JPH0660701B2 - Gas emergency shutoff device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application> The present invention relates to an emergency shutoff device that shuts off gas by operating a shutoff valve based on an output from a gas leak detection device, and in particular, for an shutoff valve. The present invention relates to a gas emergency shutoff device whose operation is performed by a release type electromagnet.

<Prior Art> As a gas leak detection device, there has recently been provided a device including a gas flow rate detection means and a monitoring means constituted by a microcomputer for constantly monitoring the output of the detection means. In this case, not only is the cut-off device activated when an abnormal flow of gas is detected, but this state continues for a long time even if only the flow rate consumed for the combustion of ordinary gas appliances is flowing. Since it is possible to shut off the gas when the time is considered to be abnormal, the safety is high.

As an emergency shutoff device which operates with the output of such a gas leak detection device, a device comprising a release electromagnet and a shutoff valve driven by its output is used. As shown in FIG. 2, the permanent magnet 1 contained in the release electromagnet 1
The magnetic force of 0 holds the shut-off valve 2 in the open state against the bias of the spring 3, and when the electromagnet 1 is excited by the output from the gas leakage detection device, the magnetic force of the permanent magnet 10 is canceled by the electromagnet 1. Therefore, the shut-off valve 2 is operated by spring force to come into contact with the valve seat 4 to be closed.

Since the release electromagnet 1 that operates the shutoff valve 2 by releasing from the magnetic force of the permanent magnet 10 is used here, the shutoff valve 2 that has been once operated and closed is returned to the open state. In addition, the shut-off valve 2 must be pushed so that it is attracted to the permanent magnet 10 again, and it is therefore necessary to provide a return means. Reference numeral 6 in the figure denotes a return shaft for this return, and if this return shaft 6 is pushed against the spring 7, the shutoff valve 2 is pushed back and re-adsorbed to the permanent magnet 10,
Open the valve.

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 is hindered, and thus the abnormal gas flow cannot be stopped. This is a very inconvenient situation.
Still another conventional example is, for example, Japanese Patent Laid-Open No. 54-7618.
In the publication, in order to temporarily shut off the gas flow passage when pushing the valve rod, an auxiliary valve body that is seated on one end surface of the cylindrical valve seat is attached to the lower end of the sleeve, and the cylindrical valve seat is attached to the tip side of the valve rod. There is disclosed a structure in which a valve element seated on the other end surface of the is attached.

<Problems to be Solved by the Invention> However, in Japanese Patent Laid-Open No. 54-7618, it is necessary to interpose an auxiliary valve body, a cylindrical valve seat, and a valve rod between the sleeve and the valve body. There is a problem in that the structure becomes complicated, the number of parts is significantly increased, and the cost is increased. Moreover, the auxiliary valve element is moved with a predetermined stroke to seat the auxiliary valve element on one end surface of the cylindrical valve seat, and from this state, the valve rod is moved with a predetermined stroke to separate the valve element from the other end surface of the cylindrical valve seat. Since it is necessary to do so, the total movement stroke of the movement stroke of the auxiliary valve body and the movement stroke of the valve rod becomes unnecessary, and there is a problem that the safety valve device becomes large. Moreover, if the valve element separates from the other end surface of the cylindrical valve seat before the auxiliary valve element is seated on the one end surface of the cylindrical valve seat, the abnormal gas flow cannot be stopped, and the auxiliary valve element will not move There is also the hassle of having to match the timing of seating on the end face with the timing of the valve body moving away from the other end face of the cylindrical valve seat.

The present invention has been made to solve such a problem, and under a situation where a shut-off operation should be performed, an abnormal gas flow is stopped for safety even if the return shaft is in any pushing position. In addition, the cylinder stroke required to return the shutoff valve to the open state can be shortened to reduce the size of the gas emergency shutoff device, simplify the structure, and reduce the number of parts. The present invention provides an emergency shutoff device for gas, which is capable of reducing the cost by reducing the increase in gas consumption.

[Structure of the Invention] <Means for Solving Problems> The present invention is an emergency shutoff device including a shutoff valve that operates by a release action of a release type electromagnet to perform a closing action, and returns the shutoff valve to a closed state. An auxiliary shutoff valve for airtightly shutting off the gas flow passage in conjunction with the returning operation is provided in the returning means for causing the auxiliary shutoff valve to come into airtight contact with the inner peripheral surface of the opening opened / closed by the shutoff valve. It has a valve nozzle that closes the gas flow path by contact with a shut-off valve on one end surface of the cylinder, and the other end surface of the cylinder slides one end outside the body. It is characterized in that the other end of the return shaft that freely projects is attached.

<Operation> According to the present invention, when the return means is operated to return the shutoff valve to the open state, the auxiliary cutoff valve provided in the return means hermetically shuts off the gas flow path, and the return means is operated. Even if the shutoff valve is fixed in the reset state and the shutoff operation by the shutoff valve is blocked, the gas is stopped by the auxiliary shutoff valve at this time.

<Embodiment> FIG. 1 shows an embodiment of the present invention, in which a circular opening 5 is formed.
The partition wall 8 having the 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 of the partition wall 8 and is arranged between the partition wall 8 and the return spring. 7, the cylindrical body 60
Also, the return shaft 6 coaxial with this is urged to the right in the figure. A sealing means 9 such as an O-ring arranged on the inner peripheral surface of the opening 5 of the partition wall 6 is in contact with the outer peripheral surface of the cylindrical body 60. 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.

The release type electromagnet 1 which operates the shutoff valve 2 by the output from the gas leak detection device is provided with a permanent magnet 10, and the shutoff valve 2 is provided at one end of the movable iron core 11 and the shutoff valve 2 is shut off. The valve 2 is biased by a spring 3 in the protruding direction, and the excitation of the electromagnet 1 is designed to cancel the magnetic force of the permanent magnet 10. Permanent magnet 1
With the magnetic force of 0, the movable iron core 11 can be attracted and held against the spring 3, and when the electromagnet 1 is excited, the magnetic force for holding the movable iron core 11 becomes smaller than the force of the spring 3. The movable iron core 11 projects by the force of the spring 3 and moves the shutoff valve 2 to the partition wall 8 side. As a result, the seal packing 14 on the one face of the shutoff valve 2 contacts the end face of the valve nozzle 61 of the cylindrical body 60. As a result, the gas flow path is closed.

The shut-off valve 2 thus closed returns by pushing the return shaft 6 whose one end projects inside the body. In this case, the shut-off valve 2 is returned to the seal means 9 on the outer peripheral surface.
Valve nozzle 61 of the cylindrical body 60 which is in contact with the shutoff valve 2
The seal packing 14 is in contact with the seal packing 14, i.e., the gas flow is stopped, and the gas passage is opened by the return of the cylindrical body 60 and the return shaft 6. Cylindrical body 60 in which the sealing means 9 is in contact with the outer peripheral surface and is in contact with the shutoff valve 2 while the return operation is performed.
However, it constitutes an auxiliary shutoff valve that hermetically shuts off the gas flow path.

Then, by pushing the return shaft 6 when the shutoff valve 2 is returned, the cylindrical body 60 constituting the auxiliary shutoff valve is hermetically contacted with the inner peripheral surface of the opening 5 opened and closed by the shutoff valve 2, Since the valve nozzle 61 integrally formed on one end surface of the body 60 contacts the shutoff valve 2 and moves the shutoff valve 2 in the direction away from the opening 5, gas leakage from between the cylindrical body 60 and the opening 5, Also, gas leakage between the shutoff valve 2 and the valve nozzle 61 is prevented. This state is continued until the shutoff valve 2 is attracted to the electromagnet 1 and the return shaft 6 is stopped from being pushed so that the shutoff valve 2 and the valve nozzle 61 are separated from each other. As a result, when the return shaft 6 is pushed in under the condition that the shutoff operation should be performed, even if the action of the shutoff valve 2 is hindered, the abnormal gas flow is stopped to enhance the safety. You can Moreover, since the movement stroke of the cylindrical body 60 required to return the shutoff valve 2 to the open state is short, the emergency shutoff device can be downsized. Further, since only one cylindrical body 60 is required to be interposed between the return shaft 6 and the shutoff valve 2, the structure can be simplified, and the number of parts can be prevented from increasing and the cost can be reduced. further,
The gas flow passage is closed only by contacting the valve nozzle 61 of the cylindrical body 60 with the shutoff valve 2, and the gas flow passage is opened only by separating the valve nozzle 61 from the shutoff valve 2. Therefore, as described in the conventional example. There is no need to adjust the timing when opening and closing the valve body.

[Effects of the Invention] As described above, in the present invention, the return means for returning the shutoff valve to the open state is provided with the auxiliary shutoff valve that hermetically shuts off the gas passage in conjunction with the return operation. The auxiliary shutoff valve is formed of a cylindrical body that is in airtight contact with the inner peripheral surface of the opening that is opened and closed by the shutoff valve, and a valve nozzle that closes the gas flow path by contact with the shutoff valve is integrally formed on one end surface of the cylindrical body. In addition, since the other end of the return shaft, which has one end slidably protruding outside the body, is attached to the other end surface of the cylindrical body, the return shaft is The abnormal flow of gas can be stopped at any pushing position to improve safety, and the stroke of the cylinder required to return the shutoff valve to the open state is shortened to reduce the size of the emergency shutoff device. Can be achieved. Furthermore, since only one cylindrical body is required to be interposed between the return shaft and the shutoff valve, the structure can be simplified, and the number of parts can be prevented from increasing and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional example. 1 is a release electromagnet, 2 is a shutoff valve, 5 is an opening, 6 is a return shaft, and 60 is a cylindrical body. , 61 are valve nozzles.

Claims (1)

[Claims] 1. A return means for returning the shut-off valve to an open state is provided with an auxiliary shut-off valve that hermetically shuts off a gas flow passage in conjunction with a return operation, and the auxiliary shut-off valve is opened and closed by the shut-off valve. Is formed of a cylindrical body that is in airtight contact with the inner peripheral surface of the opening, and a valve nozzle that closes the gas flow path by contact with a shutoff valve is integrally formed on one end surface of the cylindrical body. An emergency shutoff device for gas, wherein the other end is attached to the other end of a return shaft having one end slidably protruding outside the body.