JP3087885B2 - Combustion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a combustion apparatus.

[0002]

2. Description of the Related Art Conventionally, an electromagnetic valve provided in a gas supply path for supplying gas to a gas burner and a water flow switch are closed to give an ignition instruction or the like for a predetermined time (for example, 0.
(4 seconds), a suction holding circuit for energizing the solenoid valve, an ignition circuit for applying a high voltage to the ignition electrode according to an ignition instruction, a flame rod facing the gas burner, and detecting ignition based on the output of the flame rod. There is known a combustion device including an ignition detection circuit that sends an ON signal to a transistor electrically connected between an electromagnetic valve and a battery during detection.

[0003]

In the above combustion apparatus, safety in the event of misfiring or misfiring is maintained by the transistor and the ignition detecting circuit. In the unlikely event that the ignition detection circuit fails, an ON signal is sent to the transistor irrespective of the presence or absence of ignition, and even if the ignition detection circuit is normal, if the transistor turns on, current will flow through the solenoid valve regardless of the presence of ignition. Flows. An object of the present invention is to provide a combustion device with improved safety.

[0004]

In order to solve the above-mentioned problems, a combustion apparatus according to the present invention comprises a suction coil in which a valve element opens by energization, and a holding coil for maintaining a valve open state by energization after suction. A solenoid valve disposed in a gas supply path for supplying gas to a gas burner, a heat exchange water path having a heat exchange section heated by the gas burner, and one end connected to a battery, A water flow switch whose contact is closed when a water flow flowing in the water channel is detected, a first switch element electrically connected between the suction coil and the battery, and a water flow switch between the holding coil and the other end of the water flow switch. Second and third switch elements electrically connected in series to the other end of the water flow switch, and output an ON signal to the first switch element for a predetermined time when power for operation is supplied. With a suction timer circuit An ignition circuit for starting an ignition operation according to an ignition instruction, an ignition detection element arranged near the gas burner and outputting a flame detection signal when detecting a combustion flame, and while the ignition detection element is outputting the flame detection signal. , A first and a second for outputting an ON signal to the second and third switch elements.
A configuration including an ignition detection circuit is employed.

[0005]

[0006]

[0007]

When the water flows through the heat exchange channel, the contact 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 performs an ignition operation. When the gas burner is ignited and the ignition detection element outputs a flame detection signal, the first and second ignition detection circuits output ON signals to the second and third switch elements, so that the holding coil is continuously energized, and the solenoid valve is turned on. Keeps the valve open, and the gas burner continues burning. Even if one of the second switch element and the third switch element fails, if the first and second ignition detection circuits are normal, the normal switch element can be turned off at the time of non-ignition or misfire. . Also, even if one of the first ignition detection circuit and the second ignition detection circuit fails (a state where the ignition detection element outputs an ON signal while the flame detection signal does not output), the second and third switch elements are normal. Then, at the time of non-firing or misfiring, either the second switch element or the third switch element can be turned off.

[0008]

[0009]

[0010]

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

When one of the second switch element and the third switch element fails to turn on, or one of the first ignition detection circuit and the second ignition detection circuit fails (the ignition detection element does not output a flame detection signal). Even when the ON signal is output), the holding current flowing through the holding coil can be reliably controlled by the normal switch element and the ignition detection circuit. Therefore, if the water flow to the heat exchange water channel is stopped, the solenoid valve can be reliably closed (the fire cannot be extinguished). In addition, the solenoid valve can be reliably closed in the event of misfiring or misfiring (there is no emission of raw gas), resulting in excellent safety.

[0017]

[0018]

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. As shown in the figure, a gas instantaneous water heater A has a suction coil 11 and a holding coil 12, and is provided with an electromagnetic safety valve 1 disposed in a gas pipe 21 for supplying gas to a gas burner 2.
A heat exchange channel 3 having transistors 13, 14, 15 and a heat exchanger 31, a water flow switch 4 for closing a contact 41 when a water flow is detected, and a predetermined time (5.5 seconds) when the contact 41 is closed. ), An igniter timer circuit 51 and an igniter drive circuit 52 for transmitting an ON signal 511 and generating a high voltage, and a suction timer for transmitting an ON signal 61 for a first timer time (0.4 seconds) when the contact 41 is closed. When the circuit 6 and the contact 41 are closed, the second timer time (5.5)
Second), a holding timer circuit 7 for sending an ON signal 71,
When the contact 41 is closed, detection of a combustion flame is started, and ignition detection circuits 81 and 82 are provided for sending on signals 811 and 821 to the transistors 14 and 15 while the combustion flame is detected.

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

The electromagnetic safety valve 1 has a suction coil 11 (3.7Ω) whose valve body opens when energized, and a holding coil 12 (500Ω) for maintaining 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 is supplied with gas by the gas pipe 21 and burns.
The gas pipe 21 is provided with an electromagnetic safety valve 1, a gas governor valve 211, a water pressure automatic gas valve 212 connected to a water governor valve, and a capacity adjuster 213 from the upstream side.

The combustion cylinder near the heat exchanger 31 has 152
A thermal fuse 42 that melts at a temperature equal to or higher than ° C. is provided.
One end of the thermal fuse 42 is electrically connected to the water flow switch 4, and the other end is electrically connected to the “IN” terminal 910.

The hydraulic automatic gas valve 212 is connected to the water governor 323 by the interlocking rod 43 and opens when water flows into the heat exchange water passage 3. The ability adjuster 213 is provided with the ability adjust knob 2.
14 and passes an amount of gas corresponding to the sliding amount of the capacity adjustment knob 214.

The heat exchange channel 3 includes a water supply pipe 32, a heat exchanger 3
1. The tapping pipe 33 is sequentially connected. Water supply pipe 32
Is provided with a hot water tap (not shown), a water filter 321, a water governor 323, and a hot water volume controller 325 connected to a hot water temperature control knob 324. The water flow switch 4 is inserted between the dry cell 92 and the thermal fuse 42, and is connected to the water governor 323.
And an interlocking rod 43 connecting the automatic water pressure gas valve 212 and the contact point 41 is closed when the water 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 from 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 being input, and applies the high voltage for ignition to the ignition electrode 521 disposed facing the gas burner 2. Since the current consumption is relatively large, the voltage V
_CC1 is used as the operating power.

As shown in FIG. 7, the ignition detection circuits 81 and 82 are provided with a frame rod 8 disposed facing the gas burner 2.
This circuit detects 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), it sends ON signals 811 and 821 to the transistors 14 and 15. The voltage V _CC2 is used as the operating power.

The suction timer circuit 6 includes a comparator, CR
When a stabilizing voltage V _REG is supplied as a timer operation start signal for stabilizing the timer time, a stabilizing voltage V _REG is supplied to the first timer time (0.4 seconds).
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 input.
A suction current

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

The transistors 14 and 15 are connected to the holding coil 1
2-An ON signal 811 (or ON signal 71) and an ON signal 821
(Or the ON signal 511) is input, the conduction is made, and a holding current is supplied to the holding coil 12 to keep the electromagnetic safety valve 1 open.

Next, the operation of the instantaneous gas heater A will be described with reference to the flowcharts of FIGS. 4 and 5 and the time chart of FIG. [Start of use of the 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. Then, a stabilized voltage V _REG is generated at the “OUT” terminal 911.

When the supply of the stabilized 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 and the transistor 15, and 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 outputs the ON signal 71 to the transistor 14
And the transistor 14 is turned on (the transistor 15 is also turned on), and a holding current flows through the holding coil 12.

At step s4, the automatic hydraulic gas valve 212 is opened, and the gas burner 2 is ignited. 0.4 seconds have passed since the closing of the water flow switch 4 was started (YES in step s5).
And the suction timer circuit 6 outputs the ON signal 61 to the transistor 1
3, the transistor 13 is turned off, and the attraction current does not flow through the attraction coil 11 (step s).
6).

When 5.5 seconds have passed since the closing of the water flow switch 4 (YES in step s7), the holding timer circuit 7
Stops sending 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 transistor 15, and the spark discharge stops (step s8).

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

When no flame current is detected {no ignition; FIG. 6 (b)}, when no flame current is detected {misfire; FIG.
(C)} or when the voltage V _CC1 becomes less than 1.8 V {voltage drop; (d)} in FIG. 6 shows that the confirmation lamp 93 is continuously turned on and the ON signal 81 by the ignition detection circuits 81 and 82
The transmission of 1,821 to the transistors 14, 15 stops (step s11). As a result, the electromagnetic safety valve 1 closes.

When the user notices an abnormality and closes the hot water supply valve (step s12), the 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).

[Suspension of use of appliance (see FIG. 5)] To stop use, the user closes the hot water supply valve (step S1).
Since water stops flowing, the automatic hydraulic 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 instantaneous gas water heater A has the following advantages [A] to [C] by the following configuration and operation. Holding coil 12
-Connect the transistors 14 and 15 in series between the "OUT" terminal 911 of the regulator 91 and connect the frame rod 8
When 00 detects a combustion flame, the ignition detection circuits 81 and 8 output on signals 811 and 821 to the transistors 14 and 15, respectively.
2 are provided.

When one of the transistors 14 and 15 is turned on and the ignition detection circuits 81 and 82 are normal, the ON signals 811 and 811 are output when the ignition is not performed or the misfire occurs.
By stopping the operation of the transistor 21, the normal transistor 14, 15 can be turned off. If one of the ignition detection circuits 81 and 82 has an ON failure (a state in which the flame rod 800 outputs the ON signals 811 and 821 without detecting the combustion flame), if the transistors 14 and 15 are normal, the ignition is not performed. Some of the transistors 14, 15 can be turned off at the time of a fire or misfire. As a result, the holding current of the holding coil 12 is cut off, the electromagnetic safety valve 1 closes, and the gas burner 2 extinguishes.

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

[A] Before the ignition, the transistor 1
If one of the ignition failures 4 and 15 has an ON failure or one of the ignition detection circuits 81 and 82 has an ON failure, the occurrence of misfiring at the time of ignition or misfire during hot water supply surely causes electromagnetic interference. The safety valve 1 can be closed. Therefore, the release of raw gas does not occur, and the safety is excellent.

[C] Should the transistor 1 be used
If one of the ignition failures 4 and 15 is turned on or one of the ignition detection circuits 81 and 82 is turned on and 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.

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

In the above embodiment, the solenoid valve has a suction coil and a holding coil separately. However, a single coil may be used for both suction and holding.
In the above embodiment, the water heater is shown as the combustion device.
You may apply to another combustion apparatus, such as a fan heater. Further, in the above embodiment, the flame rod is shown as the ignition detection element, but a thermocouple may be used.

[Brief description of the drawings]

FIG. 1 is an external view of a gas instantaneous water heater according to one embodiment of the present invention.

FIG. 2 is a configuration diagram of a gas instantaneous water heater according to one embodiment of the present invention.

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

FIG. 4 is a flowchart illustrating an operation of a gas instantaneous water heater according to one embodiment of the present invention.

FIG. 5 is a flowchart showing an operation of the instantaneous gas water heater according to one embodiment of the present invention.

FIG. 6 is a time chart showing the operation of the instantaneous gas water heater according to one embodiment of the present invention.

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

[Explanation of symbols]

 A 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 unit) ) 41 contacts 51 igniter timer circuit (ignition timer circuit) 52 igniter drive circuit (ignition circuit) 71 ON signal 83, 84 discriminating unit 85 signal sending unit 92 dry cell 511 ON signal 800 flame rod (ignition detecting element) 801 flame detection signal 811 , 821 ON signal

Claims (1)

(57) [Claims] 1. A gas supply path for supplying gas to a gas burner, comprising: a suction coil for opening a valve body by energization; and a holding coil for maintaining a valve open state by energization after suction. A water flow switch having a heat exchange section heated by the gas burner; a water flow switch having one end connected to a battery and closing a contact when a water flow flowing through the heat water flow path is detected; A first electrical connection 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 according to an ignition instruction, and a flame detection that is disposed 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 outputs the flame detection signal.
A combustion device comprising: a second ignition detection circuit.