JPH0158387B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Industrial Application Field This invention automatically shuts off the gas passage to prevent gas release when a gas leak occurs, and also prevents the gas from being released downstream when the gas supply is resumed. It concerns a gas safety device that makes it impossible to restart the gas supply if the cause of the leak has not been eliminated.

(2) Conventional Technology Gas leaks can lead to personal accidents, so research and development has been progressing in recent years on gas safety devices that automatically shut off the gas supply when a gas leak occurs.

The currently proposed gas safety device incorporates a shutoff valve linked to a gas leak alarm in the middle of the gas piping, and when the alarm detects a gas leak, the shutoff valve operates to stop the gas from flowing out, thereby shutting down the gas supply. The shutoff valve is reset for restarting by detecting the secondary pressure generated by the diaphragm, and the reset operation is performed by manually moving an operating section provided on the shutoff valve.

However, the use of a diaphragm for the shutoff valve has problems with durability, and since the reset operation part penetrates the valve box of the shutoff valve from the inside out, there are concerns about the sealing structure against gas leaks, and the operation part There is a problem that operation becomes inconvenient depending on the mounting position of the shutoff valve.

(3) Problems to be Solved by the Invention Therefore, the present invention eliminates the use of a diaphragm in the shutoff valve, allows the reset operation to be performed from any position, and eliminates the occurrence of a part that penetrates the inside and outside of the valve body. That is the problem.

(4) Means for Solving the Problems In order to solve the above problems, the present invention is constructed such that it is movable up and down in the middle of the gas passage, blocks the passage at the lowered position, and rises to the open position. a main valve that is elastically biased; a magnetic plunger that is provided directly above the main valve so as to be movable up and down; the magnetic plunger releases the main valve in a raised position and presses the main valve to a closed position when lowered; and the magnetic plunger A permanent magnet is placed directly above the magnetic plunger to attract and hold the plunger in the raised position, and a permanent magnet is placed outside the magnetic plunger to separate the plunger in the raised position from the permanent magnet and lower it, and to pull the plunger in the lowered position to the raised position. It consists of an electromagnetic coil that can change the excitation level, and a sub-valve that is movable up and down on the main valve to open and close the reset passage provided in the main valve. The plunger of the electromagnetic coil can be pulled up to the valve opening position via the plunger by an excitation force that raises the plunger of the electromagnetic coil.

(5) Function When no gas leak occurs, the plunger is in the raised position and held by a permanent magnet, and the main valve is pushed up to the open position by the spring, opening the valve hole in the gas passage and allowing gas to flow out. It is becoming available for use.

When a gas leak occurs and the gas leak alarm detects it, the electromagnetic coil is energized to energize the permanent magnet to cancel the magnetic force of the plunger, and the plunger descends to push the main valve to the closed position and open the gas passage. Shut off and stop gas from escaping.

To reset to use gas, the energization is switched so that the electromagnetic coil is energized to pull up the plunger, and the rising plunger attracts magnetism to the auxiliary valve by the magnetic force of the electromagnetic coil and pulls it to the valve open position.

The main valve maintains the closed position due to the difference between the primary pressure and the secondary pressure, but when the reset passage opens due to the rise of the auxiliary valve, the gas on the primary side flows to the secondary side, and the primary and secondary pressures are reduced. Once balanced, the main valve is raised to the open position by the upward force of the spring, allowing gas to be used.

If the cause of the gas leak has not been resolved at the time of reset, the pressure on the secondary side will not rise, the main valve will remain in the closed position, and the secondary valve will be pulled up via the plunger due to the electromagnetic coil being de-energized. The valve lowers under its own weight to the closed position, closing the reset passage and stopping gas from flowing out.

(5) Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings.

1 to 6 show different operating states of the gas cutoff valve, FIG. 7 shows a specific assembly structure of the cutoff valve, and FIG. 8 shows a circuit diagram of the gas safety device.

The gas cutoff valve 1 is provided with a valve hole 5 inside a valve box 2 that divides the gas passage into a primary passage 3 and a secondary passage 4, and directly above the valve hole 5 are a main valve 6, a sub-valve 7, and a magnetic plunger. 8, a permanent magnet 9 and the like are incorporated, and an electromagnetic coil 10 is arranged outside the plunger 8.

The main valve 6 is given elasticity by a spring 11 to normally rise to the valve open position, and is lowered to the valve seat 12 to shut off both passages 3 and 4 at the valve closed position.

The main valve 6 is provided with a recess 13 on the upper surface and a reset passage 14 penetrating vertically in the center part, and the sub valve 7 is arranged directly above the main valve 6 so as to be vertically movable. A shaft portion 7b that loosely fits into the reset passage 14 is connected to the lower surface of the head 7a that fits inside the head 7a, and a seal 7c is attached to the lower surface of the head. Note that the sub-valve 7 is formed using a magnetic material.

When the sub-valve 7 is in the open position raised relative to the main valve 6, the reset passage 14 is opened and the primary gas flows out into the secondary passage 4 through the gap with the shaft. It's getting old. (See FIG. 3) When the sub-valve 7 is in the closed position, lowered relative to the main valve 6, the seal 7c on the head overlaps the top surface of the main valve 6, blocking the reset passage 14. (See Figure 2) The magnetic plunger 8 is attached to the upper wall 2a of the valve box 2.
It is housed and held in a cylindrical part 15 provided so as to protrude upward from the cylindrical part 15 so as to be able to move up and down, and its lower end faces directly above the sub-valve 7.

A permanent magnet 9 and a magnetic material 16 are incorporated in the upper end of the cylindrical portion 15, and the plunger 8 in the raised position is attracted and held by the magnetic force of the permanent magnet 9.

When the plunger 8 is in the raised position, its entire length is contained within the cylindrical portion 15, and its lower end is located on the upper wall 2a of the valve box.
The vertical dimensions are set so that it is on the same level as the bottom surface of or slightly above it. (See Fig. 1) When the plunger 8 is in the lowered position where it is separated from the permanent magnet 9, the plunger 8 is connected to the main valve 6 via the sub valve 7.
The spring 11 is compressed by its weight, and the main valve 6
and the sub-valve 7 are held in the closed position. (See FIG. 2) The electromagnetic coil 10 surrounds the plunger 8 via a cylindrical portion 15 and gives vertical movement to the plunger 8. Excitation for pulling the plunger 8 away from the plunger and lowering it, and excitation for pulling up the plunger 8 from the lowered position to the raised position can be electrically switched.

5 and 6 show an example in which the open/closed state of the main valve 6 is electrically detected from outside the valve box 2, and a permanent magnet 18 is attached to the lower end of the downward supporting member 17 provided on the lower surface of the main valve 6. At the same time, a main valve opening/closing detection switch 19 which opens and closes by magnetic force is arranged on the lower surface of the valve box 2 directly under the permanent magnet 18.

The switch 19 may have a structure using a reed switch as shown in FIG. 5 or a movable body as shown in FIG. Since they are separated and the magnetic force does not act on them, the contacts of the switch 19 are in an open state. (See Figure 5) Also, when the main valve 6 is in the lowered closed position,
The permanent magnet 18 approaches the switch 19, and its magnetic force closes the contacts of the switch 19. (6th
In the electric circuit shown in Fig. 8, the gas leak alarm 20, the manual switch 21, and the electromagnetic coil 10 in the cutoff valve 1 are connected in series between the power supplies, and the electromagnetic coil 10 in the cutoff valve 1 is connected in parallel between the power supplies. The main valve on/off switch 19, the reset switch 22, and the delay relay TR are connected in series to the main valve on/off switch 1.
A relay R and a timer relay T are installed in parallel between the power source 9 and the reset switch and one power source.

Next, the operation of the cutoff valve will be explained with reference to the circuit diagram shown in FIG.

When there is no gas leak, the plunger 8 is attracted by the permanent magnet 9 and is in the raised position, and the main valve 6 is pushed up by the spring 11 and is in the open position, as shown in FIG.

If a gas leak occurs in this state, the contacts of the alarm 20 close, and the b contacts TRb, TRb of the delay relay TR
The electromagnetic coil 10 is energized via. At this time, the electromagnetic coil 10 is excited so as to cancel the magnetic force of the permanent magnet 9, and the plunger 8 descends to push down the sub-valve 7 and the main valve 6, thereby blocking the gas passage as shown in FIG.

Next, in order to reset the shutoff valve 1 to the open state in order to use gas, the reset switch 22 is pressed.
Press down with your fingertip.

The open/close detection switch 19 of the main valve 6 detects the closed state of the main valve 6 and is closed. Therefore, when the third contact 22c of the reset switch 22 is closed, the relay R is connected via the timer switch Ts. Power is applied, and each a contact Ra of relay R closes, delay relay TR
is energized, and relay R is self-held.

By energizing delay relay TR, b contact TRb,
TRb opens, and at the same time, the a contacts TRa and TRa close, and the direction of the current to the electromagnetic coil 10 is switched.
Therefore, the electromagnetic coil 10 is excited to pull up the plunger 8, and the plunger 8 rises and is held by the permanent magnet 9.

When the plunger 8 rises, the auxiliary valve 7 in contact with the lower end surface is pulled up from the main valve 6 to the open position by the magnetic force, opening the reset passage 14, so that the primary gas flows into the secondary passage 4. leaks into (See Figure 3) () When the cause of gas leakage has been resolved In this case, the gas pressure flowing out slightly from the reset passage 14 increases the gas pressure in the secondary passage 4, causing the primary side to the main valve 6 to The gas pressures in the passage 3 and the secondary passage 4 become equal, and the upward force of the spring 11 causes the main valve 6 to rise to the open position, opening the valve hole 5 and allowing gas to be supplied. (Situation shown in Figure 1) When the main valve 6 rises to the open position, the main valve open/close detection switch 19 becomes open, and the delay relay
The power to TR and relay R is cut off, the contacts of each relay are switched, and the circuit state shown in Figure 8 is restored.
This is in preparation for the next gas leak detection.

() If the cause of the gas leak has not been resolved, even if you leave the cause of the gas leak as is and press the reset switch 22, the plunger 8 and sub-valve 7 will rise as shown in Fig. 3, and the reset passage 14 will rise. is opened to let the gas flow into the secondary passage 4, but due to gas leakage, the secondary passage 4
The gas pressure does not rise, and the main valve 6 remains in the closed position due to the difference in gas pressure.

By energizing the relay R by pressing the reset switch 22, the timer T is activated, and the time required for the gas pressure in the secondary passage 4 to rise due to the gas flowing out from the reset passage 14 is set in advance. After a slightly longer period of time has elapsed, a timer switch Ts installed in series with the relay R opens, cutting off the power to the relay R and opening each contact Ra.

Therefore, when the delay relay TR is de-energized, the electromagnetic coil 10 is de-energized, the raised position of the plunger 8 is held only by the magnetic force of the permanent magnet 9, and the magnetic force that attracts the sub-valve 7 at the lower end disappears. Therefore, the sub-valve 7 descends under its own weight, blocking the reset passage 14 and stopping the outflow of gas, as shown in FIG.

As described above, if the cause of gas leakage is not eliminated, even if the reset switch 22 is pressed, only a small amount of gas will flow out, making the supply of gas impossible.

() When the cause of the gas leak is eliminated after the reset is impossible, as shown in Figure 4, with both the main valve 6 and the auxiliary valve 7 in the closed position and the plunger 8 in the raised position, the cause of the gas leak can be eliminated. After the problem is resolved, when the reset switch 22 is pressed, the first contact 22
a closes, the electromagnetic coil 10 is energized, the plunger 8 descends, and its lower end rests on the sub-valve 7, as shown in FIG.

At this time, the third contact 22c of the reset switch 22 is closed, and when the relay R is energized and each contact Ra is closed, the relay R is self-held.

Release the pressure on the reset switch 22 and turn on the second
When the contact 22b closes, the energization to the electromagnetic coil 10 is switched by the a contact TRa and the b contact TRb of the delay relay TR, and the plunger 8 absorbs magnetism to the sub-valve 7 and rises as shown in FIG. The passage 14 is opened to increase the pressure in the secondary passage 4, after which the main valve 6 is brought to the open position as shown in FIG. 1, and gas can be supplied.

(7) Effects As described above, according to the present invention, the above structure has the following effects.

(a) The plunger that operates the main and auxiliary valves to open and close positions is moved up and down using a permanent magnet and electromagnetic coil, so the reset can be controlled remotely electrically and the operating position can be set freely.

(b) The use of a diaphragm can be omitted to detect the secondary pressure, and the durability of the shutoff valve can be greatly improved.

(c) Remote control and reset operations require only switching the energization to the electromagnetic coil, which simplifies the operating circuit.

(d) It is safe because there is no need to worry about gas leakage because there are no parts that penetrate inside or outside of the valve box.

(e) The electromagnetic coil only needs to be energized when shutting off and resetting, making it safe and economical.

(f) By interlocking with a gas alarm, the outflow of gas can be shut off as soon as a gas leak occurs, improving the safety of gas use.

(g) The valve can be opened and closed simply by turning the switch on and off, so it can also be used as a gas tank.

(h) Safety is greatly improved because the gas supply cannot be restarted until the cause of the gas leak is eliminated.

[Brief explanation of drawings]

Each of FIGS. 1 to 6 is a longitudinal sectional view showing different operating states of the gas cutoff valve, FIG. 7 is a longitudinal sectional view showing a specific assembly structure of the cutoff valve, and FIG. 8 is the same as above. It is a circuit diagram of a safety device. 1 is a shutoff valve, 2 is a valve box, 3 is a primary side passage, 4 is a secondary side passage, 6 is a main valve, 7 is a sub valve, 8 is a plunger, 9 is a permanent magnet, 10 is an electromagnetic coil, 11 is a spring , 12 is a valve seat, 14 is a reset passage, 20
is the gas alarm, and 22 is the reset switch.

Claims (1)

[Claims] 1. A main valve installed in the middle of the gas passage so as to be movable up and down, and elastically biased to block the passage in the lowered position and rise to the open position; a magnetic plunger that releases the main valve in the raised position and presses the main valve to the closed position when lowered; and a permanent magnet that is placed directly above the magnetic plunger and attracts and holds the plunger in the raised position;
an electromagnetic coil that is disposed outside the magnetic plunger and is capable of switching between excitation that pulls the plunger in the raised position away from the permanent magnet and lowers it, and excitation that pulls the plunger in the lowered position to the raised position;
It consists of a sub-valve that is movable up and down on the main valve to open and close the reset passage provided in the main valve, and the sub-valve is made of a magnetic material and has an excitation force that raises the plunger of the electromagnetic coil. A gas safety device that is adapted to be pulled up to the open position via a plunger.