JPH0755039A - Gas emergency trip valve - Google Patents

Abstract

PURPOSE:To reduce sliding failure of a sliding part and to improve reliability by providing a main valve presser in a shape to cover the periphery of a plunger. CONSTITUTION:A spring 8 interposed on a main valve 2 and a driving part K to energize the main valve 2 to the side of a main valve seat 9 is provided. Additionally, a main valve presser 10 holding the main valve 2 between the main valve 2 and the spring 8 and having a shape to cover the periphery of the plunger 1 against the driving part K is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manual reset type gas shutoff valve which is built in a gas meter and shuts off (closes) a gas passage upon receiving a signal from an electronic circuit. The present invention relates to a gas cutoff valve that returns (opens).

[0002]

2. Description of the Related Art The so-called microcomputer meter, which has already been put into practical use, measures and integrates the amount of gas used, and constantly monitors the flow rate of the gas to flow a large amount of gas that is different from the normal state of use, or to use gas for a long time. If it continuously flows, or if a signal from an external sensor such as a gas leak alarm is received, the microcomputer judges that it is abnormal and sends a current to the shutoff valve to shut off the gas and prevent the danger in advance. When safety is confirmed after shutting off the shutoff valve and you want to return (open) the shutoff valve,
A manual return-type gas cutoff valve in which a person pushes a mechanical return button provided on a gas meter to return the gas has been put into practical use.

Further, in recent years, in response to the need for remote control of the return operation from indoors, an automatic return type gas cutoff valve which is electrically operated for the return (valve opening) is also being developed. For example, it is a gas cutoff valve as disclosed in JP-A-4-254084.

A conventional gas cutoff valve will be described below with reference to the accompanying drawings. FIG. 3 shows a closed state of the conventional gas cutoff valve. In the figure, a drive unit K is a hollow coil 13 that gives an exciting force to move a main valve 12 fixed to a plunger 11 left and right in the figure, a yoke 14 that forms a magnetic circuit,
A permanent magnet 15 that excites one-sided attraction, a base 16 that is airtightly fixed to the main passage, and a guide pipe 17 that slides the plunger 1 inside the drive unit K are arranged. A spring 18 is compressed and interposed between the base 16 and the main valve 12.

A main valve seat 19 is arranged in the gas passage S so as to face the main valve 12. The main valve 12 is held by a main valve retainer 20. Thus, when a current is passed through the coil 13 to move the plunger 11 toward the main valve seat 19, the plunger 11 moves and the main valve 12 comes into close contact with the main valve seat 19 to close the gas. This operation is the same for both the manual reset type gas shutoff valve and the automatic reset type gas shutoff valve.

Next, when returning (valve opening) In the manual return type, when the person pushes the mechanical return button provided on the gas meter, the plunger moves to the drive section K side, and the main valve 12 becomes the main valve. Gas flows away from the seat. Further, in the automatic return type, an electric current for moving the plunger 11 to the drive unit K side is supplied to the coil 13 to move the plunger 11, and the main valve 12
Was separated from the main valve seat 19 and the gas flowed.

[0007]

However, in the above configuration, the sliding portion between the plunger 11 and the guide pipe 17 is always exposed to the gas atmosphere, and therefore is included in the gas atmosphere. There is a problem that it becomes stuck due to the influence of water content, tar content, etc., causing sliding failure and corroding the plunger 11. Further, there is a problem that sliding failure occurs due to the corrosion of the plunger 11.

The present invention solves such a conventional problem and reduces the occurrence of sliding failure between the plunger 11 and the guide pipe 17, which reduces the water content and tar content in the gas atmosphere invading the sliding portion. The purpose is to

[0009]

In order to solve the above problems, a gas cutoff valve according to the present invention comprises a main valve mounted on a plunger and a main gas passage having a main valve seat on the opposite surface of the main valve. ,
An airtight drive unit for driving the plunger with an electromagnetic force, a spring for interposing the main valve and the drive unit to urge the main valve toward the main valve seat, and a main unit between the main valve and the spring. A main valve retainer having a shape that holds the valve and opposes the drive unit and covers the periphery of the plunger is provided.

[0010]

With the above means, the gas cutoff valve of the present invention covers the peripheral portion of the plunger against the drive portion and is isolated from the atmosphere in the gas. Therefore, sliding of moisture or tar between the plunger and the guide pipe is achieved. The adverse effect on can be cut off.

[0011]

Embodiments of the gas cutoff valve of the present invention will be described below with reference to the accompanying drawings. 1 and 2 show the open / closed state of an embodiment of the gas cutoff valve of the present invention, in which the drive unit K is a hollow coil that gives an exciting force to move the main valve 2 fixed to the plunger 1 left and right in the figure. 3, a yoke 4 forming a magnetic circuit,
A permanent magnet 5 that excites one-sided attraction, a base 6 that is airtightly fixed in the main passage S, a plunger 1 slides inside the drive unit K, and a resin or metal that has lubricity and wear resistance at least on the surface A metallic guide pipe 7 in which fine particles of a compound are co-deposited in a metal matrix is arranged.

A spring 8 is provided between the base 6 and the main valve 2.
Is compressed and installed. Further, a main valve seat 9 is arranged in the main passage S so as to face the main valve 2. Main valve 2 and spring 8
A main valve retainer 10 is provided between the main valve retainer 10 and the main valve retainer 10 in a shape that holds the main valve 2 and opposes the drive unit K to cover the plunger 1.

In this way, when a current for moving the plunger 1 to the main valve seat 9 side is passed through the coil 3, the plunger 1 moves and the main valve 2 comes into close contact with the main valve seat 9 to close the gas. This operation is the same for both the manual reset type gas shutoff valve and the automatic reset type gas shutoff valve. Next, when returning (valve opening) In the manual return type, when the person pushes the mechanical return button provided on the gas meter, the plunger 1 moves to the drive unit K side, and the main valve 2 moves to the main valve seat 9 The gas flows further away. In the automatic return type, a current is supplied to the coil 3 to move the plunger 1 toward the drive unit K, and the plunger 1 is moved.
The main valve 2 is separated from the main valve seat 9 so that gas flows.

As described above, in the gas cutoff valve, since the plunger 1 slides inside the guide pipe 7,
Suppressing moisture and tar from entering the sliding portion between the plunger 1 and the guide pipe 7 is the most effective means for eliminating sliding failure.

In the gas cutoff valve of the present invention, since the main valve retainer 10 having a shape covering the periphery of the plunger 1 is provided so as to oppose the drive portion K, the plunger 1 and the guide pipe 7 are provided.
The moisture and tar content can be reduced between the above and, and the sliding failure between the plunger 1 and the guide pipe 7 can be reduced.

[0016]

As is apparent from the above description, in the gas cutoff valve of the present invention, the main valve retainer having a shape that covers the periphery of the plunger against the drive portion K is provided, so that the plunger and the guide are prevented. It is possible to reduce intrusion of moisture and tar between the pipe and the pipe, and reduce sliding failure between the plunger and the guide pipe.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a closed state of a gas cutoff valve according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an open state of the shutoff valve.

FIG. 3 is a sectional view of a conventional gas cutoff valve.

[Explanation of symbols]

 1 Plunger 2 Main valve 7 Guide pipe 8 Spring 9 Main valve seat 10 Main valve retainer K Drive section S Main passage

Claims (1)

[Claims] 1. A main valve attached to a plunger, a main gas passage having a main valve seat on an opposite surface of the main valve, an airtight drive unit for driving the plunger with an electromagnetic force, and the main valve. And a spring interposed in the drive unit for urging the main valve toward the main valve seat, a main valve being held between the main valve and the spring, and the plunger against the drive unit. A gas cutoff valve provided with a main valve retainer shaped to cover the periphery of the.