnetic portion disposed at the intermediate portion are provided. A non-magnetic portion may be provided between the two ends, and the magnetic portions provided at both ends and the adjacent non-magnetic portion may be engaged with the respective tapered surfaces.

Further, the magnetic part formed in the pipe may be:
Disposed at an intermediate portion of the pipe, adjacent both ends of the magnetic portion are formed of a non-magnetic portion and are fitted to the fixed core, and a tapered surface is formed on an outer peripheral surface of a distal end portion of the fixed core. It may be characterized by that.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a two-way proportional solenoid (hereinafter, referred to as a solenoid) S of the first embodiment is wound around an outer peripheral surface of a hollow bobbin 11 and is coaxially arranged. Coils 12A, 12B
A coil assembly 1 formed by integrally molding resin and a hollow yoke 13 sandwiched between two coils 12A and 12B with a resin, and a tube assembly 2 mounted in the coil assembly 1. It is configured to have. The tube assembly 2 has two fixed iron cores 21A and 21B arranged at opposing positions, a pipe 22 connecting between the two fixed iron cores 21A and 21B, and a movable iron core 24 moving inside the pipe 22, One of the pins 25 inserted into the movable core 24 is connected to a spool of a solenoid valve (not shown), and the movable core 24 moves the spool back and forth. The solenoid S is known as a wet type, and for example, hydraulic pressure is circulated around the movable iron core 24. Therefore, the movable iron core 24 is configured to be connected to the two fixed iron cores 21A and 21B by the pipe 22 so that the hydraulic pressure does not leak outside.

The fixed core 21 has a flange portion 21a for supporting the side surface of the bobbin 11, a bobbin support portion 21b fitted to the inner peripheral surface of the bobbin 11, and a smaller diameter than the bobbin support portion 21b. Fitted pipe support 21
c and is formed in a stepped cylindrical shape. Further, a pin moving hole 21d through which the pin 25 of the movable iron core 24 is inserted is formed in the axial center portion of the fixed iron core 21, and a bearing 26 is mounted in the pin insertion hole 21d. Further, the end face of the fixed iron core 21 facing the movable iron core 24 has a residual magnetism prevention spacer 27.
Is mounted, and after the movable iron core 24 is attracted to the fixed iron core 21, the coil 12 can be quickly detached when returning by de-energizing the coil 12.

The pipe 22 connecting the two fixed iron cores 21A and 21B is formed thicker than the conventional pipe 22, and has a magnetic portion and a non-magnetic portion. In the first embodiment shown in FIG.
a, 22b, a magnetic portion 22c is formed at the center, and non-magnetic portions 22d, 22e are formed therebetween. Therefore, the pipes 22 are formed in five layers in which magnetic parts and non-magnetic parts are alternately arranged.

The magnetic parts 2 formed at both ends of the pipe 22
2a and 22b are pipe support portions 21c of each fixed iron core 21.
And is formed so as to be fittable so as to cover around each end of the movable iron core 24, and the nonmagnetic portions 22d and 22e
Between the fixed iron core 21 side and the movable iron core 24 side. Pipe 22
The magnetic part 22c formed at the center of the yoke 13 is formed so as to be substantially at the center of the movement of the movable iron core 24 and is fitted to the inner peripheral surface of the yoke 13. Therefore, the movable iron core 24
During the movement, the magnetic flux flowing into one of the fixed iron core 21 and the movable iron core 24 is transferred from the movable iron core 24 to the pipe 22.
Since the air flows into the yoke 13 without forming a gap through the magnetic portion 22c, the attraction force can be efficiently generated.

When the pipe 22 is formed, a groove (a non-magnetic portion in FIG. 1) having a tapered surface outward is formed at two locations with respect to a longitudinal center portion of a cylindrical body formed of a magnetic material. Then, a non-magnetic material is built up in the groove and welded. In this state, the inner peripheral surface of the cylindrical body is formed of full-length magnetic material, so the inner peripheral surface is cut until the magnetic material portion of the inner peripheral surface is removed, and the outer peripheral surface is also made of a magnetic material and a non-magnetic material. When the cutting process is performed so that the surfaces are the same, a pipe 22 as shown in FIG. 1 is formed.

The movable iron core 24 moving in the pipe 22
Any one of the magnetic parts 22 formed at both ends of the pipe 22
a, 22b so as to always move. The pin 25 is inserted through the movable core 24, one end slides in the bearing 26 in the pin insertion hole 21d of the fixed iron core 21A, and the other end passes through the pin insertion hole 21d of the fixed iron core 21B. It slides in the bearing 26 mounted in the insertion hole 21d.

The bearing 26 mounted in the pin insertion hole 21d of the fixed iron core 21 is not included in this embodiment as long as the movable iron core 24 is formed so as to slide on the inner peripheral surface of the pipe 22. Is also good. The pins 25 may be attached to the movable iron core 24 so as not to penetrate the movable iron core 24 but to protrude separately from both ends of the movable iron core 24.

In the solenoid S configured as described above, when the coil 12 is not excited, the movable iron core 24 is connected to the pipe 22 by an external return spring (not shown).
Is located at the approximate center. When one coil 12, for example, the upper coil 12A in FIG. 1 is excited, the magnetic flux flows from the coil 12A to the upper fixed core 21A and the movable core 24, and the magnetic flux formed from the movable core 24 to the center of the pipe 22 is formed. By forming a loop flowing through the portion 22c and flowing to the yoke 13, the movable iron core 24 is attracted and moved to the fixed iron core 21A. While the movable iron core 24 is attracted and moved from the center position of the pipe 22 to the fixed iron core 21A, the movable iron core 24 and the magnetic portion 22c in the middle part of the pipe 22 are always in a fitted state and are adjacent to each other. Since almost no gap is formed between the nonmagnetic portions, the generated magnetic flux efficiently flows from the movable iron core 24 to the yoke 13 and does not lower the attraction force. And the coil 12A
Is released, the movable iron core 24 is moved to the center of the pipe 22 again by an external return spring (not shown).

When the other coil (the lower coil in FIG. 1) 12B is excited, the magnetic flux flows from the coil 12B to the lower fixed core 21B and the movable core 24,
The movable core 24 is attracted and moved to the fixed iron core 21B by forming a loop flowing from the base member 4 to the yoke 13 through the magnetic part 22c formed at the center of the pipe 22.
The movable iron core 24 moves from the center of the pipe 22 to the fixed iron core 21.
The magnetic flux is absorbed by the movable iron core 2 in the same manner as described above.
4 to the yoke 13 efficiently.
The adsorption power to B does not decrease. And coil 1
When the excitation of 2B is released, the movable iron core 24 is moved to the center of the pipe 22 by the return spring as described above.

In the solenoid S1 of the second embodiment shown in FIG. 2, the coil assembly 3 includes the bobbin 3 as in FIG.
1, and two coils 32A, 3 wound around the bobbin 31
2B and a yoke 33 formed between the two coils 32A and 32B, the fixed core 41, the pipe 42, and the movable core 44 constituting the tube assembly 4 are:
It is changed as follows.

The fixed iron core 41 has a flange portion 41a for supporting the side surface of the bobbin 31, a bobbin support portion 41b fitted to the bobbin 31, and a pipe formed to have a smaller diameter than the bobbin support portion 41b and fitted to the inner peripheral surface of the pipe 42. Supporting portion 41c and tapered surface 41d formed at the tip of pipe supporting portion 41c
And a movable iron core 44 formed inside the pipe support portion 41c.
Is formed having an inner moving surface 41e on which the inner surface moves. Further, a pin insertion hole 41f through which the pin 45 of the movable iron core 44 is inserted is formed, and a bearing 47 is mounted in the pin insertion hole 41f. The inner moving surface 41 of the fixed iron core 41
A residual magnetism prevention spacer 47 is attached to e.

The pipe 42 has a magnetic portion 42a at the center and non-magnetic portions 42b and 42c on both sides of the magnetic portion 42a. When the pipe 42 is formed, the end faces of the magnetic part 42a of the cylindrical body and the nonmagnetic parts 42b and 42c of the cylindrical body are pressed against each other.

The movable iron core 44 has a large-diameter iron core 44a formed in the center and moving in the pipe 42, and a small-diameter iron core 4 formed on both sides and moving on the inner moving surface 41e of the fixed iron core.
4b, and an elongate pin 45
Is inserted. The large-diameter core portion 44a that moves in the pipe 42 is formed so as to always be adjacent to the magnetic portion 42a of the pipe 42.

The operation of the solenoid S1 of this embodiment is substantially the same as the operation of the solenoid S of the first embodiment, and a detailed description thereof will be omitted. When any of the coils 32A (for example, the upper coil in FIG. 2) is excited, the movable core 44
Moves by suction toward the fixed iron core 41A. Movable iron core 4
When the member 4 moves, the large diameter portion 44a always moves in the magnetic portion 42a of the pipe 42, so that the magnetic flux flows from the movable iron core 44 to the yoke 33 without a gap. it can.

It should be noted that the two-way proportional solenoid of the present invention is not limited to the above-described configuration, but may be any as long as the magnetic portion of the pipe is formed between the yoke and the movable iron core.
The configuration of the pipe or the fixed iron core may be other than the above.

[0027]

According to the first aspect of the present invention, as described above,
The two-way proportional solenoid includes a coil assembly having two coils arranged concentrically and a yoke arranged between the coils, and a tube assembly inserted into the coil assembly. A fixed core disposed at a position facing the tube assembly, a pipe engaging and connecting the fixed cores, and a movable core moving in the pipe. Wherein the pipe is formed having a magnetic portion and a non-magnetic portion, and the magnetic portion is disposed at least between the movable iron core and the yoke. When the movable core is attracted to one of the fixed cores by excitation of one of the coils, the movable core constantly moves in the magnetic part of the pipe, so that the magnetic flux generated by the excitation of the coil causes the movable core and the magnetic core to move. It can flow without producing a gap with the yoke. Therefore, a stable operation of the proportional solenoid can be performed without reducing the attraction force.

According to a second aspect of the present invention, there is provided a two-way proportional solenoid, wherein the magnetic portion formed on the pipe is disposed at both ends and an intermediate portion of the pipe, and the magnetic portion disposed at both ends is provided at an intermediate position between the magnetic portions. A non-magnetic portion is disposed between the magnetic portion and the magnetic portion disposed on the portion, and the magnetic portions disposed on both ends and the adjacent non-magnetic portion are respectively engaged with tapered surfaces. 2. The movable core according to claim 1, wherein the movable core moves within a magnetic part provided at an intermediate portion of the pipe, and both ends of the movable core also move within magnetic parts provided at both ends of the pipe. 3. The same effect as the two-way proportional solenoid is exerted, and the horizontal characteristic portion as the proportional solenoid can be formed in the pipe by the engagement of the magnetic portion and the non-magnetic portion in the pipe on the tapered surface. The fixed iron core can be manufactured with a simple configuration, and the cost can be reduced.
Furthermore, if the movable iron core is formed so as to slide and guide on the inner peripheral surface of the pipe, it is possible to eliminate a bearing that slides and guides the pin of the movable iron core.

According to a third aspect of the present invention, in the two-way proportional solenoid, the magnetic portion formed on the pipe is disposed at an intermediate portion of the pipe, and both ends adjacent to the magnetic portion are formed by non-magnetic portions. The fixed core is fitted to the fixed core, and an inner end of the fixed core has a tapered surface. 2. The pipe according to claim 1, wherein the pipe always moves in a magnetic part in the pipe by excitation of one of the coils.
An effect similar to that of the directional proportional solenoid can be exerted.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing one embodiment of a two-way proportional solenoid of the present invention.

FIG. 2 is a front sectional view showing a two-way proportional solenoid according to another embodiment of the present invention.

FIG. 3 is a front sectional view showing a conventional two-way proportional solenoid.

[Explanation of symbols]

 S, S1 solenoid 1, 3, coil assembly 2, 4, tube assembly 12, 32, coil 13, 33 yoke 21, 41, fixed iron core 22, 42, pipe 22a, 22b, 22c, 42a, magnetic part 22d, 22e, 42b, 42c: non-magnetic portion 23: tapered surface 41d: tapered surface 24, 44: movable core

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroshi Goto 6-10 Ushimaki-cho, Mizuho-ku, Nagoya-shi, Aichi F-term (reference) in Sanmei Electric Co., Ltd. 5E048 AA08 AC08 AD03 CB07

Claims (3)

[Claims] A coil assembly having two coils arranged concentrically and a yoke disposed between the coils, and a tube assembly inserted into the coil assembly; Two fixed cores disposed at positions where the tube assemblies face each other, a pipe engaging and connecting the fixed cores, and a movable core moving in the pipe;
A two-way proportional solenoid configured with: wherein the pipe is formed having a magnetic part and a non-magnetic part,
The two-way proportional solenoid, wherein the magnetic part is disposed at least between the movable iron core and the yoke. 2. A magnetic part formed on the pipe is disposed at both ends and an intermediate part of the pipe, and is provided between a magnetic part disposed at both ends and a magnetic part disposed at an intermediate part. 2. The two-way proportional element according to claim 1, wherein a non-magnetic portion is disposed on the first portion, and the magnetic portion disposed at both ends and the adjacent non-magnetic portion are respectively engaged by tapered surfaces. solenoid. 3. A magnetic part formed in the pipe is provided at an intermediate part of the pipe, and both ends adjacent to the magnetic part are formed of non-magnetic parts and fitted to the fixed iron core, 2. The two-way proportional solenoid according to claim 1, wherein a tapered surface is formed on an outer peripheral surface of a distal end portion of the fixed iron core.