JPH08121716A - Combustion device - Google Patents

Abstract

PURPOSE: To prevent the choking of a vaporizing element with tar produced and prevent malfunctioning from occurring so as to make the amount of combustion invariable for a long time and keep the combustion satisfactory. CONSTITUTION: A combustion device is provided with a burner seat 2 on which a burner is mounted in a vaporizing part 1, a heat-receiving wall 17 at the circumference of the burner seat 2, a nozzle 3 in the middle, and a vaporizing chamber 6 inside with a vaporizing element 7 is set radially from the nozzle 3, which all are formed in an integral structure and in a constitution having the wall thickness greater above the vaporizing chamber 6 than that of a lower wall. This constitution makes it possible to expand the area available for the vaporization inside the vaporizing element 7 so as to inhibit choking with tar through dispersion of the formation of tar so that the amount of combustion can be prevented from falling and abnormal combustion from occurring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device for vaporizing a liquid fuel and ejecting the vaporized gas from a nozzle portion to burn it.

[0002]

2. Description of the Related Art Conventionally, in this type of combustion apparatus, as shown in FIG. 5, fuel is supplied to a tank 21 from a cartridge tank 22, and the fuel in the tank 21 is supplied to a vaporization section 24 by a pump 23. Then, the fuel is diffused by the vaporization element in the vaporization section 24, further heated and vaporized into a fuel gas, which is ejected in the horizontal direction from the nozzle section 25. The fuel gas ejected from the nozzle portion 25 is mixed with the fuel gas and the primary air in the mixing pipe 26 provided on the downstream side of the vaporization portion 24 while sucking the primary air by the ejector effect, and is integrated with the mixing pipe 26. Is supplied to the burner section 27 constituted by and is burned. The combustion gas generated by the combustion is guided upward by a combustion cylinder 28 arranged so as to cover the periphery of the burner portion 27, and is mixed with an air flow from the blower 30 by a duct 29 covering the combustion cylinder 28 to generate warm air. Is discharged outside the equipment and used for heating, etc. Then, in this type of combustion device, if the drive frequency of the pump 23 and the applied voltage are changed to adjust the fuel supply amount,
The amount of secondary air also increases / decreases accordingly, and the amount of combustion can be changed while the ratio of fuel and combustion air is kept substantially constant.

[0003]

However, in the combustion device having such a structure, when a fuel containing a large amount of high boiling point components such as a deteriorated fuel that has been left for a long time and oxidized is used, the tar in the vaporization element that diffuses and vaporizes the fuel. However, there is a problem that minute amount is generated, clogging of the vaporization element and poor vaporization occur, and the amount of combustion decreases and abnormal combustion occurs.

That is, when the vaporization element provided in the vaporization chamber is clogged with tar, the resistance of the flow passage in the vaporization chamber increases, and the resistance reduces the amount of fuel supplied from the pump. And the amount of combustion air sucked by the jet of the fuel gas decreases, the ratio of the fuel and the air amount changes, which causes deterioration of the combustion state. In addition, the pores of the vaporizing element cause the fuel that had been widely diffused and vaporized in the vaporizing element to be clogged with the vaporizing element, which suppresses diffusion and causes irregular pulsating vaporization due to local vaporization. I was getting tired.

The present invention is intended to solve the above problems, and it is an object of the present invention to prevent clogging of a vaporization element due to tar, prevent vaporization failure, and maintain a good combustion state for a long period of time.

[0006]

To achieve the above object, the present invention communicates with a vaporizing section for vaporizing fuel, a heater for heating the vaporizing section, and the vaporizing section, and ejects vaporized fuel gas. The burner receiving seat includes a nozzle portion, a burner portion that burns fuel gas ejected from the nozzle portion, and a burner receiving seat that mounts the burner portion. The nozzle part connected by the seat and the rib part, the opening part which is open with the rib part and the vaporization chamber between the burner receiving seat and the nozzle part, and the fuel supply port is arranged at the end part in the radial direction from the center. The provided vaporizing chamber is integrally formed and disposed, the upper wall thickness of the vaporizing chamber is made thicker than the lower wall thickness, and an inorganic porous vaporizing element is provided inside.

Also, a gap is provided between the lower surface of the vaporization chamber inner wall and the vaporization element. The density of the vaporization element made of an inorganic porous material is such that the upper part is dense and the lower part is coarse.

[0008]

In this type of combustion apparatus, at the time of combustion, the fuel supplied from the fuel supply port to the vaporization chamber diffuses in the vaporization element due to the capillarity of the vaporization element provided in the vaporization chamber, and the heat is transferred from the burner receiving seat by heat conduction. The fuel gas vaporized while being gradually heated by the combustion heat supplied, and the vaporized fuel gas is ejected from the communicating nozzle.At this time, if the temperature distribution in the vaporization chamber is inadequate, tar is locally generated. A decrease in the combustion amount due to the clogging of the vaporization element with tar occurs early. For example, when the amount of heat given to the vaporization chamber is almost constant from the inlet to the outlet of the fuel, the fuel is vaporized rapidly near the inlet, so that tar is concentrated in the same portion and locally clogs.

According to the present invention, according to the above-described structure, at the time of combustion, the vicinity of the outlet of the vaporizing chamber is heated from the burner receiving seat through the rib portion, but the central portion of the vaporizing chamber conducts heat from the heat receiving portion of the burner receiving seat. It is heated from above by heat. And the built-in vaporization element is heated by heat conduction from the wall surface of the vaporization chamber, but since the vaporization chamber is heated from the top and the wall thickness of the wall surface is thin at the bottom, the temperature of the vaporization element is high at the top, Lower bottom.

Therefore, the fuel supplied from the fuel supply port diffuses in the vaporizing element in the liquid state and is vaporized while being gradually heated from the inlet to the outlet, but the temperature of the vaporizing element is high in the upper part and low in the lower part. Since it is low, much of the fuel is vaporized near the line connecting the upper part of the vaporizing element near the inlet and the lower part of the vaporizing element near the outlet. Therefore, since tar is also dispersed and produced in a wide range, clogging is not locally generated, and the combustion amount is not rapidly reduced.

Further, by disposing the vaporizing element through the gap between the lower surface of the vaporizing chamber and the lower portion, the heat conduction amount from the vaporizing chamber is small in the lower portion of the vaporizing element, and the temperature upper portion of the vaporizing element is high and the lower portion is low. The same effect as above can be obtained.

[0012] Further, the vaporization element density is made higher in the upper part,
By roughening the lower portion, the heat conduction from the vaporization chamber to the vaporization element is large in the upper portion and small in the lower portion, and the temperature upper portion of the vaporization element is higher and the lower portion is lower, so that the same effect as above can be obtained. .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, reference numeral 1 denotes a vaporization portion, which is provided with a circular burner receiving seat 2 on an upper portion thereof, and which is located substantially at the center of the burner receiving seat 2 and which is connected to the burner receiving seat 2 by a rib portion 11. The portion 3 is arranged, and the opening 4 into which the combustion air flows is opened between the burner receiving seat 2 and the nozzle portion 3. Reference numeral 6 denotes a vaporization chamber, one end of which is communicated with the nozzle portion 3 through the communication port 5, which extends in the radial direction and is provided with the fuel supply port 8 at the other end, and the wall thickness of the upper portion is thicker than that of the lower portion. . A columnar vaporization element 7 made of an inorganic porous material is disposed in the vaporization chamber 6. Reference numeral 10 is a temperature detecting means for detecting the temperature of the vaporization section 1, and 9
Is a heater provided along the back surface of the burner receiving seat 2 excluding the vaporization chamber 6. Reference numeral 12 is a mixing pipe located above the nozzle portion 3 and placed on the burner receiving seat 2, 13 is a burner portion having a large number of flame hole portions 14 formed in the lower peripheral wall, and 16 is a flame hole portion 14.
The burner ring 17 is arranged so as to cover the heat sink, and 17 is a heat receiving portion provided on the burner receiving seat 2.

In the above structure, the fuel sent from the fuel supply port 8 to the vaporization chamber 6 is vaporized in the vaporization chamber 6 maintained at a predetermined temperature by the heater 9 and the temperature detecting means 10 to become a fuel gas. It spouts from the nozzle part 3. When the fuel gas is ejected from the nozzle portion 3, the primary air is sucked from the opening portion 4 by the ejector effect, flows into the burner portion 13 while being mixed with the fuel gas in the mixing pipe 12, and burns at the flame hole portion 14.

When the combustion is started, the flame 15 burned in the flame hole portion 14 heats the heat receiving portion 17, and the conductive heat from the flame hole portion 14 is transferred to the burner receiving seat 2 so that the vaporizing portion 1 has a predetermined temperature or higher. Then, the signal from the temperature detecting means 10 is controlled by a control unit (not shown) to stop energizing the heater 9, and thereafter the vaporization unit 1 is maintained at a constant temperature only by the combustion heat.

In the vaporizing chamber 6 at the time of combustion, a rib portion 1 connected to a burner receiving seat 2 is provided in the vicinity of a communication port 5 serving as a fuel gas outlet.
1, heat is directly transferred from the burner receiving seat 2 to the vicinity of the central portion in the longitudinal direction from the upper portion, and the vaporization element 7 is heated from the wall surface of the vaporization chamber 6 by conduction heat. Therefore, the vaporization element 7 is heated so that the upper part of the temperature distribution is high and the lower part is low.

During the process in which the fuel vaporizes in the vaporization chamber 6, the fuel supplied from the fuel supply port 8 into the vaporization chamber 6 is
The inside of the pores of the vaporizing element 7 having porosity is diffused by the capillary phenomenon toward the outlet and is vaporized while being gradually heated, and becomes fuel gas and is ejected from the nozzle portion 3 through the communication port 5. At this time, when the vaporization element 7 is heated at a uniform temperature, the vicinity of the fuel supply port 8 is cooled by the supplied fuel and becomes lower than other parts, but when the fuel reaches the vaporization temperature after a predetermined distance. It vaporizes rapidly in the vicinity of the surface in the cross-sectional direction without sufficiently diffusing in the vaporization element 7, and tar is locally generated. Further, the fuel intermittently supplied from the pump (not shown) is rapidly vaporized, so that the combustion gas is ejected from the nozzle portion 3 while pulsating, and stable combustion cannot be obtained.
Then, if vaporization and combustion are continued as they are, the generated tar locally concentrates and accumulates, so that the passage resistance in the vaporization element 7 increases and the fuel supply capacity of the pump lowers, leading to a reduction in the combustion amount.

According to the construction of this embodiment, since the wall thickness of the vaporization chamber 6 is made thicker at the upper portion than at the lower portion, the temperature in the vaporization chamber 6 heated from the upper portion in the vicinity of the outlet and in the central portion is the upper surface. Is higher and the lower surface is lower. Therefore, the temperature of the vaporization element 7 heated by the conductive heat from the wall surface of the vaporization chamber 6 is also high in the upper part and low in the lower part. When the fuel is supplied from the fuel supply port 8, the fuel is cooled by the fuel near the inlet, so that the line that connects the upper part of the vaporizing element near the inlet and the lower part of the vaporizing element near the outlet becomes the vaporization temperature and much vaporizes near that line. .
Therefore, since tar is also dispersed and produced in a wide range, clogging is not locally generated, and the combustion amount is not rapidly reduced. Further, the fuel intermittently supplied from the pump is gradually vaporized from the upper part near the inlet, so that pulsating ejection from the nozzle part can be suppressed.

Next, as shown in FIG. 3, by providing a gap 6a between the lower surface of the vaporization chamber 6 and the vaporization element 7, heat conduction to the lower portion of the vaporization element 7 is suppressed, and the temperature of the vaporization element 7 is increased. Is high and the lower part is low, and the same effect as described above can be obtained.

As shown in FIG. 4, the vaporization element 7 is divided into upper and lower parts so that the upper portion of the vaporization element has a higher density and the lower portion has a lower density, so that the vaporization element 7 is transferred by heat conduction from the vaporization chamber 6. The amount of heat applied is high in the upper part and low in the lower part. Therefore, the temperature of the vaporization element 7 is high in the upper part and low in the lower part, and the same effect as described above can be obtained.

[0021]

As described above, in the combustion apparatus of the present invention, the wall thickness of the vaporization chamber containing the vaporization element made of an inorganic porous material is made thicker in the upper part and thinner in the lower part, so that It is possible to expand the vaporization area of the above and disperse the tar generation to prevent the decrease of the combustion amount and the above combustion.

Further, by providing a gap between the lower surface of the vaporizing chamber and the vaporizing element, the vaporizing area in the vaporizing element is enlarged and tar generation is dispersed to prevent a decrease in combustion amount and abnormal combustion. can do.

Further, by making the density of the vaporizing element dense in the upper portion and roughening the lower portion, the vaporizing area in the vaporizing element is enlarged, and the tar generation is dispersed to prevent a decrease in the combustion amount and abnormal combustion. be able to.

[Brief description of drawings]

FIG. 1 is a sectional view of a combustion apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a burner seat of the combustion device.

FIG. 3 is a sectional view of a combustion apparatus showing another embodiment of the present invention.

FIG. 4 is a sectional view of a combustion apparatus showing another embodiment of the present invention.

FIG. 5 is a sectional view of a conventional combustion device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vaporizing section 2 Burner receiving seat 3 Nozzle section 4 Opening section 5 Communication section 6 Vaporizing chamber 7 Vaporizing element 8 Fuel supply port 9 Heater 10 Temperature detecting section 11 Rib section 13 Burner section 17 Heat receiving section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinya Nakagawa 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Takehiko Shigeoka, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A vaporization section for vaporizing fuel, a heater for heating the vaporization section, a nozzle section communicating with the vaporization section for ejecting vaporized fuel gas, and burning the fuel gas ejected from the nozzle section. The burner receiving seat is provided with a burner portion and a burner receiving seat on which the burner portion is placed. The burner receiving seat has a heat receiving wall on an outer periphery, the nozzle portion connected to the burner receiving seat and a rib portion substantially at the center, and a burner receiving seat. An opening formed by leaving a rib portion and a vaporization chamber between the seat and the nozzle portion, and a vaporization chamber that is arranged in the radial direction from the center and has a fuel supply port at the end are integrally formed and arranged. A combustion apparatus in which the vaporization chamber has an upper wall thickness thicker than a lower wall thickness and an inorganic porous vaporization element is disposed in the vaporization chamber. 2. A vaporization section for vaporizing fuel, a heater for heating the vaporization section, a nozzle section communicating with the vaporization section for ejecting vaporized fuel gas, and burning the fuel gas ejected from the nozzle section. The burner receiving seat includes a burner portion and a burner receiving seat on which the burner portion is placed. The burner receiving seat has a heat receiving wall on an outer periphery, the nozzle portion connected to the burner receiving seat and a rib portion at substantially the center, and the burner receiving seat. The rib portion and the vaporization chamber are opened between the nozzle and the nozzle portion, and the vaporization chamber, which is arranged in the radial direction from the center and has the fuel supply port at the end, is integrally formed and disposed. A combustion apparatus in which a vaporization element made of an inorganic porous material is disposed in the vaporization chamber with a gap provided between the vaporization chamber and a lower surface of the vaporization chamber. 3. A vaporization section for vaporizing fuel, a heater for heating the vaporization section, a nozzle section communicating with the vaporization section for ejecting vaporized fuel gas, and burning the fuel gas ejected from the nozzle section. The burner receiving seat includes a burner portion and a burner receiving seat on which the burner portion is placed. The burner receiving seat has a heat receiving wall on an outer periphery, the nozzle portion connected to the burner receiving seat and a rib portion at substantially the center, and the burner receiving seat. The rib portion and the vaporization chamber are opened between the nozzle and the nozzle portion, and the vaporization chamber, which is arranged in the radial direction from the center and has the fuel supply port at the end, is integrally formed and disposed. A combustion device in which a vaporization element made of an inorganic porous material having a dense upper portion and a coarse lower portion is arranged in the vaporization chamber.