JPH07107446B2 - Liquid fuel vaporization combustor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vaporization combustor that vaporizes and burns a liquid fuel such as kerosene, and particularly relates to prevention of tar content in the vaporization section.

2. Description of the Related Art Conventionally, a vaporization type combustor of this type is often used in an indoor heater such as an oil fan heater. For example, liquid fuel sent by a fuel pump 1 is fed by a heater 2 as shown in FIG. It is configured to be mixed with the air supplied by the fan 4 which is vaporized by the vaporizer 3 to be heated and burned by the burner 5. Here, the vaporizer 3 detects the temperature by the vaporization temperature sensor 6 and is controlled to a constant temperature by a heater controller (not shown). In this method, when the burner 5 is burned for a long time, or when bad kerosene is burned, tar, which is a high boiling point component of kerosene, adheres to the surface of the vaporization part such as the vaporization wall, and the vaporization performance deteriorates. Combustion may be impossible. In order to solve this, the means described in Japanese Utility Model Laid-Open No. 59-55226 has been proposed. As shown in FIG. 3, the internal vaporization wall 3a of the vaporizer 3 is surface-treated with a self-cleaning coating 7 having a self-cleaning effect, such as manganese dioxide or aluminosilicate. With this configuration, when liquid fuel receives vaporization heat on the vaporization wall 3a of the vaporizer 3 and becomes vaporized gas, residues such as high-boiling components in the fuel adhere in tar form, but manganese dioxide and aluminosilicate of the self-cleaning coating 7 The tar is oxidized and decomposed into water and carbon dioxide in order to increase the oxidation rate by a catalyst such as.

Problems to be Solved by the Invention In the above-described conventional configuration, two factors are required: a certain temperature or higher to obtain the contact effect, and a certain period of time to oxidize by the catalyst. is necessary.
However, in the configuration shown in FIG. 3, the carburetor 3 is maintained at a constant temperature by heating by the heater 2 or heat conduction of the burner 5 while the burner 5 is burning, but when the combustion of the burner 5 is stopped, The remaining fuel adheres to the inner wall 3a of the vaporization chamber and the heating of the vaporizer 3 is also stopped at this time, so the temperature and time for the self-cleaning coating 7 to obtain the catalytic effect are not satisfied. Therefore, it adheres to the vaporization chamber wall as tar. By repeating the operation and stop of the combustor, the above-mentioned tar content is accumulated, which causes a problem that vaporization performance is deteriorated. In order to solve this, a method of heating the carburetor 3 to a certain temperature or higher by the heater 2 at the initial stage of operation to oxidize tar and then supplying fuel by the pump 1 is possible, but in this case, combustion of the burner 5 is started. It was difficult to realize it with a heater that requires a long waiting time.

Means for Solving the Problems In order to solve such conventional problems, a liquid fuel vaporization combustor of the present invention comprises a vaporizer for vaporizing the liquid fuel by energizing a heater and a burner for burning the vaporized fuel. Includes a combustor that includes the burner, a vaporization temperature control unit that controls the combustion of the burner and controls the energization to the heater by the signal of the vaporization temperature sensor that detects the temperature of the vaporizer, and an operation switch that instructs the start / stop of the combustor. In addition to having a control, the vaporization part of the vaporizer is subjected to a surface treatment having a cleaning effect, and the vaporization temperature control part has a warming circuit part for driving and controlling the heater even when the combustor is stopped by the operation switch. It is configured.

Effect of the Invention The present invention is a catalyst for self-cleaning coating even if the fuel remaining in the vaporizer adheres to the vaporization chamber wall as tar because the vaporizer is preheated even when the operation switch is off due to the above-described configuration. It has the effect that it is oxidized by the action, and the cleaning is completed by the start of the next combustion.

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

FIG. 1 is a block diagram of an embodiment of the liquid fuel vaporization combustor 8 of the present invention. FIG. 1 is an example of a heater, and parts having the same operation as in FIG. 3 are given the same numbers. Liquid fuel stored in a fuel tank (not shown) is supplied to the carburetor 3 by the fuel pump 1 through the fuel pipe 9. The vaporizer 3 is heated by the heater 2 to vaporize the fuel. Vaporizer 3
Has been given a self-cleaning coating 7. The vaporized fuel is mixed with the combustion air supplied by the blower motor 4, ignited by an igniter (not shown), and burned by the burner 5.

The controller 10 drives and controls the fuel pump 1, the vaporization heater 2, and the blower motor 4. In the fuel pump 1 and the blower motor 4, the combustion control unit 11 controls the fuel supply amount and the combustion air amount so that the temperature of the room becomes constant. On the other hand, the heater 2 is controlled by the vaporization temperature control unit 12 so that the temperature of the vaporizer 3 detected by the vaporization temperature sensor 6 is maintained at a preset temperature.

Reference numeral 13 is an operation switch for instructing the operation of the combustion 8. When the operation switch 13 is turned on, the combustor 8 operates and the burner 5 starts combustion. Here, the warming circuit 14 operates when the operation switch 13 is turned off, and only the vaporization temperature control unit 12 continues to operate. At this time, the temperature setting of the vaporizer 3 may be switched to the lowest temperature at which the self-cleaning coating 7 can catalyze.

Reference numeral 15 is a tire that determines the operating time of the warming circuit unit 14, and keeps the vaporizer 3 heated by the heater 2 for a time (for example, 3 hours) required for the self-cleaning coating 7 to oxidize tar by catalytic action.

FIG. 2 shows a specific circuit diagram of the main part of the present invention. The same parts as those in FIG. 1 are given the same numbers. Reference numeral 16 is a DC power supply circuit, which includes a combustion control unit 11, a warming circuit unit 14, and a vaporization temperature control unit 12.
And so on. The combustion control unit 11 has an operation switch 13
Is connected to ON (a contact), the burner 5 in FIG.
The fuel pump 1 and the blower motor 4 are driven and controlled to burn the fuel. At the same time, the temperature setting signal c of the vaporizer 3 is output to the vaporization temperature control unit 12.

The vaporization temperature control unit 12 compares the set temperature signal c from the combustion control unit 11 and the signal d of the vaporization temperature sensor 6 with the comparator 17, and outputs a signal to the transistor 18. Here, the comparator 17 uses a generally known operational amplifier (OP amplifier). now,
When the temperature of the vaporization temperature sensor 6 is lower than the set temperature, the potential c <d and the output potential e becomes high. This turns on the transistor 18 and drives the relay 19. Relay 19
The contact 20 is connected to the power source 20 in series with the vaporization heater 2 of the vaporizer 3, and when the relay 19 is turned on, the contact 20 conducts to supply electric power to the heater 2. When the temperature of the vaporization temperature sensor 6 rises and becomes higher than the set temperature, the transistor 18 is turned off, so that the power supply to the heater 2 is stopped. In addition to this, the heater may be controlled by stepless power control.

The above operation is the same as the operation of the conventional combustor, and when the operation switch 13 is turned off here, the combustion control unit 11 stops the combustion of the burner 5. At this time, the vaporization temperature set value c is designed to be high (equivalent to the + potential of the power supply).
At the same time, the contact point of the operation switch 13 is also switched to b, and the temperature setting value of the carburetor becomes a value f divided by the resistors 21 and 22 of the warming circuit section 14, and thereafter the vaporization temperature control section 12 determines this temperature and the vaporization temperature. The temperature of the sensor 6 is compared and the heater 2 is driven. The diodes 23 and 24 form an OR circuit, and the set temperature of the carburetor is set to c depending on whether the operation switch 13 is on or off.
And f.

When the warming circuit section 14 operates, the timer 15 starts counting time, and when a predetermined time elapses, the contact 25
open. When the contact 25 is turned off, the electric potential f is kept high, and therefore the electric potential d> f does not hold and the heater 2 is not energized no matter how much the temperature of the vaporization temperature sensor 6 decreases. That is, when the timer 15 has passed a predetermined time, the operation of the warming circuit unit 14 is stopped, the power supply to the heater 2 is stopped, and the power consumption is reduced. The timer 15 turns on the operation switch 13 during the time counting. It will be initialized if turned on.

The display 26 uses an issuing diode (LED) here, the operation switch 16 is off, and the warming circuit 14 is used.
Illuminates during operation of to indicate that the heater is energized.

The setting time of the timer 15 may be set to a time sufficient for the self-cleaning coating 7 to oxidize tar by catalytic action, for example, 3 hours, but by setting this time to 24 hours, the combustor is set to When used, the carburetor 3 can be maintained in a preheated state. Also timer
Instead of 15, the means switch is used to turn 25 on and off, and it is easy to clean when the user deems it necessary.

In the examples, the self-cleaning coating is described by using manganese dioxide or aluminosilicic acid as an example. However, other materials may be used for the same effect, or enamel or other surface treatment.

EFFECTS OF THE INVENTION As described above, the liquid fuel vaporization type combustor of the present invention has the following effects.

(1) Even if the combustor is not operating after the operation switch is turned off, the carburetor heater is preheated by the warming circuit section, so the tar adhering due to the residual fuel after the fuel pump is stopped is self-cleaning. It is sufficiently oxidized by the catalytic action of the coating, and even if a bad fuel is used, the capacity of the vaporizer is not deteriorated.

(2) Since the carburetor is always preheated while the warming circuit is operating, if the operation switch is turned on, the time required for the carburetor to reach the temperature at which fuel can be vaporized is short, and after the operation switch is turned on. It is very convenient and easy to use because the burner is ignited quickly, the ignition waiting time is almost eliminated, and when it is applied to heating equipment, it becomes warm quickly.

[Brief description of drawings]

FIG. 1 is a block diagram for explaining the configuration and control operation of a liquid fuel vaporization type combustor according to an embodiment of the present invention, FIG. 2 is a circuit diagram showing a concrete circuit example of a main part of the controller, and FIG. It is a block diagram of the combustor of a prior art example. 2 ... Heater, 3 ... Vaporizer, 5 ... Burner, 6 ... Vaporization temperature sensor, 7 ... Self-cleaning coating, (Surface treatment with cleaning effect), 8 ... Combustor, 10 ...
... Controller, 12 ... Vaporization temperature control section, 13 ... Operation switch, 14 ... Warming circuit section, 15 ... Timer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuhiko Yamamoto 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Katsuzo Kogawa, 1006 Kadoma, Kadoma City Osaka Prefecture 72) Inventor Yasushi Hirata No. 1006, Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-55-92817 (JP, A) JP-A-61-140721 (JP, A) JP-A-SHO 61-243218 (JP, A) Actually opened 61-128520 (JP, U)

Claims (2)

[Claims] 1. A vaporizer for vaporizing liquid fuel by energizing a heater, and a combustor including a burner for burning vaporized fuel,
A controller including a vaporization temperature control unit that controls the combustion of the burner and a signal of the vaporization temperature sensor that detects the temperature of the vaporizer to control energization to the heater, and a controller that includes an operation switch that instructs operation / stop of the combustor. Liquid fuel vaporization that has a warming circuit section that performs a surface treatment having a cleaning effect on the vaporization section of the vaporizer and that drives and controls the heater even when the operation is stopped by the operation switch in the vaporization temperature control section. Type combustor. 2. The liquid fuel vaporization type combustor according to claim 1, wherein the warming circuit section has a timer which stops its operation after a lapse of a certain time after the operation switch is turned off.