JPH1038133A - Gas valve opening/closing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a proper opening with a simple structure by detaching a magnet from an attraction plate and opening a water supply automatic valve in the case that water flow pressure reaches a value for securing opening enough to ignition. SOLUTION: When water flow passage is increased from a stopped state, a spindle 3 is abutted against a water supply automatic gas valve 4 and reaches a position immediately before starting the opening. An attraction plate 6 is then engaged with an engagement part 8. When the water flow passage is further increased from this state and exceeds attraction force between a magnet 2 and the attraction plate 6, the magnet 2 is removed from the attraction plate 6. The attraction force, having disburbed proceeding of the spindle 3, is eliminated. The water supply automatic gas valve 4 is opened at once to the extent for securing a rate of gas necessary for ignition. Fuel gas from a gas inlet is ignited by electrodischarging of an ignitor, and burning is started by a burner 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas valve opening / closing apparatus used in a gas water heater, and more particularly to an automatic water supply gas valve for opening / closing a gas passage to a burner in response to flowing water pressure.

[0002]

2. Description of the Related Art In general, a gas water heater is provided with an automatic water supply gas valve for opening a gas passage only when water is supplied to prevent empty cooking. However, since the water supply automatic gas valve uses the flowing water pressure as an operating source, the opening and closing operation of the gas flow passage is caused by the level of the flowing water pressure, so that a quick opening and closing operation cannot always be expected. Further, depending on the use conditions, the flowing water pressure is not always sufficient, and the flowing water pressure for opening and closing the automatic water supply gas valve may increase and decrease, and the automatic supply water gas valve may open and close unstable. Under such use conditions, the valve is in an incompletely opened state, so that the gas amount is too small, and the gas is not ignited, and raw gas is released or the fire is extinguished. In addition, there is a possibility that explosive ignition may be caused to the discharged raw gas by a re-ignition operation. Therefore, in the gas valve opening / closing device described in Japanese Utility Model Publication No. 55-34379, as shown in FIG.
Ring 43 for transmitting the pressing force by flowing water pressure
And a plate-shaped leaf spring 42 that performs a snap operation by this pressing force, and a pressing collar 41 that transmits the snap operation of the disk-shaped plate spring 42 to the automatic water supply gas valve 40, and only when a predetermined flowing water pressure is reached. There is known a gas valve opening / closing device that instantaneously opens and closes at a constant opening by transmitting a snap operation of a disc-shaped leaf spring 42 to an automatic water supply gas valve. In this water supply automatic gas valve, the required opening degree can be secured at the time of ignition at the time of opening, so that it is possible to ignite with a sufficient gas amount,
No ignition error occurs, and the emission of raw gas can be prevented.

[0003]

However, in such a gas valve opening / closing device, it is difficult to manufacture a plate-shaped leaf spring.
There was a problem that it became expensive. In order to ensure the function of the plate-shaped leaf spring, the load (reversal load) required for reversing and bending and the amount of displacement (reversal stroke) must be defined within a certain range.
In addition, due to the characteristics of the plate-shaped leaf spring, the reversing load with respect to the reversing stroke causes hysteresis between when the pressing force is applied and when the pressing force is released. If the predetermined accuracy is not obtained, there is a possibility that the opening degree of the automatic water supply gas valve may be insufficient, the water supply may be inverted after halfway opening, or may be kept inverted even when returning to the stopped state. there were. Therefore, in order to ensure this accuracy, the shape, thickness, material, and heat treatment of the plate-shaped leaf spring are strictly controlled, and it is strictly determined whether the gas valve opening and closing device operates properly even after assembly. Had to check. As a result, the gas valve opening / closing device has been expensive. Also, if you want to set a large amount of gas for ignition and fire extinguishing according to the equipment that consumes different amounts of gas and the calorific value of the gas to be used, increase the outer shape of the plate spring (increase the reversing stroke). Unless the opening degree of the automatic water supply gas valve is increased or the seat diameter of the automatic water supply gas valve itself is designed to be large, the gas amount cannot be secured, and the equipment cannot be made compact. An object of the present invention is to provide an inexpensive and highly reliable gas valve opening / closing device which solves the above-mentioned problems, enables a proper opening degree to be easily obtained with a simple structure, and provides an inexpensive and highly reliable device.

[0004]

According to a first aspect of the present invention, there is provided a gas valve opening / closing apparatus, wherein a spindle which moves forward and backward in response to flowing water pressure, and which opens and closes a gas passage in conjunction with the spindle. A gas valve opening / closing device provided with an automatic gas valve for supplying water, a magnet of a permanent magnet fixed to the spindle, an adsorption plate loosely inserted into the spindle from the magnet and adsorbed to the magnet, and When the spindle advancing as it rises reaches a position immediately before the water supply automatic gas valve is opened, a locking portion that locks the suction plate adsorbed on the magnet to prevent the spindle from moving forward. The spindle which moves forward with the rise of the flowing water pressure reaches the position just before the water supply automatic gas valve opens, and the flowing water pressure reaches a water pressure at which the opening can be opened to a sufficient degree for ignition. In this case, the magnet and the adsorbing plate are separated from each other to open the water supply automatic gas valve, and the spindle, which retreats as the flowing water pressure decreases, reaches a predetermined opening position of the water supply automatic gas valve. In this case, the gist of the present invention is that the attraction force between the magnet and the attraction plate is set such that the magnet is attracted to the attraction plate and the water supply automatic gas valve is closed.

According to a second aspect of the present invention, there is provided a gas valve opening / closing apparatus comprising: a spindle which moves forward and backward in response to a flowing water pressure; and a water supply automatic gas valve which opens and closes a gas passage in conjunction with the spindle. In the valve opening / closing device, an adsorbing plate fixed to the spindle, a permanent magnet that is loosely inserted into the spindle in a retreating direction from the adsorbing plate and adsorbs to the adsorbing plate, and moves forward with an increase in flowing water pressure. When the spindle reaches the position immediately before the water supply automatic gas valve is opened, a locking portion for locking the magnet adsorbed on the suction plate to prevent the spindle from moving forward is provided. When the spindle advancing with the ascent reaches a position just before the water supply automatic gas valve is opened, and the flowing water pressure reaches a water pressure that can be opened to a degree sufficient for ignition, the adsorbing plate, the magnet and When the spindle that retreats and opens the water supply automatic gas valve and retreats with a drop in the flowing water pressure reaches a predetermined opening position of the water supply automatic gas valve, the suction plate contacts the magnet. The gist is that the suction force between the suction plate and the magnet is set so as to be attracted and close the water supply automatic gas valve.

The gas valve opening / closing device according to the first aspect of the present invention having the above-described structure is provided with a locking portion when the spindle advancing as the flowing water pressure rises reaches a position immediately before the water supply automatic gas valve opens. Locks only the suction plate to prevent the spindle from moving forward. Then, when the flowing water pressure further increases and reaches a predetermined water pressure, the magnet and the attraction plate are separated. At this time, the flowing water pressure has reached the water pressure that can open the water supply automatic gas valve to a sufficient opening for ignition, so the magnet and adsorbing plate disengage and the spindle moves forward instantaneously, and the water supply with sufficient opening Open the automatic gas valve. Therefore, ignition can be performed with a sufficient amount of gas, so that no ignition error occurs and no raw gas is emitted. On the other hand, when the spindle that retreats as the flowing water pressure drops reaches the predetermined opening position (minimum opening that can continue combustion) of the automatic water supply gas valve, the magnet uses the suction force to attract the suction plate. , Retract the spindle instantly. Then, the magnet and the adsorbing plate are adsorbed, and the water supply automatic gas valve is securely closed. Therefore, in the transitional process of closing the valve, the flame does not disappear and the raw gas is not released. The required opening of the automatic water supply gas valve must be changed by changing the attraction force when the magnet and the attraction plate are separated when the valve is open, and the attraction force when the magnet and the attraction plate are attracted when the valve is closed. Is easy to set. Therefore, it is possible to easily set an appropriate opening degree according to a device having a different gas consumption and a calorific value of a gas to be used.

Further, the gas valve opening and closing device according to claim 2 of the present invention is obtained by replacing the "adsorbing plate" with "magnet" and the "magnet" with "adsorbing plate". Therefore, the same operation and effect as those of the first aspect are obtained.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the structure and operation of the present invention described above, a preferred embodiment of the gas valve opening / closing device of the present invention will be described below. FIG. 1 is a schematic diagram of a gas water heater as one embodiment. In the water supply path from the water inlet, a faucet 19 that opens and closes the flow path by manual operation using a push button 17 is provided, and the hydraulic pressure responsive device 1 is provided downstream thereof. The hydraulic pressure responsive device 1 is provided with a diaphragm 15 which is movable back and forth.
And a primary chamber 13 and a secondary chamber 12 are formed. A water governor 16 is provided coaxially with the diaphragm 15 at the entrance to the primary chamber 13 of the hydraulic pressure responsive device 1 to keep the flow rate constant even when the supply water pressure fluctuates. Also, Primary Room 1
A hot water temperature control unit 18 is provided in the flow path continuing from 3. The hot water temperature controller 18 branches the flow path in two directions, passes through a venturi 22 to a heat exchanger 23, and then mixes the water with a mixing unit 21.
And a bypass path 20 directly leading to the mixing section 21. Then, the branched flow paths merge at the mixing section 21 to reach a tap.

The venturi 2 provided in the heating path 28
Numeral 2 narrows the flow path and is provided with a horizontal hole in a direction perpendicular to the flow path and communicates with the secondary chamber 12 of the hydraulic pressure responsive device 1. When the water is passed to the venturi 22, the pressure in the secondary chamber 12 decreases in accordance with the decrease in the water pressure in the lateral hole due to the venturi effect. Accordingly, a differential pressure is generated between the primary chamber 13 and the secondary chamber 12, and a displacement force (to the left in the drawing) is generated in the diaphragm 15 that can be moved back and forth. A push shaft 14 for transmitting displacement and the spindle 3 are provided on the diaphragm 15 so as to abut on the same axis, and the other end of the spindle 3 is provided with an automatic water supply gas valve 4. The automatic water supply gas valve 4 is urged by a valve spring 5 so as to close in the downstream direction of the gas flow path. When water is supplied, the displacement force of the diaphragm 15 overcomes the force of the valve spring 5 to open the gas flow path.

In the gas supply path to the burner 27, an instrument plug 25 for opening and closing the gas passage by manual operation of the push button 17 is provided. Further, the valve is opened downstream by the interlocking of a manual operation, and is kept open by the thermoelectromotive force of a thermocouple (not shown) during combustion. A magnetic safety valve 26 is provided to valve. The burner 27 is provided with an electrode (not shown) for igniting a gas by discharge.

On the axis of the spindle 3, cylindrical magnets 2 (permanent magnets) provided with an attracting surface in the direction in which the spindle 3 retreats (right side in the figure) are fixed by E-rings 31 and 32. A ring-shaped suction plate 6 having a larger diameter than the magnet 2 is slidably inserted into the spindle 3 so as to face the suction surface of the magnet 2. The suction plate 6 is provided in the direction in which the spindle 3 moves backward with respect to the magnet 2 (right side in the figure). In order to prevent dust and dirt from adhering to the suction surface, a cylindrical cover 30 for storing the magnet 2 and the suction plate 6 is provided, and the magnet 2 and the suction plate 6 are movably covered and fixed to the gas flow path. On the inner wall surface of the cover 30, an engaging portion 8 for reducing the diameter of the inner wall to form a step on the inner wall is provided. The position of the locking portion 8 is provided at a position where only the suction plate 6 is locked immediately before the automatic water supply gas valve 4 is opened, and the movement of the suction plate 6 in the valve opening direction is prevented. Also, the suction plate 6
Is biased by a spring 33 toward the locking portion 8.

Next, the operation of the automatic water supply water gas valve 4 will be described with reference to FIG. (A) shows the closed state of the automatic water supply gas valve 4. At this time, the suction plate 6 is urged by the spring 33 and is attracted to the magnet 2. When the flowing water pressure rises from this stopped state, the hydraulic pressure responsive device 1 operates, and the spindle 3 moves forward (to the left in the figure). Further, the magnet 2 fixed to the spindle 3 moves while being attracted to the attracting plate 6. Then, when the water supply automatic gas valve 4 reaches the position immediately before opening, that is, the E-ring 35 provided on the spindle 3 abuts on the water supply automatic gas valve 4 to start the valve opening (specifically, the E-ring 35). Is a water supply automatic gas valve 4
Is started, but when the water supply automatic gas valve 4 reaches a position where the automatic water supply gas valve 4 is not opened due to the elastic interference in the valve portion of the automatic water supply gas valve 4), the suction plate 6 engages with the locking portion 8 (B). When the flowing water pressure further rises from this state and the flowing water pressure overcomes the attraction force between the magnet 2 and the attraction plate 6, the magnet 2 is detached from the attraction plate 6. At this time, the suction force that prevented the forward movement of the spindle 3 is released by the separation, and the flowing water pressure becomes superior, and the water supply automatic gas valve 4 at a stroke until the gas amount necessary for ignition can be secured (H1 dimension).
(C). In this way, the fuel gas from the gas inlet is supplied through a route from the instrument plug 25, the magnet-type safety valve 26, the automatic water supply gas valve 4, and the burner 27 (FIG. 1), and is supplied to the gas flowing in by the discharge of the igniter (not shown). It ignites and the burner 27 starts burning. Further, the automatic feed water gas valve 4 moves with the rise of the flowing water pressure, and the opening degree of the automatic feed water gas valve 4 is fully opened (d).

In this state, when a water supply tap (not shown) is closed, the water supply pressure decreases, the spindle 3 moves backward (to the right in the figure), and the automatic water supply gas valve 4 moves in the valve closing direction. And
When the water supply automatic gas valve 4 reaches the minimum opening (H2 dimension) for securing the amount of gas that can be burned, the magnet 2 moves to the adsorbing plate 6
The spindle 3 is moved by the adsorbing force to adsorb the water, and the water supply automatic gas valve 4 is closed all at once to the valve closing position (b). When the flowing water pressure further decreases, the return spring 11
The spindle 3 returns to the stopped state by the force (a).

Next, FIG. 3 shows the load characteristics with respect to the stroke of the spindle 3, and the opening / closing operation of the automatic water supply gas valve 4 will be described. In the drawing, o → q → m → j indicates load characteristics of the valve spring 5 applied to the spindle 3 during the stroke of the spindle 3. Also, as described later, e to f indicate the attraction force when the attraction plate 6 and the magnet 2 are separated. In the following description, the term “water pressure” is simply the pushing force of the spindle 3 obtained by subtracting the force of the return spring 11 acting in the opposite direction from the pushing force of the hydraulic pressure responsive device 1. Further, the "close-off zone" in the figure means that even if the automatic water supply gas valve 4 starts moving in the valve opening direction by the spindle 3, the gas valve portion of the automatic water supply gas valve 4 has elasticity. Since it is made of a material, it refers to a range in which gas does not leak. The “non-ignition zone” (point n to point p) refers to the opening range of the automatic feed water gas valve 4 in which an ignition error occurs due to an insufficient amount of gas at the time of ignition. In addition, "flame disappearance zone"
The term (v-point to n-point) refers to the opening range of the automatic water supply gas valve 4 in which the flame disappears due to an insufficient amount of gas during combustion. Usually, the range of the “flame disappearance zone” is smaller than that of the “non-ignition zone” due to the flame holding effect of the burner (the characteristic that it is difficult to extinguish the fire once it is ignited).

In the stop state without flowing water pressure, the spindle 3
Is in the retracted position (FIG. 2A). In addition, spindle 3
The magnet 2 moving integrally with the spindle 3
Is attracted to the suction plate 6 at the position where the arm is retracted. Then, when the flowing water pressure rises from this stopped state,
The spindle 3 moves forward. In this position, the load of the valve spring 5 does not affect the advance of the spindle (point o → point q in FIG. 3). When the flowing water pressure further rises, the E-ring 35 provided on the spindle 3 causes the automatic water valve for water supply. 4 and automatic water supply gas valve 4
(Fig. 2 (b)). However, even if the load of the valve spring 5 is transmitted to the spindle, the spindle 3 cannot move until the pushing force by the flowing water pressure reaches the load of the valve spring 5 (point q → point m). When the pushing force by the flowing water pressure exceeds the load of the valve spring 5, the valve spring 5 starts to be compressed (point m → point e). When this point e is reached, the locking portion 8 locks the suction plate 6 and the suction force between the magnet 2 and the suction plate 6 causes the spindle 3 to move.
Prevent movement. That is, the load (point e) of the valve spring 5
Then, the attracting force of the magnet 2 (difference between the points e and f) is added to prevent the spindle 3 from being moved until the flowing water pressure rises to a pushing load of the point f or more. Then, when the flowing water pressure increases to a pushing load exceeding the point f, the flowing water pressure overcomes and the magnet 2 is separated from the attraction plate 6. Then, the movement of the spindle 3 due to the attraction force is instantaneously eliminated, and the flowing water pressure is increased by the amount at which the attraction force is lost. Move (point f → point e → point g). Therefore, the feed water automatic gas valve 4 is provided in the non-ignition zone (n-point to
(P point) quickly, the opening (H
The valve is opened in 1) (FIG. 2 (c)). When the water supply automatic gas valve 4 is opened, the gas flows into the burner 27 and is ignited by the discharge of an igniter (not shown) to start combustion. Further, the valve spring 5 is compressed according to the rise of the flowing water pressure, the opening degree of the automatic water supply gas valve 4 is widened, and the load of the valve spring 5 is j.
Point (point g → point j) and continue burning (FIG. 2).
(D)).

On the other hand, when the flowing water pressure decreases from the steady combustion state (point j), the spindle 3 starts to retreat (point j → point j).
g point), the automatic feed water gas valve 4 is moved in the valve closing direction. Then, when the water supply automatic gas valve 4 reaches the minimum opening (H2) for securing the amount of gas that can be burned (FIG. 2C), the magnet 3 and the suction plate 6 attract the spindle 3 by the attraction force. Move all at once to the valve closing position (point w → f
Point), the magnet 2 and the adsorption plate 6 are adsorbed, and the water supply automatic gas valve 4 is closed (FIG. 2B). Therefore, the feed water automatic gas valve 4 is connected to the flame disappearance zone (points v to n
Point) and extinguish the fire immediately without releasing raw gas. When the flowing water pressure further decreases, the spindle 3 returns to the stopped state by the force of the return spring 11 (point f → e).
Point → m point → q point → o point) (a).

As described above, the automatic feed water gas valve 4 according to the present embodiment opens or closes instantly when the flow pressure reaches a predetermined flow pressure as the flow pressure rises or falls. Therefore, when the water supply automatic gas valve 4 is opened, the valve is not opened at a halfway opening, the required opening is secured, and ignition can be performed with a sufficient amount of gas. And release of raw gas can be eliminated. In addition, when the water supply automatic gas valve 4 is closed, the valve is not closed at a halfway opening, but can be closed instantaneously from a sufficient opening, so that the flame disappears due to an insufficient gas amount. It does not happen
Emission of raw gas during the valve closing process can be eliminated. Further, since no raw gas is emitted, there is no explosive ignition caused by the re-ignition operation.

Further, by changing the attraction force between the magnet and the attraction plate and the position of the locking portion, the required degree of opening can be freely set. Therefore, as described in the conventional example, the result of changing the plate-like leaf spring, changing the stroke of the spindle, or increasing the seat diameter of the automatic water supply gas valve for the purpose of changing the opening of the automatic water supply gas valve at the time of ignition. However, there are no major changes and no reduction in size is sacrificed. Therefore, it is possible to easily set an appropriate opening degree according to a device having a different gas consumption and a calorific value of a gas to be used.

Further, in order to change the attraction force between the magnet and the attraction plate, a groove can be formed in the attraction surface to change the attraction area. Therefore, the required opening degree can be appropriately set depending on the gas type, and the amount of gas at the time of ignition can be set more easily according to the gas type. As a result, it is possible to easily provide a water supply automatic gas valve having not only a function of preventing raw gas emission at the time of opening and closing but also a function of slow ignition for smoothly igniting.

In order to close the valve by moving quickly and smoothly to the position where the flowing water pressure and the spring load are balanced, instead of closing the valve automatically when the valve is closed, No excessive force is applied to the seat of the automatic gas valve,
The durability is improved.

As described above, the water supply automatic gas valve 4 shown in the present embodiment does not use an expensive plate-like leaf spring that performs a snap operation, and can easily provide an appropriate opening degree by using a structure using an inexpensive magnet. It is possible to obtain an inexpensive and highly safe gas valve opening / closing device.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments at all, and can be implemented in various modes without departing from the gist of the present invention. Of course. For example, the present invention is not limited to manufacturing only a magnet with a permanent magnet (magnetic material), and the same operation and effect can be obtained by manufacturing both or one of the magnet and the attraction plate with a permanent magnet (magnetic material). . Moreover, when both the magnet and the attracting plate are permanent magnets, a strong attracting force can be set. Therefore,
The opening setting can be freely selected from small to large, and appropriate settings can be made according to the devices with different gas consumption and the calorific value of the gas used.

In the embodiment, a magnet, an attraction plate,
Although the suction plate, the locking portion, and the spring have been described as being incorporated in the spindle in the gas flow path, they may be incorporated in a spindle outside the gas flow path that communicates from inside the flow path.

Further, in the embodiment, the locking portion is provided on the inner wall surface of the cover 30. However, the locking portion may be formed directly on the gas flow path wall without providing the cover 30.

[0025]

As described in detail above, claim 1 of the present invention
According to the gas valve opening / closing device described in (2) and (3), the automatic water supply water gas valve can be instantaneously opened to a predetermined opening degree and can be instantly closed from the predetermined opening degree. Further, the automatic water supply gas valve can be closed instantaneously from a predetermined opening degree. Therefore, when the flowing water pressure is low, or even when the flowing water pressure has an unstable fluctuation that cannot completely open and close the automatic water supply gas valve, halfway opening and closing cannot be performed and reliable opening and closing can be performed instantaneously. Therefore, there is no temporary raw gas release due to misfire,
Safety can be improved. In addition, since the degree of opening of the automatic feed water gas valve can be easily set, the mode of ignition can be set appropriately, and the mild ignition that smoothly ignites can be appropriately performed according to the equipment having different gas consumption and the calorific value of the gas used. Can be set, and safety can be further improved. Further, by using an inexpensive magnet, the gas valve opening / closing device can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic view of a gas valve opening / closing device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing the operation of the automatic water supply gas valve according to the embodiment of the present invention.

FIG. 3 is a graph showing a relationship between a load and a stroke according to the embodiment of the present invention.

FIG. 4 is a schematic view of a conventional gas valve opening / closing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Water pressure response device 2 ... Magnet 3 ... Spindle 4 ... Automatic water supply gas valve 5 ... Valve spring 6 ... Suction plate 8 ... Locking part

Claims (2)

[Claims] 1. A gas valve opening / closing apparatus comprising: a spindle which moves forward and backward in response to a flowing water pressure; and a water supply automatic gas valve which opens and closes a gas flow path in conjunction with the spindle. A permanent magnet fixed to the spindle. When the suction plate which is loosely inserted into the spindle from the magnet and is attracted to the magnet, and the spindle which advances with increasing flowing water pressure reaches a position immediately before opening of the water supply automatic gas valve. A locking portion that locks the suction plate adsorbed on the magnet to prevent the spindle from moving forward, and the spindle that advances with increasing flowing water pressure opens the water supply automatic gas valve. When the water pressure reaches the position just before the valve and the flowing water pressure reaches a water pressure that can be opened to a sufficient degree for ignition, the magnet and the adsorbing plate are separated and the water supply automatic gas valve is opened. And, when the spindle, which retreats as the flowing water pressure decreases, reaches a predetermined opening position of the automatic water supply gas valve, the magnet is attracted to the suction plate, and the automatic supply water gas valve is closed. A gas valve opening / closing apparatus, wherein an attraction force between the magnet and the attraction plate is set. 2. A gas valve opening / closing device comprising: a spindle which moves forward and backward in response to flowing water pressure; and an automatic water valve for water supply which opens and closes a gas flow path in conjunction with the spindle, wherein an adsorbing plate fixed to the spindle; The spindle is loosely inserted in the retracting direction from the suction plate,
A magnet of a permanent magnet that is attracted to the attraction plate, and the magnet that is attracted to the attraction plate when the spindle that advances with an increase in flowing water pressure reaches a position immediately before the water supply automatic gas valve is opened. And a stopping portion for stopping the spindle from moving forward is provided, and the spindle moving forward with the rise of the flowing water pressure reaches a position immediately before the water supply automatic gas valve is opened, and the flowing water pressure is sufficient for ignition. When the water pressure that can be opened to a certain degree of opening is reached, the adsorbing plate and the magnet are separated and the water supply automatic gas valve is opened, and the spindle that retreats with a drop in flowing water pressure is the above-mentioned spindle. When the water supply automatic gas valve reaches a predetermined opening position, the suction force between the suction plate and the magnet is set so that the suction plate is attracted to the magnet and closes the water supply automatic gas valve. Did A gas valve opening and closing device.