JPS6065977A - Gas shut-off valve - Google Patents

Abstract

PURPOSE:To enhance the safety of a gas shut-off valve, by providing such an arrangement that when an abnormality such as, for example, gas leakage, etc. occurs, a solenoid valve and a main valve are actuated in association with an external signal from a sensor, etc. to shut off both side nozzles, and when gas leakage is eliminated on the outlet side, the main valve is opened. CONSTITUTION:When an abnormality such as, for example, gas leakage, etc. occurs, shut-off current flows from an external signal source 9, an electro-magnet 10 is magnetized to have the same polarity as that of a permanent magnet 11, and therefore, due to the repulsive force of a spring 16 an attracting plate 18 is separated from the permanent magnet 11, and further, it pushes up a subvalve 12 through a spring 17 to close an inlet side nozzle 7a in a valve seat 7. If gas leakage still exists on the outlet side 6 even after closing of the subvalve 12, the pressure of the outlet side 6 lowers so that the resilient force of a spring 25 is effective to depress a main valve 22, resulting in closing of an outlet side nozzle 7b. Further, no gas leakage occurs on the outlet side 6, the main valve 22 does not closed so that the inlet valve 7a is opened when the handle 14 of a returning lever 15.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas cutoff valve, and more particularly to a gas cutoff valve equipped with a return safety mechanism.

In recent years, safety requirements for gas equipment and its handling have become increasingly strict from the perspective of preventing urban disasters.
Detect gas leaks from gas equipment or gas piping, etc., and if there is an abnormality such as a gas leak, immediately cut off the gas supply, and also confirm safety at 17 before returning. There is an urgent need for the development of a gas cutoff valve that does not allow gas to be resupplied until after the gas has been removed.

However, many of the gas leak alarms that have been in widespread use only issue an alarm and do not have a function to cut off the gas supply in the event of an abnormality, and are inadequate as a safety system for gas handling.

In addition, electromagnetic valve type cutoff valves combined with alarms are also known as cutoff devices, but none of these cutoff valves have a return safety mechanism and are far from complete as safety systems. In other words, the conventional means of confirming the safety of return is to install a gas leak detector or pressure gauge between the shutoff valve and the alarm to check for gas leakage on the gas outlet side, and then restore the shutoff valve. The idea was to do this.

However, with conventional shutoff valves that do not have a return safety mechanism, the presence or absence of an abnormality on the gas outlet side must be checked by a person with sufficient operating knowledge. There is a danger of it becoming thinner. In addition, if the return safety mechanism is a pressure gauge type, after sealing the pressure on the outlet side each time,
This method checks for the presence or absence of a pressure drop.Also, in the case of gas leak detectors, a bubble bottle filled with oil is used, but other methods often require inspection of the oil. However, it has disadvantages such as being complicated, requiring troublesome maintenance, management, and handling operations, and resulting in high costs.

In addition, solenoid valve-type shutoff valves also have metal contact parts in their movable parts, and OIJ rings are used to seal the movable shaft, so there is a lot of sliding resistance and there is a risk of them not working due to sticking. Ta. Therefore, in order to solve this problem, a large solenoid valve with a large driving force was required.

The present invention has been made in view of the various problems of such conventional gas cutoff valves, and in addition to solving these problems, works in conjunction with an alarm etc. to immediately cut off the gas supply in the event of an abnormality such as a gas leak, and A return safety mechanism that allows such abnormalities to be easily confirmed, does not allow the shut-off valve to return easily until after safety has been confirmed, and automatically operates only when the abnormality is completely corrected. The purpose of this invention is to provide a gas cutoff valve equipped with the following.

The invention will be explained below with reference to the accompanying drawings, which show examples of embodiments.

1 and 2 show schematic vertical cross-sectional views of the gas cutoff valve of the present invention, FIG. 1 shows the gas cutoff valve in the open state, and FIG. 2 shows the gas cutoff valve in the closed state. shows. In the figure, the gas cutoff valve of the present invention has a main body 1 having a substantially cylindrical outer shape, a flange portion 3, and a cover 2. The interior of the chamber is divided into a gas inlet side 5 and a gas outlet side 6 by an intermediate wall 4. A valve seat T is provided in the center with a double-sided nozzle that communicates between the inlet side 5 and the outlet side 6, and a small-diameter passage 8 that similarly communicates the inlet side 5 and the outlet side 6 is provided. At the same time, a solenoid valve B equipped with a return safety mechanism having a structure described later is provided on the inlet side 5, and a main pulp mounting portion C is provided on the outlet side.

□ That is, the intermediate portion of the main body 1 is divided by the intermediate wall 4 into a gas inlet side 5 and a gas outlet side 6, which communicate with a gas inlet 5' and a gas outlet 6', respectively. Further, in the center of the main body 1, there is a double-sided nozzle 7a which faces and communicates with the inlet side 5 and the outlet side 6, respectively.
and 7b is held and attached to the intermediate wall 4, and a small-diameter passage 8, which acts as a safety confirmation passage, communicates with the inlet side 5 and the outlet side 6, and is connected to the intermediate part of the valve seat 7. It is disposed by means such as being supported by the valve seat 7.

Next, the electromagnetic valve B equipped with a return safety mechanism is arranged opposite to the gas-filled 6-side nozzle 7a of the double-sided nozzle of the valve seat T.

However, this solenoid valve B is inserted between an electromagnet 10 connected to an external signal generation source 9, a permanent magnet 11 whose magnetization is lost depending on the direction of magnetization of the electromagnet 10, and the electromagnet 10 and the permanent magnet 11. , a nozzle 7IL with a valve seat T on the upper end.
Nozzle 7 facing the! A sub-pulp 12 for blocking L, a return lever 15 with a protrusion 13 that can be fitted and removed in the small-diameter passage 8, a lower end protruding outside the main body 1, and a handle 14, and a permanent magnet with the sub-pulp 12. An adsorption plate 18 is fitted into the return lever 15 between the magnets 11 and is slidably moved towards and away from the permanent magnet 11 by means of springs 16 and 17.
It consists of In addition, 19 is a small diameter passage 8 and a protrusion 1.
3 is an O-ring attached to the tip of the passage 8 for sealing with the main body. This is an O-ring to maintain airtightness with the inside.

10,000, the main pulp mounting part C, which is disposed on the gas outlet side facing the nozzle 7b of the valve seat T, has a main pulp 22 that blocks the nozzle ybfi7, and an outer periphery of the main pulp 7b of the main body 1 and the cover 2.
The diaphragm 24 is sandwiched between the rank part 3 to make the outlet side airtight, the back side is fixedly supported by the diaphragm receiving plate 23, and the main pulp 22 is fixed, the diaphragm receiving plate 23 and the top plate 2' of the cover 2. A spring 25 is mounted between the diaphragm receiving plate 23 and a spring 25 that biases the main valve 22 in the direction of blocking the nozzle 7b. It penetrates 2' and protrudes to the outside. This indicator 27 is provided so that whether or not the main pulp 22 is blocking the nozzle 7b of the valve seat T can be confirmed from the outside based on the displacement position. In addition, in the illustration, the display device 27 is protected by a protective cover 2''.

Next, the operation of the gas cutoff valve of the present invention will be explained.

First, during normal operation, as shown in FIG. 1, there is no signal from the signal source 9 such as an alarm, and the electromagnet 10 is held without electricity, and the adsorption plate 1B is adsorbed by the permanent magnet 11 and the sub-pulp 12 is also pulled together via the spring 1T, and the nozzle TIL is opened. Therefore, the main pulp 22 is pushed up against the elastic force of the spring 25 by the gas pressure flowing in from the inlet side 5, the nozzle 7b is opened, and the gas flows out from the outlet side and is used.

However, if an abnormality such as a gas leak occurs in the piping or gas equipment on the gas outlet side, a cutoff current flows from the external signal source 9 as shown in FIG. When magnetized with a polarity that cancels out the magnetic direction (polarity in the same direction as the permanent magnet 11 in FIG. 2), the adsorption plate 1B separates from the permanent magnet 11 due to the repulsive force of the spring 16, and further moves through the spring 1T. The sub-pulp 12 is pushed up and the inlet nozzle 7a is closed. sub pulp 12
After closing, if there is still a leak on the outlet side, the pressure on the outlet side 6 decreases, and if the pressure decreases below a certain level, the spring 25
The elastic force overcomes and the main pulp 22 is pushed down, and the nozzle 7b is also closed. Therefore, the valve seat 7 is maintained in a double airtight manner. Also, if there is a lot of leakage on the outlet side, use main pulp 2.
2 does not close, so when the handle 14 of the return lever 15 is pulled, the nozzle 7a is automatically opened by the return safety mechanism as will be described later, and the gas can be used.

Further, in the case where the supply gas pressure simply decreases, when the pressure falls below a certain level, the main pulp 22 is pushed down by the spring 25 and the nozzle 7b is closed. However, even if the pressure returns to normal, if there is a leak on the outlet side, the pressure on the outlet side will be low and the main pulp 22 will not open automatically, and the safety of the outlet side will be confirmed by the return safety mechanism described below. It will be opened automatically.

Next, the return safety mechanism is activated by the following operation.

That is, once the main pulp 22 is closed, if there is a leak on the outlet side, it will not open as described above, but if the leak on the outlet side is repaired, the main pulp 22 will be opened at the tip of the return lever 15. The protrusion 13 disengages from the small diameter passage 8 and a small amount of gas (approximately 5.5 tAr) gradually flows through the passage 8 to the outlet side 6. If there is no gas leakage on the outlet side and it is airtight, the pressure on the outlet side 6 will increase and the diaphragm 2
4 exceeds the elastic force of the spring 25, the main pulp 22 is pushed up together with the diaphragm 24, the nozzle 7b is automatically opened, and the gas flows from the inlet side to the outlet side. However, if there is a gas leak on the outlet side 6, the pressure on the outlet side 6 will not rise forever, so the main pulp 22 will not open.

Since the gas cutoff valve of the present invention has the configuration and operating mechanism described in detail above, it has many advantages as listed below.

1) If there is an abnormality such as a gas leak in the gas equipment or gas piping on the outlet side, the solenoid valve is immediately activated in conjunction with an external signal from a gas alarm, anti-seismic sensor, or other sensor, or by switching a switch, etc. Since the main pulp blocks the nozzles on both sides, double airtightness is maintained and a safety system for gas handling can be completed.

2) If there is a leak on the outlet side, the main pulp will not open for any length of time, so it is easy to check whether there is any abnormality on the outlet side.

3) To reset, simply pull the reset lever, and the main pulp will be opened automatically only when safety on the exit side is ensured, so it is safe no matter who operates it, and there is no chance of accidentally operating it. There is a lot of fear.

4) There are no sliding parts between metal parts in the movable parts, so there is no risk of non-operation due to sticking.

5) By providing an indicator connected to the main valve, the open/closed state of the main pulp can be immediately confirmed from the outside.

[Brief explanation of drawings]

1 and 2 show schematic cross-sectional views of the gas cutoff valve of the present invention, FIG. 1 shows the gas cutoff valve in an open state, and FIG. 2 shows the gas cutoff valve in a closed state. 1...Main body, 2...Cover, 4...Intermediate wall, 5.
...Gas inlet side, 6...Gas outlet side, 7...Valve seat,
7&, 7b...nozzle, 8...small diameter passage, 9...
- External signal generation source, 10... Electromagnet, 11... Permanent magnet, 12... Sub valve, 13... Protrusion, 15.
...Return lever, 18...Adsorption plate, 22...Main pulp, 23...Diaphragm receiving plate, 24...Diaphragm, 25...Spring. Patent applicant Yazaki Sogyo Co., Ltd.

Claims (2)

[Claims] (1) A valve seat with a double-sided nozzle that communicates between the inlet side and the outlet side and a small-diameter passage are arranged in the center of the main body, and the inlet is located at the upper end of the valve seat, facing the inlet side nozzle. A solenoid valve is provided, which includes a sub-valve that shuts off the side nozzle, a removable projection in the small-diameter passage, a movable return lever whose lower end protrudes outside the main body, and an electromagnet that operates the return lever; Further, a main valve mounting part is provided, which is provided with a diaphragm having a spring fixed to the back facing the outlet side nozzle of the valve seat, and a main valve fixed to the diaphragm and blocking the outlet side nozzle from deviating from the spring. gas shutoff valve. (2) The gas cutoff valve according to claim 1, characterized in that an indicator that moves integrally with the main valve is provided protruding from the outside of the main body.