JPH04165175A - Solenoid valve - Google Patents

Abstract

PURPOSE:To prevent fluid leak at the time of change-over so as to improve sealing performance by providing a seal between the flange of a movable column slidable to a solenoid part axial hole and the opening end part of the axial hole. CONSTITUTION:A valve seat 7 is closed by a spring in the operation 'off' state, and the compressed air of an actuator is exhausted from an exhaust port 23 through an output port 5 and exhaust passages 17, 20. When voltage is applied to a solenoid 2, a movable column 10 is moved downward against the elastic force of a seal 24, and a plunger 11 is lifted against a spring 15 so as to come in contact with the movable column 10, so that the compressed air is supplied to the actuator from an input port 6 through a communicating chamber 4 and the output port 5. When the compressed air is of high pressure, the movable column 10 and the plunge 11 ascend by differential pressure between a storage chamber 18 and the communicating chamber 4, so that a gap between the valve seat 7 and a poppet 12 becomes large to increase flow. The sealed state can be constantly kept by a seal 24 between the movable column 10 and a magnetic ring 22, and thus air leak at the time of change-over can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a solenoid valve, and is particularly applicable to a solenoid valve in which a column and a plunger are slidably provided in an axial hole of a solenoid portion, facing each other. Concerning effective techniques.

[Conventional technology]

As this type of electromagnetic valve, the following may be considered, for example.

That is, this solenoid valve includes a solenoid portion having a shaft hole, a valve body connected to one end of the solenoid portion, and having a communication chamber inside thereof communicating with the shaft hole and having a boat with a valve seat; A column and a plunger are provided in the shaft hole to face each other, and a biasing means for moving the plunger by a biasing force to press the valve seat, and the column is moved along the inner circumferential surface of the shaft hole. It has a movable structure.

Then, the plunger is moved in the direction of the column by a predetermined stroke by the magnetic attraction force of the solenoid part and brought into contact with the column, and then the column is moved in the direction toward the communication chamber while the plunger is attracted by the air pressure in the communication chamber. The plunger is moved another predetermined stroke in the opposite direction, thereby increasing the stroke of the plunger and increasing the fluid flow rate.

[Problem to be solved by the invention]

However, in the structure of the conventional solenoid valve described above, a seal is provided around the exhaust port in the storage chamber that has the open end of the shaft hole and the exhaust port and accommodates the flange of the column. When switching the flow path, the flange of the column may separate from the seal, potentially causing air leakage.

In addition, since the structure uses air pressure in the communication chamber to press the flange of the column against the seal to create a seal, when the air pressure is low, the pressing force against the sole is insufficient, resulting in air leakage and poor sealing. There is a risk or possibility that the

Furthermore, since the flange hits the magnetic ring provided at the open end of the shaft hole and prevents the column from sliding toward the communication chamber, the sliding of the column during ○N operation is affected by the magnetic force. There is a risk that you may be

The present invention has been made focusing on the above problems,
The purpose is to provide a solenoid valve that can prevent fluid leakage during switching and improve sealing performance.

Another object of the present invention is to provide a solenoid valve that can be used even at low fluid pressures.

Furthermore, another object of the present invention is to provide a solenoid valve in which the sliding movement of a movable column during ON operation is not affected by magnetic force.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

The structure of the solenoid valve of the present invention is a valve body comprising a solenoid part having a shaft hole, and a communication chamber connected to one end of the solenoid part, communicating with the shaft hole and having a boat with a valve seat inside. an electromagnetic valve comprising: a movable column and a plunger that are slidably provided in the shaft hole facing each other; and urging means that moves the plunger with an urging force and presses the plunger against the valve seat, The structure is such that a seal is provided between the flange of the movable column and the open end of the shaft hole.

In this case, between the flange of the movable column and the opening end of the shaft hole, the movable column and the plunger are attracted to each other by the magnetic force of the solenoid part during ON operation, and are prevented from moving toward the communication chamber side. A structure may be provided in which a stopper made of a non-magnetic material is provided to allow movement in the opposite direction.

[Effect]

According to the solenoid valve of the present invention, since the structure is such that a seal is provided between the flange of the movable column and the open end of the shaft hole, the sealed state can be maintained at all times, thereby preventing the occurrence of fluid leakage during switching. can be prevented and sealing performance can be improved.

Further, since the structure is such that sealing is performed by the elastic force of the seal, sealing can be performed regardless of fluid pressure, and therefore, a solenoid valve can be used even when the fluid pressure is low.

Further, between the flange of the movable column and the open end of the shaft hole, the movable column is attracted to the plunger by the magnetic force of the solenoid part when ON is activated, and is prevented from moving toward the communication chamber, and in the opposite direction. Since the structure includes a stopper made of a non-magnetic material that allows the column to move, the sliding movement of the movable column during the ON operation is not affected by magnetic force.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Embodiment 1] FIG. 1 is a cross section 1 showing a solenoid valve according to Embodiment 1 of the present invention.

The solenoid valve in Example 1 is of a three-boat type and has a valve body 1. A solenoid section 2 and a cover 3 are coaxially connected to the valve body 1.

The valve body 1 has a communication chamber 4, and the output ports 1 to 5 and the input ports communicate with the communication chamber 4.
A first valve seat 7 is provided protruding from the inner end of the valve 6 .

The solenoid section 2 has a shaft hole 8, a coil 9 is wound around the outer periphery of the shaft hole 8, and a movable column 10 and a plunger 11 are slidably opposed to each other on the inner peripheral surface of the shaft hole 8. It is set in.

The plunger 11 has a first poppet 12 and a flange 13 at its lower end, and a second poppet 14 at its upper end.

A spring 15 (biasing means) is provided between the flange 13 and a magnetic ring 16 provided at the lower opening end of the shaft hole 8. It has a function of pressing the first poppet 12 against the first valve seat 7.

Further, a groove-shaped first discharge passage 17 is formed on the outer peripheral surface of the plunger 11 .

The cover 3 has a discharge boat 23 in the center, and a storage chamber 18 connected to the shaft hole 8 of the solenoid part 2 is formed inside. The movable column 10 is slidably provided in the shaft hole 8 and has flanges 19 at its two ends, which are housed in the storage chamber 18.

The movable column 10 has a second discharge passage 20 at the center, and a second valve seat 2 at the lower open end of this second 14F outlet passage 20.
1 is installed protrudingly.

The gist of this embodiment is that a seal 24 and a stopper 25 are provided within the storage chamber 18.

That is, the seal 24 consists of a magnetic ring 22 provided at the flange 19 of the movable column 0 and the open end of the shaft hole 8.
is established between.

The seal 24 is made of a single-shaped elastic member, and its elastic force maintains the sealed state.

The stopper 25 is installed on the magnetic ring 22 and between the outer peripheral surface of the seal 24 and the inner peripheral surface of the storage chamber 18.

This stopper 25 has a function of preventing the movable column 10 or the plunger 11 from moving downward by attracting each other with the magnetic force of the solenoid part 2 when activated, and allowing them to move in the opposite direction. .

Further, this stopper 25 is made of non-magnetic plastic deck or metal, and due to its non-magnetic property, 1 sliding column 1
It has a structure that is not affected by zero sliding or magnetic force.

Next, the operation of the first embodiment will be explained.

In FIG. 1, in the OFF operating state shown on the left side, the biasing force of the spring 15 acts against the upward force due to the air pressure acting on the input port, so
moves downward, the first valve .].1.12 is pressed against the first valve seat 7, and the first valve seat 7 is in the closed state.

Further, the movable column 10 tries to move downward due to its own weight, or its downward movement is prevented by the elastic force of the seal 24, and is pressed against the flange 19 or the upper wall of the storage chamber 18.

A gap Sa and S between the plunger 11 and the movable column 10
b is formed.

As a result, the second valve seat 21 on the side of the movable column IO remains open, and the compressed air in the actuator is transferred to the output boat 5 and the first valve seat 21.
and discharge boat 2 via the second fJL exit route 17, 20.
Exhaust from 3 to 1.

In such an OFF operating state, when a voltage is applied to the solenoid section 2, the coil 9 is energized and the plunger 1
1 and the movable column 10 are attracted to each other, the movable column 10 moves downward against the elastic force of the seal 24, and the slide l-
By applying the flange 19 to the collar 25, a ○N operating state (not shown in FIG. 1) is obtained.

Thereafter, the plunger 11 rises by a stroke Sa against the biasing force of the spring 15 and comes into contact with the movable column IO.

In such abutting state, the first and second valves 117.
The valve 21 is opened, and the compressed air is transferred from the input port to the communication chamber 4,
It is supplied to the actuator via the output boat 5.

When the compressed air is at high pressure, a pressure difference is generated between the storage chamber 18 and the communication chamber 4, and this pressure difference acts on the movable column 10.

Therefore, the movable column 10 moves up by the stroke sb while the plunger 11 is attracted.

As a result, the gap between the first valve seat 7 and the first poppet 12 becomes larger, and the flow rate of compressed air increases.

When the compressed air is at low pressure, the differential pressure generated between the storage chamber 18 and the communication chamber 4 is small, so the movable column 10 cannot rise while adsorbing the plunger 11, and the compressed air is supplied at a normal flow rate. Ru.

Although it is possible to control the flow direction of compressed air in this way, since the seal 24 is provided between the flange I9 of the movable column 10 and the magnetic ring 22, the seal 24
The zero spring force allows the sealing state to be maintained at all times, which prevents air leakage during switching and improves sealing performance.
I can do it.

Further, since the structure is such that sealing is performed by the elastic force of the seal 24, sealing can be performed regardless of air pressure, and therefore a solenoid valve can be used even when air pressure is low.

Furthermore, since the non-magnetic plastic or metal stopper 25 is provided on the magnetic ring 22, even if the flange 19 of the movable column 10 comes into contact with the stopper 25, there is no magnetic resistance between the flange 9 and the magnetic ring 22. Therefore, the sliding movement of the movable column IO during ON operation is not affected by magnetic force.

[Embodiment 2] FIG. 2 is a sectional view showing a solenoid valve according to Embodiment 2 of the present invention.

The solenoid valve according to the second embodiment has almost the same structure as the above embodiment, but the stopper 25a is integrally molded with the outer cover 2a of the solenoid part 2 by plastic molding, and a seal 24a having a figure 7 shape is provided. The opening side of the seal 24a is directed toward the outer peripheral surface of the movable column IO.

Regarding the effects of the second embodiment, in addition to the effects of the first embodiment, since the stopper 25a is integrally molded with the outer cover 2a of the solenoid part 2 using a plus deck mold, the number of parts can be reduced. be able to.

Further, since the structure is such that a seal 24a having a figure 7 shape is provided and the open side of this seal 24a is directed toward the outer circumferential surface of the movable column 10, the inner circumferential surface of the shaft hole 8 and the inner circumferential surface of the movable column 10 It is possible to further improve sealing performance and durability against compressed air that flows in through the gap between the parts.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the above-mentioned Examples, and it is understood that various changes can be made without departing from the gist of the invention. Needless to say.

For example, in the embodiment described above, the case where a seal having a 1-shape or a 7-shape is provided between the flange of the movable column and the magnetic ring is described, but the present invention is not limited to this.
A seal having a U-shape can be used.

Further, in the above embodiment, the movable column is provided with a discharge passage.
We have explained port-type solenoid valves, but are not limited to these, and are not limited to 2-port type solenoid valves with a solid movable column, or solid movable columns with a pin between the plunger and poppet. It can be applied to 2-port or 3-port type solenoid valves.

In the above description, the invention made by the present inventor has mainly been explained in terms of its field of application, which is a solenoid valve operated by pneumatic pressure, but it can also be applied to a solenoid valve operated by hydraulic pressure.

〔Effect of the invention〕

Among the inventions disclosed in this application, the effects obtained by typical inventions are briefly described below.

(1) = between the flange of the movable column and the open end of the shaft hole
1 4 - Since the structure has a seal between the two, the sealed state is maintained at all times, which prevents fluid leakage during switching.
It is possible to improve the sealing performance.

(2) Since the structure is such that sealing is performed by the elastic force of the sole, sealing can be achieved regardless of fluid pressure, and therefore a solenoid valve can be used even when fluid pressure is small.

(3) On the inner wall of the storage chamber on the shaft hole opening side, the movable column or plunger is attracted to each other by the magnetic force of the solenoid part when turned on, preventing it from moving toward the communication chamber, and preventing it from moving in the opposite direction. Since the structure is provided with a stopper made of a non-magnetic material that allows this, the sliding movement of the movable column during ON operation is not affected by magnetic force.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a solenoid valve according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a solenoid valve according to a second embodiment of the present invention. 1...Valve body, 2...Solenoid part, 2a...Outer cover, 3...φ cover, 4...Communication chamber, 5...Output port, 6...Input capo-1~ , 7... First valve seat, 8... Shaft hole, 9... Coil, 10... Movable column, 11... Plunger, 12... First poppet, 13... Flange, 14... Second poppet, 15... Spring (biasing means), 16... Magnetic ring, 17... First discharge path, 18... Storage chamber, 19... Flange, 20... Second +JF outlet, 21... Second valve seat, 22... Magnetic ring, 23... Discharge boat, 24... Seal, 24a... Seal, 25...・Stopper, 25a...Stopper. Patent applicant Koganei Seisakusho Co., Ltd. Representative Patent attorney Daiso Tsutsui

Claims (3)

[Claims] 1. A valve body comprising a solenoid portion having a shaft hole, a communication chamber connected to one end of the solenoid portion and having an internal port communicating with the shaft hole and having a valve seat; A solenoid valve comprising: a movable column and a plunger that are slidably provided; and biasing means for moving the plunger by a biasing force to press it against the valve seat; A solenoid valve characterized in that a seal is provided between the open end of the valve and the open end of the valve. 2. Between the flange of the movable column and the opening end of the shaft hole, the movable column and the plunger are attracted to each other by the magnetic force of the solenoid part during ON operation, and are prevented from moving toward the communication chamber, and the movable column is prevented from moving toward the communication chamber in the opposite direction. 2. The solenoid valve according to claim 1, further comprising a stopper made of a non-magnetic material that allows the valve to move. 3. 3. The solenoid valve according to claim 1, wherein the stopper is formed integrally with the outer cover of the solenoid part by plastic molding.