JP2000179735A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress impact noise generated between a plunger and an attractor and between a valve element and a valve seat and to prevent the generation of metallic abrasion powder by interposing a nonmetallic buffer member between the plunger and the attractor, and using the nonmetallic valve element to seat the nonmetallic part of the valve element on the valve seat. SOLUTION: In this valve, a nonmetallic buffer member 10 is interposed between an attractor 2 and a plunger 3, and a nonmetallic valve element 4 is used as a spherical valve element. The buffer member 10 comprises a cylindrical fitting part 11, a collar part 12 and a columnar guide part 13 loosely fitted into a recessed part 21 of the attractor 2, and the whole is manufactured using appropriate engineering plastic. The thickness of the collar part 12 is set to appropriate dimension to prevent the attractor 2 and the plunger 3 directly abutting on each other. At least the surface side or the whole of the spherical valve element is manufactured using nonmetallic engineering plastic. The generation of impact noise and metallic abrasion powder can therefore be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve, and more particularly to a solenoid valve provided with a spherical valve body at the tip of a plunger to improve noise reduction and operation reliability.

[0002]

2. Description of the Related Art For example, an electromagnetic valve is often used for switching a circuit of a refrigerant circuit, and a solenoid valve having a relatively large valve opening stroke is employed. That is,
In this type of solenoid valve, a plunger is housed in a sleeve so as to be able to reciprocate freely, and an exciting coil is externally provided.
While energizing the excitation coil excites the attraction element, the plunger is attracted and the spherical valve element at the tip of the plunger is released from the valve seat. The valve element is caused to return by the biasing force of (1) to seat the spherical valve body at the tip of the plunger on the valve seat, thereby performing the valve action.

The suction element is fitted to the rear end of the sleeve and fixedly sealed by means such as TIG welding, and a housing for covering the exciting coil is fixed to the upper end of the suction element by screws. . A valve seat base having a valve seat is fitted to the distal end side of the sleeve, and is fixedly sealed by means such as brazing, and a pipe constituting an inlet and an outlet of a refrigerant is attached to the valve seat base. I have. Concave portions are formed on the distal end surface of the suction element and the rear end surface of the plunger, respectively, and a coil spring is contracted between the concave portions to bias the plunger.

In the conventional solenoid valve configured as described above, when an excitation coil fixed to the outside of the sleeve is energized, the plunger is attracted against the spring force of the coil spring, and the spherical valve element is detached from the valve seat. When the flow passage is opened and the energization to the electromagnetic coil is cut off, the plunger is urged by the spring force of the coil spring, and the spherical valve element is seated on the valve seat to close the flow passage. .

[0005]

However, in the conventional solenoid valve, the plunger and the attraction element abut when energizing the exciting coil, and the spherical valve element at the tip of the plunger and the valve seat abut when the energizing coil is energized. Since the suction element and the spherical valve element are generally made of a metal material, they generate an unpleasant impact noise at the time of abutment. In addition, since the material of the plunger and the suction element is an iron-based material including ferritic stainless steel, abrasion powder is likely to be generated at the time of abutment, and this is magnetically attached to the plunger and the suction element, causing a malfunction. there were.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, to suppress an impact noise generated between a plunger and a suction element and between a valve body and a valve seat, and to prevent generation of metal wear powder. Is to provide.

[0007]

Therefore, in the solenoid valve according to the present invention, a suction element is provided at the rear end of the sleeve, a valve seat is provided at the tip of the sleeve, and a plunger is provided in the sleeve between the suction element and the valve seat. The plunger is attracted by the magnetic force of the attracting element when the excitation coil is energized and the plunger is released from the valve seat, while the energizing force of the spring member is applied when the excitation coil is de-energized. In a solenoid valve in which the plunger is moved backward toward the valve seat and the valve body is seated on the valve seat, a buffer at the rear end of the plunger which comes into contact with the distal end surface of the suction element when the excitation coil is energized. A member is attached, and at least the surface side of a portion of the cushioning member that contacts the distal end surface of the suction element is made of a nonmetallic material, while at least a portion of the valve body that sits on the valve seat. Wherein the surface side is formed of a non-metallic material.

One of the features of the present invention is that a non-metallic buffer member is interposed between the plunger and the suction element, and a non-metallic valve element is used to avoid direct contact of the plunger with the suction element. In addition, the non-metal portion of the valve element is seated on the valve seat. Thereby, unpleasant impact noise during operation of the solenoid valve can be suppressed, and generation of metal wear powder can be prevented.

[0009] The cushioning member has a surface coated with a non-metallic material,
For example, a non-metallic sheet is adhered, and at least the surface side of the portion that comes into contact with the distal end surface of the suction element may be made of a non-metallic material. It is preferable that the entire cushioning member is made of a nonmetallic material. Similarly, the valve body may be configured so that at least the surface side of the portion seated on the valve seat is made of a nonmetallic material.
Considering the manufacturing process, it is preferable that the whole is made of a nonmetallic material.

The cushioning member may be fixed or adhered to the rear end surface of the plunger. However, a concave portion for accommodating a coil spring is generally formed on the front end surface of the suction element and the rear end surface of the plunger. Therefore, it is easy to attach the cushioning member using the concave portion on the rear end face of the plunger. That is,
While a concave portion is formed on the rear end surface of the plunger, the cushioning member is formed integrally with the columnar fitting portion and the fitting portion,
And a flange that is in contact with the distal end surface of the suction element, and the buffer member is preferably attached to the rear end of the plunger by fitting the fitting portion into a recess in the rear end surface of the plunger. .

In this case, a concave portion may be formed on the distal end surface of the suction element so as to face the concave portion on the rear end surface of the plunger, and a coil spring may be contracted between the bottom surface of the concave portion and the rear end surface of the flange portion of the cushioning member. it can. In such a structure, the coil spring expands and contracts in a free state. However, when the columnar guide portion is provided on the cushioning member, the expansion and contraction of the coil spring can be guided to stably expand and contract the coil spring. That is, the coil spring is housed in the concave portion of the suction element tip surface, and the buffer member has a columnar guide portion inserted into the coil spring housed in the concave portion and guiding the expansion and contraction of the coil spring integrally with the flange portion. It should be formed.

On the other hand, the valve body at the tip of the plunger may be of any form, such as being formed integrally with the plunger.
In consideration of the wear resistance of the valve body, the spherical valve body is rotatably attached to the tip of the plunger, and at least the surface side of the spherical valve body is made of a non-metallic material, and the portion on which the spherical valve body sits Should fluctuate naturally.

The non-metallic material used for the above-mentioned cushioning member and valve body may be, for example, rubber. However, considering that it is a mechanical part requiring durability, PBT (polybutylene terephthalate), PPS (polyphenylene sulfide), P
A (polyamide), PE (polyester), PTFE
An engineering plastic such as (polytetrafluoroethylene) is preferably used.

In the present invention, a non-metallic shock-absorbing member and a valve element are used. However, the use of only one of them has the effect of suppressing the generation of collision noise and metal abrasion powder.

That is, according to the present invention, a suction element is provided at the rear end side of the sleeve, a valve seat is provided at the tip of the sleeve, and the plunger is reciprocally housed in the sleeve between the suction element and the valve seat.
When energizing the exciting coil, the plunger is attracted by the magnetic force of the attracting element to separate the valve body at the tip of the plunger from the valve seat, and when the energizing coil is de-energized, the plunger is directed toward the valve seat by the urging force of the spring member. In the solenoid valve which is caused to move backward and the valve body is seated on a valve seat, a buffer member is provided at the rear end of the plunger, the buffer member being in contact with the distal end surface of the suction element when the excitation coil is energized. It is possible to provide an electromagnetic valve characterized in that at least a surface of a portion of the member that contacts the distal end surface of the suction element is made of a nonmetallic material.

Further, according to the present invention, a suction element is provided at the rear end side of the sleeve and a valve seat is provided at the tip of the sleeve, and the plunger is reciprocally housed in the sleeve between the suction element and the valve seat. When energizing the exciting coil, the plunger is attracted by the magnetic force of the attraction element to separate the valve element at the tip of the plunger from the valve seat, and when the energizing coil is de-energized, the plunger is biased by the biasing force of the spring member. In the solenoid valve, which is moved back toward the valve seat to seat the valve body on the valve seat, at least a surface side of a portion of the valve body seated on the valve seat is made of a nonmetallic material. A solenoid valve characterized by the above can be provided.

[0017]

According to the present invention, a non-metallic shock absorbing member is mounted on the side of the plunger which abuts on the suction element, and the material of the valve body which abuts on the valve seat is made of a non-metallic material. In response to energization / interruption of the exciting coil, the plunger abuts on the suction element, and it is possible to suppress the impact noise generated when the valve body is seated on the valve seat.

Further, since there is no collision between the metal materials, no metal wear powder is generated. As a result, the metal powder is not adsorbed to the plunger or the suction element due to the residual magnetism of the plunger or the suction element, and the reliability is high. Can be provided.

Further, the non-metallic buffer member is provided on the suction element.
In addition, since the non-metallic valve element is not directly connected to the valve seat, there is no danger that the buffer member or the valve element will be melted by the high heat generated when the sleeve and the suction element are welded and sealed, thereby providing high reliability. Quality can be guaranteed.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific examples shown in the drawings. FIG. 1 is a diagram showing a structural example of a preferred embodiment of a solenoid valve according to the present invention, and FIG. 2 is a diagram showing a structural example of a conventional solenoid valve.

First, in order to facilitate understanding of the present invention, the structure of a conventional solenoid valve of this type will be described. In FIG. 2, the solenoid valve is an excitation coil 200 covered by a housing 300 around a valve assembly (hereinafter, referred to as a valve ASSY) 100.
And the cover 300 is attached to the valve ASS by a screw 400.
It is configured to be fixed to the suction element 2 of Y100.

In the valve ASSY 100, a suction element 2 is inserted into an upper half portion of a cylindrical sleeve 1 and fixed by means such as TIG welding or the like, and a concave portion 21 is formed on a distal end surface of the suction element 2. Plunger 3 in lower half of sleeve 1
Is inserted reciprocally, and a recess 31 is formed in the rear end surface of the plunger 3 so as to face the recess 21 of the suction element 2, and is accommodated in the recesses 21 and 31 between the suction element 2 and the plunger 3. As a result, a coil spring (spring member) 5 is contracted, and a spherical valve body 4 is rotatably attached to the tip of the plunger 3.

A cylindrical portion of a valve seat base 6 is fitted to the lower end of the sleeve 1 and fixed by brazing or the like, and a valve is provided on the bottom of the valve seat base 6 in cooperation with the spherical valve element 4. A valve seat 7 forming a mechanism is formed, and a refrigerant inflow pipe 8 forming a refrigerant inlet at a cylindrical portion of the valve base 6 and a refrigerant forming a refrigerant outlet below the valve seat 7 at the bottom. Outflow pipe 9
Are fixed by means such as brazing.

In the above-described solenoid valve, when the excitation coil 200 is energized, the attracting element 2, the plunger 3 and the housing 300 constitute a magnetic circuit, and a magnetic flux is generated as shown by an arrow A. When the magnetic flux is generated, the attraction element 2 is excited, and an attraction force is generated between the attraction element 2 and the plunger 3, and the plunger 3 is attracted by the attraction element 2 against the spring force of the coil spring 5, and the impact force is generated. At the same time, the spherical valve body 4 sitting on the valve seat 7 is separated from the valve seat 7, and the refrigerant flows from the inflow pipe 8 to the outflow pipe 9. At this time, the suction element 2 and the plunger 3
Are both iron-based metal materials, so that they generate a large impact noise and generate metal abrasion powder at the abutting portion.

Next, when the power supply to the exciting coil 200 is cut off, the magnetic flux disappears, and hence the attraction force disappears.
The plunger 3 is urged by the spring force of the coil spring 5 and moves back toward the valve seat 7, the spherical valve body 4 is seated on the valve seat 7, and the flow of the refrigerant is shut off. At this time, since the spherical valve body 4 and the valve seat 7 are both made of a metal material, a large impact noise is generated, and metal wear powder is generated at the abutting portion.

FIG. 1 shows a preferred embodiment of a solenoid valve according to the present invention which solves the above-mentioned problems of the solenoid valve having the conventional structure.
In the figure, the same reference numerals as those in FIG. 2 indicate the same or corresponding parts.
In this example, a nonmetallic buffer member 10 is interposed between the suction element 2 and the plunger 3, and a nonmetallic valve element 4 is used as the spherical valve element.

More specifically, the cushioning member 10 is formed integrally with the cylindrical fitting portion 11, the upper end surface of the fitting portion 11, and has a flange portion 12 and a flange portion having a larger diameter than the fitting portion 11. 12 is formed integrally with the upper end surface and comprises a columnar guide portion 13 which is loosely fitted in the concave portion 21 of the suction element 2, and the whole thereof is PB
It is manufactured using an appropriate engineering plastic such as T, PPS, PA, PE, PTFE, and the like.

The fitting portion 11 of the cushioning member 10 is fitted and fixed in the concave portion 31 on the rear end surface of the plunger 3, while the columnar guide portion 13 is inserted into the concave portion 21 on the distal end surface of the suction element 2. It is loosely fitted with a gap between the side surfaces, that is, inserted into the coil spring 5, and the columnar guide 13 guides the expansion and contraction of the coil spring 5. The thickness of the collar portion 12 is set to an appropriate size so that the suction element 2 and the plunger 3 do not directly abut. By avoiding collision with the third member 3, it is possible to prevent generation of large impact noise and generation of metal abrasion powder at the collision portion.

On the other hand, the spherical valve element 4 has at least its surface side, preferably the whole, is made of a nonmetallic material such as PBT, PP.
Manufactured using engineering plastics such as S, PA, PE, PTFE, etc., the noise caused by the collision of the spherical valve body 4 when it is seated on the valve seat 7 can be suppressed, and the generation of metal wear powder is prevented. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structural example of a preferred embodiment of a solenoid valve according to the present invention.

FIG. 2 is a cross-sectional view showing a structural example of a conventional solenoid valve.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 sleeve 2 suction element 21 concave part of suction element tip surface 3 plunger 31 concave part of plunger rear end surface 4 spherical valve element 5 coil spring (spring member) 6 valve seat base 7 valve seat 10 buffer member 11 fitting portion 12 flange portion 13 columnar shape Guide part 100 Valve assembly 200 Excitation coil 300 Cover 400 Screw

Claims (8)

[Claims] An attraction element is provided at a rear end side of a sleeve, and a valve seat is provided at a tip end side of the sleeve. A plunger is reciprocally accommodated in a sleeve between the attraction element and the valve seat. While the plunger is attracted by the magnetic force of the attraction element to separate the valve body at the tip of the plunger from the valve seat, the plunger is moved back toward the valve seat by the urging force of the spring member when the excitation coil is de-energized. In a solenoid valve configured to be seated on a valve seat, a buffer member is attached to a rear end of the plunger, which abuts on a distal end surface of the suction element when energizing the excitation coil,
At least the surface side of a portion of the cushioning member that contacts the distal end surface of the suction element is made of a nonmetallic material, while at least the surface side of the portion of the valve body that sits on the valve seat is a nonmetallic material. An electromagnetic valve characterized by comprising: 2. A suction element is provided at a rear end side of a sleeve and a valve seat is provided at a tip end side of the sleeve. A plunger is reciprocally accommodated in a sleeve between the suction element and the valve seat. The plunger is attracted by the magnetic attraction of the attraction element to release the valve body at the tip of the plunger from the valve seat, and when the energizing coil is de-energized, the plunger is moved back toward the valve seat by the urging force of the spring member, and the valve body is moved. In a solenoid valve configured to be seated on a valve seat, a buffer member is attached to a rear end of the plunger, which abuts on a distal end surface of the suction element when energizing the excitation coil,
An electromagnetic valve, wherein at least a surface of a portion of the cushioning member that comes into contact with the distal end surface of the suction element is made of a nonmetallic material. 3. A recess is formed in a rear end surface of the plunger, and the cushioning member is formed integrally with the columnar fitting portion and the fitting portion, and abuts on a distal end surface of the suction element. The electromagnetic member according to claim 1 or 2, wherein the cushioning member is attached to a rear end of the plunger by fitting the fitting portion into a concave portion on the rear end surface of the plunger. valve. 4. A concave portion is formed on the distal end surface of the suction element so as to face the concave portion on the rear end surface of the plunger, and a coil spring is contracted between the bottom surface of the concave portion and the rear end surface of the flange portion of the cushioning member. The solenoid valve according to claim 3, wherein 5. A columnar shape which is inserted into the coil spring accommodated in the concave portion and guides the expansion and contraction of the coil spring in the buffer member. The solenoid valve according to claim 4, wherein the guide portion is formed integrally with the flange. 6. A suction element is provided at a rear end side of a sleeve, and a valve seat is provided at a tip end of the sleeve. A plunger is reciprocally accommodated in a sleeve between the suction element and the valve seat. The plunger is attracted by the magnetic attraction of the attraction element to release the valve element at the tip of the plunger from the valve seat, and the plunger is returned toward the valve seat by the urging force of the spring member when the excitation coil is not energized. An electromagnetic valve, wherein the valve body is moved to seat the valve body on a valve seat, wherein at least a surface side of a portion of the valve body seated on the valve seat is made of a non-metallic material. valve. 7. The spherical valve body according to claim 1, wherein the valve body is a spherical valve body rotatably attached to a tip of the plunger, and at least a surface side of the spherical valve body is made of a non-metallic material. solenoid valve. 8. The solenoid valve according to claim 1, wherein the non-metallic material is an engineering plastic.