JPH0942670A - Burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the safety by providing two systems of ignition detector for energizing a solenoid safety valve while a combustion flame is being detected. SOLUTION: If ignition detectors 81, 82 are normal in case that one of transistors 14, 15 is ON defective, the transistors 14, 15 of normal side can be turned OFF by the stops of ON signals 811, 821 at the time of unigniting or burner-flame failure. If the transistors 14, 15 are normal in the case that one of the detectors 81, 82 is ON defective (the state that ON signals 811, 821 are outputted when the combustion flame is not detected by a flame rod 800), either the transistor 14 or 15 can be turned OFF at the time of unigniting or burner-flame failure. Accordingly, the holding current of a holding coil 12 is cut OFF, a solenoid safety valve 1 is closed, and a gas burner is extinguished. If a water flow switch 4 is opened even if the one of the transistors 14, 15 is ON defective during using or one of the detectors 81, 82 is ON defective, the valve 1 can be closed, and it does not become impossible to extinguish a fire.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a combustion device.

[0002]

2. Description of the Related Art Conventionally, when an ignition instruction is issued by closing a solenoid valve arranged in a gas supply passage for supplying gas to a gas burner and a water flow switch, a predetermined time (for example, 0.
For 4 seconds), a suction holding circuit that energizes the solenoid valve, an ignition circuit that applies a high voltage to the ignition electrode according to an ignition instruction, a frame rod facing the gas burner, and ignition detection based on the output of the frame rod. A combustion device is known that includes an ignition detection circuit that sends an ON signal to a transistor electrically connected between a solenoid valve and a battery during detection.

[0003]

In the above combustion device, safety in case of misfire or misfire is maintained by the transistor and the ignition detection circuit. In the unlikely event that the ignition detection circuit fails the ON signal, the ON signal is sent to the transistor regardless of whether ignition has occurred.Also, even if the ignition detection circuit is normal, if the transistor fails to turn ON, current will flow to the solenoid valve regardless of whether ignition has occurred. Flowing. An object of the present invention is to provide a combustion device with improved safety.

[0004]

In order to solve the above problems, the present invention employs the following configurations. (1) A solenoid valve which is arranged in a gas supply path for supplying gas to a gas burner and whose valve body opens by energization, an ignition circuit which starts an ignition operation by an ignition instruction, and a combustion flame detection by an ignition instruction. In the combustion device including the safety circuit that starts and energizes the solenoid valve while the combustion flame is detected, two safety circuits are provided.

(2) A solenoid valve which is arranged in a gas supply passage for supplying gas to the gas burner and whose valve body opens by energization, a heat exchange passage having a heat exchange section heated by the gas burner, and one end A water flow switch whose contacts are closed when the side is connected to a battery and the water flow flowing through the heat exchange channel is detected.
A switch element electrically connected between the solenoid valve and the battery, an ignition circuit that starts an ignition operation when the water flow switch is closed, and a flame detection signal when a combustion flame is detected in the vicinity of the gas burner. In a combustion device comprising an ignition detection element for outputting and an ignition detection circuit for outputting an ON signal to the switch element while the ignition detection element is outputting the flame detection signal, the ignition detection circuit includes the flame. It has two independent discriminators that detect ignition based on the input of a detection signal, and a signal transmitter that outputs the ON signal when both discriminators detect ignition.

(3) A suction coil whose valve body opens by energization and a holding coil which maintains the valve open state by energization after suction are provided in a gas supply passage for supplying gas to the gas burner. A solenoid valve, a heat exchange channel having a heat exchange section heated by the gas burner, one end side of which is connected to a battery, and a water flow switch whose contacts are closed when a water flow flowing through the heat exchange channel is detected, A first switch element electrically connected between the suction coil and the battery; second and third switch elements electrically connected in series between the holding coil and the other end of the water flow switch; A suction timer circuit that is electrically connected to the other end of the switch and that outputs an ON signal to the first switch element for a predetermined time when operating power is supplied; and an ignition circuit that starts an ignition operation according to an ignition instruction. , The gas An ignition detection element that is arranged in the vicinity of the corner and outputs a flame detection signal when a combustion flame is detected, and an ON signal to the second and third switch elements while the ignition detection element is outputting the flame detection signal. And a first and second ignition detection circuit that outputs

[0007]

[Action]

[Claim 1] When an ignition instruction is issued, the solenoid valve is energized and the valve body opens. At the same time, the ignition circuit starts the ignition operation.

When the gas burner ignites and the safety circuit detects combustion flame, the safety circuit continues to energize the solenoid valve, the solenoid valve maintains the open state, and the gas burner continues combustion.
When an abnormality occurs, the safety circuit stops energizing the solenoid valve and closes the solenoid valve. Even if one of the safety circuits fails and a signal to stop energizing the solenoid valve is not output, the other safety circuit can stop energizing the solenoid valve.

[Claim 2] When the water flows through the heat exchange channel, the contact point of the water flow switch is closed. As a result, the switch element is turned on, and the valve body opens. At the same time, the ignition circuit starts the ignition operation.

When the gas burner ignites and the ignition detection element outputs a flame detection signal, each of the discriminators of the ignition detection circuit detects ignition, and the signal transmitter outputs an ON signal to the switch element. Is continuously energized, the solenoid valve remains open, and the gas burner continues combustion.

Further, when each discriminating section of the ignition detecting circuit detects a misfire, the OFF signal of the signal transmitting section is outputted to the switch element, so that the energization of the solenoid valve is stopped and the solenoid valve is closed.

Even when one of the discriminating units of the ignition detecting circuit fails (i.e., ignition is detected even though no flame detection signal is input), the normal discriminating unit and the signal transmitting unit cause the switch element to turn off the OFF signal. Can be sent to stop the energization of the solenoid valve.

[Claim 3] When water flows through the heat exchange channel, the contact point of the water flow switch is closed. As a result, the suction timer circuit sends an ON signal for a predetermined time and the first switch element is turned ON, so that the valve body opens. The ignition circuit also performs an ignition operation.

When the gas burner ignites and the ignition detection element outputs a flame detection signal, the first and second ignition detection circuits output an ON signal to the second and third switch elements, so that the holding coil is continuously energized. The solenoid valve remains open, and the gas burner continues combustion.

Even if one of the second switch element and the third switch element fails to turn on, if the first and second ignition detection circuits are normal, the normal switch element is turned off at the time of non-ignition or misfire. I can do things. Also, the first ignition detection circuit or the second ignition detection circuit
Even if one of the ignition detection circuits fails (a state in which the ignition detection element outputs an ON signal even though it does not output a flame detection signal), if the second and third switching elements are normal, at the time of non-ignition or misfire , Either the second switch element or the third switch element can be turned off.

[0016]

【The invention's effect】

[Claim 1] Even if one of the safety circuits fails, the other safety circuit can control the opening and closing of the solenoid valve.
Therefore, the solenoid valve can be reliably closed by the fire extinguishing instruction (the fire cannot be extinguished). In addition, the solenoid valve can be reliably closed in the event of misfire or misfire (no release of raw gas), which is excellent in safety.

[Claim 2] When one of the discriminating units of the ignition detecting circuit fails (it is detected that the ignition occurs even though no flame detection signal is inputted), the other discriminating unit and the signal transmitting unit which are normal, It is possible to control the transmission of the ON signal output to the switch element. For this reason, the solenoid valve can be reliably closed by stopping the flow of water flowing through the heat exchange channel (without extinguishing the fire). In addition, the solenoid valve can be reliably closed in the event of misfire or misfire (no release of raw gas), which is excellent in safety.

[Claim 3] When one of the second switch element and the third switch element has an ON failure, or
Even if one of the first ignition detection circuit and the second ignition detection circuit fails (a state in which the ignition detection element outputs an ON signal even though it does not output a flame detection signal), it is held by the normal switch element and the ignition detection circuit. It is possible to reliably control the holding current flowing through the coil. For this reason, the solenoid valve can be reliably closed by stopping the flow of water flowing through the heat exchange channel (without extinguishing the fire). In addition, the solenoid valve can be reliably closed in the event of misfire or misfire (no release of raw gas), which is excellent in safety.

[0019]

EXAMPLE A first example of the present invention (corresponding to claims 1 and 3)
Will be described with reference to FIGS. As shown in the figure, the gas instantaneous water heater A has a suction coil 11 and a holding coil 12, and an electromagnetic safety valve 1 disposed in a gas pipe 21 for supplying gas to the gas burner 2 and a transistor 13, 14,
15, a heat exchange channel 3 having a heat exchanger 31, a water flow switch 4 that closes a contact 41 when a water flow is detected, and a contact 4
When 1 is closed, ON signal 51 for a predetermined time (5.5 seconds)
1, a igniter timer circuit 51 and an igniter drive circuit 52 that generate a high voltage, a suction timer circuit 6 that sends an ON signal 61 for a first timer time (0.4 seconds) when the contact 41 is closed, When the contact 41 is closed, the second
When the holding timer circuit 7 that sends the ON signal 71 for the timer time (5.5 seconds) and the contact 41 are closed, detection of the combustion flame is started, and the transistor 1 is activated while the combustion flame is detected.
4 and 15, ignition detection circuits 81 and 82 for sending ON signals 811, 821.

Reference numeral 91 denotes a regulator. When the contact 41 is closed, a voltage V _CC2 (3V) is applied to the “IN” terminal 910, and a stabilized voltage V _CC is applied to the “OUT” terminal 911.
_REG (1.5V) is generated. Reference numeral 92 denotes a dry battery. In this embodiment, two single type 1.5V manganese dry batteries are connected in series to generate an electromotive force of voltage V _CC1 (3V). Reference numeral 9 denotes an electronic unit incorporating each circuit.

The electromagnetic safety valve 1 has a suction coil 11 (3.7 Ω) whose valve body opens when energized, and a holding coil 12 (500 Ω) which maintains the valve open state even after suction by energization. It is arranged at the uppermost stream of the pipe 21.

The gas burner 2 is installed below the heat exchanger 31, and gas is supplied by the gas pipe 21 to burn.
The gas pipe 21 is provided with an electromagnetic safety valve 1, a gas governor valve 211, a hydraulic automatic gas valve 212 connected to the water governor valve, and a capacity adjuster 213 from the upstream side.

In the combustion cylinder near the heat exchanger 31, 152
A thermal fuse 42 that melts at a temperature of not less than ° C is provided.
The thermal fuse 42 has one end electrically connected to the water flow switch 4 and the other end electrically connected to the “IN” terminal 910.

The automatic water pressure gas valve 212 is connected to the water governor 323 by the interlocking rod 43 and opens when water flows into the heat exchange channel 3. The ability adjuster 213 is an ability adjusting knob 2
A gas corresponding to the amount of sliding of the capacity adjusting knob 214 is connected to the gas passage 14.

The heat exchange channel 3 includes the water supply pipe 32 and the heat exchanger 3.
1 and a hot water outlet pipe 33 are connected in order. Water pipe 32
Is provided with a hot water supply plug (not shown), a water filter 321, a water governor 323, and a hot water amount adjuster 325 connected to the hot water temperature adjusting knob 324. The water flow switch 4 is inserted between the dry battery 92 and the temperature fuse 42, and is connected to the water governor 323.
Is connected to an interlocking rod 43 that connects the hydraulic pressure automatic gas valve 212 with each other, and the contact 41 is closed when a water flow flows.

The igniter timer circuit 51 sends an ON signal 511 to the igniter drive circuit 52 and the transistor 15 for 5.5 seconds after the start of power supply by closing the contact 41. The igniter drive circuit 52 generates a high voltage for spark discharge while the ON signal 511 is input, and applies the high voltage for ignition to the ignition electrode 521 arranged facing the gas burner 2. Since the current consumption is relatively large, the voltage V
_CC1 is used as operating power.

The ignition detection circuits 81 and 82 are, as shown in FIG. 7, a frame rod 8 arranged facing the gas burner 2.
00 is a circuit for detecting the flame current by applying an AC voltage (about 100 V) for flame current detection to the frame rod 80.
When 0 detects a flame current and outputs a flame detection signal 801 (detects ignition), ON signals 811, 821 are sent to the transistors 14, 15. The voltage V _CC2 is used as the operating power.

The suction timer circuit 6 includes a comparator and a CR.
When the stabilizing voltage V _REG is supplied as a timer operation start signal for stabilizing the timer time, the charging circuit is configured as a first timer time (0.4 seconds) and an ON signal 6
1 is sent to the transistor 13. Transistor 13
Is disposed between the suction coil 11 and the dry cell 92, and conducts while the ON signal 61 is being input.
Apply a suction current to.

The hold timer circuit 7 includes a comparator and a CR.
When the stabilization voltage V _REG is supplied as a timer operation start signal, the ON signal 71 is sent to the transistor 14 for the second timer time (5.5 seconds).

The transistors 14 and 15 are the holding coil 1
2− is connected in series between “OUT” terminals 911, and has an ON signal 811 (or ON signal 71) and an ON signal 821.
While (or ON signal 511) is input, the electromagnetic safety valve 1 is kept open by conducting the holding current through the holding coil 12 by conducting.

Next, the operation of the gas instantaneous water heater A will be described with reference to the flowcharts of FIGS. 4 and 5 and the time chart of FIG. [Usage of appliance (see FIG. 4)] When the user opens the hot water tap (step s1), the water flow switch 4 is closed (step s2), and the voltage V _CC2 is supplied to the “IN” terminal 910 of the regulator 91. As a result, the stabilization voltage V _REG is generated at the “OUT” terminal 911.

When the power supply of the regulated voltage V _REG is started, the following operation is performed in step s3. The igniter timer circuit 51 sends the ON signal 511 to the igniter drive circuit 52 and the transistor 15, and the igniter drive circuit 52.
Applies a high voltage to the ignition electrode 521 to start spark discharge. The suction timer circuit 6 sends an ON signal 61 to the transistor 13, and the transistor 13 is turned on to supply a suction current to the suction coil 11, so that the electromagnetic safety valve 1 is opened.
The holding timer circuit 7 outputs the ON signal 71 to the transistor 14
The transistor 14 is turned on (the transistor 15 is also turned on), and a holding current flows through the holding coil 12.

In step s4, the automatic hydraulic gas valve 212 is opened and the gas burner 2 is ignited. 0.4 seconds elapse from the start of closing the water flow switch 4 (YES in step s5).
And the suction timer circuit 6 sends the ON signal 61 to the transistor 1
3, the transistor 13 is turned off and the suction current does not flow in the suction coil 11 (step s
6).

When 5.5 seconds have passed from the start of closing the water flow switch 4 (YES in step s7), the holding timer circuit 7
Does not send the ON signal 71 to the transistor 14,
The igniter timer circuit 51 stops sending the ON signal 511 to the igniter drive circuit 52 and the transistor 15, and the spark discharge is stopped (step s8).

In the case of "normal", the ignition detection circuits 81 and 8
Since 2 has already detected the flame current and has sent the ON signals 811, 821 to the transistors 14, 15 (YES in step s9), the electromagnetic safety valve 1 is maintained. Voltage V
_CC1 is 1.8V or higher (YE in step s10)
S) If the flame current is detected, the hot water supply is continued until the device is stopped.

When the flame current is not detected (non-ignition; (b) in FIG. 6), when the flame current is no longer detected (misfire; FIG. 6)
(C)} or when the voltage V _CC1 becomes less than 1.8 V (voltage drop; (d) in FIG. 6), the confirmation lamp 93 is continuously turned on and the ON signal 81 by the ignition detection circuits 81, 82.
The output of 1,821 to the transistors 14 and 15 is stopped (step s11). As a result, the electromagnetic safety valve 1 is closed.

When the user notices abnormally and closes the hot water supply valve (step s12), water stops flowing, so the automatic water pressure gas valve 212 is closed (step s13), the water flow switch 4 is turned off, and the confirmation lamp 93 is turned on. The light is turned off (step s14).

[Stopping Use of Appliance (See FIG. 5)] When the user closes the hot water supply valve to stop the use (step S1),
Since the water stops flowing, the automatic water pressure gas valve 212 is closed (step S2) and the gas burner 2 is extinguished (step S3).
Then, the water flow switch 4 is turned off (step S4), and the electromagnetic safety valve 1 is closed (step S5).

The gas instantaneous water heater A has the following advantages [a] to [c] due to the following construction and operation. Holding coil 12
-Transistors 14 and 15 are connected in series between the “OUT” terminals 911 of the regulator 91, and the frame rod 8
Ignition detection circuits 81 and 8 that output ON signals 811, 821 to the transistors 14 and 15 when 00 detects a combustion flame.
2 are provided.

When one of the transistors 14 and 15 has an ON failure, if the ignition detection circuits 81 and 82 are normal, the ON signals 811 and 8 are output at the time of non-ignition and misfire.
By stopping 21, the normal transistors 14 and 15 can be turned off. When one of the ignition detection circuits 81 and 82 has an ON failure (a state in which the flame rod 800 outputs ON signals 811 and 821 even though it does not detect combustion flame), if the transistors 14 and 15 are normal, no ignition occurs. Some transistors 14 and 15 can be turned off at the time of a fire or a misfire. As a result, the holding current of the holding coil 12 is cut off, the electromagnetic safety valve 1 is closed, and the gas burner 2 is extinguished.

[A] Should the transistor 1
One of 4 and 15 is turned on, or the ignition detection circuit 8
Even if one of the valves 1 and 82 fails to turn on, if the hot water tap is closed, the flow of water flowing to the heat exchange channel 3 is stopped, and the water flow switch 4 is turned off, the electromagnetic safety valve 1 can be closed reliably and the fire cannot be extinguished. Excellent in safety.

[A] Should the transistor 1 be used before ignition.
If one of Nos. 4 and 15 has an ON failure, or if one of the ignition detection circuits 81 and 82 has an ON failure, if a misfire occurs during ignition or a misfire occurs during hot water supply, the electromagnetic wave can be reliably generated. The safety valve 1 can be closed. Therefore, the release of raw gas does not occur and the safety is excellent.

[C] Transistor 1 should be used by any chance.
When one of Nos. 4 and 15 has an ON failure, or when one of the ignition detection circuits 81 and 82 has an ON failure, if a misfire occurs during hot water supply, the electromagnetic safety valve 1 can be reliably closed. Therefore, the release of raw gas does not occur and the safety is excellent.

Next, a second embodiment of the present invention (corresponding to claim 2) will be described with reference to FIGS. 1, 2, 4, 5, 6, and 8. The gas instantaneous water heater B differs from the gas instantaneous water heater A in the following points. One transistor 14 is connected between the “OUT” terminal 911 of the holding coil 12 − regulator 91. The transistor 14 is turned on during the input of the on signal 71 or the on signal 851.

When the ignition detection circuit 8 detects the combustion flame of the gas burner 2, it determines the ignition based on the flame detection signal 801 output by the frame rod 800.
And a signal sending unit 85 that outputs an ON signal 851 when both the determining units 83 and 84 detect ignition. The igniter timer circuit 51 sends an ON signal 511 to the igniter drive circuit 52 for 5.5 seconds when the operating power is supplied.

Next, the operation of the gas instantaneous water heater B will be described based on the flowcharts of FIGS. 4 and 5 and the time chart of FIG. [Usage of appliance (see FIG. 4)] When the user opens the hot water tap (step s1), the water flow switch 4 is closed (step s2), and the voltage V _CC2 is supplied to the “IN” terminal 910 of the regulator 91. As a result, the stabilization voltage V _REG is generated at the “OUT” terminal 911.

When the supply of the regulated voltage V _REG is started, the following operation is performed in step s3. The igniter timer circuit 51 sends an ON signal 511 to the igniter drive circuit 52, the igniter drive circuit 52 applies a high voltage to the ignition electrode 521, and spark discharge starts. The suction timer circuit 6 sends an ON signal 61 to the transistor 13, and the transistor 13 is turned on to supply a suction current to the suction coil 11, so that the electromagnetic safety valve 1 is opened. The holding timer circuit 7 is
The ON signal 71 is sent to the transistor 14, the transistor 14 becomes conductive, and the holding current flows through the holding coil 12.

In step s4, the hydraulic automatic gas valve 212 is opened and the gas burner 2 is ignited. 0.4 seconds elapse from the start of closing the water flow switch 4 (YES in step s5).
And the suction timer circuit 6 sends the ON signal 61 to the transistor 1
3, the transistor 13 is turned off and the suction current does not flow in the suction coil 11 (step s
6).

When 5.5 seconds have elapsed from the start of closing the water flow switch 4 (YES in step s7), the holding timer circuit 7
Does not send the ON signal 71 to the transistor 14,
The igniter timer circuit 51 does not send the ON signal 511 to the igniter drive circuit 52, and the spark discharge is stopped (step s8).

In the case of "normal", the ignition detection circuit 8 has already detected the flame current and has sent the ON signal 851 to the transistor 14 (YES in step s9), so that the electromagnetic safety valve 1 is maintained. If the voltage V _CC1 is 1.8 V or higher (YES in step s10) and the flame current is detected, hot water supply is continued until the device is stopped.

When the flame current is not detected (non-ignition; (b) of FIG. 6), when the flame current is no longer detected (misfire; FIG. 6)
(C)} or when the voltage V _CC1 becomes less than 1.8 V {voltage drop; (d) in FIG. 6}, the confirmation lamp 93 is continuously lit and the ignition detection circuit 8 turns on the transistor 851 of the ON signal 851. The transmission to 14 is stopped (step s11). As a result, the electromagnetic safety valve 1 is closed.

When the user notices an abnormality and closes the hot water supply valve (step s12), water stops flowing, so the automatic water pressure gas valve is closed (step s13), the water flow switch 4 is turned off, and the confirmation lamp 93 is turned off. (Step s14).

[Stopping Use of Equipment (See FIG. 5)] When the user closes the hot water supply valve to stop the use (step S1),
Since the water does not flow, the automatic hydraulic gas valve is closed (step S2), the gas burner 2 is extinguished (step S3), the water flow switch 4 is turned off (step S4), and the electromagnetic safety valve 1
Is closed (step S5).

The gas instantaneous water heater B has the following advantages [d] to [f] due to the following construction and operation. Ignition detection circuit 8
Is connected to the transistor 14 between the "OUT" terminal 911 of the holding coil 12-regulator 91, the discrimination units 83 and 84 for detecting ignition based on the input of the flame detection signal 801 output from the frame rod 800, and Discriminator 8
3 and 84 are configured by a signal transmission unit 85 that outputs an ON signal when ignition is detected.

Even if one of the discriminating sections 83 and 84 of the ignition detection circuit 8 has an ON signal failure (when ignition is detected even though the frame rod 800 does not output the flame detection signal 801, the transistor 14 is still operating normally. If so, the transistor 14 can be turned off when not ignited or when misfired. As a result, the holding current of the holding coil 12 is cut off, the electromagnetic safety valve 1 is closed, and the gas burner 2 is extinguished.

[E] Even if one of the discrimination units 83 and 84 of the ignition detection circuit 8 fails in the ON signal during use, if the transistor 14 is normal, the hot water tap is closed and the heat exchange channel 3 is closed.
If the water flow is stopped and the water flow switch 4 is turned off, the transistor 14 is turned off and the electromagnetic safety valve 1 can be closed without fail so that the fire cannot be extinguished, which is excellent in safety.

[E] Even if one of the discriminators 83 and 84 of the ignition detection circuit 8 fails in the ON signal before ignition, if the transistor 14 is normal, misfire occurs during ignition or during hot water supply. When a misfire occurs, the electromagnetic safety valve 1 can be surely closed. Therefore, the release of raw gas does not occur,
Excellent safety.

[F] If one of the discriminating units 83 and 84 of the ignition detection circuit 8 fails in the ON signal during use, if the misfire occurs during hot water supply, the electromagnetic safety valve 1 can be reliably closed. . Therefore, the release of raw gas does not occur and the safety is excellent.

In the above embodiment, the electromagnetic valve has the suction coil and the holding coil separately, but a single coil may be used for both suction and holding.
Further, in the above embodiment, the water heater is shown as the combustion device,
It may be applied to other combustion devices such as a fan heater. Further, in the above embodiment, the flame rod is shown as the ignition detection element, but it may be a thermocouple.

[Brief description of drawings]

FIG. 1 is an external view of a gas instantaneous water heater according to first and second embodiments of the present invention.

FIG. 2 is a configuration diagram of a gas instantaneous water heater according to first and second embodiments of the present invention.

FIG. 3 is an electrical connection diagram of the gas instantaneous water heater according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the gas instantaneous water heater according to the first and second embodiments of the present invention.

FIG. 5 is a flowchart showing the operation of the gas instantaneous water heater according to the first and second embodiments of the present invention.

FIG. 6 is a time chart showing the operation of the instant gas water heaters according to the first and second embodiments of the present invention.

FIG. 7 is an electric circuit diagram of an ignition detection circuit used in the gas instantaneous water heater according to the first embodiment of the present invention.

FIG. 8 is an electrical connection diagram of a gas instantaneous water heater according to a second embodiment of the present invention.

[Explanation of symbols]

 A, B Gas instantaneous water heater (combustion device) 1 Electromagnetic safety valve (solenoid valve) 2 Gas burner 3 Heat exchange channel 4 Water flow switch 6 Suction timer circuit (suction circuit) 7 Holding timer circuit (holding circuit) 8, 81, 82 Ignition Detection circuit (safety circuit) 11 Suction coil 12 Holding coil 13 Transistor (first switch element) 14 Transistor (second switch element) 15 Transistor (third switch element) 21 Gas pipe (gas supply path) 31 Heat exchanger (heat Exchange part) 41 contact 51 igniter timer circuit (ignition timer circuit) 52 igniter drive circuit (ignition circuit) 71 ON signal 83, 84 discrimination unit 85 signal transmission unit 92 dry battery 511 ON signal 800 flame rod (ignition detection element) 801 flame detection Signal 811, 821 ON signal

Claims (3)

[Claims] 1. A solenoid valve which is disposed in a gas supply path for supplying gas to a gas burner and whose valve body is opened by energization, an ignition circuit which starts an ignition operation by an ignition instruction, and a combustion flame of an ignition instruction. A combustion device comprising a safety circuit for energizing the solenoid valve while detection is started and combustion flame is detected, wherein the safety circuit is provided in two systems. 2. A solenoid valve which is disposed in a gas supply passage for supplying gas to the gas burner and whose valve body is opened by energization, a heat exchange passage having a heat exchange section heated by the gas burner, and one end side. To a battery, a water flow switch whose contacts are closed when a water flow flowing through the heat exchange channel is detected, a switch element electrically connected between the solenoid valve and the battery, and when the water flow switch is closed. An ignition circuit that starts an ignition operation, an ignition detection element that is arranged in the vicinity of the gas burner and that outputs a flame detection signal when a combustion flame is detected, and the switch while the ignition detection element outputs the flame detection signal. In a combustion device including an ignition detection circuit that outputs an ON signal to an element, the ignition detection circuit includes two independent determination units that detect ignition based on the input of the flame detection signal, and both determination units. Part combustion apparatus, characterized in that has a both signal transmission unit which outputs the ON signal when detecting the ignition. 3. A suction coil for opening a valve body by energization and a holding coil for maintaining a valve open state by energization after suction, which are arranged in a gas supply passage for supplying gas to a gas burner. A solenoid valve, a heat exchange channel having a heat exchange section heated by the gas burner, a water flow switch having one end connected to a battery, and a contact point being closed when a water flow flowing through the heat exchange channel is detected, and the suction A first electrically connected between the coil and the battery;
A switch element, second and third switch elements electrically connected in series between the holding coil and the other end of the water flow switch, and electrically connected to the other end of the water flow switch to supply operating power. Then, for a predetermined time, a suction timer circuit that outputs an ON signal to the first switch element, an ignition circuit that starts an ignition operation by an ignition instruction, and a flame detection that is arranged near the gas burner and detects a combustion flame An ignition detection element that outputs a signal, and a first that outputs an ON signal to the second and third switch elements while the ignition detection element is outputting the flame detection signal,
A combustion device including a second ignition detection circuit.