JPH0526417A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE:To reduce noise of a blower while reducing occurrence of odor caused by a leakage of mixed gas. CONSTITUTION:A liquid fuel combustion device is comprised of a fuel nozzle 20, a gasifier device 10 for gasifying liquid fuel injected and supplied by the fuel nozzle 20 within it and pre-mixing the gasified gas with combustion air and supplying them to a combustion part 23, an air nozzle part 31 for supplying combustion air having a lateral air passage 30 and integrally formed with a peripheral wall 11 of the gasifier device 10 and a blower 15 for feeding combustion air to the air passage. The air passage 30 has a gradual small sectional area between an inlet port 30A and an outlet port 30B from the inlet port 30A toward the outlet port 30B and it has a tapered part having no vertical plane in the midway part of it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vaporizing type liquid fuel combustion apparatus mainly used for oil fan heaters, and more particularly to an air nozzle portion for supplying combustion air having a lateral air passage, which is a peripheral wall portion of a carburetor. The present invention relates to a liquid fuel combustion device that is integrally formed with a fuel cell.

[0002]

2. Description of the Related Art Generally, in this type of liquid fuel combustion apparatus, a vaporizer for vaporizing liquid fuel is internally provided with a connection port, and the tip end of an air nozzle is screwed into the connection port for vaporization. And the air nozzle are connected. The connection between the carburetor and the air nozzle is exposed inside the carburetor, and the pressure of the mixed gas in the carburetor is applied to the connection, so a sealant is applied to the connection to prevent gas leakage. Had been prevented. However, when the sealant is insufficient or the sealant deteriorates due to heat, there is a problem that the mixed gas inside the vaporizer leaks out from the connection portion to give off a bad odor.

Therefore, in recent years, Japanese Patent Application Laid-Open No. 3-20509.
As disclosed in the publication (see FIG. 4), the vaporizer 1
By integrally forming the air nozzle portion 4 for supplying combustion air having the air passage 3 on the peripheral wall 2 of the above, the mixed gas inside the carburetor 1 is prevented from leaking outside from the combustion portion.

[0004]

However, as shown in FIG. 4, the air passage 3 in the above-mentioned conventional device is as follows.
Between the inlet portion 3A and the outlet portion 3B, two tapered surface portions 3C and 3D having a cross-sectional area that gradually decreases from the inlet portion 3A side toward the outlet portion 3B side are formed, and these two tapered surface portions 3C are formed. , 3D, an annular vertical surface portion 3E
Although the ejection pressure of the combustion air supplied into the carburetor 1 was increased by forming the cylindrical surface portion 3F and the cylindrical surface portion 3F, in such an air passage 3, the blown air as indicated by the arrow is shown at the vertical surface portion 3E. Air turbulence occurred, which caused pressure loss. Therefore, the rotation speed of the blower that sends the combustion air to the air passage 3 must be increased to increase the amount of blown air, which causes a problem that the noise of the blower increases.

The present invention has been made in view of the above situation, and an object thereof is to reduce the noise of the blower while reducing the generation of odor due to the leakage of the mixed gas.

[0006]

According to the present invention, a fuel nozzle and a liquid fuel jetted and supplied by the fuel nozzle are vaporized inside, and the vaporized gas and combustion air are premixed and supplied to a combustion section. An air nozzle part having a lateral air passage, an air nozzle part for supplying combustion air which is integrally formed on the peripheral wall of the carburetor, and a blower for sending combustion air to the air passage. The air passage has a cross-sectional area between the inlet portion and the outlet portion that gradually decreases from the inlet portion side toward the outlet portion side, and is formed in a taper shape with no vertical surface in the middle. There is.

[0007]

As described above, since the air nozzle portion for supplying combustion air having the lateral air passage is integrally formed on the peripheral wall of the carburetor, the mixed gas in the carburetor is discharged to the outside of the combustion portion. Since there is no risk of leakage and the air passage has no vertical surface, the flow of combustion air in the air passage becomes closer to a laminar flow than in the conventional case, and the pressure loss in the air passage can be reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. 1 and 3, reference numeral 10 denotes a bottomed cylindrical carburetor having an open top.
A heater 12 made of a sheathed heater is embedded in the upper part of the peripheral wall 11 of 0. Reference numeral 13 is an elbow-type primary air pipe through which the primary air for combustion is flown, and one end of this primary air pipe 13 communicates with a blower 15 via a connecting pipe 14.
Reference numeral 16 denotes a fuel supply pipe through which liquid fuel (kerosene) flows. One end of the fuel supply pipe 16 is communicated with a fuel tank 18 via a pump 17 such as an electromagnetic pump, and the other end of the fuel supply pipe 16 is connected. The end is connected to the base end of the fuel nozzle 20 whose front end faces the vaporization chamber 19 inside the vaporizer 10,
Liquid fuel is jetted and supplied from the tip of the fuel nozzle 20 to the vaporization chamber 19. Further, the fuel tank 18 is provided with a detachable cartridge tank 21.

Reference numeral 22 denotes a diaphragm plate disposed in the upper opening of the vaporizer 10. A burner head 23 is fitted and mounted in the upper opening of the vaporizer 10 above the diaphragm plate 22. A wire mesh 24 is attached to both inner and outer surfaces (the inner wire mesh is omitted) of the peripheral wall of the burner head 23, and a large number of flame holes 25, 25 are formed. 26 is a vaporizer 10
The flame retaining plate is provided at the upper end of the flame retaining plate 26, and an annular standing wall 26B facing the flame hole 25 is formed on the outer peripheral edge of the horizontal portion 26A of the flame retaining plate 26.

Reference numeral 27 denotes a bottomed cylindrical burner case which is provided on the outer circumference of the carburetor 10 and surrounds the carburetor 10. Air is blown from the blower 15 into the burner case 27 through a secondary air pipe 28. Be done. In addition, the secondary air pipe 28
The tip outlet portion 28A of the above is penetrated through the peripheral wall of the burner case 27 to face the inside of the burner case 27, and a baffle plate 29 is provided in the burner case 27 so as to face the outlet portion 28A. There is.

Next, the carburetor 10 will be described in detail. The carburetor 10 is made of aluminum die-cast, and the peripheral wall 11 thereof has a sideways air through which the fuel nozzle 20 is coaxially inserted. An air nozzle portion 31 for supplying combustion air having a passage 30 is formed by integral molding.

The air passage 30 has an inlet portion 30A between an inlet portion 30A connected by fitting the other end of the primary air pipe 13 therein and an outlet portion 30B facing the vaporization chamber 19.
The first and second tapered surface portions 30C and 30D having a cross-sectional area gradually decreasing from the side toward the outlet portion 30B are formed continuously, and as shown in FIG.
The spread angle θ1 of the tapered surface portion 30C is set to about 35 degrees, and the spread angle θ2 of the second tapered surface portion 30D is set to about 7 degrees.
It is set to 0 degrees. Then, the inlet portion 30A and the outlet portion 3
There is no vertical plane between 0B and 0B.

Reference numeral 32 in FIG. 3 denotes an ignition electrode for igniting a mixed gas of vaporized gas and air ejected from the flame hole 25.
A frame rod 33 detects the flame F that has been ignited and also detects the oxygen concentration.

In the above-mentioned structure, when the carburetor 10 is heated to a predetermined temperature by energizing the heater 12, the blower 15 and the pump 17 are operated, liquid fuel is discharged from the fuel nozzle 20, and the primary air pipe 16 is discharged. Air nozzle part 31
Primary air for combustion is supplied into the vaporization chamber 19 via the.
At this time, the combustion air flowing through the air passage 30 of the air nozzle portion 31 has first and second tapered surface portions 30 whose cross-sectional areas gradually decrease from the inlet portion 30A side toward the outlet portion 30B.
The pressure is gradually increased by C and 30D, and the outlet 30
The liquid fuel ejected from B into the vaporization chamber 19 and ejected from the fuel nozzle 20 is brought into contact with the vaporization surface of the vaporization chamber 19 in the form of fine particles. The vaporized gas of the liquid fuel vaporized by contacting the vaporization surface mixes with the primary air for combustion, and this mixed gas enters the burner head 23 through the passage of the diaphragm plate 22, and the flame hole 2
Eject from 5. The jetted mixed gas is ignited by the ignition electrode 32.
Is ignited by the spark discharge of, and flame F is formed to start combustion.

According to this embodiment, the sideways air passage 30
Since the air nozzle portion 31 for supplying combustion air having the above is integrally formed on the peripheral wall 11 of the carburetor 10, the connection portion between the air nozzle portion 31 and the primary air pipe 13 is located at a position away from the vaporization chamber 19. In addition, since the positive pressure of the combustion air is applied to the connecting portion between the air nozzle portion 31 and the primary air pipe 13, the mixed gas in the vaporizing chamber 19 does not leak outside the burner head 23.

The air passage 30 is provided between the inlet portion 30A and the outlet portion 30B from the inlet portion 30A side to the outlet portion 30B.
It is configured by continuously forming the first and second tapered surface portions 30C and 30D whose cross-sectional areas gradually decrease toward the side, and since there is no vertical surface in the middle, as shown by the arrow in FIG. The flow of the combustion air is close to the laminar flow, turbulence does not occur inside the air passage and stagnation of air does not occur as in the conventional case, the pressure loss in the air passage 30 is reduced, and the air flow rate is reduced. Therefore, even if the number of rotations of the blower that sends the combustion air to the air passage 30 is reduced, a sufficient amount of air can be obtained and the blowing noise of the blower can be reduced.

[0017]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, it is of course possible to prevent gas leakage to areas other than the combustion section and reduce the generation of odor due to leakage of mixed gas.
Air pressure can be reduced by reducing the pressure loss in the air passage of the air nozzle section, and sufficient air volume can be obtained even when the number of revolutions of the air blower is reduced, thus reducing air flow noise.
It can be used as a quiet device.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a liquid fuel combustion apparatus showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a vaporizer of the same.

FIG. 3 is also an overall configuration diagram of a liquid fuel combustion apparatus according to an embodiment of the present invention.

FIG. 4 is a vertical cross-sectional view of a vaporizer showing a conventional example.

[Explanation of symbols]

 10 Vaporizer 11 Peripheral Wall of Vaporizer 15 Blower 20 Fuel Nozzle 23 Burner Head (Combustion Section) 30 Air Passage 30A Air Passage Inlet 30B Air Passage Outlet 30C First Tapered Surface 30D Second Tapered Surface 31 Air Nozzle part

Claims (1)

Claim: What is claimed is: 1. A fuel nozzle and a liquid fuel which is jetted and supplied by the fuel nozzle, is vaporized inside, and the vaporized gas and combustion air are premixed and supplied to a combustion section. And an air nozzle portion having a lateral air passage and integrally formed on the peripheral wall of the carburetor for supplying combustion air, and a blower for sending combustion air to the air passage. The passage is characterized in that a cross-sectional area between the inlet portion and the outlet portion is gradually reduced from the inlet portion side toward the outlet portion side, and is formed in a taper shape without a vertical surface in the middle thereof. And