JPS6350611B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a combustion control device for a gas instantaneous water heater, in which gas combustion automatically starts when water, which is an object to be heated, is passed through, and when water stops flowing, combustion starts. It is also a control device that automatically stops.

In simple instantaneous water heaters, water was passed after the pilot burner was ignited, and main combustion was started by opening the main burner with a water pressure valve. It was inconvenient that it required manual operation. For this reason, there is a demand for water heaters that automatically start combustion just by passing water through them, and are being implemented especially when the main body is installed outdoors or otherwise away from the place where the hot water is used.

FIG. 1 is a typical example of a conventional method used for this purpose. That is, the first solenoid valve 3 and the second solenoid valve are installed in the middle of the main pipe line 2 that supplies gas to the main burner 1.
Solenoid valves 4 are provided in series, and a pilot pipe line 6 leading to a pilot burner 5 is branched from the middle of both solenoid valves. On the other hand, a water flow detector 8 having a diaphragm, a float, etc. that converts water flow into mechanical displacement is provided in the middle of the water channel 7, and a heat exchanger 9 heated by the main burner 1 is also provided. . A contact signal from a switch 10 activated by the water flow detector 8 and an electromotive force signal from a thermocouple 11 heated by the pilot burner 5 are sent to a controller 12. Although not shown, the controller 12 is powered by commercial power, and the appliance can be used by turning on the power.

The operation in this example is as follows. When water flows, the water flow detector 8 switches the contact point of the switch 10, and the controller 12 switches the first solenoid valve 3.
When opened, an igniter (not shown) is started to ignite the pilot burner 5. Eventually, when the electromotive force of the thermocouple 11 exceeds a certain value or the increasing tendency of the electromotive force reaches a predetermined value, the controller 12 also opens the second solenoid valve 4 to cause combustion in the main burner 1 and stop the igniter. When the faucet is closed on the upstream or downstream side of the water channel 7, the switch 10 returns to its original state, and the controller 12 closes both electromagnetic valves to stop combustion. Of course, if the electromotive force signal is not obtained even after a certain period of time has passed after opening the first solenoid valve 3, or if the electromotive force signal disappears due to a misfire of the pilot burner 5, 1 has a safety function of automatically closing the solenoid valve 3. or,
A flame rod may be used instead of the thermocouple 11.

In this way, gas instant water heaters that automatically start and stop combustion simply by opening and closing the faucet are widely used.
Since it requires commercial power, there was a problem that it could not be used during a power outage. Furthermore, in the case of outdoor equipment, an outdoor outlet with waterproof measures is required, and if there is no outdoor outlet, it is necessary to perform new electrical work, which is a constraint on equipment construction. Furthermore, water heaters integrated with the bathtub require careful considerations such as low voltage and double insulation for safety reasons, making them expensive.

In view of the above points, the present invention aims to provide a combustion control device for a water heater that can automatically start and stop combustion by simply opening and closing water flow without using a commercial power source.

In other words, the main valve and pressure-responsive valve are installed from the upstream side leading to the main burner, the pilot valve is installed in the middle of the pilot pipe that branches from the middle between the main valve and the pressure-responsive valve and reaches the pilot burner, and the pilot burner It has a thermocouple that is heated, an operation switch that is linked to the opening and closing of the main valve, an igniter, and a battery.After the operation switch is activated, the power is turned on for a while, and then the battery output turns off the igniter and pilot valve. At the same time, thermoelectromotive force is also supplied to the pilot valve, and the pressure-responsive valve is activated by pressure changes in the pilot pipe, and the main valve is composed of a hydraulically-responsive valve that opens and closes when water flows through it. Then, when water is supplied, the main valve opens, the operating switch changes, the pilot valve opens, and at the same time the igniter starts, the pilot burner ignites, and the pilot valve maintains its open state due to thermoelectromotive force. At the same time, the pressure in the pilot pipe changes, so the pressure-responsive valve also opens and combustion begins in the main burner. In this way, after the pilot valve is temporarily opened by battery output, it is maintained by thermoelectromotive force, and the pressure-responsive valve is opened indirectly, allowing only water to flow without using commercial power. This allows combustion to start and stop.

Next, a detailed explanation will be given based on examples of the present invention. FIG. 2 is a circuit configuration diagram of gas, water, and electricity in an example in which the present invention is applied to a gas instantaneous water heater. Here, a main pipe 102 leading gas to the main burner 101 includes a main valve 103 and a pressure-responsive valve 1 from the upstream side.
04 is inserted, and a pilot pipe 106 leading to a pilot burner 105 from between these two valves.
is branched, and a pilot valve 107 is inserted in the middle. An orifice 108 is provided in the pilot pipe 106 on the upstream side of the pilot valve 107, and the pressure between the orifice 108 and the pilot valve 107 acts on the pressure-responsive valve 104. and,
As explained in detail in FIG.
The pressure-responsive valve 104 is integrated with the pressure-responsive valve 104 to form a pilot-type diaphragm valve 1.
It says 09.

On the other hand, water flows into the water pressure response section 1 in the middle of the water passage 110.
11 is provided and then heated in a heat exchanger 112. The water pressure response unit 111 receives the water flow differential pressure through a diaphragm and uses the force to mechanically open the main valve 103, which is a conventionally known method and will not be described in detail.
Also, when the main valve 103 opens, the operation switch 11
This is also configured to be mechanically interlocked to open 3. That is, by passing water, the main valve 103 is opened and the operation switch 113 is switched, and when the water supply is stopped, the main valve 103 is closed and the operation switch 113 is also returned to its original state.

Next, the electrical circuit will be explained. 114
is a thermocouple heated by the pilot burner 105, and its output is supplied to the first coil 115 of the pilot valve 107. Operation switch 11
3 connects the battery 116 to the capacitor 117 when water is not flowing, and the capacitor 117 is charged. When the operation switch 113 is switched, the capacitor 117 discharges to the second coil 118 of the pilot valve 107 and the igniter 119,
For a while until the voltage drops below a predetermined value, the pilot valve 107 can be opened and a spark discharge can be generated between the electrodes 120 of the igniter 119. When the charge in the capacitor 117 is discharged, the igniter 119 is stopped and the power supply to the second coil 118 is also stopped. The operating time of the capacitor 117 can be arbitrarily changed depending on the capacitor capacity, but from the operation described later, the thermoelectromotive force is increased to a value that allows the pilot valve 107 to be kept open by the output of the thermocouple 114. It is necessary to set it depending on the time it takes to reach the target.

An example of the configuration of the pressure response 104 will be explained with reference to the sectional view of FIG. A valve seat 121 is placed in the valve housing in the middle of the main pipe 102, and is opened and closed by a valve rubber 123 integrated with a diaphragm 122, and a force in the closing direction is always applied by a spring 124. . It can be said that these elements constitute the pressure-responsive valve 104. The main pipeline 102 and the diaphragm back pressure chamber 12 pass through the center of the diaphragm 122 and are located upstream of the valve seat 121.
There is a pore connecting the two holes, which is the orifice 108. A pilot pipe 106 connects from the back pressure chamber 125 to a pilot burner via a pilot valve 107.
is connected. Now, when the pilot valve 107 is closed, even if the main valve 103 is opened, the gas pressure in the diaphragm back pressure chamber 125 is the same as that on the upstream side of the valve seat 121, so this gas pressure causes the diaphragm 122 to close in the closing direction. The force and the force of spring 124 keep the valve closed.

When the pilot valve 107 opens, the pilot pipe 10
6, the pressure drop at the orifice 108 rapidly increases and the pressure in the back pressure chamber 125 drops significantly. As a result, the force of the supply gas pressure applied to the inner diameter of the valve seat in the opening direction overcomes the force in the closing direction due to the gas pressure of the spring 124 and the back pressure chamber 125, and the valve rubber 123
moves upward in Figure 3. Then, when the supply gas pressure is applied to the entire lower surface of the diaphragm 122, the force in the opening direction increases more and more, so that the valve is completely opened. When the first pilot valve 107 is closed again, the pressure on both sides of the diaphragm 122 becomes equal through the orifice 108, so it moves in the closing direction by the force of the spring 124, and when the valve rubber 123 comes into contact with the valve seat 121, the gas in the opening direction is released. The force due to pressure suddenly decreases, so the valve returns to a completely closed state. In this manner, the embodiment shown in FIG. 3 forms a pilot-type diaphragm valve 109 in which the orifice 108 is also integrated.

FIG. 4 shows another embodiment of the electric circuit. Here, the charging energy of the capacitor 117 is applied to the relay coil 126 after the operation switch 113 is switched. Then, the relay contact 127 is turned on to supply power from the battery 116 to the igniter 119 and the second coil 118 of the pilot valve 107. Although this method requires a relay, the capacitance of the capacitor 117 can be set lower than in the embodiment shown in FIG.

Since the pilot valve 107 is opened by the output of the battery 116 and kept open by the output of the thermocouple 114, it must be operated with much lower power than a solenoid valve that uses a normal commercial power source.
An example of this will be explained with reference to a sectional view of a pilot valve in FIG. 5 and a perspective view of a magnetic circuit in FIG. The valve housing consists of an upper case 128 and a lower case 129, in which gas flows from an inlet 130 through a chamber 131 to an outlet 132. A valve seat 13 is provided on the chamber 131 side of the outlet 132.
3 is formed. Parallel fixed iron cores 134 and 135 are placed in the chamber 131 and connected by a yoke 136 on the outside passing through the upper case 128 to form a U-shaped fixed side magnetic circuit 137. Opposed to this U-shaped movable core 1, which is also almost U-shaped.
38 is the leg part 139,140 is the fixed iron core 13
The free end 143 side is provided so as to be in contact with or detach from the flat surfaces 141, 142 of the iron cores 141, 142, and is normally directed away from the fixed iron cores 134, 135 by a spring 144 and in the direction mentioned above. The valve seat 133 is energized in the direction of approaching the valve seat 133. A valve piece 145 is provided at the free end 143 of the movable iron core 138, a force is applied in the direction of the valve seat 133 by a spring 146, and the valve piece 145 is prevented from coming off by a pin 147. Fixed iron cores 134 and 135 have circular portions 148 and 149 penetrating through the upper case 128, and are air-sealed with an O-ring 150. The yoke 136 has a first coil 115 and a second coil.
A coil 116 is wound. When the coil is energized, the free end 143 side of the movable iron core 138 is attracted to the fixed iron cores 134 and 135, and the valve piece 145 is separated from the valve seat 133 and becomes in an open state. In order to operate with low power and maintain the valve open state, it is desired that the magnetic circuit has a configuration that has low magnetic resistance and high attractive force not only in the closed state but also in the open state. In this regard, in the embodiment, even when the magnetic circuit is in an open state (the valve is closed), the flat surfaces 141 and 142 of the fixed cores 134 and 135 and the lower surface 151 of the movable core 138
are opposed over a wide area, the legs 139 and 140 are always in contact, and by providing the valve piece 136 at the free end 143, the gap of the magnetic circuit can be set smaller than the operating stroke of the valve. This is advantageous in reducing magnetic resistance. First coil 11
5 and the second coil 118 may be divided or wound in layers. However, the second coil 118 is used to open the valve from closed using the power of the battery 116, and the first coil 115 is used to maintain the valve open.
It is necessary to set the coil wire diameter and number of turns according to each power supply and required amperage turns. As in this embodiment, having the coil section outside the gas atmosphere not only improves safety but also has the effect of freeing space for the coil and making it easier to reduce power consumption.

Now, the operation of the combustion control of the present invention, which integrates the functions of the above-mentioned parts, is as follows. The main valve 103 opens due to water flow, and at the same time the operation switch 11
3 switches, the capacitor 117 that had been charging is discharged, and the pilot valve 10
7 is opened by excitation of the second coil 118. At the same time, a spark is generated at the ignition electrode 120 and the pilot burner 105 burns. When the pilot valve 107 opens, the differential pressure across the diaphragm 122 changes in the pressure-responsive valve 104, so it is opened and the main burner also starts combustion. Although the opening of the pilot valve 107 and the spark discharge are simultaneous, there is a slight delay in the opening of the pressure-responsive valve 104 until the force relationship at the diaphragm 122 is reversed. On the other hand, the voltage of the capacitor 117 decreases as it discharges, and the igniter 119 eventually stops, and the pilot valve 1
The power supply to the second coil 118 of 07 is also stopped. However, at this time, since the first coil 115 is excited by the output of the thermocouple 114, combustion continues. In this way, combustion can be started by simply opening the faucet and flowing water without operating the gas side.

In the unlikely event that an ignition error occurs, the first coil 115 will not be energized, and as soon as the capacitor 117 has finished discharging, the pilot valve 107 and the pressure-responsive valve 1 will be activated.
04 are both closed, so there will be no continued gas release after that. This is also on the safe side since the pilot valve 107 will not open from the beginning if the battery is exhausted. A superheat prevention fuse is inserted between the thermocouple 114 and the first coil 115 to connect the heat exchanger 112.
Of course, it is also possible to take the usual measures to protect the

Next, another embodiment of the pressure-responsive valve 104 will be described with reference to the sectional view of FIG. 7. A valve seat 201 is provided in a valve housing provided in the middle of the main pipe line 102, and is opened and closed by movement of a valve rubber 202 corresponding to the valve seat 201. Valve rubber 20 on the upstream side of valve seat 201
A balance diaphragm 203 having an effective area approximately equal to the area of the valve seat 201 is disposed on the opposite side from the valve seat 201, and partitions a lower chamber 205 of the main diaphragm 204 from the main conduit 102 side. The lower chamber 205 is connected to the main pipe 102 through an orifice 108 on the upstream side of the valve seat 201, and a pilot pipe 106 and a pilot valve 107 are connected on the downstream side.
The upper chamber 206 of the main diaphragm 204 communicates with the downstream side of the pilot valve 107, and a spring 207 therein presses the main diaphragm 204 toward the lower chamber. The valve rubber 202, the balance diaphragm 203, and the main diaphragm 204 are arranged on the same axis, and the three are coupled so as to be interlocked. Now, when the pilot valve 107 is closed, the lower chamber 205 is opened through the orifice 108.
Since the supply gas pressure is applied to the upper chamber 206 and the upper chamber 206 is open to the atmosphere, the force due to this pressure difference causes the valve rubber 202 to
is pressed against the valve seat 201. Next, when the pilot valve 107 opens, gas flows into the pilot pipe 106 and the pressure in the lower chamber 205 decreases due to the pressure drop caused by the orifice 108. On the other hand, the upper chamber 206
A gas pressure higher than atmospheric pressure is applied to the main diaphragm 204, and as a result, the force acting on the main diaphragm 204 in the closing direction is drastically reduced, and the valve is opened by the force of the spring 207.

That is, as in the embodiment shown in FIG. 3, the main pipe 102 can be opened and closed by opening and closing the pilot valve 107.

As explained above in detail based on the examples,
The operation switch 113, which is switched at the same time as the main valve 103 opens, temporarily supplies the power of the battery 116 to the igniter 119 and the pilot valve 107 to ignite the pilot burner 105, and the thermoelectric power heated by the pilot burner 105 is activated. The output of the pair 114 keeps the pilot valve 107 open, and the pilot pipe 1 into which the pilot valve 107 is inserted is
The pressure response valve 104 downstream of the main valve 103 is opened by the pressure change of 06, and combustion is started in the main burner 101. Therefore, the main valve 103 is opened by the flow of water, which is an object to be heated. With this configuration, combustion can be started and stopped simply by opening and closing a faucet without using a commercial power source.

According to the present invention, battery consumption can be reduced because the battery is used for a very short time immediately after water flow starts, and after the pilot valve is opened, the thermocouple output only maintains the valve open state. Therefore, there is no need to use a particularly high output thermocouple compared to conventional pilot safety array thermocouples. Also, although the main pipe is natural and the pipe diameter is large, it is an indirect method that opens and closes the pressure-responsive valve based on pressure changes in the pilot circuit, so the cost is much lower than when directly inserted into the main pipe as in the past. Electricity is fine. This was the reason why the combustion control device for a water heater of the present invention could be achieved even if the battery consumption was low. Furthermore, when the pilot valve opens after the operation switch is turned, the pressure-responsive valve immediately starts operating and combustion starts from the main burner as well, reducing the time it takes for hot water to rise after opening the faucet. However, it is also possible to immediately expel the air in gas piping, which is often found immediately after equipment is installed. When the water is turned off, the pilot burner is also turned off, which not only saves wasted gas, but also prevents overheating caused by the pilot burner.

[Brief explanation of drawings]

Figure 1 is a gas and water circuit configuration diagram of a conventional gas instantaneous water heater using a commercial power supply, and Figure 2 is a gas, water, and electricity circuit in a gas instantaneous water heater that is an embodiment of the present invention. 3 is a sectional view of the pressure-responsive valve used in FIG. 2, FIG. 4 is an electric circuit diagram of another embodiment of the present invention, and FIG. 5 is a sectional view of an embodiment of the pilot valve. , FIG. 6 is a perspective view of the magnetic circuit in the example of FIG. 5, and FIG. 7 is a sectional view showing another embodiment of the pressure-responsive valve. 101...Main burner, 102...Main pipe, 10
3...Main valve, 104...Pressure responsive valve, 105...
Pilot burner, 106...Pilot tube, 1
07... Pilot valve, 114... Thermocouple, 11
3...operation switch, 119...igniter, 116
...Battery, 111...Hydraulic pressure response unit, 117...Capacitor.

Claims (1)

[Scope of Claims] 1. A main valve and a pressure-responsive valve that are provided from the upstream side in the main pipe leading to the main burner and are activated by detecting water flow, and a branch from the main pipe between the main valve and the pressure-responsive valve. It has a pilot valve installed in the middle of the pilot pipe leading to the pilot burner, a thermocouple that is heated by the pilot burner, an operation switch that is linked to the opening and closing of the main valve, an igniter, and a battery. By operating the igniter and pilot valve with the battery output which is energized only for a short period of time, and also supplying the thermocouple output to the pilot valve, the pressure-responsive valve is operated by pressure changes in the pilot tube.
A water heater combustion control device that automatically starts and stops combustion by opening and closing the main valve. 2. The combustion control device for a water heater according to claim 1, wherein the main valve is opened and closed depending on the flow rate of the object to be heated.