JP2580896Y2 - solenoid valve - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an inner housing having a non-magnetic portion surrounded by a coil at an intermediate portion and having a fixed core at one end, and being connected to the inner housing on both sides of the non-magnetic portion. An outer housing that covers the coil forms a housing, and a movable core that is spring-biased in a direction away from the fixed core is housed in the inner housing so as to be able to approach and separate from the fixed core. The present invention relates to a solenoid valve having a valve mechanism formed by the inner housing.

[0002]

2. Description of the Related Art Conventionally, such an electromagnetic valve is known, for example, from Japanese Utility Model Laid-Open No. 63-163379.

[0003]

The movable core is generally formed of a ferromagnetic material. However, in the above-described conventional solenoid valve, the outer surface of the movable core formed entirely of a ferromagnetic material is made of a magnetic material. The inner surface of the inner housing made of a material is slid in contact with the inner surface of the inner core, and the valve mechanism is formed between the outer surface of the movable core and the inner surface of the inner housing. However, since the ferromagnetic material is relatively soft, the movable core is worn in a relatively short time at a portion which is in sliding contact with the inner surface of the inner housing to constitute a valve mechanism, and there is a problem in durability.

[0004] The present invention has been made in view of such circumstances, and has as its object to provide an electromagnetic valve capable of improving the durability of a movable core.

[0005]

In order to achieve the above object, according to the present invention, a movable core formed of a ferromagnetic material with one end facing a fixed core is provided with a movable core. A sleeve made of a harder material and slidingly contacting the inner housing is coaxially fixed, and a valve mechanism is formed between the sleeve and the inner housing.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the sleeve is made of a non-magnetic material.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIGS. 1 and 2 show a first embodiment of the present invention. FIG. 1 is a sectional view of a normally closed solenoid valve, and FIG. 2 is a sectional view corresponding to FIG. 1 in an operating state. .

First, in FIG. 1, a housing 10 of the normally closed solenoid valve comprises an inner housing 11 and an outer housing 12. Inner housing 1
Reference numeral 1 denotes a non-magnetic portion 1 formed of a non-magnetic material in a cylindrical shape.
3 is provided with a fixed core 14 made of a magnetic material at one end and a first yoke portion 15 formed in a bottomed cylindrical shape, and the non-magnetic portion 13 is provided with a first yoke portion 15.
The fixed core 14 is fitted into the non-magnetic portion 13. Moreover, a seal member 16 that contacts the inner surface of the non-magnetic portion 13 is mounted on the outer surface of the fixed core 14.

The non-magnetic portion 13 is surrounded by a coil 18 wound around a bobbin 17. Outer housings 12 covering the coil 18 are connected to the inner housing 11 on both sides of the non-magnetic portion 13. You. The outer housing 12 is integrally connected to the fixed core 14 and extends radially outward from the fixed core 14;
A cylindrical third yoke portion 20 integrally connected to the outer peripheral end of the second yoke portion 19; and a radially outer portion of the first yoke portion 15 that is integrally connected to the first yoke portion 15 4th yoke part 21 overhanging
The outer peripheral end of the fourth yoke portion 21 has a third
The yoke part 20 is joined. Thus, the outer housing 12 holds the coil 18 between the second and fourth yoke portions 19 and 21, and forms the coil 18 with the third yoke portion 20.
Is connected to the inner housing 11 so as to surround the inner housing 11.

By the way, in the housing 10,
Fixed core 14, second yoke 19 and third yoke 20,
The first yoke portion 15 and the fourth yoke portion 21 are formed of a magnetic material such as free-cutting steel subjected to surface carburizing.

In the inner housing 11,
Between the fixed core 14 and the first yoke portion 15 working chamber 22 is formed, housed movable core 23 ₁ is in the working chamber 22 facing the fixed core 14 as allow approach to and separate from movement relative to the fixed core 14 Is done.

[0013] movable core 23 ₁ is formed into a cylindrical shape by a ferromagnetic material, such as SUY (electromagnetic soft iron). Thus, the movable core 23 ₁ is provided inside one axial end of the movable core 23 _1.
A sleeve 24 made of a magnetic material harder than ₁ , for example, SUJ (high carbon chromium bearing steel) is coaxially fixed by, for example, press fitting. Also in the other axial end side of the movable core 23 _1, the flange portion 27 forming a flow hole 26 at the inner periphery is integrally formed.

On the other hand, a small-diameter protrusion 28 coaxially extending into the working chamber 22 is coaxially protruded from the fixed core 14.
And the tip of the projecting portion 28, the flange portion 27 in the movable core 23 ₁
A return spring 29 is contracted between them. This return spring 2
By the spring force of 9, the movable core 23 ₁ will be spring-biased in a direction away from the fixed core 14.

[0015] The projection 28 Thus is what is slidably fitted in a sleeve 24 fixed to the movable core 23 _1, a valve in the outer surface and the inner surface of the sleeve 24 of the projecting portion 28 mechanism 30 ₁ is configured. The valve mechanism 30 _1, protrusions 2
An annular groove 31 provided in the 8 outer surface of, and conditions for communicating in the working chamber 22, which switches between a state of blocking the working chamber 22 according to the movement of the sleeve 24 i.e. the movable core 23 _1, the fixed core 14 Is provided with a connection hole 32 communicating with the annular groove 31, and the first yoke portion 15 is provided with a connection hole 33 communicating with the working chamber 22.

[0016] The sleeve 24, a plurality of flow holes for facilitating movement of the movable core 23 ₁ to allow the fluid in the working chamber 22 during movement of the sleeve 24 i.e. the movable core 23 ₁ flows 34 are drilled. Further, a spacer 35 formed of a nonmagnetic material in a ring shape surrounding the base of the protrusion 28 is provided with the fixed core 14 and the sleeve 2.
The spacer 35 prevents the movable core 23 from directly contacting the fixed core 14.

[0017] Next, to explain the action of this embodiment, in the state where the degaussing coil 18, by the spring force of the movable core 23 ₁ is return spring 29, as shown in Figure 1, the spaced apart from the stationary core 14 located contact with the 1 yoke portion 15, closed in this state, in a state where the annular groove 31 by a sleeve 24 of the movable core 23 ₁ is blocked and the working chamber 22, which during the connection holes 32 and 33 is cut off It is in a state.

[0018] Upon energizing the coil 18, as shown in Figure 2, is attracted to the fixed core 14 side against the spring force of the movable core 23 ₁ is return spring 29, annular groove 31 is movable core 23 ₁
It is in a state of communicating with the working chamber 22 via the inside. That is, the valve is in an open state where the connection holes 32 and 33 communicate with each other.

The movable core 23 ₁ Degaussing coil 18 in this state, becomes a closed back again to the state of FIG. 1, the action of this time, the movable core 23 ₁ is the spacer 35 by the excitation state of the coil 18 since no direct contact with the fixed core 14 by not the movement of the valve closing direction of the movable core 23 ₁ by the residual magnetism is not smooth, the movable core 23 ₁ is to return to the good response closed position Become.

By the way, in such a normally closed solenoid valve, the valve mechanism 30 _1, and the outer surface of the projecting portion 28 projecting coaxially, the projecting portion 28 was slidably fitted into the fixed core 14 Te is intended to be formed between the inner surface of the sleeve 24 fixed to the movable core 23 _1, since it is possible to configure the valve mechanism 30 ₁ in a position substantially corresponding to the coil 18, the inner housing 11 The shaft length can be set relatively short, so that the entire normally closed solenoid valve can be made compact.

[0021] Moreover the sliding contact with the projection 28 is a sleeve 24 made of relatively hard material, while maintaining the magnetic properties of the movable core 23 ₁ made of a ferromagnetic material, protrusions 2
Wear due to sliding contact with No. 8 can be suppressed as much as possible, which can contribute to improvement in durability.

FIG. 3 shows a modification of the above embodiment. A retaining ring 36 is fitted to the other axial end of the movable core 23 ₁ ′, and a taper is provided between the retaining ring 36 and the projection 28. The return spring 29 'formed in the shape of a circle may be contracted.

FIGS. 4 and 5 show a second embodiment of the present invention, in which parts corresponding to those of the above embodiment are denoted by the same reference numerals.

[0024] the working chamber 22 in the inner housing 11, _second movable core 23 is accommodated as possible the approach to and separate from movement relative to the fixed core 14. This movable core 23 ₂
Magnetic the fixed core 14 is intended to be formed into a cylindrical shape by a ferromagnetic material having a flange portion 27 that overhangs radially inward 'at the opposite end, which is harder than the movable core 23 ₂ material e.g. SUJ cylindrical sleeve 24 formed by the (high-carbon chromium bearing steel) 'is fixed by the movable core 23 ₂ example press fitting or the like. Thus, the sleeve 24 '
It is intended to be fixed to the movable core 23 within ₂ to the other end with placing the one end also inner position from one end of the movable core 23 ₂ so as to abut against the flange portion 27 '. The plurality of communication holes 34 'are provided over the entire axial length to the movable core 23 _2.

[0025] 'In the, projections 28 of fixed core 14 is slidably fitted in the outer surface of the sleeve 24 of the projections 28' the sleeve 24 the valve mechanism 30 ₂ is constituted by the inner surface of. The valve mechanism 30 _2, an annular groove 31 provided on the outer surface of the protrusion 28
And a state in which to communicate with the working chamber 22, and a state of blocking the working chamber 22 is intended to switch in response to movement of the movable core 23 _2.

[0026] That is, as shown in Figure 4, when the coil 18 is demagnetized, the movable core 23 ₂ return spring 2
9 is in contact with the first yoke portion 15 at a distance from the fixed core 14 due to the spring force of FIG. 9. In this state, the sleeve 24 ′ is located at a position where the annular groove 31 communicates with the working chamber 22. The valve 31 is in an open state in which the groove 31, that is, the connection hole 32 communicates with the connection hole 33 through the working chamber 22. The coil 18
When There is excited, as shown in Figure 5, it is attracted to the fixed core 14 side against the spring force of the movable core 23 ₂ return spring 29, a state in which the annular groove 31 is closed by the sleeve 24 'the inner surface Then, the valve is in a closed state in which the connection between the connection holes 32 and 33 is interrupted.

According to the second embodiment, the same effects as those of the first embodiment can be obtained.

In each of the above embodiments, the sleeve 2
SUJ (high carbon chromium bearing steel) which is a magnetic material was selected as a relatively hard material for forming 4,24 '.
Sleeves 24 and 2 made of non-magnetic material such as stainless steel
4 'may be formed. Then, it is possible to prevent the residual magnetism of the fixed core 14 when the coil 18 is switched from the excited state to the demagnetized state from adversely affecting the movement of the movable cores 23 ₁ , 23 ₁ ′, and 23 ₂ , and to prevent the movable core 2 from moving.
3 _1, 23 ₁ ', it is possible to improve the operational response of 23 _2.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, but may be variously modified without departing from the present invention described in the claims for utility model registration. It is possible to make design changes.

For example, the first yoke portion 15 of the inner housing 11 is formed to be long in the axial direction, and the first yoke portion 1 is formed.
The present invention can also be applied to an electromagnetic valve in which a valve mechanism is configured between the inner surface of No. 5 and the movable core.

[0031]

As described above, according to the first aspect of the present invention, the movable core formed of a ferromagnetic material with one end facing the fixed core is made of a material harder than the movable core. And a sleeve that slides on the inner housing is coaxially fixed, and a valve mechanism is configured between the sleeve and the inner housing. Therefore, the valve mechanism is configured between the sleeve and the inner housing while maintaining the magnetic characteristics of the movable core. The wear of the movable core due to the above can be suppressed and the durability can be improved.

According to the second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, since the sleeve is made of a non-magnetic material, the residual magnetism of the fixed core affects the movable core. This can be avoided, and the operation responsiveness of the movable core can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a normally closed solenoid valve according to a first embodiment.

FIG. 2 is a sectional view corresponding to FIG. 1 in an operating state.

FIG. 3 is a sectional view corresponding to FIG. 2 of a modification of the first embodiment.

FIG. 4 is a sectional view of a normally-open solenoid valve according to a second embodiment.

FIG. 5 is a sectional view corresponding to FIG. 4 in an operating state.

[Explanation of symbols]

10 Housing 11 Inner housing 12 Outer housing 13 Non-magnetic part 14 Fixed core 18 · coil 23 _1, 23 ₁ ', 23 ₂ ...... movable core 24, 24' ...... sleeve 30 _1, 30 ₂ ...... valve mechanism

Claims (2)

(57) [Scope of request for utility model registration] An inner housing (11) having a non-magnetic portion (13) surrounded by a coil (18) at an intermediate portion and having a fixed core (14) at one end, and an inner housing (11) having a non-magnetic portion (13). A housing (10) is composed of an outer housing (12) which is provided on both sides of the inner housing (11) and covers the coil (18), and is separated from the fixed core (14) in the inner housing (11). The movable core (23 ₁ , 2
3 ₁ ′, 23 ₂ ) are housed so as to be able to approach and separate from the fixed core (14), and the movable cores (23 ₁ , 23 ₁ ′,
23 ₂ ) and the inner housing (10) constitute a valve mechanism (30 ₁ , 30 ₂ ). In the solenoid valve, one end faces the fixed core (14), and the movable core ( 23 _1, 23 ₁ ', the 23 _2), the movable core (23 _1, 23 _1', 23 ₂₎ sleeves (24, 24 'in sliding contact with the inner housing (11) with made of a material harder than) Are fixed coaxially, and the sleeve (24, 24 ') and the inner housing (1) are fixed.
1) An electromagnetic valve characterized in that a valve mechanism (30 ₁ , 30 ₂ ) is formed between them. 2. The solenoid valve according to claim 1, wherein said sleeve (24, 24 ') is formed of a non-magnetic material.