JPS63176921A - Controller for combustion apparatus - Google Patents

Abstract

PURPOSE:To obtain highly accurate cooking performance and permit combustion in the title apparatus to be stopped upon an accident such as earthquake or the like, by a method wherein the titled controller is provided with a vibration sensitive switch, a safety valve for supplying fuel and a temperature sensor provided so as to be capable of insertion into a pot or the like. CONSTITUTION:A controller is constituted of a vibration sensitive switch 55, an oscillating circuit 3, which becomes the criterion for the title controller, an ignition timer circuit 8, a flame detecting circuit 14, a first reference voltage generating circuit 29, a second reference voltage generating circuit 33, a temperature sensor 38, inserted directly into a food to be heated in a pot, a first comparator 39, a second comparator 41, a NOR circuit 43, a NAND circuit 44, a DC-DC converter circuit 45 and a safely valve 54. The temperature sensor 38 is inserted directly into the food to be heated in the pot in such a manner, therefore, highly accurate cooking performance may be provided. Further, the supply of power source for a control circuit is stopped and the safety valve 54 is closed to stop the supply of fuel as well as the combustion of the title combustion apparatus when a gas range is vibrated in some degree of vibration or more by earthquake or the like to open the vibration sensitive switch 55.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a combustor such as a piezoelectric ignition type gas stove.

BACKGROUND OF THE INVENTION FIG. 2 shows a conventional control device for a piezoelectric ignition type gas stove. In Fig. 2, 1 is a DC power supply, 2 is an operation switch that is linked to the cock that opens and closes the fuel supply path of the piezoelectric ignition type gas stove, 3 is an oscillation circuit that is the reference of this control device, 8 is an ignition timer circuit, and 14 is a flame Detection circuit, 29 is the first reference voltage generation circuit, 33 is the second unit! $Voltage generation circuit, 3
8 is a temperature sensor that detects the temperature of the bottom of the pot heated by the burner; 39 is a first converter; 411d is a second converter; 43 is a NOR circuit; 44 is a NAND circuit; 45 is a D
The C-DC converter circuit 54 is a safety valve that opens and closes the fuel supply path.

When the cock of the piezoelectric ignition type gas stove is opened (hereinafter referred to as ON), power is supplied from the DC power supply 1 by the operation switch 2 linked thereto, and the oscillation circuit 3, which is the reference of this control device, oscillates and produces a pulse output. The oscillation circuit 3 includes an inverter 4.7, a resistor 5, and a capacitor 6. Next, when the operation switch 2 is turned on, the capacitor 11.12 is charged through the resistor 9.10, and the charged voltage V is set by the OR circuit 13 which receives this charging voltage V and the output of the oscillation circuit 3. 13 threshold voltage VI
The output of the ignition timer circuit 8 becomes a pulse in phase with the output of the oscillation circuit 3 during the charging time to H, and this state is between time t1 and time t2 in FIG. 3. Thermocouple 18 which is a flame sensor
When no electromotive force is generated, the output of the flame detection circuit 14 becomes the output voltage (=VDD) of the DC power supply 1, and the transistors 30 and 34 are in an OFF state. At this time, the outputs of the first reference voltage generation circuit 29 and the second t$ voltage generation circuit 33 are R31-R35, R32=
Since it is designed as R36, it is input to the ten input terminals of the first comparator 39 and the second converter 41. Since no electromotive force is generated in the flame sensor 18, the resistance value of the temperature sensor 38 provided in contact with the bottom of the pot is sufficiently large.

The outputs of the first and second conhalators 39 and 41 are at a low potential (hereinafter referred to as vL) and are input to the NAND circuit 44 via the NOR circuit 43. Therefore, the output of the NAND circuit 44 is determined by the output of the ignition timer circuit 8, and while the output of the ignition timer circuit 8 is pulsed, it is not a pulse output, and is forcibly output by turning on the cock of the piezoelectric ignition type gas stove. The switching transistors 51 and 48 of the DC-DC converter circuit 45 for holding the safety valve 54 by suction are driven. As a result, a pulse voltage is generated on the secondary side of the Sibarst transformer 49, which is rectified by the semiconductor element 52, smoothed by the capacitor 53, and then applied to the safety valve 54.
voltage can be supplied to. Resistors 47 and 50 are current limiting resistors, and resistor 46 is a pace-emic resistor of transistor 48. If the output of the ignition timer circuit 8 does not generate an electromotive force in the thermocouple 18 during the pulse, that is, between time t1 and t2, the output of the ignition timer circuit 8 becomes a high potential (hereinafter referred to as VH) at time t3, The output of the NAND circuit 44 becomes VL because the output of the NOR circuit 43 is vH,
The DC-DC converter circuit 45 cannot be driven, no voltage is generated on the secondary side of the pulse transformer 490, and the safety valve 54 closes to cut off the gas that is the fuel.

Next, when an electromotive force is generated in the thermocouple 18 between time t1 and t2, the input voltage at one input terminal of the converter 22 constituting the flame detection circuit 14 is lowered to a low potential by the transistor 23 switched by the output of the oscillation circuit 3. is VL, and resistance 1
The voltage determined by 5.16.17.20 and the time constant of the capacitor 21 becomes a pulse with a high potential vH. When the electromotive force of the thermocouple 18 exceeds the voltage drop of the resistor 16, the output of the comparator 22 becomes a pulse output using the resistors 25, 26, 27, and 28 as load resistances. This is the output of the flame detection circuit 14 and is input to the second reference voltage generation circuit 29 and the second voltage generation circuit 33, and is supplied to the comparator 39 and the second comparator 41 input terminal. In normal combustion, the outputs of the first comparator 39 and the second comparator 41 are both pulsed and input to the NOR circuit 43 in the temperature sensor, and the output of the NOR circuit 43 is input to the NAND circuit 44. As a result, even if the output of the ignition timer circuit 8 is no longer a pulse, the output of the NOR circuit 43
The output of the AND circuit 44 can drive the pulse and 1) the DC-DC converter circuit 45, keep the safety valve 54 open, supply fuel, and continue combustion.

Next, when tempura oil or the like overheats abnormally, the voltage across the temperature sensor 38 drops below the low potential of the reference voltages of the first reference voltage generation circuit 29 and the second reference voltage generation circuit 330, causing the first comparator 39 and the second comparator Both outputs of 41 are no longer pulses. Therefore, DC-DC converter 45
will not operate and the safety valve will close, stopping combustion and preventing tempura fires.

Problems to be Solved by the Invention However, this configuration has a disadvantage in that the temperature detected by the temperature sensor 38 is the temperature at the bottom of the pot and is easily influenced by the shape and material of the pot. Furthermore, although there was a function to stop combustion in the event of abnormal heating of tempura oil, etc., there was no function to stop combustion in the event of a disaster such as an earthquake.

The present invention solves these conventional problems by inserting a multi-temperature sensor into an object to be heated, such as a pot, and provides highly accurate cooking performance.
In addition, the present invention provides an extremely safe combustor control device that can stop the combustion of the appliance through the action of a seismic switch in the event of a disaster such as an earthquake.

Means for Solving the Problems The control device of the present invention that solves the above problems includes a DC power supply,
An operation switch, a seismic switch, a safety valve for supplying fuel, an oscillation circuit that serves as a reference for the control device, a flame detection circuit that uses a thermocouple as a flame sensor and generates a chivalrous output by the electromotive force of the flame sensor; an ignition timer circuit for holding the safety valve until the thermal electromotive force of the flame sensor is sufficiently built up;
A temperature sensor that can be inserted into the inside of a pot or the like that is an object to be heated, a first reference voltage generation circuit generated by the output of the flame detection circuit, and the first reference voltage generated by the output of the flame detection circuit. a second reference voltage generation circuit that is a backup circuit of the generation circuit; a first converter that compares the output of the first reference voltage generation circuit with a voltage across the temperature sensor; and an output of the second reference voltage generation circuit. a second converter that compares voltages across the temperature sensor; a NOR circuit that receives the output of the first converter and the output of the second converter; and an output of the ignition timer circuit and the NOR circuit. It consists of a NAND circuit, and a DC-DC converter circuit that is driven by the output of the NAND circuit and uses the safety valve as a load.

Function: The control device of the present invention has a configuration in which the temperature sensor is inserted directly into the object to be heated in the pot, so it can provide highly accurate cooking performance, and the seismic switch functions to prevent earthquakes, etc. Even in the event of a natural disaster, it is possible to stop combustion and prevent disasters such as fire.

Embodiment Hereinafter, a gas stove control device according to an embodiment of the present invention will be described with reference to the drawings. Note that the same parts as in FIG. 2 are given the same reference numerals, detailed explanations are omitted, and different parts will be mainly explained. As shown in Fig. 1, 1 is a DC power supply, 2 is an operation switch that is linked to a cock that opens and closes the fuel supply path of the piezoelectric ignition type gas stove, 55 is a vibration sensing switch, and 3
8 is an ignition timer circuit, 14 is a flame detection circuit, 29 is a first reference voltage generation circuit,
33 is a second reference voltage generation circuit, 3B is a temperature sensor inserted directly into the object to be heated in the pot, 39 is a first converter,
41 is a second converter, 43 is a NOR circuit, and 44 is an N
An AND circuit, 45 a DC-DC converter circuit, and 54 a safety valve.

In the above embodiment, the ignition operation is the same as that shown in FIG. 2, but when the gas stove trembles at a certain seismic intensity or higher due to an earthquake or the like, the seismic switch 55 is opened and the power supply to the multi-control circuit is stopped, and the safety valve 54 The valve is closed, the fuel supply is stopped, and combustion is stopped. Effects of the Invention As described above, according to the combustor control device of the present invention, the temperature sensor is directly inserted into the object to be heated in the pot. The configuration is
It is extremely advantageous in practice, as it can provide highly accurate cooking performance, and can automatically stop combustion in the event of a natural disaster such as an earthquake due to the action of the seismic switch.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a gas stove control device employing an embodiment of the present invention, FIG. 2 is a conventional circuit diagram of the same device, and FIG. 3 is a time chart showing input and output waveforms of an ignition timer circuit.
4 (,) and (b) are input/output waveform diagrams of the comparator 22 of the flame detection circuit 14, and (C) and (d) are time charts showing the output waveforms of the first and second reference voltage generation circuits. The horizontal axis shows time and the vertical axis shows voltage. 1...DC power supply, 2...Operation switch, 3...Oscillation circuit, 8...Ignition timer circuit, 14...Flame detection Circuit, 29...
First reference voltage generation circuit, 33... Second reference voltage generation circuit, 38... Temperature sensor, 39...
...First converter, 41...Second converter, 43...NOR circuit, 44...
NAND circuit, 45...D C-DC converter circuit, 54... Safety valve, 55...
Seismic switch.

Claims (1)

[Claims] A DC power supply, an operating switch, a seismic switch, a safety valve for supplying fuel, an oscillation circuit that serves as the reference for the control device, and a flame detection circuit that uses a thermocouple as a flame sensor and outputs pulses due to the electromotive force of the flame sensor. , an ignition timer circuit for holding the safety valve until the thermal electromotive force of the flame sensor is sufficiently built up, a temperature sensor installed so as to be inserted into the inside of the object to be heated, such as a pot, and the flame sensor. a first reference voltage generation circuit generated by the output of the detection circuit; a second reference voltage generation circuit generated by the output of the flame detection circuit and serving as a backup circuit for the first reference voltage generation circuit; and the first reference voltage generation circuit. a first converter that compares the output of the second reference voltage generating circuit with the voltage across the temperature sensor, a second converter that compares the output of the second reference voltage generating circuit with the voltage across the temperature sensor, and the output of the first converter. a NOR circuit whose input is the output of the second converter; a NAND circuit whose inputs are the output of the ignition timer circuit and the output of the NOR circuit; and a DC circuit driven by the output of the NAND circuit and whose load is the safety valve. A combustor control device consisting of a DC converter circuit.