JPS61282681A - Emergency gas shut-off device - Google Patents

Abstract

PURPOSE:To improve safety through shut-off of gas with the aid of an auxiliary shut-off valve even if shut-off motion by the shut-off valve is checked, by a method wherein an auxuliary shut-off valve, airtightly shutting off a gas flow passage in linkage with return control, is situalted to a return means adapted to return the shut-off valve to an opening state. CONSTITUTION:To return a shut-off valve 2, closed due to a gas leak trouble, through push-in of a return shaft 6, an on-off valve 65 is forced into contact with a valve seat 4', attached to the edge of an opening 5, through energization of a spring 64. In which case, the sut-off valve 2 is pushed by the return shaft 6 for return. With the shut-off valve 2 returned, opening and closing of a gas flow passage by the shut-off valve 2 is brought into an opening state, but in which case, since an on-off valve 65 already closed an opening 5, the presence of the on-off valve 65 serving as the auxiliary shut-off valve results in prevention of flowing of gas in a state in that the return shaft 6 is pushed in.

Description

[Detailed Description of the Invention] [Object of the Invention] <Industrial Application Field> The present invention is directed to an emergency shut-off device that operates a shut-off valve to stop gas based on the output from a gas leak detection device, particularly for a shut-off valve. This invention relates to a gas emergency shutoff device whose operation is performed by a release type electromagnet.

BACKGROUND ART In recent years, gas leak detection devices have been provided that include gas flow rate detection means and monitoring means comprised of a microcomputer that constantly monitors the output of this detection means. This system not only activates the shutoff device when an abnormal flow of gas is detected, but also allows this state to continue for a long time even if the flow is only the amount consumed by normal gas appliance combustion. It is highly safe because the gas can be shut off as an abnormal situation.

As an emergency shutoff device operated by the output of such a gas leak detection device, one consisting of a release type electromagnet and a shutoff valve driven by the output of the electromagnet is used. As shown in Fig. 3, a permanent magnet 1 built into a release type electromagnet 1
The magnetic force of 0 holds the shutoff valve 2 open against the bias of the spring 3, and the output from the gas leak detection device causes the electromagnet 1 to open.
When the valve is excited, the magnetic force of the permanent magnet 10 is canceled by the electromagnet 1, so that the shutoff valve 2 is operated by a spring bias and comes into contact with the valve seat 4, and is in a closed state.

Here, since the release type electromagnet 1 is used which operates the cutoff valve 2 by releasing it from the magnetic force of the permanent magnet 10, the cutoff valve 2 which has been activated and is in the closed state is returned to the open state. Therefore, it is necessary to push the shutoff valve 2 and attract it again to the permanent magnet 10, and therefore it is necessary to provide a return means. In the figure, 6 is a return shaft for this return, and when this return shaft 6 is pushed against the spring 7, the cutoff valve 2 is pushed back and re-adsorbed to the permanent magnet 10.
Open the valve.

<Problems to be Solved by the Invention> By the way, in the device having the above-mentioned return means, if the return shaft 6 is fixed in the pushed-in state, the operation of the shutoff valve will be hindered, and this will cause abnormalities. This is a very inconvenient situation in which the flow of gas cannot be stopped.

The present invention has been made to solve these problems.

[Structure 1 of the Invention: Means for Solving Problems] The present invention provides an emergency shutoff device equipped with a shutoff valve that is activated by the release action of a release type electromagnet to perform a closing operation, in which the shutoff valve returns to the open state. A feature of the present invention is that the return means for this purpose is provided with an auxiliary shutoff valve that airtightly shuts off the gas flow path in conjunction with the return operation.

According to the present invention, when the return means is operated to return the cutoff valve to the open state, the auxiliary cutoff valve provided in the return means hermetically blocks the gas flow path, and the return means closes off the gas flow path. Even if the shutoff valve is fixed in its returned state and the shutoff operation by the shutoff valve is prevented, the gas is still stopped by the auxiliary shutoff valve at this time.

<Example 1> Figure 1 shows an example of the present invention, in which a partition wall 8 having a circular opening 5 is provided. A cylindrical body 60 having a valve nozzle 61 at one end and a return shaft 6 at the other end is inserted into the opening 5 in the partition wall 8, and a return spring disposed between the partition wall 8 and the return spring 60 is inserted into the opening 5 of the partition wall 8. 7, the cylindrical body 60 and the return shaft 6 coaxial therewith are biased to the right in the figure. The outer circumferential surface of the cylindrical body 60 is in contact with a sealing means 9 such as an O-ring provided on the inner circumferential surface of the opening 5 of the partition wall 6. Note that the gas flows from the right side in the figure through the inside of the cylindrical body 60 to the left side in the figure.

A release type electromagnet 1 that operates a shutoff valve 2 by the output from a gas leak detection device is equipped with a permanent magnet 10, and has a shutoff valve 2 provided at one end of a movable iron core 11, and a shutoff valve 2 operated by an output from a gas leak detection device. The valve 2 is biased in the protruding direction by a spring 3, and the excitation of the electromagnet 1 is designed to cancel the magnetic force of the permanent magnet 10. Permanent magnet 1
The movable iron core 11 can be attracted and held against the spring 3 with zero magnetic force, and if the electromagnet 1 is excited, the magnetic force that tries to hold the movable iron core 11 becomes smaller than the force of the spring 3. , the movable iron core 11 protrudes by the force of the spring 3 and moves the cutoff valve 2 toward the partition wall 8, and as a result, a seal packing on the face of the cutoff valve 2 is formed on the end face of the valve/χ loop 61 of the cylindrical body 60. 14, the gas flow path is closed.

The shutoff valve 2 closed in this manner is returned to its original state by pushing in the return shaft 6 whose one end protrudes outside the container body. Here, the return of the shutoff valve 2 is performed by sealing means 9 on the outer peripheral surface.
The valve nozzle 61 of the cylindrical body 60 is in contact with the shutoff valve 2
This is done while the gas flow is in contact with the seal packing 14, that is, the gas flow is stopped, and the gas flow path is opened by returning the cylindrical body 60 and the return #I6. While the return operation is being performed, the sealing means 9 is in contact with the outer peripheral surface and the cylindrical body 6 is in contact with the shutoff valve 2.
0 constitutes an auxiliary shutoff valve that hermetically shuts off the gas flow path.

Another embodiment is shown in FIG. 12, in which the return means is as follows:
A return shaft 6 and an on-off valve 65 through which the return shaft 6 is threaded.
, the distance between the bone 7 that urges the return shaft 6 and the on-off valve 65 is J!
! A seal packing 67 is attached to one surface of the on-off valve 65, and a sealing means 69 such as an O-ring is attached to the inner peripheral surface of the insertion portion of the return shaft 6.

The spring force of the spring 66 is smaller than the spring force of the spring 7, and since the head 67 at one end of the return shaft 6 is engaged with the on-off valve 65, the on-off valve 65 is normally separated from the partition wall 8. It becomes. The cutoff valve 2 also has an opening 5 in the partition wall 8.
The gas flow path is closed by contacting the valve seat 4 formed on the edge of the valve.

In order to restore the shutoff valve 2 which has been activated and closed due to an abnormality such as gas leakage, the return shaft 6 may be pushed in. As a result of this operation, the pest control valve 65 comes into contact with the valve seat 4' provided on the rim of the opening 5 under the force of the spring 66, and is then pushed by the return shaft 6 to return the cutoff valve 2. When the shutoff valve 2 returns, the gas flow path llFfwi by the shutoff valve 2 becomes open, but at this time, the on-off valve 65 has already closed the opening 5, so it is not used as an auxiliary shutoff valve. Due to the presence of the on-off valve 65, gas does not flow even when the return shaft 6 is pushed in.

[Effect of the Invention 1] As described above, in the present invention, when the return means is operated to return the cutoff valve to the open state, the auxiliary cutoff valve provided in the return means hermetically blocks the gas flow path. Even if the shutoff valve is fixed in the reset state by the return means and the shutoff operation by the shutoff valve is prevented,
At this time, the gas is stopped by the auxiliary shutoff valve, and it is not possible to force the gas to flow in a situation where a shutoff action is required, so there is a risk of gas leakage or an accompanying gas explosion. It has high safety against such things.

[Brief explanation of drawings]

FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is a sectional view of another embodiment, and FIG. 3 is a sectional view of a conventional example, in which 1 is a release type electromagnet, 2 is a shutoff valve, 6 is a return shaft, 60 is a cylindrical body,
65 indicates an on-off valve. Agent Patent Attorney Ishi 1) Ai Shichiku 1 Figure 2

Claims (3)

[Claims] (1) In an emergency shutoff device equipped with a shutoff valve that is activated by the release operation of a release type electromagnet to perform a closing operation, the return means for returning the shutoff valve to the open state is provided with a gas flow path in conjunction with the return operation. A gas emergency shutoff device characterized by being equipped with an auxiliary shutoff valve that airtightly shuts off the gas. (2) The auxiliary shutoff valve is characterized by being formed of a cylindrical body that closes the gas flow path by contact with the shutoff valve, and also contacts the inner peripheral surface of the opening opened and closed by the shutoff valve in an airtight manner. A gas emergency shutoff device according to claim 1. (3) The auxiliary shutoff valve is slidably attached to the return shaft, one end of which serves as the return pressing part of the shutoff valve, and is attached in the direction that closes the gas flow path, which is the same direction as the operating direction of the return shaft. 2. The gas emergency shut-off device according to claim 1, characterized in that the gas emergency shut-off device is formed of an on-off valve that is energized.