JPH0370910A - Controller for burner - Google Patents

Abstract

PURPOSE:To make good ignitability of fuel when a burner is restarted with high temperature in the carburetor and prevent the accumulation of tar in the carburetor and in the nozzle by changing the supply amount of liquid fuel before ignition according to the temperature of the carburetor. CONSTITUTION:When the operation is started with the temperature of a carburetor 4 at room temperature, it is not over a comparison temperature Tm so that ignition action is taken when the time of t seconds has passed after the operation of an electromagnetic pump 2 is started. On the other hand, when the operation of the carburetor 4 is started while its temperature has not fallen after stopping the combustion, the temperature of the carburetor 4 is over the comparison temperature Tm, and ignition action is taken after the time of t2 (t2<t) seconds from the operation of the electromagnetic pump 2 so that the quantity of the supplied fuel before the ignition becomes small. Accordingly there is no excess rise in the inner pressures in the carburetor and an outer tube 8 by the vaporized gas, and since the fuel goes into a burner 16 with the most appropriate jetting force as soon as a nozzle hole 9a opens, the ignitability is good and there is no fear that tar accumulation in the carburetor 4 and nozzle 9 occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for a combustor that vaporizes and burns liquid fuel such as kerosene.

[Conventional technology]

FIG. 5 is an overall configuration diagram of this type of combustor which is generally widely known.

In the figure, 1 is an oil tank storing liquid fuel such as kerosene, 2 is an electromagnetic pump for supplying the liquid fuel 3 from the oil tank 1 into the vaporizer N4 through the oil pipe 5, and θ is the heater for heating the vaporizer 414. An electric heater, 7 a humidity detector such as a thermistor for detecting the humidity of the vaporizer 4, 8 an outer tube communicating with the vaporizer 4, and 9 a vaporizer! 14 is a nozzle for spouting the vaporized gas of the liquid fuel vaporized in the nozzle hole 9a; 10 is a needle having a needle-like tip for opening and closing the nozzle hole 9a; 11 is integrated with the 21 dollar 10; A movable piece 12 is a solenoid for sliding the movable piece 11, and 13 is a solenoid for sliding the movable piece 11. When the solenoid 12 is not energized, the movable piece 11 is pressed to the left in the figure to block the nozzle hole 9a with the tip of the twenty-one dollar 10. coil spring for, 14 is solenoid 1
When the nozzle hole 9a is opened by energizing 2,
A relief valve integrated with a movable piece 11 for preventing vaporized gas from leaking into the return pipe 15 communicating with the oil tank 1; 1B is a nozzle. a burner disposed opposite the hole 9a; 17 an ignition device for igniting the vaporized gas;
18 is a flame rod for detecting the ionic current of the flame during combustion.

Next, in the combustor having the above configuration, the operation of the conventional example will be explained using the time chart of FIG. 6 and the explanatory diagram of vaporized N humidity of FIG. 7.

When the operation is started, first, the electric heater 6 is turned on if4 to heat the vaporized N4. When the humidity in the vaporizer 4 detected by the humidity detector 7 reaches a predetermined humidity T sufficient to vaporize the preset fuel, the W1 magnetic pump 2 is operated to transfer the liquid fuel 3 to the oil tank 1. From there, the oil is supplied into the vaporizer 4 through the oil feed pipe 5.

The liquid fuel is heated and becomes vaporized gas in the vaporizer 4,
At this time, since solenoid 12 and 11 are on,
The needle 10, which is integrally connected to the movable piece 11, is pushed by the coil spring 13 to close the nozzle hole 9ae, and on the contrary, is slightly opened than the relief valve 141.

The vaporized gas in the vaporizer #4 fills the vaporizer 4 and the outer tube 8, the internal pressure becomes true, and the nozzle hole 9
Since port a is closed, it leaks from the relief valve 14 side through the return pipe 15.

When 8t has passed since the electromagnetic pump 2 started operating, and the internal pressure due to the vaporized gas inside the carburetor 4 and the outer tube 8 has increased to a certain extent, the solenoid 11 is energized and the relief valve 14 is turned on.
At the same time as the nozzle hole 9a is closed, the nozzle hole 9a is opened, and vaporized gas is vigorously ejected from the nozzle hole 9a, drawing in the primary air surrounding Ni and entering the burner 16 as a mixture.

Almost at the same time, the ignition bag M17 placed above the burner 1B is energized to ignite the air-fuel mixture and start combustion. The reason why the pressure of the vaporized gas is increased in advance before it is ejected is to make the air-fuel mixture at the time of ignition to a predetermined concentration, improve ignitability, and perform odorless instant ignition.

By starting the fil, a flame ionic current flows from the flame rod 18 to the burner 16, and after detecting this fil flow, the energization to the ignition device 117 is stopped.

Combustion conditions are constantly monitored by sensing the ionic current of the flame by flame rod 18.

The humidity of the vaporizer 4 during combustion is detected by a humidity detector 7, and is controlled to be a humidity Tb that is slightly higher than that at the time of ignition.

For example, Japanese Patent Publication No. 83-2109 uses two-stage humidity control that makes a difference between humidity control during ignition and humidity control during combustion.
This is because, as shown in Publication No. 1, the ignitability of the air-fuel mixture is better when the humidity at the time of ignition is much lower than the optimum combustion humidity.

Next, when you want to stop combustion, just stop energizing the electromagnetic pump 2 and solenoid 12 and vaporization will begin! ! I! As soon as fuel is no longer supplied into i4, the nozzle hole 9a is closed and the fire is instantly extinguished. After the fire is extinguished, the power supply to the electric heater 6 is also stopped, and the humidity of the vaporized N4 gradually decreases. At this time, when the humidity of the vaporizer 4 is relatively high, for example, when the operation is started again at the time point shown in FIG. Start operation and supply kerosene into the vaporizer M4.

After the electromagnetic pump 2 is operated, the ignition operation starts after a time t has elapsed, and at this time, the humidity inside the vaporizer 4 becomes T,
Since the pressure is much higher than that, the internal pressure inside the vaporized N4 and the outer tube 8 due to the vaporized gas rises too much, and a large amount of vaporized gas is vigorously jetted out at the same time as the nozzle hole 9a opens.

If the vaporized gas flows quickly, it becomes difficult to ignite, and the air-fuel mixture fills the inside and outside of the burner 16 and comes out as mist. If it ignites in this state, it will burn with a large flame for several seconds with a very loud ignition sound, creating a dangerous situation.

In addition, if the internal pressure inside the vaporizer Wi 4 and the outer pipe 8 increases too much due to the vaporized gas, the amount of vaporized gas leaking from the relief valve 14 will also increase, and a large amount of liquid fuel cooled in the return pipe 15 will leak into the oil tank. It will come back within 1. - The liquid fuel exposed to high temperatures becomes easily oxidized, and when it is next vaporized, tar is likely to accumulate inside the vaporizer 4 and nozzle 9.

[Problem to be solved by the invention]

Conventional combustor control devices are configured as described above, so if you restart the operation when the humidity of the vaporized Wi4 is low, the ignition performance will be poor, mist will come out and the back will be deep, or there will be a loud noise when ignited. It is not only dangerous because it burns with a large flame for several seconds with the sound of ignition, but also has problems such as easy accumulation of tar inside the carburetor 4 and nozzle 9.

This invention was made to solve the above-mentioned problems, and even when the vaporizer is operated with a thin wall when the humidity is high, the ignitability is good, and the tar A18 can be used inside the vaporizer or in the nozzle. The purpose of this article is to learn about combustor control devices that are rarely used.

[Means to solve the problem]

The combustor control device according to the present invention is a combustor in which liquid fuel is supplied into a vaporizer by an electromagnetic pump before the ignition starts, and the ignition operation is performed after the liquid fuel is vaporized in advance. The amount of liquid fuel supplied is changed depending on the humidity of the vaporizer.

[Effect]

The combustor control device according to the present invention controls the amount of liquid fuel supplied before the start of ignition so that it increases when the humidity of the vaporizer at that time is low and decreases when it is high.

〔Example〕

An embodiment of the present invention will be described below with reference to the electro-am diagram shown in FIG.

In the figure, 7 is a thermistor as a humidity detector that detects the concentration of vaporized I#4, and the DC voltage V is divided by a resistor 20 connected in series with the A/D conversion circuit 525.
21 converts it into a digital value and inputs it to a microcomputer (hereinafter referred to as microcomputer) 22.

Reference numeral 23 denotes an operation switch for starting or stopping the operation of the combustor, which is similarly connected in series with a resistor 24, and its partial pressure value is input to the microcomputer 22. The microcomputer 22 includes an input circuit 22a, a CPU 22b, a memory 22C, a clock generation circuit 1122d, and an output circuit $226.

Reference numeral 28 denotes an oscillator, which creates a reference time for the microcomputer 22 by being connected to the clock generator 1f#22d.

24.25.2B, 27 is a heater IK1!1'@path which operates in response to an output command from the microcomputer 22, a solenoid drive circuit, an electromagnetic pump drive circuit 9 an ignition device! It is a driving rfR path, and includes an electric heater 6 and a solenoid 12 necessary for combustion. Each serves to operate the electromagnetic bong 122 ignition device [17].

Next, the operation of this embodiment configured as described above will be explained with reference to the control flowchart of FIG. 2.

First, turn on the operation switch 23 (step 30),
When a combustor operation command is given to the microcomputer 22, a signal from the output circuit 22e of the microcomputer 22 is sent to the heater drive circuit 24.
and turns on the electricity overnight (step 31).

The humidity of vaporized N4 is detected by a thermistor 7,
/D conversion circuit 21 to input port $22 of microcomputer 22
8 is input.

The cpty 22b of the microcomputer 22 compares this input value with the preset humidity T in the memory 22c (step 32), and if the set humidity T is higher,
The microcomputer 1 determines that preheating of the vaporizer 4 is completed, and the microcomputer 22
Output circuit 22 Is fp et al. electromagnetic pump drive circuit 2B
The electromagnetic pump 2 is operated to supply liquid fuel into the vaporizer 4 (step 33). At the same time, the CPU 22b of the microcomputer 22 compares the humidity of the vaporizer 4 with the set humidity T and the higher humidity T (step 34).

If you start operation when the humidity of vaporized N4 is at room temperature,
Since the humidity of the vaporizer 4 is not higher than the comparative humidity T1, the ignition operation starts t seconds after the electromagnetic pump 2 starts operating, as in the conventional example (step 35).

On the other hand, if the operation is started before the humidity of the vaporizer 114 decreases after combustion is stopped, the humidity of the vaporizer 114 is equal to or higher than the comparative humidity T1, and in this case, steps 30 to 31, 32, 33, 34. Proceed all at once to 3B, and after electromagnetic pump 2 operates, 1. After seconds (1, < 1
) starts ignition operation. The ignition operation is performed from the output circuit 228 of the microcomputer 22 to the solenoid drive port l1125. A signal is sent to the ignition device M drive 17, turning on the solenoid 12 to open the nozzle hole 9a (step 37), and activating the ignition device 17 (step 38) to ignite the air-fuel mixture.

When the flame rod 18 detects the ionic current of the flame, the microcomputer 22 turns off the ignition device 177G, and combustion begins!
Enter the 11th.

The 1m3 diagram is a time chart showing the operation when the humidity of the vaporizer 1i14 is 73 or higher than the comparative humidity.

1. The time from when the electromagnetic pump 2 is turned on until it starts the ignition operation is shorter than t seconds. , the amount of fuel supplied before ignition starts is reduced.

Therefore, even if the humidity of the vaporizer 4 is much higher than the set humidity T, the internal pressure inside the vaporizer 414 and the outer tube 8 will not rise too much due to the vaporized gas, and the nozzle hole 9a will open and the optimum humidity will be reached. Since the jet power enters the burner 1s, the ignition is as good as when the vaporization temperature is 111 degrees and the humidity is set to T, making a loud ignition sound and the flame getting bigger, and mist leaking out and making it deep. Things like that will no longer be the case.

In addition, since the internal pressure inside the vaporizer Wj4 and the outer pipe 8 does not rise too much, a large amount of vaporized gas does not return to the oil tank 1 side from the relief valve 14, and tar is prevented from forming inside the vaporizer @M4 and the nozzle 9. There is no need to worry about it becoming easy to accumulate.

FIG. 4 shows that the humidity of the vaporizer 4 is comparative humidity 7. This figure shows the relationship between operating time and vaporizer humidity in the above case. The comparative humidity T, is the set humidity T, and 1 during combustion! By setting the control humidity T to a substantially average value, the above effect can be more prominently obtained.

In the above embodiment, the humidity of the vaporizer 54 at the start of operation of the electromagnetic pump 2 is divided into two stages based on one comparison humidity T, and the operating time of the electromagnetic pump 2 before the start of ignition is t seconds p it seconds. However, if the number of stages is increased to three or more, and the operating time of the electromagnetic pump 2 is changed for each stage, the -layer effect will be improved.

In addition, in the above embodiment, the amount of fuel supplied before starting ignition was changed by #controlling the operating time of the electromagnetic pump 2, but the operating time was kept constant and the pumping amount of the electromagnetic pump 2 (per unit time) was changed. Similar effects can be obtained even if the discharge amount is varied.〇 [Effects of the Invention] As described above, according to the present invention, before the start of ignition, liquid fuel is supplied into the carburetor by an electromagnetic pump, In a combustor that performs ignition operation after being vaporized in advance, the amount of liquid fuel supplied before the start of ignition is changed depending on the humidity of the vaporizer, so that the humidity of the vaporizer at the time of starting ignition is Even when the temperature is high, the optimum ignition conditions can be obtained, the ignition noise can be reduced, the mist will not leak and become deep, and the accumulation of tar inside the carburetor and nozzle can be suppressed, improving tar resistance. It has the advantage that it is possible to

[Brief explanation of drawings]

FIG. 1 is an electric circuit diagram showing a combustor control device according to an embodiment of the present invention, and FIG. 2 is a 1111+7 diagram showing its operation.
0-Chart, Figures 3 and 4 are time charts showing the operation of the main parts and an explanatory diagram of vaporized N humidity, and Figure 5 is the M
I! The overall configuration of the sintering machine, Figure 6 is a time chart showing the operation of the conventional example, and Figure 7 is the vaporization N! ! FIG. In the figure, 2 is an electromagnetic pump, 4 is a vaporizer, and 6 is 'N1
1A is a heater, 9 is a nozzle, 1B is a burner, 17 is an ignition snowmaker, and 22 is a microcomputer. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] In connection with the ignition operation of the combustor, the liquid fuel pumped up by the electromagnetic pump is turned into vaporized gas in the vaporizer, and this vaporized gas is ejected from the nozzle and burned in the burner. The combustor is characterized in that the ignition operation is performed after liquid fuel is supplied into the chamber and vaporized in advance, and the amount of liquid fuel supplied before the start of ignition is varied depending on the humidity of the vaporizer. combustor control device.