JP2576285Y2 - solenoid valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a solenoid valve used for controlling various oil and pneumatic devices such as an air switching valve.

(Prior Art) As a conventional solenoid valve of this type, for example, there is one as shown in FIG. That is, reference numeral 100 denotes the entire solenoid valve, which is provided with a center post 101 of a substantially magnetic material, a coil 102 surrounding the center post 101, and a valve seat 103 provided opposite the center post 101. A plunger 104 is provided between the post 101 and the valve seat 103 so as to be able to reciprocate. The plunger 104 is constantly pressed against the valve seat 103 by a spring 105 interposed between the center post 101 and the plunger 104, and is kept in a closed state in a non-energized state. On the other hand, when the valve is opened, by energizing the coil 102, the plunger 104 is magnetically attracted to the center post 101 against the spring force of the spring 105 and is separated from the valve seat 103.

(Problems to be Solved by the Invention) In such an electromagnetic valve, the plunger 104 collides with the center post 101 and the valve seat 103, and the hitting sound is large. As a countermeasure, as an example, as shown in FIG. 7, it has been proposed to use a space between the plunger 104 and the center post 101 as a damper room.

That is, the plunger 104 is slidably supported via the bearing 106, and the gap between the bearing 106 and the plunger 104 is made small to absorb kinetic energy when the plunger 104 is operated.

However, such a solenoid valve requires a center post.
Although it is possible to reduce the tapping sound when colliding with 101, the tapping sound when the plunger 104 collides with the valve seat 103 cannot be reduced. In particular, when the duty is controlled by intermittently turning on and off the current, the tapping sound becomes large, and it is necessary to further reduce the tapping sound.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and an object thereof is to effectively reduce not only the tapping sound with the center post but also the tapping sound with the valve seat. An object of the present invention is to provide a solenoid valve.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a center post made of a magnetic material, a coil provided so as to surround the outer periphery of the center post, and a center post facing the center post are provided. A valve seat, a plunger reciprocally inserted between the center post and the valve seat via a bearing, and a plunger interposed between the plunger and the center post to press the plunger against the valve seat. A solenoid that opens the plunger by separating the plunger from the valve seat by energizing the coil, with a small gap between the sliding surface of the plunger and the bearing. The space between the center post and the plunger is configured as a damper chamber, and when the plunger moves to the valve seat side,
An elastic membrane member for urging the plunger in a direction away from the valve seat to reduce the moving speed of the plunger is used, and the elastic membrane member utilizes the elastic restoring force of the membrane section and suppresses the damper action of the membrane section. It is characterized by having a communication hole for making.

Further, the elastic membrane member has a projection extending in the axial direction from the membrane portion and fitted to the outer periphery of the plunger, and is fitted to the plunger so as to cover the projection of the elastic membrane member. It is also preferable to provide a fixing ring member for fixing the projection of the membrane member to the outer periphery of the plunger.

(Operation) In the electromagnetic valve having the above configuration, when the plunger is magnetically attracted to the center post, the kinetic energy at the time of collision is absorbed by the damper function of the damper chamber between the center post and the plunger.

On the other hand, when the plunger collides with the valve seat, the impact at the time of seating is absorbed by the spring action of the elastic membrane member balanced with the spring.

Further, by providing the fixed ring member, the protrusion of the elastic film member can be fixed to the outer periphery of the plunger, and the elastic film member and the plunger can be combined.

(Embodiment) Hereinafter, the present invention will be described based on the illustrated embodiment. In FIGS. 1 and 2 showing a solenoid valve according to a first embodiment of the present invention, reference numeral 1 denotes an entire solenoid valve, and a body 2 as a valve box having a substantially hollow interior, and an integral part of the body 2 A solenoid 3 is provided, and a plunger 5 inserted into the body 2 and provided to be able to freely contact and separate from a valve seat 4 as a valve seat. The solenoid 3 is formed by integrally forming a cylindrical coil 31 by resin molding, and a center post 6 is press-fitted and fixed to one end opening.
Then, the solenoid 3 and the body 2 are connected to the under plate 7.
And are integrally assembled by the cover plate 32.

The valve seat 4 in the body 2 is arranged to face the end face of the center post 6, and the plunger 5 is
The valve seat 4 reciprocates between the valve seat 4 and the valve seat 4. The plunger 5 is slidably inserted into the inner periphery of the dry bearing 8 as a bearing fixed to the under plate 7.

A spring 9 is mounted between the plunger 5 and the center post 6 in a compressed state.
The plunger 5 is pressed against the valve seat 4 by the spring force of (1), and is kept in a normally closed state. One end of the spring 9 is engaged with a concave portion 51 provided on the back surface of the plunger 5, and the other end is engaged with a concave portion 61 provided on an end face of the center post 6.

On the other hand, the valve seat 4 has a flat surface on which a first flow path 10 is opened, and the first flow path 10 is provided so as to penetrate a first nipple 11 formed to protrude along the center axis direction of the body 2. Have been. On the other hand, a second nipple 12 extending in a direction orthogonal to the first nipple 11 is formed in the body 2 so as to protrude therethrough, and a second flow path 13 opened in the body 2 is formed therethrough.

The space between the plunger 5 and the center post 6 is sealed to form a damper chamber 14. The damper chamber 14 communicates with a flow path in the body 2 through a gap between the dry bearing 8 and the sliding surface of the plunger 5.

Further, a diaphragm 15 is provided as an elastic film member for urging the plunger 5 in a direction to separate the plunger 5 from the valve seat 4. The diaphragm 15 has a seal rubber portion whose inner diameter end is integrally fixed to the tip of the plunger by baking.
16 and the outer diameter ends are the body 2 and the under plate 7
And is airtightly fixed between them with a holding plate 18 interposed therebetween.

The diaphragm 15 is conically inclined so that an inner diameter end portion protrudes toward the body 2. The diaphragm 15 defines a space between the plunger 5 side and the valve seat 4 side in the body 2 divided by the diaphragm 15. A communication hole 30 for removing a fluid such as air that communicates is provided. These communication holes 30 are not for producing an air damper effect, but
Plunger 5 side chamber and valve seat 4 divided by 15
It is provided to make the pressure in the space on the side equal.

The communication holes 30 in this embodiment are shown in FIGS. 3 (a) and 3 (b).
As shown in FIG. 4, four holes are provided at equal intervals on the inner periphery of the board surface of the diaphragm 15, and the shape of each communication hole 30 is a substantially elliptical shape extending in the circumferential direction from the center of the board surface of the diaphragm 15. It is.

The shape of the communication hole 30 may be another shape such as a circle, a sector shape tapering in the circumferential direction, or a spoke shape. Also, the number is not limited to four.

In the solenoid valve having the above configuration, when the coil 31 is energized to turn on the solenoid 3, the center post 6 is excited and the plunger 5 is magnetically attracted to the center post 6. The movement of the plunger 5 toward the center post 6 is buffered by the damper action of the damper chamber 14 between the center post 6 and the plunger 5, so that the impact when colliding with the center post 6 is absorbed.

That is, since there is a slight clearance between the plunger 5 and the dry bearing 8 supporting the plunger 5, the internal pressure in the damper chamber 14 surrounded by the plunger 5 and the center post 6 increases, and the air damper As a result, the operating speed of the plunger 5 is reduced. As a result, the speed at which the plunger 5 contacts the center post 6 is reduced, and the contact sound is reduced.

Next, when the plunger 5 moves to the valve seat 4 side, the diaphragm 15 integrated with the plunger 5 is set in a state of being balanced with the spring force of the spring 9 provided on the plunger 5, and comes into contact with the valve seat 4 or 0.2 [m
m].

When the plunger 5 moves toward the valve seat 4, an elastic restoring force due to the deformation of the diaphragm 15 is applied in a direction opposite to the traveling direction of the plunger 5, whereby the speed of the plunger 5 decreases and even if the plunger 5 comes into contact with the bubble seat 4. Hitting sound is small.

FIG. 4 shows a second embodiment of the present invention. In this embodiment, the plunger and the diaphragm are not molded integrally but are separately molded and assembled.

Therefore, the materials of the plunger 5 and the diaphragm 15 can be made different, and the material setting suitable for the functions of the plunger 5 and the diaphragm 15 can be made.

In other words, a material having a tapping and abrasion resistance required for a portion of the plunger 5 where a fluid seal is to be performed can be used for the plunger 5, while the responsiveness of the plunger 5 required for the diaphragm 15 is maintained, and
It is possible to use a material having elasticity for absorbing the kinetic energy of the diaphragm 15.

In this embodiment, the plunger 5 and the diaphragm 15 are fitted in the groove 5a provided in the plunger 5.
The inner peripheral edge 15b is fitted and fixed by vulcanization bonding.

FIG. 5 shows a third embodiment of the present invention. In this embodiment as well, the plunger and the diaphragm are not molded integrally but are separately molded and assembled. However, this embodiment differs from the second embodiment in the manner of assembling the plunger and the diaphragm.

That is, the diaphragm 15 is assembled in the groove 5a provided on the outer periphery of the plunger 5, and the inner diameter of the diaphragm 15 is temporarily fixed by expanding, and the stop ring 20 as a fixed ring member capable of fixing the plunger 5 in the circumferential direction is used. , Extending axially from the membrane of the diaphragm 15 to form the groove of the plunger 5
A projection 15a as a projection fitted to 5a prevents the diaphragm 15 from coming off in the pulling direction A.

Therefore, this embodiment has the following effects in addition to the effects of the second embodiment.

First, since the attachment of the plunger 5 and the diaphragm 15 is not performed by vulcanization bonding but is fixed to each other by the stop ring 20, the adhesive adheres to the sliding surface of the plunger 5 to increase the sliding resistance. And responsiveness are prevented from being adversely affected.

In addition, the mounting of the plunger 5 and the diaphragm 15 is simple because the stop ring 20 is simply fitted in combination with each other.

Other configurations, operations, and effects are the same as those of the above-described embodiment, and therefore, the same components are denoted by the same reference numerals, and description thereof will be omitted.

(Effects of the Invention) The present invention has the above-described configuration and operation, and the hitting sound when colliding with the center post can be reduced by the damper function of the damper chamber between the center post and the plunger. The impact sound at the time of impact on the center post and the valve seat can be reduced by absorbing the kinetic energy of the plunger and reducing the speed at the time of impact on the valve seat. Reduction can be efficiently achieved.

In addition, by providing the fixed ring member, the protrusion of the elastic film member can be fixed to the outer periphery of the plunger, and the elastic film member and the plunger can be combined with each other. Responsiveness, and in addition, the ease of assembly is improved.

[Brief description of the drawings]

1 and 2 show a solenoid valve according to a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a main part, FIG. 2 is a longitudinal sectional view showing the entire structure, FIG. (A) is a plan view of a diaphragm which is one of the constituent members of the solenoid valve according to the first embodiment, (b) is a longitudinal sectional view of (a) of FIG. 4, and FIG. FIG. 5 is a sectional view of a principal part of a solenoid valve according to a second embodiment of the present invention, and FIG. 5 is a sectional view of a principal part of a solenoid valve according to a third embodiment of the present invention.
FIG. 7 and FIG. 7 are longitudinal sectional views of a conventional solenoid valve. DESCRIPTION OF SYMBOLS 1... Solenoid valve, 2... Body (valve box) 3... Solenoid, 31... Coil 32... Cover plate 4... Valve seat (valve seat) 5. … Step, 6… Center post 7… Under plate 8… Dry bearing (bearing) 9… Spring 10,13… First and second flow path 11,12… First and second nipple 14 ... Damper chamber 15 ... Diaphragm (elastic membrane member) 16 ... Seal rubber part g ... Clearance

Claims (2)

(57) [Scope of request for utility model registration] 1. A center post made of a magnetic material, a coil provided to surround an outer periphery of the center post, a valve seat provided to face the center post, and a bearing between the center post and the valve seat. A plunger inserted between the plunger and the center post so as to be reciprocally movable, and a spring interposed between the plunger and the center post to press the plunger against the valve seat to hold the valve closed. In an electromagnetic valve that opens when the plunger is separated from the valve seat by energizing, the space between the center post and the plunger is configured as a damper chamber with a small gap between the sliding surface of the plunger and the bearing. An elastic membrane member for urging the plunger in a direction away from the valve seat to reduce the moving speed of the plunger when the plunger moves toward the valve seat; Elastic membrane member is a solenoid valve and having a communication hole for inhibiting the damping action of the film unit while utilizing the elastic restoring force of the membrane portion. 2. The elastic membrane member has a projection extending from the membrane in the axial direction and fitted to the outer periphery of the plunger, and is fitted to the plunger so as to cover the projection of the elastic membrane member. 2. A fixing ring member for fixing a projection of the elastic membrane member to an outer periphery of the plunger by using the fixing ring member.
Solenoid valve according to the above.