JPH09229357A - Ignition sequence for hot air heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To completely raise the temperature of an oil feed port of a vaporizer during an ignition and realize a stable ignition without generating an ignition failure or white flame. SOLUTION: A hot air heater comprises a vaporizer for supplying vaporized gas obtained by vaporizing liquid fuel to a burner and burning it, a heating element for vaporizing the liquid fuel, a temperature detecting element for detecting the temperature of the vaporizer, a pump for feeding the liquid fuel to the vaporizer, an igniter for igniting the burner and a control means for controlling the temperature of the vaporizer to a prescribed temperature during a combustion. The control means includes an ignition sequence in which it controls the supply of electric current to the heating element of the vaporizer, retains the control temperature of the vaporizer detected by the temperature detecting element for a prescribed time ▵t at a heat-retaining temperature Th before the control temperature reaches an ignition command temperature Tt lower than a prescribed temperature To during a combustion, and then raises it to the ignition command temperature Tt and operates the igniter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition sequence of a hot air heater such as an oil fan heater equipped with a vaporizing burner.

[0002]

2. Description of the Related Art In an ignition sequence of a conventional warm air heater, as shown in FIG. 3 which is a sectional view of a carburetor of the warm air heater and FIG. 4 which is a temperature characteristic diagram (solid line) of the conventional warm air heater, Liquid fuel is supplied from the port 21 to the vaporization chamber 18 in the vaporizer 13 by a pump, the wick 19 is heated by the heating element 17, and the vaporized gas vaporized on the evaporation surface 25 in the vaporizer is burned via the nozzle 14 through the nozzle 14. To burn and to detect the temperature when burning
Equipped with control means for heating the carburetor temperature to be detected at a predetermined temperature To, and for igniting at a constant temperature Tt at which the preheating temperature of the carburetor 13 is lower than the predetermined temperature To before ignition, ignition is easy. However, there is a type that has been made reliable and the preheating time has been shortened (for example, see Japanese Patent Publication No. 63-21091).

[0003]

However, in the ignition sequence of the conventional warm air heater, the carburetor 13 is connected to the heating element 1.
The temperature of the temperature detector 23 of the carburetor 13 is controlled to a predetermined temperature by the temperature detected by the temperature detection element 24 close to the temperature of the temperature detector 23 of the carburetor 13. The temperature of the oil supply port 21 on the opposite side is as shown in FIG.
As shown in the temperature characteristic diagram (solid line) of the conventional warm air heater, the temperature of the temperature detector 23 is the ignition command temperature Tt at the point A.
Even if it becomes, the temperature of the oil supply port portion 21 on the opposite side has risen only to Tb at the point B, and the oil supply port 20 moves from the oil supply port 20 to the vaporization chamber 1.
The oil that has entered the evaporating surface 25 in 8 cannot be fully evaporated,
The concentration of oil vapor emitted from the burner 2 was low at the initial stage of ignition, and there was a defect that an ignition error occurred or white smoke was emitted.

In particular, when the temperature of the vaporizer 13 is as low as several tens of degrees C or less, the temperature Tb at the point B of the oil feed port portion 21 rises only slightly, and this phenomenon is remarkable.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a burner which burns a mixed gas of vaporized gas obtained by vaporizing liquid fuel and air, and vaporizes the liquid fuel in this burner. A vaporizer for supplying the vaporized gas, a heating element built in the vaporizer for vaporizing the liquid fuel and a temperature detecting element for detecting the temperature of the vaporizer, a pump for feeding the liquid fuel to the vaporizer, and a burner. An igniter for igniting and a control means for controlling the temperature of the carburetor at a predetermined temperature during combustion are provided, liquid fuel is supplied to the carburetor, the temperature of the carburetor is controlled at a predetermined temperature, and the vaporized gas vaporized here is controlled. In the ignition sequence of the warm air heater in which the burner ignites and burns, the control means controls the energization of the heating element of the carburetor, and the control temperature of the carburetor detected by the temperature detection element is lower than the predetermined temperature To during combustion. It was assumed to have a firing sequence to ignite to activate the igniter from raised at retained temperature Th before reaching the fire instruction temperature Tt to the ignition instruction temperature Tt after a predetermined time Delta] t (e.g. ten seconds) thermal insulation.

Further, the control means keeps the temperature Δt at the heat retention temperature Th for a predetermined time only when the control temperature of the carburetor detected by the temperature detecting element is equal to or lower than a predetermined temperature (for example, several tens of degrees C).

[0007]

With the ignition sequence as described above, at the ignition start-up, the carburetor control temperature detected by the temperature detection element is kept warm for a predetermined time (for example, ten and several seconds) at the heat retention temperature before reaching the ignition command temperature. By doing so, the temperature of the oil supply port at the time of raising the temperature to the ignition command temperature is raised to a temperature at which the oil that has entered the evaporation surface in the carburetor from the oil supply port is sufficiently evaporated, and the igniter is activated to ignite. When it is turned on, it has the function of providing stable ignition without misfiring or emitting white smoke.

Further, this ignition sequence is performed only when the temperature of the carburetor at the time of ignition is lower than a predetermined temperature (for example, several tens of degrees C) at which ignition is likely to occur or white smoke is emitted (for example, several tens of degrees C) for a predetermined time (for example, By keeping it warm for more than 10 seconds, when the carburetor temperature is high and stable ignition is possible without misfire or white smoke emission, it acts to ignite without taking longer than necessary.

[0009]

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

FIG. 1 is a sectional view showing a hot air heater according to an embodiment of the present invention, and FIG. 2 is a burner of the hot air heater.
FIG. 3 is an explanatory diagram of a control and oil feeding path including a carburetor, and FIG.
FIG. 4 is a cross-sectional view of a carburetor common to the hot air heater and the conventional hot air heater, and FIG. 4 is a temperature characteristic diagram of each of the hot air heaters.

In the figure, reference numeral 1 is a main body of a warm air heater. Reference numeral 2 denotes a burner provided in the main body 1. The burner 2 has a primary air hole 3 at one end and a flame hole 4 at the upper portion. An igniter 29 has a discharge electrode disposed near the flame hole 4. Reference numeral 5 denotes a burner base provided below the inside of the main body 1. The burner base 5 is provided with a burner 2, and secondary air holes 6 are provided on the front and rear sides of the burner 2.

An air chamber 7 containing the burner 2 is provided upstream (downward) of the burner base 5, and a combustion chamber 8 is provided downstream (upper) of the burner base 5.
A flame 9 is formed in the flame hole 4 in the combustion chamber 8. Behind the combustion chamber 8, there is provided a blower 10 whose rotation speed is variable,
Further, a secondary air opening 11 is opened in the rear of the combustion chamber 8, and a plurality of secondary air openings 11 are provided at the height of the middle portion of the combustion chamber 8. A secondary air inlet 12 is also provided on the side surface of the combustion chamber 8 from the middle portion to the upper portion thereof.

Reference numeral 13 is a vaporizer having a nozzle 14,
It is opposite the burner 2. Reference numeral 15 denotes a pump whose oil amount is variable. One end of the pump 15 is connected to the carburetor 13 and the other end thereof is connected to the fuel tank 30.

The carburetor 13 is closed at one end by a lid 16,
A heating element 17 is inserted and fixed from the other end to form a vaporization chamber 18. A nozzle 14 that communicates with the temperature detecting element 24 formed of a thermistor and the vaporization chamber 18 is disposed on the heating element 17 fixed side of the vaporizer 13. On the other hand, on the other end side of the carburetor 13, an oil feed port 20 to which a pump 15 for supplying fuel is connected is provided. A wick (filler) 19 that promotes the diffusion and vaporization of oil is provided on the evaporation surface 25 in the vaporization chamber 18. Reference numeral 26 is a heat recovery rod for recovering heat from the burner 2.

Reference numeral 27 is a cleaning rod of the nozzle 14, and 28 is a solenoid for driving the cleaning rod 27. 31 receives the temperature detection of the thermistor 24, operates the blower 10, the heating element 17, the pump 15, the solenoid 28, and the igniter 29, controls the temperature of the carburetor 13 to a predetermined temperature, and ignites in accordance with the ignition sequence. It is a control means for controlling the entire warm air heater.

The operation of this embodiment having the above structure will be described below.

When the warm air heater is turned on, the vaporizer 13
When the vaporizer 13 reaches the vaporization temperature, the pump 15 is electrified. The fuel supplied from the pump 15 is vaporized by the vaporizer 13, and the vaporized gas is ejected from the nozzle 14 into the burner 2. At this time, the jetting force from the nozzle 14 sucks the surrounding air from the primary air hole 3, and at the same time, a part of the air from the blower 10 is also pushed in from the primary air hole 3 as combustion air. The vaporized gas and the primary air are mixed by a mixing pipe (not shown) in the burner 2 and jetted from the flame hole 4 at the burner outlet to form a flame 9 in the combustion chamber 8.

Here, the temperature control of the carburetor 13 by the control means 31 is performed according to an ignition sequence when a driving operation is performed.
When the heating element 17 of the carburetor 13 is energized, its temperature rise is detected by the thermistor 24, and as shown by the dotted line in FIG. 4, when it reaches the first heat retention temperature Th that is lower than the ignition command temperature Tt, a predetermined time Δt (for example, 10 When a predetermined time Δt has passed, the temperature of the oil supply port 20 becomes the temperature Tb ′ at which the oil can be sufficiently evaporated when the temperature reaches the point A ′ at which the ignition command temperature Tt is reached. At the point B ′, the pump 15 is operated to send the fuel from the oil feed port 20 to the vaporization chamber 18, and is vaporized at the evaporation surface 25 in the vaporization chamber 18 via the wick 19, and then the nozzle 14 to the inside of the burner 2. And is ignited by the igniter 29 on the upper surface of the flame hole 4, and stable ignition can be performed without misfiring or emission of white smoke.

Thereafter, the control temperature of the carburetor 13 detected by the thermistor 24 is T higher than the ignition command temperature Tt.
It is controlled to be constant at o.

During this operation, the cleaning rod 27 of the nozzle 14 is controlled by the solenoid 28 so as to be opened and closed when the operation is stopped.

The control means 31 keeps the temperature only when the temperature of the carburetor 13 at the time of ignition detected by the temperature detection element 24 is below a predetermined temperature (for example, several tens of degrees C) at which ignition of white smoke is likely to occur. Assuming that the temperature Th is maintained for a predetermined time Δt (for example, ten or more seconds), if the temperature of the carburetor is high and stable ignition is possible without misfiring or white smoke emission, ignition is performed without taking an excessively long heat retention time. it can.

[0022]

As described above, according to the present invention, the control means controls the energization of the heating element of the carburetor and before the control temperature of the carburetor detected by the temperature detecting element reaches the ignition command temperature lower than the predetermined temperature during combustion. Since it has an ignition sequence in which the ignition command temperature is raised after the temperature is maintained for a predetermined time after the temperature is maintained, the temperature of the oil supply port is set to a temperature at which the oil can be sufficiently evaporated at the time of ignition. It is possible to provide an ignition sequence of a warm air heater which is capable of performing stable ignition without raising an erroneous ignition or emitting white smoke.

Further, since the control means keeps the carburetor at a controlled temperature for a predetermined time only when the control temperature of the carburetor detected by the temperature detecting element is equal to or lower than the predetermined temperature, the carburetor has a high temperature and an ignition error or white When stable ignition without smoke emission is possible, there is an effect that ignition can be performed without taking an excessive heat retention time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a combustion device of a warm air heater according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a control and oil feeding path including a burner and a carburetor of the hot air heater.

FIG. 3 is a cross-sectional view of a carburetor common to the hot air heater and a conventional hot air heater.

FIG. 4 is a temperature characteristic diagram of a warm air heater according to an embodiment of the present invention and a conventional warm air heater.

[Explanation of symbols]

 13 vaporizer 17 heating element 24 temperature detecting element 29 igniter 31 control means

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Isao Watanabe 3-3 Shinjuyoji, Kashiwa-shi, Chiba Prefecture 1 Hitate Co., Ltd. Hometec (72) Masaharu Aramaki 1 3-2 Shinjuyoji, Kashiwa-shi, Chiba 1 Hitsuritsu Co., Ltd. In Home Tech

Claims (2)

[Claims] 1. A burner for burning a mixed gas of vaporized gas obtained by vaporizing a liquid fuel and air, a vaporizer for supplying the vaporized gas obtained by vaporizing the liquid fuel to the burner, and a vaporizer for vaporizing the liquid fuel contained in the vaporizer. A temperature detecting element for detecting the temperature of the heating element and the vaporizer, a pump for feeding the liquid fuel to the vaporizer, an igniter for igniting the burner, and a control means for controlling the temperature of the vaporizer at a predetermined temperature during combustion. With and
In the ignition sequence of the warm air heater, in which the liquid fuel is supplied to the carburetor, the temperature of the carburetor is controlled to a predetermined temperature, and the vaporized gas vaporized here is ignited and burned by the burner, the control means (31) is characterized by the vaporizer. Vaporizer (1) which controls energization of the heating element (17) of (13) and is detected by the temperature detecting element (24)
The control temperature in 3) is a predetermined time Δt at the heat retention temperature Th before reaching the ignition command temperature Tt lower than the predetermined temperature To during combustion.
An ignition sequence of a warm air heater, characterized in that after the temperature is maintained, the temperature is raised to an ignition command temperature Tt and then an igniter (29) is operated to ignite. 2. The control means (31) keeps the temperature Δt at the heat retention temperature Th for a predetermined time only when the control temperature of the vaporizer (13) detected by the temperature detection element (24) is equal to or lower than a predetermined temperature. The ignition sequence of the warm air heater according to claim 1.