JPH0942664A - Combustion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion apparatus capable of being adapted by simple work in case of gas change. SOLUTION: In an instantaneous gas water heater (A) having a water flow switch 4 which turns on at detection of water flow, a solenoid safety valve 1 disposed in a gas supply line, a retention timer circuit 7 for applying retention current for a specified period of time (e.g. 5 seconds) and an ignition detecting circuit 8 for detecting ignition of a gas burner, when gas is changed, for example, from city gas to natural gas, a service man connects a resistor 73 to a resistor 72 in the retention circuit 7 in parallel to shorten the period of time of sending an ON signal 71 (e.g. from 5.5 to 3 seconds).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a combustion device.

[0002]

2. Description of the Related Art As a combustion apparatus, for example, in a gas water heater, an electromagnetic valve is provided in a gas supply passage to a gas burner. Further, as an ignition means of a gas burner, for example, an ignition device that generates a high voltage by being energized to generate a spark discharge is known. Then, the solenoid valve and the ignition device described above,
Each is connected to a DC power source (for example, a dry battery) via a switching element such as a transistor, and when an ON signal is input to the transistor, the solenoid valve and the ignition device are energized.

Specifically, when a water flow switch for detecting a water flow is closed, an ON signal is sent to each transistor for controlling energization of an electromagnetic valve and an ignition device for a predetermined time (for example, 5 seconds).
It sends during. When the gas burner is ignited, an ON signal is sent from the safety device, and energization of the solenoid valve is continued even after a lapse of a predetermined time.

By the way, even when the water flow switch is closed and the gas burner is ignited, the time until ignition (before the safety device sends an ON signal) varies depending on the type of gas. In the case of a large amount of gas (propane gas, natural gas), the safety device sends an ON signal relatively quickly, but in the case of a gas with a small heating value (city gas), the ON signal is delayed. Therefore, the predetermined time of the holding timer circuit is set (fixed) according to the type of gas used.

[0005]

Therefore, when the type of gas to be used changes due to moving or gas conversion work, it is necessary to replace the control board in addition to the replacement of the gas burner and the like. There is a problem that it takes time.

An object of the present invention is to provide a combustion device that can cope with a change in the type of gas used by a simple operation.

[0007]

In order to solve the above problems, the present invention employs the following configurations. (1) An electromagnetic valve that is disposed in a gas supply path that supplies gas to a gas burner, and whose valve body opens by energization, and a holding circuit that energizes the electromagnetic valve for a predetermined time after an ignition instruction,
In the combustion device including an ignition circuit that starts an ignition operation according to an ignition instruction, and a safety circuit that starts detection of a combustion flame according to an ignition instruction and energizes the solenoid valve while the combustion flame is detected, The predetermined time of the circuit can be set arbitrarily.

(2) A solenoid valve which is disposed 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 side is connected to a battery, and a water flow switch whose contacts are closed when a water flow flowing in the heat exchange channel is detected, and a switch element electrically connected between the solenoid valve and the other end of the water flow switch, When an ignition circuit that starts an ignition operation when the water flow switch is closed and is electrically connected to the other end of the water flow switch and is supplied with operating power, an ON signal is output to the switch element for the predetermined time. The holding timer circuit for outputting and the other end of the water flow switch are electrically connected to each other, and when the operating power is supplied, detection of the combustion flame is started. While the combustion flame is detected, an ON signal is sent to the switch element. Send out In a combustion apparatus comprising a safety circuit, the predetermined time of the holding timer circuit, and can be set arbitrarily.

(3) In the configuration of the above (2), the holding timer circuit electrically connects one input end of the comparator to the other end of the water flow switch through a voltage dividing resistor and the other input end. Is grounded through a time setting resistor and electrically connected to the other end of the water flow switch through an electrolytic capacitor, and increases or decreases the predetermined time by changing the resistance value of the time setting resistor. Do it.

(4) With the configuration of the above (3), the predetermined time is shortened by connecting a time shortening resistor to both ends of the time setting resistor.

[0011]

[Action]

[Claim 1] When the burner is instructed to be ignited, the holding circuit energizes the solenoid valve, so that the valve body opens. At the same time, the ignition circuit starts the ignition operation. Since the holding circuit energizes the solenoid valve for the predetermined time, the solenoid valve maintains the open state for at least the predetermined time. When the gas burner ignites and the safety circuit detects combustion flame during the specified time, the safety circuit continues to energize the solenoid valve even after the specified time elapses, the solenoid valve remains open, and the gas burner continues combustion. To do.

Ignition (until the safety circuit detects a combustion flame)
When changing to a gas (city gas) with a small amount of heat generation, which takes some time, the serviceman sets the predetermined time of the holding circuit long in order to prevent ignition mistakes. When changing to a gas (propane gas or natural gas) that ignites relatively quickly and has a large calorific value, the serviceman sets a short predetermined time in order to reduce the amount of raw gas emission that occurs during non-ignition.

[Claim 2] When water is flowed through the heat exchange channel, the contact point of the water flow switch is closed. As a result, the solenoid valve is energized and the valve body opens. At the same time, the ignition circuit starts the ignition operation. Further, since the hold timer circuit sends an ON signal and the switch element is turned ON, the solenoid valve maintains the open state for at least a predetermined time.

When the gas burner is ignited and the safety circuit detects the combustion flame during the predetermined time, the safety circuit starts sending an ON signal to the switch element, so that the solenoid valve remains open even after the predetermined time has elapsed. , The gas burner continues to burn.

When changing to a gas (city gas) with a small amount of heat generation, which takes some time to ignite, the serviceman sets a predetermined time of the holding timer circuit to be long in order to prevent ignition mistakes. When changing to a gas (propane gas or natural gas) that ignites relatively quickly and has a large calorific value, the serviceman sets a short predetermined time in order to reduce the amount of raw gas emission that occurs during non-ignition.

[Claim 3] When water flows in the heat exchange channel and the contact of the water flow switch is closed, the electrolytic capacitor is charged at a speed according to the resistance value of the time setting resistor, and the potential of the other input terminal is increased. Will rise. Then, until the potential of the other input terminal becomes higher than the potential of the one input terminal (the predetermined time ends), the comparator outputs the ON signal and the switch element is turned on.

When the gas burner ignites and the safety circuit detects combustion flame during a predetermined time, the safety circuit sends an ON signal to the switch element, and the open state of the solenoid valve is maintained even after the lapse of the predetermined time, and the gas burner burns. To continue.

Ignition (until the safety circuit detects a combustion flame)
When changing to a gas (city gas) with a small amount of heat generation, which takes a little time, the serviceman increases the resistance value of the time setting resistor to lengthen the second timer time. Also, when changing to a gas with a large calorific value that ignites relatively quickly (propane gas or natural gas), the serviceman should lower the resistance value of the time setting resistor to prevent the release of raw gas at the time of ignition failure. To shorten the predetermined time.

[Claim 4] If a time-reducing resistor is connected to both ends of the time-setting resistor, the combined resistance value is lowered, and the predetermined time is shortened.

[0020]

【The invention's effect】

[Claim 1] In order to keep the solenoid valve open, the forced holding time for forcibly energizing the solenoid valve can be set arbitrarily. Even if the type is changed, it is not necessary to replace the control board, and the service person can easily set the forced holding time according to the type of gas.

[Claim 2] In order to keep the solenoid valve open, the forced holding time of the holding timer circuit for forcibly sending the ON signal to the switch element for controlling the energization of the solenoid valve is arbitrarily set. Since it is possible, even if the type of gas used changes due to moving or gas conversion work, it is not necessary to replace the control board, and the service person can easily set the forced holding time according to the type of gas. I can do things.

[Claim 3] It is not necessary to replace the control board even if the type of gas used changes due to moving or gas conversion work, and the service person increases or decreases the resistance value of the time setting resistor. You can change the forced holding time according to the type of gas.

[Claim 4] When the gas is changed to a gas with a large calorific value due to moving or gas conversion work,
It is not necessary to replace the control board, and the service person can change the forced holding time to short by simply connecting the time shortening resistor to both ends of the time setting resistor.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention (corresponding to claims 1 to 4) 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, 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, an ignition circuit 5 that starts an ignition operation by starting power supply by closing the contact 41,
A suction timer circuit 6 that sends an ON signal 61 for 0.4 seconds from the start of power supply, a holding timer circuit 7 that sends an ON signal 70 for 5.5 seconds / 3 seconds (second timer time) from the start of power supply, and a voltage. When power supply to V _CC2 is started, combustion flame detection is started, and while the combustion flame is detected, the transistor 14 is activated.
And an ignition detection circuit 8 for sending an ON signal 81 to the.

Reference numeral 91 is a regulator, and when the contact 41 of the water flow switch 4 is closed, a voltage V is applied to the "IN" terminal 910.
_CC2 is applied and the regulated voltage V is applied to the "OUT" terminal 911.
_REG (1.5V) is generated. Reference numeral 92 denotes a dry battery as a power source. 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 (3.7Ω) whose valve body opens when energized, and a holding coil 12 (500Ω) which maintains the valve open state by energizing after suction. 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 a water governor 323, and a capacity adjuster 213 from the upstream side.

The automatic water pressure gas valve 212 is connected to the water governor 323 by the interlocking rod 42 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 inserted between the dry battery 92 and the regulator 91 is a water governor 323.
Is connected to the interlocking rod 42 that connects the hydraulic pressure automatic gas valve 212 and the water flow, and the contact 41 is closed.

The ignition circuit 5 is an igniter timer circuit 51.
And an igniter drive circuit 52 for applying a high voltage for ignition to the ignition electrode 521 arranged facing the gas burner 2.

The igniter timer circuit 51 sends an ON signal 511 to the igniter drive circuit 52 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 and applies it to the ignition electrode 521 while the ON signal 511 is input.
Since the current consumption is relatively large, the voltage V _CC1 is used as the operating power.

The ignition detection circuit 8 is a circuit for detecting the flame current by applying an AC voltage (about 100 V) for flame current detection to the frame rod 800 arranged facing the gas burner 2. Upon detection (detection of ignition), the ON signal 81 is sent to the transistor 14. The voltage V
_CC2 is used as operating power.

A gas having a large calorific value (propane gas,
In the case of (natural gas), gas with a small calorific value (city gas)
Ignite earlier than in the case of.

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, the ON signal 61 is sent to the transistor 13 for 0.4 seconds. Transistor 1
3 is disposed between the suction coil 11 and the dry battery 92,
While the ON signal 61 is being input, it conducts and draws a suction current through the suction coil 11.

As shown in FIG. 7, the holding timer circuit 7 includes a comparator 71, a resistor 72 (time setting resistor), and a resistor 7
3 (resistance for time reduction), resistance 74, resistances 75 and 76 (resistance for voltage division), electrolytic capacitor 77 and the like.
When the stabilized voltage V _REG is supplied as the timer operation start signal, the ON signal 70 is supplied to the transistor 14 for 5.5 seconds (without the resistor 73) or 3 seconds (with the resistor 73).
Is sent.

As shown in FIG. 8, at the time of factory shipment,
The resistor 73 is not mounted on the substrate 700 (for areas where natural gas is used), and the resistor symbol 73 is provided on the upper surface of the substrate 700.
1, a white frame 732, a "R1" display 733 are silk-printed, and a hole 734 is formed. For the city gas use area, the circuit board 700 is shipped with the resistor 73 mounted on the board 700.

The transistor 14 is a holding coil 12-
The holding coil 1 is provided between the “OUT” terminals 911 and is conductive while the ON signal 70 or the ON signal 81 is input.
A holding current is applied to 2 to maintain the electromagnetic safety valve 1 open.

Next, the operation of the gas instantaneous water heater A will be described based on the flowcharts of FIGS. 4 and 5 and the time chart of FIG. 6 (when the resistor 73 is not used). [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 70 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 (at normal time). 0.4 seconds elapses from the start of closing the water flow switch 4 (step s5
If YES), the suction timer circuit 6 does not send the ON signal 61 to the transistor 13, the transistor 13 is turned off, and the suction current does not flow in the suction coil 11 (step s6).

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 70 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 81 to the transistor 14 (YES in step s9).
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 (misfire; (d) in FIG. 6), the confirmation lamp 93 is continuously lit and the transistor 14 of the ON signal 81 by the ignition detection circuit 8 is turned on. Is stopped (step s11). As a result, the electromagnetic safety valve 1 is closed.

When the user notices abnormally and closes the hot water tap (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 the use of equipment (see FIG. 5)] When the user closes the hot water tap 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 advantages of the instant gas water heater A of this embodiment will be described below. [A] When the gas to be used is changed from a gas with a small calorific value (city gas) to a gas with a large calorific value (propane gas, natural gas) due to gas conversion work or moving, the service person is a part of the gas burner 2, etc. Replace hole 734
It suffices to insert a lead wire into and to solder the resistor 73 from the back surface of the substrate 700. Further, when the user moves to an area where a gas (city gas) having a small amount of heat generation is used, the resistor 73 (performed by a service person) may be removed.
These operations are performed by the resistance symbol 731, the white frame 732
Also, since the "R1" display 733 makes it easy to understand, the service person can surely perform in a short time.

[A] The gas instantaneous water heater A for shipping to a region where a gas having a small calorific value (city gas) is used has a substrate 7
If the production control is done so that the resistor 73 is attached to 00 and the gas having a large calorific value (propane gas, natural gas) is not attached to the region, the substrate 700 can be standardized, and the manufacturer can reduce the administration cost. It can be reduced.

[C] Since the second timer for supplying the holding current to the holding coil 12 of the electromagnetic safety valve 1 can be set to a length (5.5 seconds / 3 seconds) suitable for the type of gas, a gas with a small heating value can be used. Ignition mistakes during use can be prevented, and the release of raw gas (which occurs during non-ignition) when using a gas with a large amount of heat generation can be reduced.

The present invention includes the following embodiments in addition to the above embodiments. a. The combustion device according to claim 1 may be a gas table, a bath kettle, or the like. The power source may be other than the battery. In addition, I have shown that the setting of the time is switched by detaching the resistor,
You may make it switch by attaching or detaching a capacitor.
Alternatively, the switching may be performed according to the resistance value of the variable resistor.

B. In the combustion apparatus according to claim 2, the resistance value of the time setting resistor is increased / decreased by operating a variable resistor, a DIP switch connecting resistors having different resistance values, disconnecting the resistor,
It can be done by exchanging resistors or cutting jumper wires that jumper a specific resistor. c. The second timer time may be set in multiple stages or infinitely. d. In the solenoid valve, one coil may serve both as suction and holding.

[Brief description of 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 the gas instantaneous water heater.

FIG. 3 is a block diagram of the gas instantaneous water heater.

FIG. 4 is a flowchart showing the operation of the gas instantaneous water heater.

FIG. 5 is a flowchart showing the operation of the gas instantaneous water heater.

FIG. 6 is a time chart showing the operation of the gas instantaneous water heater.

FIG. 7 is an electric circuit diagram of a holding timer circuit used in the gas instantaneous water heater.

FIG. 8 is an explanatory diagram showing a state of the upper surface of the substrate.

[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 5 Ignition circuit 7 Holding timer circuit 8 Ignition detection circuit (safety circuit) 14 Transistor (switch element) 21 Gas pipe (Gas supply path) 31 Heat exchanger (heat exchange section) 41 Contact point 71 Comparator (comparator) 72 Resistance (time setting resistance) 73 Resistance (time shortening resistance) 75, 76 Resistance (voltage dividing resistance) 77 Electrolytic capacitor 92 Batteries

Claims (4)

[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, and a holding circuit which energizes the solenoid valve for a predetermined time from an ignition instruction. A combustion circuit comprising: an ignition circuit that starts an ignition operation according to an ignition instruction; and a safety circuit that starts detection of a combustion flame according to an ignition instruction and energizes the solenoid valve while the combustion flame is detected, A combustion device characterized in that the predetermined time of the holding circuit can be arbitrarily set. 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 detecting a water flow flowing in the heat exchange channel, and a switch element electrically connected between the solenoid valve and the other end of the water flow switch, An ignition circuit that starts an ignition operation when the water flow switch is closed, and is electrically connected to the other end of the water flow switch, and when operating power is supplied, outputs an ON signal to the switch element for the predetermined time. A holding timer circuit that is electrically connected to the other end of the water flow switch, starts detecting combustion flame when operating power is supplied, and outputs an ON signal to the switch element while combustion flame is detected. Send out A combustion device comprising a safety circuit, wherein the predetermined time of the holding timer circuit can be arbitrarily set. 3. The holding timer circuit electrically connects one input end of a comparator to the other end of the water flow switch via a voltage dividing resistor and grounds the other input end via a time setting resistor. The combustion device according to claim 2, wherein the combustion device is configured to be electrically connected to the other end side of the water flow switch via an electrolytic capacitor, and the predetermined time is increased or decreased by changing the resistance value of the time setting resistor. 4. The combustion apparatus according to claim 3, wherein the predetermined time is shortened by connecting time shortening resistors to both ends of the time setting resistor.