JP2000249329A - Ignition controller for petroleum water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress combustion sound, vibration, incompletely burned gas or smoke when a petroleum water heater is ignited. SOLUTION: Combustion air is supplied by a blower 2, fuel pressurized by an electromagnetic pump 1 is sprayed in a foggy state, and the foggy fuel is ignited by a discharge spark of a discharge igniter 3. A current amount control means 6 is provided at the pump 1, and a specified spraying fuel amount is obtained by gradually enhancing a discharge pressure of the pump 1 from an igniting time under the control of the current amount. A solenoid valve 4 for preventing a reverse flow of fuel discharged when the pump 1 is stopped is provided. The valve 4 is variably changed from small amount to a normal current amount of the current supplied by a current flow control means 6a, and a current amount when ignited is suppressed so that chattering is brought about at the valve 4. The burner 7 is ignited when the chattering occurs, the current amount of the valve 4 is increased after the ignition to prevent the chattering, and hence a combustion sound after the ignition is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition control device which suppresses combustion noise and vibration at the time of ignition of an oil hot water heater and generation of incomplete combustion gas and smoke.

[0002]

2. Description of the Related Art A pressure spray burner used as a heat source of an oil hot water heater sends an amount of air blown by a blower, a fuel flow rate pressurized by an electromagnetic pump and blown out from a spray nozzle to a burner, and a discharge ignition device. Since ignition and combustion are instantaneously started by a spark generated from the discharge electrode, at the time of ignition, sound and vibration close to explosion sound are generated, and odor and smoke related to incomplete combustion are generated.

[0003] For this reason, the electromagnetic pump is designed to reduce the air flow rate and the fuel flow rate so that the burner at the time of ignition can be completely burned, mainly with the aim of gradually increasing the discharge pressure (flow rate) by means of a current control means such as phase control. There is a proposal of a soft-ignition device for controlling the ignition at a low fuel flow rate and thereafter increasing the output to 100%. (See No. 59-13480)

[0004]

In an oil water heater using a pressure spray burner, reducing noise and vibration at the time of ignition involves igniting at a small fuel flow rate, and thereafter gradually increasing the amount of combustion. In order to reduce odor and smoke at the time of ignition, it is necessary to control and supply the amount of air so that the increased fuel flow can be completely burned.

The electromagnetic pump used for this pressure spray burner is designed so that the discharge pressure is usually used at about 7 to 9 kgf / cm 2 in consideration of the discharge capacity and the inner diameter of the spray nozzle, so that the ignition and normal combustion are performed. The average discharge flow rate can be gradually increased by controlling the fuel flow rate up to the phase control or the like, and the combustion noise of the dawn at the time of ignition can be suppressed.

However, in a state where the discharge capacity of the electromagnetic pump is suppressed, there is a case where the fluctuation of the discharge pressure becomes large due to the pressure remaining on the discharge side due to the influence from the spray nozzle and the piping. If ignition occurs in the presence of pressure fluctuation, ignition can be performed with a small discharge flow rate, but the combustion noise after ignition becomes abnormally large due to the pressure fluctuation. For this reason, if this pressure fluctuation is suppressed and the pressure is gently increased by improving the power supply control means or attaching an accumulator to the piping, the average discharge pressure that can ignite reliably increases, and the combustion volume at the time of ignition There is a problem that the ignition sound of the dawn cannot be lowered when the size becomes large.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and comprises an electromagnetic pump 1 for supplying fuel and a blower 2 for supplying combustion air, and a fuel flow rate discharged from the electromagnetic pump 1 at the time of ignition. While increasing the normal fuel flow rate while balancing the air flow rate blown from the blower 2,
A water heater that is provided with a discharge igniter 3 for igniting spray fuel by a spark to be discharged, ignited by the discharge igniter 3 when the fuel flow rate is smaller than the normal fuel flow rate, and increasing the fuel flow rate together with the air flow rate to the normal fuel flow rate after ignition In the soft ignition device, an electromagnetic valve 4 for stopping the flow of fuel when the electromagnetic pump 1 is stopped is provided, and ignition control means 5 for controlling the electromagnetic pump 1, the blower 2, and the discharge of the discharge ignition device 3 is provided. The ignition control means 5 includes an electromagnetic valve 4 like the electromagnetic pump 1.
In addition, the solenoid valve 4 generates chattering based on the suppressed amount of current by outputting the current control signal, and the ignition control means 5 controls the electromagnetic pump 1 so that the ignition point is set immediately before the chattering of the solenoid valve 4 is eliminated. Alternatively, it is configured to control the blower 2 or the discharge ignition device 3.

The electromagnetic pump 1 and the electromagnetic valve 4 controlled by the ignition control means 5 are controlled to be energized by the same energization amount control means 6, and the ignition control means 5 controls the electromagnetic pump 1 immediately before the chattering of the electromagnetic valve 4 is eliminated. The ignition flow is controlled by controlling the blower 2 or the discharge igniter 3 in accordance with the discharge flow rate. Since it can be reduced, the combustion noise after ignition can be reduced.

A burner 7 to which fuel and air are supplied from the electromagnetic pump 1 and the blower 2 is provided with an ignition detecting means 7a. The power supply is controlled by the control means 6, 6a, and the power supply amount control means 6a of the solenoid valve 4 supplies a specific power supply amount at which strong chattering occurs at the time of ignition, and a normal time when the ignition detection means 7a detects the ignition. If the configuration is set so as to return to the maximum energization amount, the chattering of the electromagnetic valve 4 is optimal for ignition and can be ignited while the discharge amount of the electromagnetic pump is small. Quiet ignition was possible without generating any sound.

[0010]

When an electromagnetic pump having no shutoff capability is used, an electromagnetic valve for stopping the flow of fuel when the electromagnetic pump is stopped is provided. The electromagnetic valve is energized from an ignition operation to a fire extinguishing operation. It is common to keep the circuit open. On the other hand, in order to reduce the ignition sound, ignition is performed when the spray pressure is low, and the pressure is gradually increased. At this time, the ignition spreads more widely than the stable spray fuel. Can be ignited at low pressure. But,
Variation in the spread of fuel means that the combustion noise after ignition becomes abnormally large.

The present invention utilizes the chattering of the solenoid valve 4 in order to vary the spread of the sprayed fuel. If the amount of power supplied to the solenoid valve 4 is reduced, the suction state cannot be maintained and the solenoid valve 4 repeatedly opens and closes. By setting the ignition point before this chattering does not occur, the spread of fuel is dispersed at the time of ignition to make it easier to ignite, and after ignition, the combustion noise can be suppressed by spray fuel in a stable state. Was.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to an embodiment of a heater shown in FIG. 1. Numeral 1 denotes an electromagnetic pump for supplying fuel to a burner 7, and numeral 8 sprays the fuel pressurized by the electromagnetic pump 1 in atomized form. The spray nozzle 3 is a discharge ignition device whose tip is disposed in front of the spray nozzle 8, and 2 is a blower for supplying combustion air to the burner 7.

9 is a blower control means for controlling the rotation of the blower 2; 6 is a flow control means for changing the amount of power supplied to the electromagnetic pump 1 to change the discharge capacity of the electromagnetic pump 1;
In the case of an AC power supply, this is performed by a phase control circuit, and in the case of a DC power supply, a pulse frequency changing circuit is used.

Reference numeral 10 denotes a burner controller for performing ignition, fire extinguishing, and other various safety operations of the burner 7, and reference numeral 5 denotes ignition control means for mainly controlling the ignition of the burner controller 10, and the electromagnetic pump 1, the blower 2, and the like. Controlling the discharge ignition device 3 and the like enables stable ignition.

Reference numeral 11 denotes a combustion chamber into which the flame of the burner 7 is blown, 12 denotes a heat exchange chamber following the combustion chamber 11, 13 denotes an exhaust pipe for discharging combustion exhaust gas passing through the heat exchange chamber 12, and 14 denotes a combustion chamber. The water chamber constitutes a can body of a water heater that covers the outside of the heat exchange chamber 12, and the water chamber 14 is provided with a water supply pipe 14 a and a hot water supply pipe 14 b.

Reference numeral 15 denotes ignition means for instructing the burner controller 10 to start the oil hot water heater, 16 denotes fire extinguishing means for instructing the operation of the oil hot water heater to stop, and 17 denotes a water chamber 14 of the hot water heater.
When the water heater is started by the ignition means 15, the burner controller 10 acts on the ignition control means 5 while detecting the hot water temperature by the hot water temperature detection means 17. When the hot water temperature detecting means 17 detects the set temperature, the operation of the burner 7 is stopped. Since the inside of the water chamber 14 is heated to a constant temperature in this manner, the water sent from the water supply pipe 14a becomes hot water and can be taken out from the hot water supply pipe 14b.

In an oil water heater equipped with such a pressure spray burner, the fuel can be ignited even when a normal fuel flow rate and an air flow rate are sent to the burner 7 from the time of the ignition operation. The internal pressure of the combustion chamber 11 in the limited space becomes high immediately after the ignition, and generates a combustion start sound and vibration called "dawn" and also generates smoke and odor. As a countermeasure, the amount of fuel sent to the spray nozzle 8 by the power supply amount control means 6 of the electromagnetic pump 1 and the air supply control means 9 of the blower 2 is reduced immediately after the ignition operation, and an air amount capable of igniting in a balanced manner even with this small fuel flow rate is obtained. By performing such control, a soft ignition device that ignites when the amount of combustion is small and suppresses a rise in pressure in the combustion chamber 11 has been put to practical use.

By the way, when the electromagnetic pump 1 is operated to obtain a normal fuel flow rate, the fuel to be discharged and the diameter of the spray nozzle 8 are balanced to maintain a pressure of 7 to 9 kgf / cm 2. When the discharge pressure (fuel flow rate) is reduced by using the power supply amount control means 6, the balance is broken and the fuel is easily released due to the operation of the electromagnetic pump 1 and the shape of the piping, and conversely, the piston of the electromagnetic pump 1 When the fuel is pushed, the piston may return immediately while the fuel is not sufficiently pushed out, and the fluctuation of the discharge pressure may increase.

If the pressure fluctuates greatly as described above, the pattern of the fuel ejected from the spray nozzle 8 also varies, so that the point of the optimum fuel-air flow rate ratio for ignition is easily generated, and ignition is possible even at a low discharge pressure. However, if the fuel pressure fluctuates after ignition, there is a problem that the combustion noise increases. On the other hand, the discharge pressure can be increased in a stable state by changing the method of the pipe line and the amount-of-current control means 6, or by attaching the accumulator 18, for example.
At this time, it becomes difficult to ignite because the pattern of the ejected fuel is stable, and since there is a lot of fuel when ignition is possible, a loud ignition sound such as a dawn is likely to occur.

The present invention aims at suppressing ignition noise and vibration after ignition while enabling ignition when the discharge pressure at the time of ignition of the electromagnetic pump 1 is low. 4 is an electromagnetic valve for stopping the flow of fuel when the electromagnetic pump 1 is stopped, 6a
Is a power supply control means for the solenoid valve 4. The solenoid valve 4 may be attached to the electromagnetic pump 1 or attached to a pipe line. This type of solenoid valve 4 is normally ON / OFF controlled. Control means 6
a is attached so that the amount of electricity can be suppressed. When the amount of electricity is suppressed, the solenoid valve 4 cannot maintain a closed circuit even when energized, and causes chattering. Since the fuel flow path opens and closes, the amount of fuel discharged to the burner 7 is large. It varies.

The chattering of the solenoid valve 4 is stopped when the amount of current supplied to the solenoid valve 4 by the internal spring or plunger is stopped, and the suction is maintained. Since the electromagnetic valve 4 has been switched to an energizing amount that does not cause chattering, ignition can be performed when the discharge amount of the electromagnetic pump 1 is small, and combustion noise after ignition can be kept low.

As a specific embodiment, the circuits of the electromagnetic pump 1 and the electromagnetic valve 4 are connected in parallel to use the power control means 6, and the power control means 6 gradually increases the normal fuel flow from the stop of the fuel. At the same time, the electromagnetic valve 4 generates chattering immediately after energization, and the chattering stops when the electromagnetic pump 1 reaches a certain flow rate. Therefore, the ignition control means 5 controls the discharge igniter 3 and the blow control means 9 of the blower 2 so that the ignition can be performed at the fuel flow just before the chattering of the solenoid valve 4 stops, so that the chattering of the solenoid valve 4 can be performed. The control is performed in which the ignition is performed and the chattering of the solenoid valve 4 is stopped after the ignition.

In another embodiment, reference numeral 7a designates an ignition detection means constituted by CdS or the like for detecting the brightness of the combustion flame of the burner 7, and an energization amount control means 6 attached only to the solenoid valve 4.
“a” is set to the amount of current that causes a change in the discharge pressure optimal for ignition. If an ignition operation is performed by the ignition control means 5 in this state, the ignition can be performed even at 1 kgf / cm 2 or less because the discharge pressure varies in this case.
When the ignition occurs, the ignition detection means 7a detects this and sets the energization of the solenoid valve 4 to the normal state.
Charging stopped reliably, and a quiet ignition became possible.

[0024]

As described above, according to the present invention, the conventional ON / O
A small amount of electricity controlled by the electricity amount control means 6a is supplied to the FF controlled electromagnetic valve 4 to forcibly cause chattering to fluctuate the discharge pressure of the electromagnetic pump 1, and the ignition control means 5 Since the ignition is controlled so that the ignition can be performed during the ignition, the ignition can be performed when the discharge pressure of the electromagnetic pump 1 is considerably low.

Further, since the chattering of the solenoid valve 4 can be stopped immediately by increasing the amount of energization of the energization amount control means 6a, if the chattering of the solenoid valve 4 is stopped after ignition, The ignition is performed at a low discharge pressure of the electromagnetic pump 1, and after the ignition, the discharge pressure of the electromagnetic pump 1 is stabilized and a quiet ignition is possible without generating an ignition sound such as a dawn.

Since the amount of energization at which chattering of the solenoid valve 4 stops is determined by the characteristics of the components used in the solenoid valve 4, the same energization amount control means 6 can be selected by focusing on only the ignition point by selecting the solenoid valve 4. Can be used, and by omitting the power supply control means 6a dedicated to the solenoid valve 4, a petroleum water heater with a low ignition sound can be realized without a large increase in cost.

Furthermore, if the chattering of the solenoid valve 4 can be maintained in an optimum state for ignition, the ignition becomes possible even when the discharge amount of the electromagnetic pump 1 is very small, and the chattering is immediately stopped when the ignition is confirmed. By doing so, it is possible to achieve a quieter ignition.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an oil water heater according to an embodiment of the present invention.

FIG. 2 is a sectional view of an oil hot water heater showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electromagnetic pump 2 Blower 3 Discharge igniter 4 Solenoid valve 5 Ignition control means 6 Electricity control means 6a Electricity control means 7 Burner 7a Ignition detection means

Claims (3)

[Claims] An electromagnetic pump (1) for supplying fuel and a blower (2) for supplying combustion air are provided, and the fuel flow discharged from the electromagnetic pump (1) at the time of ignition and the air flow blown from the blower (2) are balanced while the normal fuel flow is maintained. To increase,
A water heater that is provided with a discharge igniter 3 for igniting spray fuel by a spark to be discharged, ignited by the discharge igniter 3 when the fuel flow rate is smaller than the normal fuel flow rate, and increasing the fuel flow rate together with the air flow rate to the normal fuel flow rate after ignition In the soft ignition device, an electromagnetic valve 4 for stopping the flow of fuel when the electromagnetic pump 1 is stopped is provided, and the electromagnetic pump 1, the blower 2, and the discharge ignition device 3 are provided.
Ignition control means 5 for controlling the electric discharge of the electromagnetic valve 4. The ignition control means 5 outputs an electric current control signal to the electromagnetic valve 4 as well as the electromagnetic pump 1 to generate chattering in the electromagnetic valve 4 by the suppressed electric current. And the ignition control means 5 sets the ignition point immediately before the chattering of the solenoid valve 4 is eliminated,
Electromagnetic pump 1 or blower 2 or discharge ignition device 3
Ignition control device for oil hot water heater that controls the water. 2. The electromagnetic pump 1 controlled by the ignition control means 5 and the electromagnetic valve 4 are energized by the same energization amount control means 6 and the ignition control means 5 controls the electromagnetic pump 1 immediately before the chattering of the electromagnetic valve 4 is eliminated. The ignition control device according to claim 1, wherein the ignition is performed by controlling the blower (2) or the discharge ignition device (3) in accordance with the discharge flow rate of the oil. 3. A burner 7 to which fuel and air are supplied from an electromagnetic pump 1 and a blower 2 is provided with an ignition detecting means 7a. The power supply is controlled by the control means 6, 6a, and the power supply amount control means 6a of the solenoid valve 4 supplies a specific power supply amount at which strong chattering occurs at the time of ignition, and a normal time when the ignition detection means 7a detects the ignition. 2. The ignition control device for an oil hot water heater according to claim 1, wherein the ignition amount is returned to the maximum energization amount.