JPH0217778B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to gas instantaneous water heaters and other gas appliances.

(Prior art) A thermocouple and an igniter are placed in front of a burner, and the igniter is provided with an ignition circuit that provides a spark discharge to the igniter for the charging or discharging time of a first capacitor that is charged by a battery power source. , a coil of a solenoid valve facing the gas supply path of the burner, which is held open by the electromotive force of the thermocouple, is interposed in a discharge circuit of a second capacitor charged by the battery power source, so that the solenoid valve is connected to the A combustion control device in which the valve is forcibly kept open by the discharge of the second capacitor is disclosed in, for example, Japanese Utility Model Application Publication No. 128363/1983.

In such cases, the release of raw gas can be prevented by setting the duration of the spark discharge in the igniter to be longer than the forced hold time of the solenoid valve, which is held open by the discharge of the second capacitor. desired in doing so.

Therefore, even if the setting times of both are set according to such wishes, the charging characteristics of the first capacitor shown in FIG. 9 and the discharging characteristics of the second capacitor shown in FIG. Therefore, even if the voltage is set as shown in A and B in Figures 8 and 9 when the rated voltage is set, if the voltage drops due to battery power consumption, the time difference between the two will be as shown in C and D. decrease,
Eventually, as shown in EF, the situation is reversed and the operating time of the igniter becomes shorter than the forced hold time of the solenoid valve.

This means that even though the electromagnetic safety valve is held open by the second capacitor and combustion gas is being released from the burner, there is a period in which there is no spark discharge, and there is a risk of raw gas being released. . Conventionally, therefore, the battery is replaced at the time of this reversal, but the battery is in a fully usable state at this time, which is uneconomical. This also occurs due to variations in the withdrawal current values of the first and second capacitors or the solenoid valves.

(Problems to be Solved by the Invention) The present invention aims to shorten as much as possible the difference between the activation time of the igniter and the forced hold time of the solenoid valve by the second capacitor even when such a situation occurs. The object of the present invention is to provide a device that eliminates the above-mentioned disadvantages.

(Means for Solving the Problems) The present invention provides a burner with a thermocouple and an igniter, and a thermocouple and an igniter that are connected to the igniter for a period of time for charging or discharging a first capacitor that is charged by a battery power source. an ignition circuit that obtains a spark discharge; and a coil of an electromagnetic valve facing the gas supply path of the burner, which is held open by the electromotive force of the thermocouple, to a discharge circuit of the second capacitor that is charged by the battery power source. The electromagnetic valve is forcibly held open by the discharge of the second capacitor, and is further switched from the starting position to the intermediate opening position and then to the final ignition position. Between the starting end position of the operating rod and the ignition position, the switch that intervenes in the ignition circuit and the discharge circuit can be switched to the side that closes these circuits, and the second capacitor is connected to the ignition position. A sub-discharge circuit is provided which is closed in conjunction with the return operation of the operating rod to the intermediate position.

(Example) An example of implementing the present invention will be described with reference to an instantaneous water heater.

In the drawings, reference numeral 1 indicates a heat exchanger, and reference numeral 2 indicates a burner unit opposite thereto.The burner unit 2 is composed of a main burner 2a, an ignition burner 2b, and a permanent burner 2c.

3 indicates a gas control section that controls fuel gas to the burner unit 2; 4 indicates a water control section that controls water flow to the heat exchanger 1; the gas control section 3 is a gas supply path connected to the burner unit 2; 5, and an electromagnetic safety valve 7 provided upstream of the isolation valve 6.
and an ignition burner 2b branching from the downstream side of the shutoff valve 6.
The shutoff valve 6 and the ignition valve 9 are provided on the same valve rod 10, and the electromagnetic safety valve 7 is connected to the constant flame burner 2c as described later. The valve is held open by the electromotive force of the thermocouple 11 and the discharge of the capacitor 13 facing the forced hold circuit 12. Reference numerals 14 and 15 indicate operating rods facing the front of both the control units 3 and 4, and the operating rods 14 and 15 are equipped with a push button mechanism 16,
An intermediate valve opening position C from the starting end position A and the valve opening position C
The push button 17 is then operated to switch to the final ignition position B.

To explain this, according to the first push of the push button 17, the operating rod 14 returns to the spring 18.
The ignition valve 9 opens first, and when the shutoff valve 6 opens at the intermediate opening position and is pressed to the final ignition position, the electromagnetic safety valve 7 is pressed and opened via the lever 19. let

When the push button 17 is released, the push button 17 is held at the open position where the intermediate shutoff valve 6 is held open by the push button 16.
At this time, the electromagnetic safety valve 7 is held open by the discharge of the capacitor 13 intervening in the forced hold circuit 12 and the electromotive force of the thermocouple 11. This releases the button 17 from the valve open position.
The configuration up to now is not particularly different from what is conventionally known.

The water control section 4 is composed of a water valve 21 in a water channel 20 connected to the heat exchange section 1, and when the push button 17 is pressed for the first time, the operating rod 15 moves backward against the spring 22, and the water valve 21 is connected to the heat exchange section 1. Ratchet 23 on operating rod 15
is engaged with the tip of the push lever 24 behind it, and when the push button 17 is subsequently released from the push, the operating rod 15 is moved back by the spring 22, so that the lever 24 is tilted via the ratchet 23. The water valve 21 behind it is opened.

This state is clearly shown in FIGS. 2 to 5, for example, and when the push button 17 is pressed a second time, the operating rod 15 once moves back a little and then returns to the starting position. Fifth, the ratchet 23 is tilted when it hits a stopper 25 in front of it and is disengaged from the lever 24.
As shown in the figure.

In the drawing, 26 is a hydraulic response member provided downstream of the water valve 21 of the waterway 20, and 27 is a hydraulic response member provided downstream of the cutoff valve 6 of the gas supply path 5, which is opened and closed in conjunction with the hydraulic response member 26. valve, 28 is ignition burner 2
This is the igniter shown in b.

FIG. 6 shows the operating circuit 29 of the igniter 28 and the forced hold circuit 12 of the electromagnetic safety valve 7. A charging circuit 33 for the first capacitor 32 and a discharging circuit 34 for the first capacitor 32 forming a closed circuit via the b contact 31b of the changeover switch 31,
In addition, a relay 35 is inserted into the charging circuit 33, and the relay contact 35a of the relay 35 is connected to the battery power source 3.
0 and the igniter 28, the relay 35 is energized until the current value flowing through the charging circuit 33 decreases to a certain value, while the relay contact 35a is closed to discharge a spark to the igniter 28. The forced hold circuit 12 connects the battery power source 30 and the b contact 37 of the changeover switch 37.
The second capacitor 13 is connected to the coil 7a of the electromagnetic safety valve 7 via the a contact 37a of the changeover switch 37.
It further includes a sub-discharge circuit 39 that intervenes in parallel with the discharging circuit 38, and a switch 40 that closes in conjunction with the return operation of the operating rod 14 to the intermediate position. I intervened.
In the drawing, 41 and 42 are resistors that intervene in the charging circuit 33 of the first capacitor 32 and the discharging circuit 38 of the second capacitor 13 to set the time constants of these circuits 33 and 38. 31 and 37 are switched to the a contact side by a cam 43 provided on the operating rod 14 between the intermediate starting end position and the final ignition position of the operating rod 14, and further intervened in the auxiliary discharge circuit 39. The switch 40 is configured to close in conjunction with the opening operation of the hydraulically responsive valve 27, which operates in conjunction with the operation of the operating rod 14 returning to the valve open position. However, it goes without saying that this can be closed by means such as interlocking with the operating rod 14.

The circuit shown in FIG. 7 is constructed so that the second capacitor 13 is also inserted into the charging circuit side of the circuit shown in FIG. When switched, a current of opposite polarity to the starting force of the thermocouple 11 is sent to the coil 7.
a, the electromotive force of the thermocouple 11 can be canceled and the electromagnetic safety valve 7 can be closed more quickly.

(Function) In this case, as described above, the time required for the current value of the charging circuit 33 of the first capacitor 32 to decrease to a constant value is the time required for the current value of the discharge circuit of the second capacitor 13 to decrease to a constant value. Even if the capacitors 32 and 13 are provided for a longer period of time, the charging and discharging characteristics of both capacitors 32 and 13 are different as shown in FIGS. Time and forced hold circuit 1
2 and the hold time of the electromagnetic safety valve 7 decreases, and eventually shows a tendency to reverse.

However, when the auxiliary discharge circuit 39 is provided in the forced hold circuit 12 as described above, the discharge of the second capacitor 13 is accelerated as shown by G in FIG. According to this, when the voltage of the battery power source 30 drops compared to the conventional one, and the decay time of the discharge current of both capacitors 13 and 32 to the withdrawal current value is reversed. However, the decay time of the discharge current of the second capacitor 13 to the separation current value can be made as close as possible to that of the first capacitor 32. Furthermore, this is the first point.
The same applies even when a reversal occurs in the time it takes to reach a constant current value between the first capacitor and the second capacitor due to variations in the second capacitor or variations in the withdrawal current value of the solenoid valve. be. It is desirable to interpose a resistor 44 in the auxiliary discharge circuit 39 as well. In this case, the discharge from the auxiliary discharge circuit 39 can be delayed to some extent. Accordingly, as shown in FIG. , even if you let go of the push button 17 in 2 seconds and the operating rod 14 returns to the intermediate valve opening position, the second
The electromotive force X caused by the thermocouple 11 is added to the discharge current Y of the capacitor 13, and the resultant current value Z can be kept above the withdrawal current value to keep the electromagnetic safety valve 7 open, and the air purge time can be Even if it takes 7 seconds to ignite the ignition for some reason, after which the ignition is confirmed, the push button 17 is released, and the operating rod 14 returns to the intermediate position, the thermocouple 11 is still heated by the flame. As shown in FIG. 11, the composite current value Z can be maintained above the withdrawal current value in the same manner as described above.

By using a small capacitance first capacitor 32, the discharge time is shortened, and it is possible to prepare for a relatively quick re-ignition operation.

(Effect) According to the present invention, the thermocouple and the igniter are placed in front of the burner, and the igniter generates a spark for the charging or discharging time of the first capacitor that is charged by the battery power source. An ignition circuit for obtaining discharge and a coil of a solenoid valve facing the gas supply path of the burner, which is held open by the electromotive force of the thermoelectric body, are interposed in the discharge circuit of the second capacitor charged by the battery power source. so that the solenoid valve is forcibly held open by the discharge of the second capacitor, and is further switched from the starting position to the intermediate opening position and then to the final ignition position. In the device that intervenes in the ignition circuit and the discharge circuit between the starting end position of the rod and the ignition position, the second capacitor is closed in conjunction with the return operation of the operating rod to the intermediate position. By providing an auxiliary discharge circuit, the reduction time for the discharge current value to a constant current value after the operation lever of the second capacitor returns to the intermediate position is accelerated, and when the voltage of the battery power source drops, Even if the first capacitor discharges or the current flowing through the charging circuit decreases to a constant current value, it is possible to approach the reduction time as much as possible to prevent battery consumption or the first capacitor, second capacitor, or solenoid valve. Even if the time for the current value in the charging or discharging circuit of the first capacitor to decrease to a constant value due to variations in the withdrawal current value etc. is faster than the time for the current value in the discharging circuit for the second capacitor to decrease to a constant value, This has the effect of making the reduction time of the current flowing through the discharging or charging circuit of the first capacitor to a constant current value close to that of the second capacitor, thereby preventing the release of raw gas as much as possible.

[Brief explanation of drawings]

FIG. 1 is a cutaway plan view of an example of a water heater showing an example of the implementation of the present invention, FIGS. 2 to 5 are plan views of the pressing lever portion, FIGS. 6 and 7 are electric circuit diagrams, FIGS. 8 to 11 are characteristic curve diagrams. 1...Heat exchanger, 2...Burner unit, 7...
...Electromagnetic safety valve, 11...Thermocouple, 13...Second capacitor, 30...Battery power supply, 32...First capacitor, 39...Sub discharge circuit.

Claims (1)

[Claims] 1. A thermocouple and an igniter are placed in front of the burner, and an ignition circuit is provided on the igniter to provide a spark discharge to the igniter for the charging or discharging time of a first capacitor that is charged by a battery power source, and the thermocouple is connected to the igniter. A coil of a solenoid valve facing the gas supply path of the burner, which is held open by an electromotive force of between the starting end position of the operating rod and the ignition position, in which the valve is forcibly held open by the discharge of the operating rod, and is further operated to switch from the starting end position to the final ignition position via an intermediate valve opening position, In the device in which the switch that intervenes in the ignition circuit and the discharge circuit can be switched to the side that closes these circuits, the second capacitor is connected to the second capacitor in conjunction with the return operation of the operating lever to the intermediate position. A combustion control device comprising a sub-discharge circuit that is closed by