JPH0247821Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Field of Application>> This invention relates to a gas cutoff valve, and particularly to an improvement in the airtight structure between a valve body and a nozzle constituting a valve seat.

<<Prior Art>> As shown in FIG. 2, conventional solenoid-type gas cutoff valves include a valve body 4 provided at the tip of a plunger 3 that protrudes from a solenoid 2 assembled in a valve housing 1. The solenoid 2 is opposed to a nozzle 5 constituting a valve seat, and the solenoid 2 is driven by an external signal, and the protrusion of the plunger 3 presses the valve body 4 against the nozzle 5 to perform a valve closing action.

The tip of the plunger 3 and the valve body 4 are connected via a universal joint 6, and the valve body 4 is connected to the plunger 3 in a loose state, and a spring 7
is always biased toward the protruding side.

In this structure, when the solenoid 2 is energized, the plunger 3 is moved by the spring pressure of the spring 7.
protrudes, and the tip of the valve body 4 comes into contact with the edge of the nozzle 5.

In the abutting state, the valve body 4 self-displaces around the universal joint 6 as a center of swing, so that each part of the valve body 4 makes equal contact with the nozzle 5.

[Problems to be solved by the invention] By the way, as the isolation valve becomes smaller, if the solenoid is made smaller and driven with a lower load, it is necessary to set the spring pressure of the spring lower. .

Therefore, even if an attempt is made to self-displace the valve body using a conventional universal joint, the friction in this area is relatively large, so it does not adhere evenly to the edge of the nozzle and is completely shut off. There was a fear that there would be cases where this would not be possible.

The present invention was devised in view of the above problems, and its purpose is to enable the valve body to easily come into close contact with the valve seat even under low load, thereby achieving a complete shutoff state.

<<Means for solving the problem>> In order to achieve the above object, this invention provides a valve body at the tip of a plunger that protrudes from a solenoid assembled in a valve housing, and makes the valve body face a valve seat. In a gas cutoff valve in which the solenoid is driven by an external signal and a valve body is pressed against a valve seat by the protrusion of a plunger to close the valve, a gas flow path that communicates a nozzle constituting the valve seat with a gas downstream side. The valve body is supported by a rubber elastic body on the inner circumferential edge of the valve body, and the valve body is made of a hollow body, and a rubber tension membrane is provided on the nozzle contact surface, and the hollow interior of the valve body is communicated with the gas upstream side. It is characterized by

<<Operation>> The nozzle is displaced according to the protruding state of the valve body. Further, the tension membrane of the valve body bulges toward the nozzle side due to the differential pressure between the upstream and downstream sides of the gas, and serves as an auxiliary means for the biasing pressure by the spring.

<<Example>> Hereinafter, an example of this invention will be described in detail using the drawings.

FIG. 1 is a schematic explanatory diagram of a gas cutoff valve according to this invention.

Note that the same reference numerals are given to the same parts as in the above-mentioned conventional art for explanation.

In the figure, this cutoff valve basically has a plunger 3 protruding from a solenoid 2 assembled on the gas upstream side a of the valve housing 1, as in the conventional case.
A nozzle 1 is provided with a valve body 10 at the tip thereof, and the valve body 10 is provided in a gas flow path b that communicates with the gas downstream side C.
2, and the valve body 10 is moved together with the plunger 3 by the spring pressure of the spring 14 to the nozzle 12.
It is biased towards the side.

Even with this structure, when the solenoid 2 is energized and driven, the plunger 3 is projected by the spring pressure of the spring 14, and the valve body 10 is pressed against the nozzle 12, thereby performing a valve closing action.

However, the solenoid 2 is of a low-load drive type, and the spring pressure of the spring 14 is set accordingly.

The nozzle 12 is supported in a floating state on the inner peripheral edge of the gas flow path b via a ring-shaped rubber elastic body 16, and the ring-shaped edge is connected to the valve body 10.
towards.

On the other hand, the rear center of the valve body 10 is fixed to the tip of the plunger 3.

The valve body 10 is a hollow body with a front opening, and a rubber membrane 1 is attached to the front opening, that is, the nozzle contact surface.
8 is installed.

Further, a communication hole 20 is opened in one side of the valve body 10 to communicate the inside and outside of the valve body 10, and communicates the hollow portion of the valve body 10 with the gas upstream side a.

Next, the valve closing action when the gas cutoff valve having the above structure is activated will be explained.

When the solenoid 2 is energized and driven as described above, the plunger 3 protrudes due to the spring pressure of the spring 14 and presses the valve body 10 against the nozzle 12 to perform a valve closing action.

The spring pressure of the spring in this series of operations is weak, and the valve body 10 is in a protruding motion integrated with the plunger 3, but as the tension membrane 18 contacts the knife edge at the tip of the nozzle 12 in a ring shape, The nozzle 12 elastically deforms the rubber elastic body 16 and self-displaces in an attempt to uniformly hit the tension membrane 18, contrary to the conventional method.

In addition, in the latter half of the contact, a pressure difference is created between the gas upstream side a and the downstream side c with the tension membrane 18 in between, and as a result, the tension membrane 18 bulges toward the gas downstream side c.
The contact pressure against the nozzle 12 is increased.

Therefore, when the gas is shut off, the synergistic effect of the membrane protruding actions of the nozzle 12 and the valve body 10 ensures that the gas shutoff action is performed.

<<Effects>> As explained in detail in the above embodiments, in this device, the nozzle is displaced according to the protruding state of the valve body, and the tension membrane of the valve body is moved by the nozzle due to the differential pressure between the gas upstream and downstream sides. It bulges out to the side and serves as an auxiliary means for applying pressure to the nozzle.

Therefore, according to this invention, even if the solenoid used is of a low-load drive type, the valve body will surely come into close contact with the valve seat, resulting in a complete shutoff state, making it possible to downsize this type of gas cutoff valve. suitable for

[Brief explanation of drawings]

FIG. 1 is a schematic illustration of a gas cutoff valve according to this invention, and FIG. 2 is a schematic illustration of a conventional gas cutoff valve. 1...Valve housing, 2...Solenoid, 3...
... Plunger, 10 ... Valve body, 12 ... Nozzle,
16...Rubber elastic body, 18...Tension membrane, 20...Gas distribution hole, a...Gas upstream side, b...Gas distribution path, c...Gas downstream side.

Claims (1)

[Scope of utility model registration request] A valve body is provided at the tip of a plunger that protrudes from a solenoid assembled in a valve housing, the valve body is opposed to a valve seat, the solenoid is driven by an external signal, and the protrusion of the plunger causes the valve body to be brought into contact with the valve seat. In a gas cutoff valve that performs a valve closing action by pressing, the nozzle constituting the valve seat is supported via a rubber elastic body on the inner peripheral edge of a gas flow path that communicates with the gas downstream side, and the valve body is made of a hollow body. What is claimed is: 1. A gas cutoff valve comprising: a rubber membrane on a nozzle contact surface; and a hollow interior of the valve body communicating with a gas upstream side.