JPH0367921A - Burner controller - Google Patents

Abstract

PURPOSE:To make it possible to open a solenoid safety valve rapidly by passing an electric current which flows in the direction in which the electromotive force of a thermo-element is annulled in order to release a fire extinguishing operation. CONSTITUTION:A transistor 32 which is a switching element is installed and connected to a reverse electric current circuit 31 which passes electric current flowing in the direction in which it annulls the electromotive force of a thermocouple 12 and a condenser 33 is provided which is charged only during fire extinguishing operation. By charging said condenser 33 the transistor 32 is energized. By the way, in this case a pair of transistors 32 and a pair of capacitors 33 are provided to improve reliability. With this arrangement the capacitor 33 is charged by a battery 21, if a change-over switch 27 is returned to a terminal 27b on the upper side by fire-extinguishing operation, and during the charging the transistor 32 is energized, and the circuit 31 becomes a closed circuit and electric current flows in a coil 20b of the circuit 31 in the direction in which residual electromotive force is annulled, and solenoid safety valve is soon opened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control device for a water heater or other combustor, particularly for a combustor equipped with an electromagnetic safety valve.

(Prior Art) A conventional device of this kind includes an electromagnetic safety valve interposed in a fuel supply path to a burner, a timer circuit, and a thermoelectric element connected to a coil of the electromagnetic safety valve and heated by the burner. , the electromagnetic safety valve opened in conjunction with the ignition operation is maintained in an open state by the operation of the timer circuit for a certain period of time until a predetermined electromotive force is generated from the thermoelectric element, and when the predetermined electromotive force is generated; It is known that this electromotive force is used to keep the valve open to continue combustion in the burner.

(Problem to be Solved by the Invention) However, since the thermoelectric element generally has a residual electromotive force even after the fire extinguishing operation, the electromagnetic safety valve remains open for 20 to 30 seconds even after the extinguishing operation. There was an inconvenience that it was kept in the

Therefore, as shown in Fig. 4, a capacitor d is provided which is charged by the power supply C during a fire extinguishing operation when the changeover switch a is connected to the upper terminal, and the electromotive force of the thermoelectric element e is canceled by charging the capacitor d. It is also possible to quickly close the valve by passing an electric current through it, but in this case, the electromagnetic safety valve f, which is opened in conjunction with the ignition operation, is connected to the thermal lightning element e.
Until a predetermined electromotive force is generated, the valve is held open by the power supplied from the power supply C through the transistors i and j by the operation of the timer circuit g and the flame detection circuit. d is charged, and this charging reduces the capacity of capacitor d during fire extinguishing operations.
A large capacitance capacitor d is required, and since the degree of reduction in capacity is not constant, the thermoelectric element e
There are inconveniences such as the length of time the current flows to cancel the electromotive force is not constant.

(Means for Solving the Problems) The present invention aims to provide a device that eliminates the above-mentioned disadvantages, and includes an electromagnetic safety valve interposed in a fuel supply path to a burner, a timer circuit, and an electromagnetic safety valve. The electromagnetic safety valve is opened in conjunction with the ignition operation, and the timer circuit is operated for a certain period of time until a predetermined electromotive force is generated from the thermoelectric element. When the predetermined electromotive force is generated, the valve is held in the open state by this electromotive force to continue combustion of the burner, and the direction in which the electromotive force of the thermoelectric element is canceled out. A switching element is interposed and connected to the circuit, a capacitor is provided that is charged or discharged only during a fire extinguishing operation, and the switching element is made conductive by charging or discharging the capacitor. shall be.

(Function) The present invention has the above configuration, and according to this, the capacitor is charged or discharged only during a fire extinguishing operation, and this charging or discharging causes a current to flow in the direction of making the switching element conductive and canceling the electromotive force of the thermoelectric element. Since the electromagnetic safety valve is closed quickly by flowing the capacitor, the capacitor will not be charged or discharged during the ignition operation, and therefore, the capacity will not be reduced during the extinguishing operation.

(Example) Next, an example of implementation in which the present invention is applied to a gas water heater will be described based on the drawings.

In the drawing, 1 is a main burner, 2 is an ignition burner, and 3 is a constant fire burner, and the gas supply path 4 to the main burner includes a manually opened electromagnetic safety valve 5, a hydraulic response valve 6, and a pressure regulating valve 7. are interposed, and the electromagnetic safety valve 5 and the water pressure responsive valve 6 of the gas supply path 4
The ignition burner 2 and the permanent burner 3- are branched from between.
An on-off valve 9 for an ignition burner and an on-off valve 10 for a regular burner are interposed in the gas supply path 8 . Furthermore, the ignition burner 2
A spark plug 11 is provided facing the burner 3, and a thermocouple 12 as a thermoelectric element and a flame rod 1 are provided on the burner 3.
3 will be set up facing you.

Reference numeral 14 indicates a heat exchanger heated by the main burner 1, and the water supply channel J5 of the heat exchanger 14 has a water flow valve 16 and a pressure regulating valve 17.
and a water governor 18 are provided.

The water pressure responsive valve 6 is opened by a water governor 18 that is displaced when the water flow valve 16 is opened.

Here, 34 is the hot water release/stopping button, and the electromagnetic safety valve 5
, the ignition burner on-off valve 9, the regular burner on-off valve 10, and the water flow valve 16 are opened manually.

35 is a water supply/stop button, and a hot water supply/stop button 34
Regardless of this, the water flow valve 16 is manually opened by an independent operation.

The functions described in "2" by operating these buttons 34 and 35 are widely known from Utility Model Publication No. 133-99158.

Reference numeral 19 indicates a thermocouple for detecting oxygen deficiency provided on the exhaust port side (not shown). Next, a control circuit for the gas water heater having the above configuration will be explained.

The electromagnetic safety valve 5 has a double-wound coil 20 with low power consumption, one coil 20a of which is connected to the thermocouple 12 heated by the permanent burner 3, and the other coil 20.
b is connected to a battery 2I serving as a power source.

An ignition circuit 23, a timer circuit 24, and a flame detection circuit 25 were sequentially provided in a circuit 22 connecting the coil 20b to a battery 21.

The ignition circuit 23 is operated by an ignition switch 26 which is closed only during ignition operation, causing the ignition plug 1 to generate a spark for a predetermined period of time.

The timer circuit 24 is actuated by a changeover switch 27 connected to a lower terminal 27a during an ignition operation to turn on a transistor 28 for a certain period of time.

The flame detection circuit 25 is prepared for operation by the conduction of the transistor 28 due to the operation of the timer circuit 24, and is activated when the conventional burner 3 is ignited and current flows through the flame rod 13, and the transistor 29 is activated. Make conductive.

When doing so, the electromagnetic safety valve 5 and the on-off valves 9 and 10 are opened by tapping the hot water, gas is supplied to the ignition burner 2 and the regular fire burner 3, and the ignition switch 26 is closed, causing the ignition circuit 23 to open for a predetermined period of time. At the same time, the selector switch 27 is connected to the lower terminal 27a to start the timer circuit 24 for a certain period of time, and the ignition burner 2 is ignited by the spark from the ignition circuit 23. When the constant flame burner 3 ignites, the flame detection circuit 25 is activated and the voltage of the battery 21 is changed to the transistor 2829.
The electromagnetic safety valve 5 is supplied to the coil 20b of the electromagnetic safety valve 5 via the timer circuit 24, and the electromagnetic safety valve 5 is kept open for a certain period of time by the timer circuit 24. The coil 20a is energized by a predetermined electromotive force and held in an open state, and combustion of the normally-fired burner 3 is connected. In addition, by the hot water tapping operation described above, the constant fire burner 3
After ignition, the water flow valve 16 is subsequently opened to allow water to flow through, the water pressure response valve 6 is opened due to the displacement of the water governor 18, and the main burner 1 is ignited by the flame transfer from the normally lit burner 3, and the main burner 1 The heat exchanger 14 is heated by this, and hot water is obtained from the hot water supply path 30.

Note that the on-off valve 9 is opened only when the hot water is tapped, and the ignition burner 2 is maintained in the extinguished state after the hot water tapping operation.

In addition, when the constant flame burner 3 does not ignite during the hot water tapping operation, the flame detection circuit 25 detects the non-ignition, the voltage of the battery 21 is not supplied to the coil 20b, and the electromagnetic safety valve 5 is not held open and is in the extinguished state. maintained.

It should be noted that the changeover switch 27 is configured to return to the upper terminal 27b when the hot water tap/finishing button 34 is used to lift the hot water.

In addition, the thermocouple 12 and the thermocouple 19 are connected with opposite polarity to each other, and this is connected to the coil 20a, so that when the main burner 1 suffers from poor combustion due to an oxygen deficiency, etc., the thermocouple 19 is connected to the thermocouple 19. Make sure that an electromotive force is generated in the opposite direction to 2.
The electromotive force of both 1.2.1.9 is canceled out and the electromagnetic safety valve 5
is closed.

3 is a reverse current circuit 31 that flows a current in the direction of canceling the electromotive force of the thermocouple 12. A transistor 32 as a switching element is connected to the circuit 31, and a capacitor 33 is provided which is charged only during extinguishing operation. By charging the capacitor 33, the transistor 32 is made conductive. In addition, in this case, the tiger> desta 32 and the capacitor 3
342411 has been prepared to improve reliability.

When hiding, use the extinguishing operation to turn off the selector switch 27.
When the capacitor 33 is returned to the upper terminal 27b, the battery 21 charges the capacitor 33, and during charging, the transistor 3
2 is made conductive, the circuit 31 becomes a closed circuit, and a current shown by a dotted line flows through the coil 20b in the circuit 31 in the direction of canceling the residual electromotive force from the thermocouple 12 after the hoisting operation, and the electromagnetic safety valve 5 is immediately closed. Incidentally, when the changeover switch 27 is connected to the lower terminal 27a by the next ignition operation, the capacitor 33 is discharged and then the potentials at both ends thereof become equal, and the capacitor 33 is not charged.

In the above-mentioned embodiment, the electromagnetic safety valve 5 is quickly closed during the hoisting operation, so the constantly burning drumstick 3 is quickly extinguished, and the water outlet operation is performed using the water outlet/stop button 35 immediately after the hoisting operation. This is advantageous because even if the water pressure responsive valve 6 is opened, no gas will flow out, that is, there is no risk of explosion and ignition during subsequent hot water tapping operations.

In the embodiment described above, when the capacitor 33 is charged, a current flows in a direction that cancels out the predetermined electromotive force from the thermocouple 12, but when the capacitor is discharged, the predetermined electromotive force from the thermocouple 12 is caused to flow. It is also possible to flow a current in a direction that cancels out the current.

Although the above-mentioned embodiment is a case of a gas water heater, the present invention can be applied to any combustor as long as it is equipped with an electromagnetic safety valve.

(Effects of the Invention) As described above, according to the present invention, the electromagnetic safety valve is closed by passing a current in the direction of canceling the electromotive force of the thermoelectric element during fire extinguishing operation. The electromagnetic safety valve has the effect of closing the electromagnetic safety valve quickly compared to the above, and furthermore, the switching element is made conductive by charging or discharging the capacitor that is charged or discharged only during fire extinguishing operations, thereby canceling the electromotive force of the thermoelectric element. Since the current is made to flow in the same direction, the capacitance of the capacitor can be made smaller than those equipped with a capacitor that is charged not only during extinguishing operations but also during ignition operations, and the current can be reliably passed for a certain period of time. It has the effect of

[Brief explanation of drawings]

Fig. 1 is a gas system diagram showing one example of implementation when the present invention is applied to a water heater, Fig. 2 is its control circuit diagram, Fig. 3 is a cutaway side view of the gas valve portion, and Fig. FIG. 4 is a control circuit diagram considered during the creation process of the present invention. 1... Main burner 2... Ignition burner 3...
Constant fire burner (burner) 4.8...Gas supply path 5...Solenoid safety valve 1
2... Thermocouple (thermoelectric element) 31... Reverse current circuit 3z... Transistor (switching element) 33...
・Condenser 34...Hot water supply/stop button 35...Water supply/stop button 1 2

Claims (1)

[Claims] The electromagnetic safety valve is equipped with an electromagnetic safety valve interposed in the fuel supply path to the burner, a timer circuit, and a thermoelectric element connected to the coil of the electromagnetic safety valve and heated by the burner. The safety valve is maintained in an open state by operating the timer circuit for a certain period of time until a predetermined electromotive force is generated from the thermoelectric element, and when the predetermined electromotive force is generated, the safety valve is maintained in an open state by this electromotive force. A capacitor configured to continue combustion in the burner, provided with a circuit that flows a current in a direction to cancel the electromotive force of the thermoelectric element, a switching element connected to the circuit, and charged or discharged only during extinguishing operations. A control device for a combustor, characterized in that the switching element is made conductive by charging or discharging the capacitor.