JPH0531335Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a solenoid valve used for controlling fluid pressure or vacuum pressure in industrial machines that utilize fluid pressure or vacuum pressure.

[Prior Art] Direct-acting solenoid valves are known in which a valve body that opens and closes a valve seat between an input port and an output port is directly opened and closed by a movable iron core of a solenoid operating section. be. In such a direct-acting solenoid valve, the movable core must be driven against the fluid pressure force acting on the movable core and the valve body, so it is difficult to increase the diameter of the valve seat or increase the fluid pressure. In order to achieve this, it is necessary to increase the electromagnetic attraction force accordingly, and it has been difficult to increase the distribution capacity without increasing the size of the electromagnetic operating section.

For example, as a solution to this problem,
As disclosed in Japanese Patent No. 60-89481, the valve body is controlled by a seal part that moves the valve body toward and away from the valve seat, a fixed part fixed to the valve body, and the action of fluid pressure at the input port between the seal part and the fixed part. It is composed of a bent part or a bellows-shaped bent part curved in the opposite direction to the direction, and the seal part is attached to the movable core in the core chamber inside the valve body,
An electromagnetic valve has been proposed in which the iron chamber and a port on the valve seat side are communicated with each other, and the diameter of the fixed portion side of the bent portion is approximately equal to the diameter of the valve seat.

In this solenoid valve, the diameter of the fixed part side of the bent part is made approximately equal to the diameter of the valve seat, so the valve body can be opened and closed with a small force regardless of the size of the valve seat diameter. Because they are curved or bellows-shaped in the opposite direction to the fluid pressure acting direction of the port, they tend to bend depending on conditions such as the shape of the bent portion and the level of fluid pressure acting on the bent portion. There is a problem in that the sealing force acting on the valve body becomes unstable and leaks are likely to occur.

[Problem to be solved by the invention] The problem to be solved by the invention is to provide a solenoid valve that can stably open and close the valve seat with a small force, regardless of the size of the valve seat diameter or the level of fluid pressure. There is a particular thing.

[Means for solving the problem] In order to solve the above problem, the solenoid valve of the present invention has the following features:
A solenoid valve in which a valve seat formed between an input port and an output port is opened and closed directly by a valve body attached to a movable core driven by an electromagnetic attraction force and a return spring, The valve body has an integrally formed thick seal portion that approaches and separates from the valve seat, and a thick seal portion that extends in a cylindrical shape from the seal portion, and that applies the fluid pressure almost equally in the direction in which the fluid pressure of the input port is applied. The flexible hakama part is curved so as to act, and the fixing part is connected to the end of the hakama part. It is attached to a movable core in a divided core chamber, the core chamber and a port on the valve seat side are communicated with each other, and the diameter of the end of the fixed part side of the hakama portion is approximated to the diameter of the valve seat. It is a feature.

[Operation] The movable core is driven by passing current to the electromagnetic operating section, and the valve seat is opened and closed directly by the valve body attached to the movable core.

When the valve seat is closed with the electromagnetic operating unit de-energized, the valve element is pressed against the valve seat by the biasing force of the return spring, and at this time, an acting force due to fluid pressure from the input port acts on the outer or inner surface of the valve element (the outer surface when the core chamber is connected to the output port, and the inner surface when it is connected to the input port). However, since the diameter of the end of the skirt portion on the fixed portion side is formed to be a size that approximates the diameter of the valve seat, there is almost no difference in the pressure-receiving area of the valve element in the opening and closing directions, and therefore almost no acting force due to fluid pressure acts on the valve element in the opening and closing directions.

In addition, when the valve seat is opened when the electromagnetic operating section is energized, the pressure fluid flowing from the input port to the output port flows into the core chamber, and the pressure inside and outside of the core chamber becomes the same, so the valve body is opened by the pressure fluid. Acting forces in the valve direction and valve closing direction do not act.

Furthermore, since the fluid pressure acting on the flexible hakama portion is approximately equal and the valve body does not tilt due to fluid pressure, the valve body can reliably seal the valve seat and prevent fluid leaks. , the fluid pressure acts evenly and the life of the valve body can be extended.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail based on the drawings. In FIG. 1, 1 is a valve body consisting of a valve box 1a and a valve lid 1b, Fluid input port 2 and output port 3
A valve seat 4 that opens into a valve chamber 5 is formed between both ports 2 and 3.

A valve body 8 that opens and closes the valve seat 4 within the valve seat 5
is a disc-shaped seal portion 8 that approaches and separates from the valve seat 4.
a, a flexible hakama part 8b extending in a cylindrical shape from the periphery of the seal part 8a, and curved in the direction in which the fluid pressure of the input port 2 is applied, on which the fluid pressure acts substantially evenly;
A flange-shaped fixing part 8 continuous to the end of the hakama part 8b
c, and the fixing portion 8c is made up of a valve lid 1b.
When the valve body 8 is opened and closed, it is fixedly supported by the valve cover 1b so as not to be deformed by forming one end with the hakama part 8b, and the fixed part 8c
The tip of the valve body 1a is fluid-tightly clamped and fixed between the valve box 1a and the valve cover 1b.

A movable core 12 is slidably disposed in a core chamber 11 defined between the valve body 8 and the electromagnetic operating section 10, and the tip of the movable core 12 is connected to a seal portion 8a of the valve body 8. The movable core 12 is also provided with a through hole 14 that communicates the output port 3 and the core chamber 11 through the valve seat 4 . This through hole 14 is located at the sealing portion 8 of the valve body 8.
It may be provided in a. Further, a return spring 15 is provided between the movable iron core 12 and the fixed iron core 13 to bias the movable iron core in the valve closing direction.

In the hakama portion 8b of the valve body 8, the diameter of the end 8d on the side of the fixed portion 8c, that is, the portion that becomes the fulcrum when the hakama portion 8b deforms when the valve body is opened and closed, is determined by the diameter of the valve seat 4. By this, the difference in pressure receiving area between the valve opening direction and the valve closing direction in the valve body 8 is made as small as possible.

Note that 17 in the figure is an electromagnetic coil.

In the solenoid valve having the above configuration, the movable core 12 is driven by passing current to the solenoid coil 17, and the valve seat 4 is opened and closed by the seal portion 8a of the valve body 8 attached to the movable core 12. . At this time,
The flexible skirt portion 8b bends as the valve body 8 opens and closes, thereby allowing the valve body 8 to open and close smoothly.

Here, when the valve seat 4 is closed with the coil 17 de-energized, the valve body 8 is pressed against the valve seat 4 by the biasing force of the return spring 15, and at this time, the outer surface of the valve body 8 is As shown by the arrows, the acting force due to the fluid pressure from the input port 2 acts in each direction, but the hakama portion 8
The diameter of the end 8d on the side of the fixed part 8c in b is formed to a size that approximates the diameter of the valve seat 4, thereby minimizing the difference in pressure receiving area of the valve body 8 in the valve opening direction and the valve closing direction. Since it is configured to approach 0,
Almost no force acting in the valve opening direction or valve closing direction due to fluid pressure acts on the valve body 8.

Further, even when the valve seat 4 is opened with electricity applied to the coil 17, the pressure fluid flowing from the input port 2 to the output port 3 through the valve seat 4 flows into the iron core chamber 11 through the through hole 14, Since the inside and outside pressures are the same, the force exerted by the pressure fluid in the valve opening direction and the valve closing direction does not act on the valve body 4.

Furthermore, by curving the flexible hakama portion 8b in the direction in which the fluid pressure of the input port 2 is applied so that the fluid pressure acts approximately evenly, when the valve body 8 opens the valve seat 4, Since the bending direction of the skirt portion 8b is always constant and no force is generated that prevents the valve from opening, the valve body 8 not only opens and closes the valve seat 4 stably regardless of the level of fluid pressure, but also allows the fluid pressure to act evenly. This can extend the life of the valve body.

Therefore, the valve body 8 is opened and closed with a constant small force almost regardless of the diameter of the valve seat 4 or the level of fluid pressure, thereby increasing the size of the solenoid valve. This makes it possible to expand distribution capacity without having to

2 and 3 show valve bodies having different structures, and in the one shown in FIG. 2, the end of the hakama portion 18b of the valve body 18 is fixed by extending in the axial direction. A portion 18c is formed, and the fixing portion 18 is fitted and supported by a circumferential support surface 19 provided on the valve lid 1b, and an inward locking edge 18e provided at the tip of the fixing portion 18c is inserted into a locking recess. In addition, in the case shown in FIG. 3, the narrow flange-shaped fixing part 28c of the valve body 28 is attached to the valve cover 1b within a recessed step 29 provided in the valve cover 1b. is fixed by a holding plate 30. The output port 3 and the core chamber 11 are communicated through a through hole 31 provided in the seal portion 28a of the valve body 28.

Note that the effects in these embodiments are the same as those in the first example above.
Since it is the same as that shown in the figure, its explanation will be omitted to avoid duplication.

In each of the above embodiments, the port on the valve chamber 5 side is used as the input port 2, and the port on the valve seat 4 side is used as the output port 3, but these relationships can also be reversed. That is, in the case shown in FIG. 4, the port on the valve seat 4 side is the input port 2, and the port on the valve chamber 5 side is the output port 3. Then, the input port 2 and the iron chamber 11 are communicated through a through hole 39 provided in the seal portion 38a of the valve body 38, and the skirt portion 38b is curved in the direction in which fluid pressure from the input port 2 acts, that is, toward the outside. ing.

Therefore, in this embodiment as well, due to the difference in pressure receiving area, almost no fluid pressure force acts on the valve body 38 in the valve opening direction or the valve closing direction, and the valve body 38 is driven with a small force. I can do it.

Further, when the valve seat is opened, the valve body 38 is not tilted by the skirt portion 38b, so the valve body 38 stably opens and closes the valve seat 4 regardless of the level of fluid pressure.

[Effects of the invention] According to the invention having the above configuration, the fluid pressure curved in the direction of action of the fluid pressure of the input port is applied almost uniformly between the sealing part and the fixed part of the valve body. By providing a flexible hakama part, the valve body does not tilt due to fluid pressure, so the thick valve body can reliably seal the valve seat and prevent fluid leaks. The pressure acts evenly and the life of the valve body can be extended.

Therefore, the valve body can be opened and closed with a constant small force almost regardless of the size of the valve seat diameter or the level of fluid pressure. Capabilities can be expanded.

[Brief explanation of the drawing]

1 to 4 are cross-sectional views showing different embodiments of the present invention. 1... Valve body, 2... Input port, 3... Output port, 4... Valve seat, 8, 18, 28, 38...
...Valve body, 8a, 28a, 38a...Seal part, 8
b, 18b, 38b...Hakama part, 8c, 18c, 2
8c...fixed part, 8d...end part, 10...electromagnetic operation part, 11...iron core chamber, 12...movable iron core, 15
...Return spring.

Claims (1)

[Claim for Utility Model Registration] A valve seat formed between an input port and an output port is opened and closed directly by a valve body attached to a movable core driven by an electromagnetic attraction force and a return spring. In the solenoid valve, the valve body includes an integrally formed thick seal portion that approaches and separates from the valve seat, and a cylindrical extension extending from the seal portion,
and a flexible hakama part curved so as to apply the fluid pressure substantially uniformly in the direction in which the fluid pressure of the input port is applied, and a fixed part connected to an end of the hakama part, The fixed part is fixed to the valve body, and the seal part is attached to the movable core in the core chamber defined inside the valve body, and the core chamber and the port on the valve seat side are communicated with each other, and the seal part is fixed in the skirt part. A solenoid valve characterized in that the diameter of the end on the side is approximated to the diameter of the valve seat.