JPH0351656Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a combustion control device for a combustor. Conventionally, as this type of product, for example,
In the device disclosed in Publication No. 114886, the igniter is operated using a charged capacitor as a power source, so as the charge in the capacitor is discharged, the terminal voltage of the capacitor gradually decreases, and as a result, the interval between spark discharges of the igniter decreases. becomes longer. If air is mixed in the rubber tube, and the igniter is discharged during the time between when the air is expelled and the gas is ejected from the nozzle, a phenomenon similar to ignition delay will occur. This is accompanied by the inconvenience of increased ignition noise.

Furthermore, for example, the method disclosed in Japanese Utility Model Application Publication No. 56-42672 involves intervening the contact point of a relay that is time-activated by a capacitor charged by a battery power source in the connection circuit between the battery power source, the solenoid of the electromagnetic safety valve, and the igniter. Therefore, as long as the battery power supply does not deteriorate, the interval between spark discharges of the igniter will not become long and the above-mentioned inconvenience will be resolved. ,
If the relay contacts are welded and the igniter does not operate normally, raw gas will continue to be emitted, resulting in the inconvenience.

Therefore, in order to eliminate this inconvenience, the electrical charge of the capacitor 2 is discharged via the changeover switch 21 by the ignition operation of the manual operation member 1, and the discharge current is transferred to the electromagnetic safety valve 5 intervening in the gas passage 4 connected to the burner unit 3. A relay 6 operated by the discharge current of the capacitor 2 is provided, and the igniter 7 facing the burner unit 3 is connected to the solenoid 5a to forcibly hold the electromagnetic safety valve 5 in an open state. It is also possible to connect the capacitor 2 to a power source 8 separate from the capacitor 2 through the contact point 6a of the relay 6, which is closed by the operation of the It is conceivable that the capacitor 2 is charged by the power source 8 and the charging current is passed through the solenoid 5a to immediately close the electromagnetic safety valve 5, but simply with such a configuration, the capacitor 2 is The charging current also flows through the relay 6, closing its contact 6a, causing the inconvenience that the igniter 7 is activated.

The purpose of the present invention is to provide a combustion control device that eliminates all of the above-mentioned disadvantages.
The electric charge of the capacitor 2 is discharged through the gas passage 4 connected to the burner unit 3, and the discharge current is passed through the
The electromagnetic safety valve 5 is forcibly held in the open state by supplying current to the solenoid 5a of the electromagnetic safety valve 5 that intervened in the burner unit 3, and the relay 6 having a contact 6a that connects the igniter 7 facing the burner unit 3 to the power source 8. At the same time, the igniter 7 is activated, and the capacitor 2 is charged by the power source 8 via the changeover switch 21 by the extinguishing operation of the manual operation member 1, and the charging current is passed through the solenoid 5a, thereby causing the electromagnetic The safety valve 5 is immediately closed, and is characterized by being provided with an igniter stop means for stopping the operation of the igniter 7 when the capacitor 2 is being charged.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a cutaway plan view of a water heater equipped with a combustion control device of the present invention.

In the same figure, reference numeral 11 denotes a valve rod, and the valve rod 11 is pushed by the first manual operating member 1. A shutoff valve 12 and a shutoff valve 12 are opened at the intermediate position and the end position of the pushing movement, respectively. It is equipped with an ignition valve 13, and is configured to open the electromagnetic safety valve 5 by pressing it via a lever 14 at the end position of the ignition valve 13. Reference numeral 15 denotes a water pressure responsive valve, which responds to the operation of a water flow detector 17 that detects water flow to the heat exchanger 16, and is operated by a push button 18 common to the first manual operation member 1. The water valve 20 connected to the second manual operating member 19 is opened when the push button 18 is pushed to the intermediate position c.

Further, in the figure, reference numeral 21 denotes a changeover switch which is operated by pushing the push button 18 to the intermediate position c by the first manual operation member 1.

In FIG. 2, which shows an electric circuit according to an embodiment of the present invention, when the push button 18 is not operated, the capacitor 2 is connected to the battery, which is the power source 8, through the b contact of the changeover switch 21, and is charged. According to the ignition operation of 18, the discharge circuit 9 is closed via the a contact of the changeover switch 21, and a discharge current is passed through the solenoid 5a of the electromagnetic safety valve 5 that is intervened in the circuit 9, and the electromagnetic safety valve 5 is opened. The system is now forced to hold.

In this known forced hold type circuit, a relay 6 is connected to a discharge circuit 9, and an igniter 7 is connected to a power source 8 via a contact 6a of the relay 6, which is closed for a predetermined time by the discharge current of the capacitor 2. Then, the igniter 7 is activated, and the solenoid 5a of the electromagnetic safety valve 5 is inserted into the charging circuit 25 of the capacitor 2, so that when extinguishing the fire, the charging current of the capacitor 2 is used to turn on the thermoelectric current facing the burner unit 3. The thermoelectromotive current of the pair 23 is canceled out, and the electromagnetic safety valve 5 is quickly closed.

Further, in the operating circuit of the igniter 7, a switch 2 is provided, which is an igniter stop means, which is closed when the igniter is operated, and is opened before the changeover switch 21 is returned to its original state when the extinguisher is operated.
2, even if the charging current of the capacitor 2 flowing through the B contact of the changeover switch 21 flows to the relay 6 and the contact 6a is closed by the extinguishing operation of the push button 18, the switch 22 is already opened; The igniter 7 was prevented from being activated.

A resistor 1 connected in series with the solenoid 5a.
0 is a current limiting resistor whose resistance value is selected so that the electromagnetic safety valve 5 closes before the relay 6 becomes inoperable due to a decrease in discharge current.

Next, to explain its operation, when the common pushbutton 18 is pushed to the terminal position B, the electromagnetic safety valve 5, the cutoff valve 12, and the ignition valve 13 open, and the changeover switch 21 changes from the b contact to the a The electromagnetic safety valve 5 is forcibly held in the open state by the discharge current of the capacitor 2 due to the switching operation to the contact. The relay 6 is activated by the discharge current, and the igniter 7 performs an ignition operation by spark discharge. When the push button 18 is returned to the intermediate position c, the water valve 20 is opened to allow water to flow through the heat exchanger 16, and when the hydraulic response valve 15 is opened, the fuel gas discharged from the burner unit 3 is ignited.

The igniter 7 is operated for a predetermined time, and then the contact 6a of the relay 6 is switched to the b contact side, and the current limiting resistor 10 is short-circuited. The residual charge in capacitor 2 is thus rapidly discharged.

When the push button 18 is returned to position A and the extinguishing operation is performed, the switch 22 is first opened, then the changeover switch 21 is switched to the b contact side, the cutoff valve 12 and the hydraulic response valve 15 are closed, and the burner unit 3 is extinguished. . In this case, the charging current of the capacitor 2 flowing through the b contact of the changeover switch 21 flows to the relay 6 and its contact 6a is closed.
Since the switch 22 is opened before the switch 1 switches to the b contact side, the igniter 7 is not activated.

The circuit shown in the second diagram connects the relay 6 to the solenoid 5a.
Although they are connected in parallel, they may be connected in series as shown in the third diagram. However, relay 6 and solenoid 5a
When the electromagnetic safety valve 5 is inserted in series with the discharge circuit 9, the current flowing through the solenoid 5a becomes small and the electromotive force of the thermocouple 23 reaches a predetermined value.
Since there is a possibility that the valve cannot be kept open, a relay 6 is connected in parallel with the current limiting resistor 10 to reduce the resistance value of the combined resistor so that a large current flows through the solenoid 5a.

The circuits shown in FIGS. 4 and 5 are modified examples of the circuits shown in FIGS. 2 and 3 in which the switch 22 is omitted, respectively, and instead of the switch 22, the relay 6 is connected in series with the igniter stop means. diode 24
was inserted to prevent the charging current of the capacitor 2 from flowing to the relay 6 when the push button 18 is operated to extinguish the fire.

In this way, according to the present invention, the electromagnetic safety valve 5
A relay 6 operated by the discharge current of the capacitor 2 for forcibly holding the valve in the open state is provided, and the igniter 7 facing the burner unit 3 is connected via the contact 6a of the relay 6, which is closed by the operation. Since it is connected to a power source 8 separate from the capacitor 2, it is possible not only to prevent an increase in ignition noise due to a longer time interval between spark discharges of the igniter 7, but also to prevent raw gas from flowing out due to a failure of the igniter 7 or relay 6. It has the effect of eliminating the fear of discharge, and furthermore, since the solenoid 5a of the electromagnetic safety valve 5 is inserted into the charging circuit 25 of the capacitor 2, a charging current is passed through the solenoid 5a during a fire extinguishing operation, and the electromagnetic safety valve 5 is immediately activated. It has the effect of closing the valve and extinguishing the fire.

Furthermore, even if the capacitor 2 is charged during a fire extinguishing operation, an igniter stop means is provided that stops the operation of the igniter 7 during charging, so that the igniter 7 can be reliably kept in an inoperative state. have

[Brief explanation of the drawing]

FIG. 1 is a cutaway plan view of a water heater to which the present invention is applied, and FIGS. 2 to 5 are electrical circuit diagrams of embodiments of the present invention. 1... Manual operation member, 2... Capacitor, 3...
...Burner unit, 4...Gas passage, 5...Solenoid safety valve, 5a...Solenoid, 6...Relay, 7
...Igniter, 8...Power source, 21...Selector switch, 22...Switch (igniter stop means), 24
...Diode (igniter stop means).

Claims (1)

[Scope of utility model registration request] The electric charge of the capacitor 2 is discharged through the changeover switch 21 by the ignition operation of the manual operation member 1, and the discharge current is transferred to the solenoid 5a of the electromagnetic safety valve 5 interposed in the gas passage 4 connected to the burner unit 3.
and a relay 6 having a contact 6a that connects an igniter 7 facing the burner unit 3 to a power source 8, thereby forcibly holding the electromagnetic safety valve 5 in an open state and activating the igniter 7, Furthermore, the capacitor 2 is charged by the power source 8 via the changeover switch 21 by the extinguishing operation of the manual operation member 1, and the electromagnetic safety valve 5 is immediately closed by causing the charging current to flow through the solenoid 5a. , when charging the capacitor 2, the igniter 7
A combustion control device comprising an igniter stop means for stopping the operation of the igniter.