JPH0933036A - Boiler for performing adjustment of air supplying volume in ignition time - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a flame at the time of ignition for a boiler from being blown off and to enable a positive ignition to be carried out. SOLUTION: This boiler is provided an air supplying volume adjusting device 11 connected to a combustion control device 7 which is comprised of a blower 3 for supplying air to a burner of a boiler 1, an air passage 4 connecting the blower 3 with the burner, a damper 5 placed in the midway part of the air passage 4 and for adjusting an air volume supplied to the burner through adjustment of its degree of opening, and a damper control device 6 for adjusting a degree of opening of the damper to a value more narrow than that applied for a normal combustion at the time of ignition at the burner, wherein an air volume supplied at the time of ignition of the burner is set to be an air volume exclusively applied for ignition lower than an air volume supplied at the time of normal combustion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiler that stabilizes ignition by adjusting the amount of air supplied during ignition.

[0002]

2. Description of the Related Art In the case of a boiler in which the combustion amount of a burner is controlled in three positions: high combustion, low combustion, and stop, the required amount of combustion air differs depending on the combustion amount. A damper was installed in the middle of the connecting wind path to achieve high combustion,
The opening amount of the damper is set for each of low combustion and stop, and the opening amount of the damper is adjusted according to the combustion amount to adjust the combustion air amount. When igniting the burner, the damper is ignited at a low combustion opening with a relatively small amount of air supply, but due to too much air, the flame is blown out before the flame stabilizes, resulting in no ignition. Was sometimes.

[0003]

The problem to be solved by the present invention is to prevent the flame from being extinguished during ignition,
It is to ensure that ignition can be performed.

[0004]

A blower for supplying air to a burner, a fuel supply device for supplying fuel to the burner, an ignition device for generating a spark in a mixture of air and fuel injected from the burner, and combustion control of the burner. In a boiler equipped with a combustion control device, a damper that adjusts the amount of air that is supplied to the burner by adjusting the opening in the middle of the air passage that connects the blower and the burner, and the damper opening when the burner is ignited Connected to the combustion control device, which is composed of a damper control device that adjusts narrowly and is connected to the combustion control device, or when the burner is ignited, the rotation speed of the motor that operates the blower is adjusted to be lower than during normal combustion. By installing the specified air supply amount adjusting device, the amount of air supplied during burner ignition is less than the amount of air supplied during normal combustion To.

[0005]

[Operation] Since the air volume at the time of ignition is set to an air volume suitable for ignition,
It is possible to reliably ignite the flame because the flame is not extinguished due to an excessive amount of air.

[0006]

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an outline of a boiler according to claim 1. The burner is provided in the upper part of the boiler 1, and a damper 5 is provided in the middle of an air passage 4 that sends combustion air from the blower 3 to the burner. The opening degree of the damper 5 is adjusted by the damper control device 6 connected to the damper 5, and the damper 5 is kept constant by the cam and the limit switch provided on the rotary shaft of the motor that drives the damper of the damper control device 6. A signal is transmitted when rotating by an angle, and the opening of the damper 5 is set to each of the opening at ignition, the low combustion opening, the high combustion opening and the fully closed opening. The device 6 constitutes the air supply amount adjusting device 11. Each damper opening degree is an opening degree at ignition <low combustion opening degree <high combustion opening degree, and the larger the opening degree, the larger the amount of air passing through the damper portion and the larger the amount of supplied air. A combustion control device 7 for controlling combustion includes a first solenoid valve 9 for supplying fuel to the burner during combustion and a second solenoid valve 8 for supplying fuel to the burner during high combustion, an ignition device 10, a blower 3, and a damper control device 6. , And the pressure switch 2 which outputs the pressure of the steam portion, respectively, and performs combustion control at three positions of high combustion, low combustion, and stop.

FIG. 2 shows the opening of the damper and the operation of each device in one embodiment according to claim 1. When it is output that the steam pressure is lower than the high pressure side set pressure of the pressure switch, the combustion control device 7 starts combustion. The damper 5, which was fully closed during the stop, operates the motor of the damper control device 6 to have a high combustion opening, and operates the blower 3 to ventilate the inside of the furnace. Next, the motor of the damper control device 6 is operated so that the opening of the damper 5 becomes the opening during ignition, the ignition device 10 is energized to generate a spark, and the first solenoid valve 9 is opened to perform ignition. . Since the opening degree of the damper 5 is set to the opening degree for ignition, which is set only for ignition, the amount of air sent from the blower can be adjusted to an optimum amount and reliable ignition can be achieved. After that, the opening degree of the damper 5 is set to a low combustion opening degree, and low combustion is performed for a certain period of time. At this time, if the steam pressure is lower than the low pressure side set pressure of the pressure switch 2, the damper 5 opening is set to a high combustion opening and the second solenoid valve 8 is opened to perform high combustion. If the vapor pressure rises and rises above the low pressure side set pressure of the pressure switch 2, the opening of the damper 5 is set to a low combustion opening and the second solenoid valve 8 is closed to perform low combustion,
When the steam pressure further rises to stop combustion, the first solenoid valve 9 is closed, the damper opening is set to a high combustion opening to ventilate the inside of the furnace, and then the blower 3 is stopped and the damper 5 is opened.
Combustion is stopped by fully closing the opening.

FIG. 3 shows an outline of the boiler according to claim 2. The burner is provided in the upper part of the boiler 1, and the blower 3 supplies a combustion air to the burner by rotating a fan with a DC motor. The voltage supplied to the blower 3 is adjusted by the voltage adjusting device 12, and the voltage is set to each of the ignition voltage, the low combustion voltage, and the high combustion voltage, and the voltage adjusting device 12 causes the air supply amount adjusting device to operate. It will be 11. Each set voltage is a voltage at ignition <low combustion voltage <high combustion voltage, and the higher the voltage, the more the rotation speed of the fan and the larger the amount of supplied air. A combustion control device 7 for controlling combustion includes a first solenoid valve 9 for supplying fuel to a burner during combustion.
And a second solenoid valve 8 for supplying fuel to the burner during high combustion, an ignition device 10, a voltage adjusting device 12, a pressure switch 2
The combustion control is performed at three positions of high combustion, low combustion, and stop.

FIG. 4 shows the blower supply voltage and the operating state of each device in one embodiment relating to claim 2. When it is output that the steam pressure is lower than the high pressure side set pressure of the pressure switch, the combustion control device 7 starts combustion.
First, a high combustion voltage is supplied to the blower to ventilate the inside of the furnace. Next, the voltage supplied to the blower 3 is controlled by the voltage adjusting device 12 so as to be the voltage at the time of ignition to reduce the rotation speed of the fan, and the ignition device 10 is energized to generate a spark, and the first electromagnetic valve 9 is opened and ignition is performed. Since the voltage supplied to the blower is the ignition voltage set for ignition only, the amount of air sent from the blower can be adjusted to an optimum amount, and reliable ignition can be achieved. After that, the blower voltage is set to a low combustion voltage and low combustion is performed for a certain period of time. At this time, if the steam pressure is lower than the low pressure side set pressure of the pressure switch 2, the blower voltage is set to a high combustion voltage, and the second solenoid valve 8 is opened to perform high combustion. If the steam pressure rises and rises above the low pressure side set pressure of the pressure switch 2, the blower voltage is set to a low combustion voltage, the second solenoid valve 8 is closed to perform low combustion, and the steam pressure rises and combustion is stopped. In that case, the first solenoid valve 9 is closed, the blower voltage is set to a high combustion voltage to ventilate the inside of the furnace, and then the blower 3 is stopped.

Even if the motor of the blower 3 is an AC motor and the frequency supplied to the blower is adjusted by the frequency adjusting device instead of adjusting the voltage supplied to the blower by the voltage adjusting device, the same effect can be obtained. Can be

[0011]

By implementing the present invention, it is possible to prevent the flame from being blown out due to an excessive amount of air during burner ignition, and it is possible to carry out stable ignition.

[Brief description of drawings]

FIG. 1 is a schematic view of a boiler according to an embodiment of claim 1 of the present invention.

FIG. 2 is a control sequence diagram in an embodiment according to claim 1 of the present invention.

FIG. 3 is a schematic view of a boiler according to an embodiment of claim 2 of the present invention.

FIG. 4 is a control sequence diagram in an embodiment according to claim 2 of the present invention.

[Explanation of symbols]

 1 Boiler 2 Pressure Switch 3 Blower 4 Airway 5 Damper 6 Damper Control Device 7 Combustion Control Device 8 High Combustion Solenoid Valve 9 Low Combustion Solenoid Valve 10 Ignition Device 11 Air Supply Adjustment Device 12 Voltage Adjustment Device

Claims (3)

[Claims] 1. A blower for supplying air to a burner, a fuel supply device for supplying fuel to the burner, an ignition device for generating a spark in a mixture of air and fuel injected from the burner, and a combustion control device for controlling combustion of the burner. In the installed boiler,
Combustion consists of a damper that adjusts the amount of air supplied to the burner by adjusting the opening in the airway that connects the blower and the burner, and a damper control device that adjusts the damper opening to a smaller value during normal combustion than during normal combustion. A boiler for adjusting an air supply amount at the time of ignition, which is provided with an air supply amount adjusting device connected to a control device. 2. A blower for supplying air to the burner, a fuel supply device for supplying fuel to the burner, an ignition device for generating a spark in a mixture of air and fuel injected from the burner, and a combustion control device for controlling combustion of the burner. In the installed boiler,
When the burner is ignited, it has a voltage adjustment device that adjusts the voltage supplied to the motor that operates the blower to less than that during normal combustion.
A boiler for adjusting an air supply amount at the time of ignition, which is provided with an air supply amount adjusting device connected to a combustion control device. 3. The boiler for adjusting the air flow rate at the time of ignition according to claim 2, wherein an air supply amount adjusting device having an inverter for changing the frequency of the alternating current is provided instead of the voltage adjusting device. A boiler that adjusts the amount of air supplied during ignition.