JPS6346325B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a liquid fuel combustion device used in a heat source device as a household heater.

Conventional configurations and their problems Conventional combustion devices that perform surface combustion mainly use gaseous fuel, and there are few that use liquid fuel, and even those that use liquid fuel are found in some small home heaters. Only. A conventional example will be explained based on the configuration diagrams shown in FIGS. 2 and 3. The gaseous fuel combustor shown in FIG. 2 includes a wire mesh 15 and a perforated plate 1.
A secondary rectifier cylinder 1 is installed in a combustion cylinder 18 formed by
At the same time, one end of the combustion cylinder is closed by a closing cap 17-a, and the other end is connected to a blowing chamber 12 via a blowing passage 11 by a blowing fan 10. A secondary rectifying tube 1 is provided at the connecting portion between the blow chamber 12 and the combustion tube 18.
It has a partition wall 25 that is continuous with 6'. In addition, an air outlet 2 is provided at the part of the partition wall 25 connected to the secondary rectifying tube 16'.
6, and at the same time, a gaseous fuel nozzle 3' is provided. Simultaneously with the start of air blowing by driving the blower fan 10, gaseous fuel is injected into the secondary rectifier tube 16' from the gaseous fuel nozzle 3'. While being mixed within the secondary straightening tube 16', the mixture is further promoted between the combustion tube 18 and the secondary straightening tube 16', and combustion occurs on the surface of the wire mesh 15. However, in order to develop this as a combustor using liquid fuel, a state change process from liquid to gas is required, so an evaporation and vaporization section is required.

In the conventional example shown in FIG. 3, it is a small household heater, in which a ventilation passage 11 and a two-fluid nozzle 27 formed by a fuel atomization nozzle 3 are connected in a vaporization chamber 8'. A heater 7 is fixed to the back side of the bottom of the vaporization chamber 8', and a mixing plate 28, a rectifying tube 16, and a combustion tube 18 made of a wire mesh 15 are connected above. After the bottom heating surface 9 of the vaporization chamber 8' is heated to a certain temperature, air blowing by a blower fan (not shown) and fuel supply by a combustion pump (not shown) begin, and the fuel is heated in the vaporization chamber 8'. The mixture is premixed at the same time as it is vaporized, and after passing through the mixing plate 28, the mixture is further promoted and surface combustion is performed in the wire mesh flame hole 15.
Although the time for which the heater 7 is energized for heating the vaporization chamber 8' may be longer or shorter depending on the method of receiving combustion heat, a vaporization means is always present that vaporizes the liquid fuel on the heating surface 9 in the vaporization chamber 8'.

As described above, in the development and use of conventional surface combustion burners using gaseous fuel, it is necessary to have an evaporation and vaporization section and an additional structure for fuel atomization means. In addition, in conventional combustors that use liquid fuel, a state change (liquid → gas) is obtained by heating the liquid fuel on the heating surface of the vaporization chamber, but as time passes, the heating surface changes. Gradual accumulation and fixation of tar progresses. As a result, various phenomena were observed, including unevenness and changes in the mixing ratio, generation of combustion noise due to unstable flame holding, and deterioration of exhaust gas components (particularly CO, HC, etc.) during ignition and extinguishing.

OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks, it is an object of the present invention to suppress tar accumulation and adhesion in the vaporizing chamber, and to promote evaporation, vaporization, and mixing in the atmosphere of the path to the combustion section.

Structure of the Invention In order to eliminate the conventional drawbacks and achieve the above object, the present invention provides a premixing chamber provided between a fuel vaporization chamber and a combustion section, and a premixing chamber provided between a fuel vaporization chamber and a combustion section, and a rotatable atomization nozzles that inject fuel in the direction of the chamber heating surface and toward the premixing chamber when the temperature of the combustion section is higher than a predetermined temperature; an expansion type temperature detection element that emits an expansion pressure output when the temperature becomes higher than the temperature; and a rotating part that is operated by the expansion pressure output of the temperature detection element to move the atomization nozzle in the direction of the premixing chamber. It is prepared.

With the above configuration, the liquid fuel is injected into the vaporization chamber by the atomization nozzle and heated and vaporized only during initial combustion. After ignition, at the same time as combustion is detected, the expansion pressure of the temperature detection element increases and is propagated to the rotating part of the atomization nozzle, converting displacement into rotation, thereby rotating the ejection direction of the atomization nozzle by a certain angle. The liquid fuel is then supplied to the mixing chamber, which has a high-temperature atmosphere due to radiation and heat transfer, where it evaporates, vaporizes, and mixes in the mixing chamber atmosphere to continue combustion.

Therefore, the contact time between the liquid fuel and the vaporization chamber is shortened, and tar accumulation and adhesion are suppressed as much as possible. As a result, good surface combustion due to stable premixing is maintained and continued.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, in the fuel system, a fuel pump 2 and an atomization nozzle 3 are connected via an oil pipe 1, and the atomization nozzle 3 is connected to a rotating shaft 5 of a rotating part (rotating mechanism part) 4. During non-combustion and in the early stage of ignition, the jet nozzle 6 of the atomization nozzle 3 is installed directly on the heating surface 9 in the vaporization chamber 8' formed by the vaporization tube 8 in which the heater 7 is embedded. There is. Further, as a ventilation system, a ventilation fan 10 is connected via a ventilation passage 11 to one end of a support cylinder 13 that covers the vaporization cylinder 8 and forms a ventilation chamber 12 . The mixing chamber 14 includes a wire mesh flame hole 15 that forms a uniform flame surface,
A rectifier tube 16 made of a perforated plate is formed approximately concentrically on the inner peripheral surface of the wire mesh flame hole 15, and one end is connected to the vaporization chamber 8, and the other end is connected to the closed cap 1.
It is formed in the combustion cylinder 18 made up of 7-a. An outer cylinder 20 is connected approximately concentrically to the outer periphery of the combustion cylinder 18 via a combustion space 19 by a closing cap 17-b, and this outer cylinder 20 forms a passage for combustion gas to the outside of the cylinder. The support cylinder 13
and the closing cap 17-b. A filter 22 carrying a catalyst for purifying exhaust gas is provided on the air supply port 21 communicating with the combustion exhaust gas passage of the support tube 13. 23 is an ignition source provided near the wire mesh flame hole 15; and 24 is the outer cylinder 2.
This is an expansion type temperature sensing element adjacent to the surface of the support tube 13 near the wire mesh flame hole 15 to which the temperature sensor 0 is fixed. The temperature detection element 24 is connected to a fixed rotating part (rotating mechanism part) 4 of the atomization nozzle 3, and the connected interior is filled with replenisher.

In the above configuration, first, the heater 7 embedded in the vaporization cylinder 8 is energized, and the heating surface 9 in the vaporization chamber 8' is
After the temperature rises to a predetermined temperature, the blower fan 10 is driven to blow combustion air into the vaporization chamber 8' through the blower passage 11 and the blower chamber 12. Thereafter, the combustion pump 2 is driven, and fuel is supplied onto the heating surface 9 through the atomization nozzle 3 facing the heating surface 9 in the vaporization chamber 8', and instantaneously evaporated and vaporized. When the combustion air passes through the blow chamber 12 and the vaporization chamber 8', it is partially heated and mixed at the same time, further promoting mixing in the mixing chamber 14 and uniformly rectifying it through the perforated rectifier tube 16. The flame is ejected from the wire gauze hole 15 forming the combustion tube 18. The air-fuel mixture is ignited by the ignition source 23 that is energized at the same time as the blower fan 10, forming a flame on the surface of the wire mesh flame hole 15 and radiating heat. The air is forcibly discharged from the air inlet 21 of the support cylinder 13 through the filter 22 while contacting the outer periphery of the air. When the expansion type temperature detection element 24 detects a predetermined temperature, the ignition source 23 and the heater 7 are de-energized. At the same time, the expansion pressure rises and increases and propagates to the rotating part 4 of the atomization nozzle 3, and is converted from displacement to rotational movement, and the ejection direction of the atomization nozzle 3 gradually shifts to the mixing chamber 14 where a high temperature atmosphere is formed. and rotate by a certain angle. The liquid fuel is then directly injected into the mixing chamber 14 in a high-temperature atmosphere, where it is atomized, evaporated and vaporized during the flight, and mixing is promoted, passing through the straightening tube 16 and ejected from the wire gauze flame hole 15 to continue combustion. . In addition, the hole diameter on the rectifying cylinder 16 is
It is designed with sufficient consideration given to preventing backfire in high temperature areas.

Effects of the Invention As described above, according to the liquid fuel combustion device of the present invention, the premixing chamber provided between the vaporization chamber for fuel vaporization and the combustion section, and the vaporization chamber provided when the temperature of the combustion section is lower than a predetermined temperature. a rotatable atomization nozzle that injects fuel in the direction of the heating surface and in the direction of the premixing chamber when the temperature of the combustion section is higher than a predetermined temperature;
an expansion type temperature detection element that detects the temperature of the combustion part and emits an expansion pressure output when the combustion part becomes higher than a predetermined temperature; Since it is equipped with a rotating part that moves in the direction of the premixing chamber, the following effects can be expected.

(1) Due to its own combustion heat, it can evaporate and vaporize in the atmosphere.

(2) The contact time between the fuel and the heating surface of the vaporization chamber for fuel evaporation and vaporization can be suppressed as much as possible.

(3) The time for energizing the heater can be shortened as much as possible.

As a result, tar accumulation and adhesion on the heating surface of the vaporization chamber is suppressed, and stable evaporation and good surface combustion due to repeated vaporization are maintained and continued. Furthermore, clean ignition and extinguishing are maintained, and various combustion characteristics can be significantly improved. In addition, it is possible to save power by utilizing combustion heat.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the liquid fuel combustion device of the present invention, Fig. 2 is a longitudinal sectional view showing a conventional example of a surface combustion burner using gaseous fuel, and Fig. 3 is a longitudinal sectional view showing a conventional example of a surface combustion burner using gaseous fuel. FIG. 2 is a vertical cross-sectional view of a fuel vaporization section showing a conventional example in FIG. 3... Atomization nozzle, 4... Rotating part (rotating mechanism), 7... Heater, 8'... Vaporization chamber, 9...
Heating surface, 14... Mixing chamber, 24... Expansion type temperature sensing element.

Claims (1)

[Claims] 1. A premixing chamber provided between a vaporization chamber for fuel vaporization and a combustion section, and a premixing chamber provided in the direction of the heating surface of the vaporization chamber when the temperature of the combustion section is lower than a predetermined temperature, and when the temperature of the combustion section is higher than a predetermined temperature. rotatable atomization nozzles that respectively inject fuel in the direction of the mixing chamber;
an expansion type temperature detection element that detects the temperature of the combustion part and emits an expansion pressure output when the combustion part becomes higher than a predetermined temperature; a rotating part that moves in the direction of the premixing chamber.