JPH10300026A - Vaporizing combustion apparatus for liquid fuel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vaporizing combustion apparatus which enables the control of the temperature of a vaporizer during the combustion with a simpler and more inexpensive mechanism. SOLUTION: A heat receiving device 23 for receiving heat from a burner is made separable from a vaporizer 21 and the both are linked by a link part. The link part herein used is a bimetal 40. The bimetal 40 is bent projecting to the left so that the heat receiving device 23 is separated from the vaporizer 21 when the temperature is high while it is bent projecting to the right so that the heat receiving device 23 gets tight onto the vaporizer 21 when the temperature is high. This enables properly interrupting of heat conduction to the vaporizer 21 from the heat receiving device 23 thereby automatically holding the temperature of the vaporizer 21 within a specified range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel vaporization apparatus (hereinafter referred to as "vaporization combustion apparatus") which vaporizes liquid fuel such as kerosene to produce gaseous fuel and burns the gaseous fuel.

[0002]

2. Description of the Related Art A general vaporizing and burning apparatus is provided with a vaporizer which is heated by a heating means such as a heater or a burner. When the vaporizer is heated and liquid fuel is supplied thereto, the liquid fuel is vaporized to generate gaseous fuel. Then, heat is generated by burning this gaseous fuel in the main burner.

When a burner is used as the heating means,
Usually, a heat receiving section provided with fins or the like is provided in a vaporizer, and the vaporizer is heated by a burner. As this burner, a special burner (pilot burner) may be provided in particular, or a pilot burner is not provided, and a part of heat generated by the main burner is used to heat the heat receiving section. Sometimes. However, when using the heat from the main burner, since the heat cannot be used before the main burner is ignited, the vaporizer is also provided with another heating means such as a heater,
When the apparatus is started, it is necessary to heat the vaporizer by this additional heating means.

When heating a vaporizer, it is necessary to control its temperature appropriately. This is for the following reasons. For example, in a case where the liquid fuel is vaporized by a vaporizer that vaporizes the liquid fuel by dropping the liquid fuel on the high-temperature vaporized surface, if the temperature of the vaporized surface is too low compared to the vaporization temperature of the liquid fuel, one of If the temperature of the vaporized surface is too high, the liquid fuel will cause film boiling on the vaporized surface while the liquid fuel in the portion will not be vaporized. In such a case, heat transfer from the vaporizing surface to the liquid fuel becomes insufficient, so that appropriate vaporization cannot be performed. To prevent this from happening,
It is necessary to control the temperature of the vaporizer.

[0005] The method of controlling the temperature of the vaporizer differs depending on the method of heating the vaporizer. For example, when heating a carburetor by both a heater and a main burner, if the amount of heat from the main burner is excessive compared to the amount of heat required to vaporize the liquid fuel, appropriate temperature control of the carburetor should be performed. Can not be done. For this reason, for example, by devising the shape and size of the fins of the heat receiving portion, the amount of heat supplied from the main burner to the vaporizer is appropriately suppressed, and the liquid fuel is not vaporized only by the heat from the main burner alone. The heater is used to compensate for the insufficient amount of heat.

[0006] When the vaporizer is heated by the pilot burner, for example, the pilot burner is appropriately turned on / off in accordance with the temperature of the vaporizer, or the combustion amount of the pilot burner is continuously changed as appropriate. The amount of heat received by the heat receiving section from the pilot burner is changed.

[0007]

As described above, the conventional evaporative combustion apparatus uses a method of controlling the temperature of the evaporator by controlling the amount of heat generated by the heating means in accordance with the temperature of the evaporator. However, in such a method, a complicated control system including a temperature detector including a thermistor for detecting the temperature of the vaporizer and a temperature control circuit including a microcomputer is indispensable. This is one of the reasons for increasing the manufacturing cost of the evaporative combustion apparatus.

Further, when a heater is included in the heating means, it is necessary to supplement the heat with the heater even during combustion depending on the amount of combustion, the temperature, and the like, so that there is a problem that the running cost increases.

The present invention has been made to solve such a problem, and an object of the present invention is to control the temperature of a vaporizer by a simpler and cheaper mechanism than in the past. It is to provide a vaporization combustion device.

[0010]

According to a first aspect of the present invention, there is provided a vaporization / combustion apparatus for vaporizing a liquid fuel, and receiving the heat from a heat source to generate the heat. A heat receiving portion for conducting to the vaporizing portion, wherein the heat receiving portion is separable from the vaporizing portion, and the heat receiving portion is separated from the vaporizing portion when the temperature of the vaporizing portion exceeds a first predetermined temperature. Cutting a heat conduction path from the heat receiving section to the vaporizing section, and when the temperature of the vaporizing section falls below the first predetermined temperature or a second predetermined temperature lower than the first predetermined temperature, the vaporization is performed. A heat conduction control means for forming a heat conduction path from the heat receiving section to the vaporizing section by bringing the heat receiving section into contact with the section.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A vaporizing combustion apparatus according to the present invention is configured such that a heat receiving section for receiving heat from a heat source such as a burner and conducting the heat to a vaporizing section can be separated from the vaporizing section. By appropriately cutting off the heat conduction path from the heat receiving section to the vaporizing section according to the height, the temperature of the vaporizing section is stabilized at the first temperature or maintained between the first temperature and the second temperature. Temperature control, such as

In the evaporative combustion apparatus according to the present invention as described above, since the temperature of the evaporator can be controlled even when the heat value of the heat source is kept constant, a temperature detector and a temperature control circuit are indispensable. It is possible to construct a temperature control system having a configuration different from that of a conventional complicated temperature control system.

The heat conduction control means includes a temperature sensing element whose shape or size changes in accordance with the temperature of the vaporizing section, and the heat receiving section with respect to the vaporizing section by the shape or dimension change of the temperature sensing element. By changing the relative position, it is possible to adopt a configuration in which a heat conduction path from the heat receiving section to the vaporizing section is cut off. That is, by moving the heat receiving unit using a force that changes the shape or size of the thermosensitive body according to the temperature as a power source, the heat receiving unit is brought into contact with the vaporizing unit or separated from the vaporizing unit. In this case, the temperature of the vaporizer can be controlled without using a temperature detector or a temperature control circuit. The temperature sensing element is, for example, a bimetal.

The first and second predetermined temperatures are determined within a temperature range in which the liquid fuel can be appropriately vaporized.
For example, kerosene (boiling point 180-270 ° C) as liquid fuel
When a vaporizing section is used as the vaporizing section to vaporize the liquid fuel by dropping the liquid fuel on the heated vaporizing surface, the first predetermined temperature is about 300 ° C., and the second When the predetermined temperature is about 220 ° C., it is possible to prevent the liquid fuel from causing film boiling on the vaporized surface, and to apply sufficient heat to the liquid fuel from the vaporized surface to vaporize all the liquid fuel. it can.

[0015]

As described above, in the evaporative combustion apparatus according to the present invention, the structure of the control system for controlling the temperature of the evaporator during combustion can be simplified, and the production cost of the apparatus can be reduced. can do. Furthermore, since it is not necessary to use a heater for controlling the temperature during combustion, the running cost can be reduced.

[0016]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of a vaporization combustion apparatus according to the present invention. In this evaporative combustion apparatus, the end of the liquid feed pipe 12 is immersed in the liquid fuel 11 stored in the fuel tank 10. A liquid supply pump 13 is provided in the middle of the liquid supply pipe 12. The nozzle 14 provided at the tip of the liquid feed pipe 12 faces the vaporizing surface 22 of the vaporizer 21. The vaporizing surface 22 faces a ventilation passage 32 connecting the ventilation mechanism 30 and the mixing chamber 31. Immediately above the mixing chamber 31, a burner head 3 having a large number of air-fuel mixture jets 33
4 are provided. An igniter 35 is provided on the upper surface of the burner head 34.

The structure of the vaporizing section provided in the vaporizing combustion apparatus of this embodiment will be described with reference to FIG. The vaporizing section includes a vaporizer 21 having the vaporizing surface 22, a heat receiver 23 disposed adjacent to the burner head 34, and the vaporizer 21 and the heat receiver 23.
And a pair of upper and lower connecting parts 24a and 24b (hereinafter, both are collectively referred to simply as "connecting parts 24"). The vaporizer 21 has a heat transfer surface 25 provided on the side closer to the heat receiver 23 in addition to the vaporization surface 22. The heater 26 and the thermistor 2 are provided inside the vaporizer 21.
7 are provided. The heat receiver 23 has a large number of fins 29 arranged on a heat receiving substrate 28, and the vaporizer 2 of the heat receiving substrate 28 is provided.
The surface close to 1 is formed so as to match the heat transfer surface 25. The connection component 24 includes a temperature-sensitive component 40 made of a component (such as a bimetal) whose shape changes according to the temperature,
A heat insulating part 41 made of a heat insulating material such as a heat insulating ceramic is rotatably connected. These two parts 40, 41
Among them, one end of the temperature-sensitive component 40 is fixed to the vaporizer 21, and one end of the heat-insulating component 41 is fixed to the heat receiver 23.

The operation of the evaporative combustion apparatus having the above configuration is as follows. First, when the heater 26 is energized at the start-up of the apparatus, the heat generated by the heater 26 causes the vaporizer 21 to emit heat.
Temperature rises. When the temperature of the vaporizer 21 detected by the thermistor 27 reaches the vaporization temperature of the liquid fuel 11 (for example, about 250 ° C. when kerosene is used as the liquid fuel), the liquid feed pump 13 is started. Then, the liquid fuel 11 stored in the fuel tank 10 is sucked into the liquid sending pipe 12 and is jetted from the nozzle 14 to the vaporizing surface 22. At this time, since the temperature of the vaporizing surface 22 is higher than the vaporizing temperature of the liquid fuel 11, the liquid fuel 11 jetted to the vaporizing surface 22 instantaneously vaporizes by obtaining heat from the vaporizing surface 22. The gaseous fuel thus generated diffuses into the air passage 32, and the air
From 0, the air flows into the mixing chamber 31 together with the air supplied to the air passage 32. In the mixing chamber 31, the gaseous fuel and the air are mixed to generate an air-fuel mixture. The air-fuel mixture is ejected from an air-fuel mixture outlet 33 provided in the burner head 34 to the upper surface of the burner head 34. When the igniter 35 ignites the air-fuel mixture thus ejected, the air-fuel mixture starts burning and a flame is generated.

The operation of the vaporizing section during combustion will be described with reference to FIG. In the following description, the temperature-sensitive component 4
It is assumed that a bimetal (hereinafter, referred to as a bimetal 40) that bends rightward on the drawing at a low temperature and protrudes leftward at a high temperature is set to 0.

First, immediately before the start of combustion, the vaporizing section
It is assumed that the heat receiving substrate 28 of the heat receiver 23 is in close contact with the heat transfer surface 25 of the vaporizer 21 as shown in FIG.

When the combustion is started, the temperature of the heat receiver 23 becomes high due to the radiant heat from the flame on the burner head 34 and the heat transfer from the exhaust gas, and the heat is transmitted from the heat receiver 23 to the vaporizer 21. Become like As a result, the temperature of the vaporizer 21 increases, and the temperature of the bimetal 40 increases accordingly. Due to this temperature rise, a force for bending the bimetal 40 so as to project to the left is generated. Then, when the temperature of the vaporizer 21 (that is, the temperature of the bimetal 40) reaches a certain temperature (first temperature), the direction of the warping of the bimetal 40 is reversed. Since one end of the bimetal 40 is fixed to the vaporizer, when the direction of the warp is reversed, the shape of the bimetal 40 is bent rightward as shown in FIG. In this case, the heat receiver 23 is separated from the vaporizer 21.

When the heat receiver 23 is separated from the vaporizer, the liquid fuel removes heat from the vaporization surface 22 when the liquid fuel vaporizes, while the heat conduction from the heat receiver 23 to the vaporizer 21 is lost. The temperature of 21 decreases as the vaporization proceeds. Along with this, the temperature of the bimetal 40 fixed to the vaporizer 21 also decreases, and a force is generated to bend the bimetal 40 so as to project to the right. When the temperature of the vaporizer 21 (that is, the temperature of the bimetal 40) reaches a certain temperature (second temperature), the direction of the warp of the bimetal 40 reverses, and as shown in FIG. And the heat receiving substrate 28 of the heat receiver 23 is
1 is in close contact with the heat transfer surface 25. Thereby, the heat receiver 2
The heat conduction from 3 to the vaporizer 21 occurs, and the temperature of the vaporizer 21 starts to rise.

As described above, in the vaporizer of the present embodiment, the state in which the heat receiver 23 is in close contact with the vaporizer 21 and the state in which the heat receiver 23 is separated from the vaporizer 21 are automatically repeated. The temperature always falls between the first temperature and the second temperature. In such temperature control during combustion,
The operation is performed without using the heater 26 and the thermistor 27, and there is no need for a control device using a microcomputer or the like.

The first temperature and the second temperature are determined by the type of the material constituting the bimetal, the length of the bimetal, the distance from the position where the bimetal is joined to the heat insulating component to the vaporizer, and the like. Therefore, by appropriately setting these conditions, the first temperature and the second temperature can be set to desired values. When kerosene is used as the liquid fuel, the first temperature and the second temperature are each 3
When the temperature is set to about 00 ° C. and about 220 ° C., kerosene can be appropriately vaporized.

FIG. 3 is a diagram showing a schematic configuration of another embodiment of the vaporization and combustion apparatus according to the present invention. Hereinafter, the configuration and operation of the vaporization combustion device will be described. Note that, of the components of the vaporization combustion device of FIG. 2, components that are structurally and functionally the same as those described above with reference to FIG. 1 are denoted by the same reference numerals as those used in FIG. Description is omitted.

The vaporizing section provided in the vaporizing and burning apparatus of this embodiment also has a carburetor 51 having a vaporizing surface 52 and a heat transfer surface 55 and a fin 59 on a heat receiving substrate 58, similarly to the vaporizing section of the apparatus of FIG. And a connecting part 54a formed by rotatably connecting the temperature-sensitive part 60 and the heat-insulating part 61 to each other.
And 54b. The vaporizing surface 52 of the vaporizer 51 is connected to the vaporizing chamber 3 provided on the way of the ventilation passage 32.
6 inside. The tip of the liquid supply pipe 12 is
And faces the vaporizing surface 52. Note that a nozzle is not provided at the tip of the liquid sending pipe 12. Further, the evaporative combustion apparatus of this embodiment is provided with a pilot burner 37, and the heat receiver 53 is arranged at a position where it receives heat from the pilot burner 37.

In the vaporizing combustion apparatus of this embodiment, when the liquid fuel 11 is dropped from the tip of the liquid feed pipe 12 onto the vaporizing surface 52 while the vaporizing surface 52 of the vaporizer 51 is heated, the liquid fuel 11 is vaporized. Takes heat from 52 and evaporates. The gaseous fuel thus obtained is diffused into the vaporization chamber 36 and is supplied to the air passage 3
2 and the mixing chamber 3 together with the air supplied into the vaporizing chamber 36.
1 where an air-fuel mixture is produced. Then, the air-fuel mixture is ejected to the upper surface of the burner head 34 through the air-fuel mixture ejection port 33, and is ignited by the igniter 35 to burn.

The temperature control of the vaporizer 51 during the combustion of the air-fuel mixture is performed in the same manner as in the apparatus shown in FIG. That is, a temperature-sensitive component (bimetal) according to the temperature of the vaporizer 51
Since the direction of the warp of 60 is reversed, the pilot burner 3
The state where the heat receiver 53 heated by 7 is in close contact with the vaporizer 51 and the state where it is separated from the vaporizer 51 are repeated, whereby the temperature of the vaporizer 51 always falls between the first temperature and the second temperature. It is.

Although the embodiments of the vaporization and combustion apparatus according to the present invention have been described above, these are merely examples, and it goes without saying that various modifications can be made within the spirit and scope of the present invention. For example, in the above embodiment, the temperature-sensitive component 40 is formed using a bimetal, but the temperature-sensitive component 4 is formed using a material having a large coefficient of thermal expansion (for example, a magnesium alloy or a zinc alloy).
0, and the distance between the vaporizer 21 (or 51) and the heat receiver 23 (or 53) is adjusted by using the fact that the size (length) of the temperature-sensitive component 40 changes according to the temperature. You can also do so.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of an embodiment of a vaporization combustion apparatus according to the present invention.

FIG. 2 is a diagram for explaining the operation of a vaporization unit during combustion.

FIG. 3 is a diagram showing a schematic configuration of another embodiment of the vaporization combustion device according to the present invention.

[Description of Signs] 21, 51: Vaporizers 23, 53 ... Heat receivers 24, 54 ... Connecting parts 34 ... Burner head 37 ... Pilot burners 40, 60 ... Thermosensitive parts (bimetal) 41, 61 ... Heat insulation parts

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Taiichiro Sakamoto 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Tochiki Kiki Co., Ltd. (72) Hideo Nishimura 43-1, Uozakihama-cho, Higashinada-ku, Kobe-shi No. Within Nippon Europe Co., Ltd. (72) Inventor Yukitoshi Nagata 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu-shi, Fukuoka Prefecture

Claims (3)

[Claims] 1. A vaporizing section for vaporizing a liquid fuel, a heat receiving section for receiving heat from a heat source and conducting the heat to the vaporizing section, the heat receiving section being separable from the vaporizing section. When the temperature of the vaporizing section exceeds a first predetermined temperature, the heat conduction path from the heat receiving section to the vaporizing section is cut by separating the heat receiving section from the vaporizing section, and the temperature of the vaporizing section is reduced. When the temperature falls below the first predetermined temperature or a second predetermined temperature lower than the first predetermined temperature, a heat conduction path from the heat reception unit to the vaporization unit is caused by contacting the heat reception unit with the vaporization unit. A liquid fuel vaporization and combustion apparatus, comprising: a heat transfer control means to be formed. 2. The heat conduction control means includes a thermosensitive body whose shape or size changes according to the temperature of the vaporizing section,
2. A heat conduction path from the heat receiving section to the vaporizing section by changing a relative position of the heat receiving section to the vaporizing section by changing a shape or a size of the temperature sensing element. Liquid fuel vaporization combustion apparatus according to any one of the above. 3. The apparatus according to claim 2, wherein the temperature sensing element is a bimetal.