JPS59202307A - Evaporating device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of unevenness in combustion and to perform stable evaporation during evaporation at high temperature, by a method wherein an air guide is installed to the center of the bottom of an evaporating cylinder, and a combustion air and the fuel are exhausted in the direction of a swirl into the evaporating cylinder through a supply opening. CONSTITUTION:When, with an evaporating cylinder 2 heated to a given temperature, a combustion fan 4 and an oil feed pump 3 are operated, the combustion air and the fuel are fed in a swirled condition to the inner peripheral wall of the evaporating cylinder 2 through supply openings 53a and 53b in an air guide 50 and oil feed nozzles 9a and 9b which face on the supply openings. The fuel, making contact with the heated inner wall of the evaporating cylinder 2, is evaporated as it is rolled in the evaporating cylinder 2 with the aid of the swirl flow of the combustion air in an evaporating chamber 20, and is mixed with the combustion air to feed the mixture in a mixing chamber 21. This enables prevention of the occurrence of unevenness in combustion, permits stable evaporation of the fuel during evaporation at high temperature, and enables prevention of discharge of unevaporated particle into the mixing chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vaporization device for vaporizing liquid fuel and mixing it with combustion air.

A conventional vaporizer of this type is shown in FIG. 1 and will be described below. A fuel supply pipe 5 and a blower pipe 6 connected to a fuel pump 3 and a combustion fan 4, respectively, are connected to the lower bottom surface of the pot-shaped vaporization pipe 2 which is heated by the heater 1.
An air guide 7 is provided on the inner bottom surface of the vaporizing cylinder 2, and a fuel nozzle 9 is opened at an outlet 8 of the air guide 7. Further, in the upper part of the vaporization tube 2, there is a rectification tube 11 provided with a large number of small holes 1o, and a combustion tube 13 made of wire mesh is connected to the rectification tube 11 around the rectification tube 11, which is provided with a rectification space 12.
is arranged, and its upper end is closed by a mixing cap 14. Furthermore, an outer cylinder 17 whose upper end is closed by an exhaust cap 16 is disposed around the combustion cylinder 13 via an exhaust space 15 . Further, a mixing plate 19 with a mixture passage 18 is disposed at the upper opening of the vaporization tube 2, and a vaporization chamber 20 is partitioned from the vaporization tube 2. The mixing chamber 21 is divided by. Further, the lower end of the outer cylinder 17 is supported by an exhaust pipe 23 having an exhaust port 22 in its side wall.

In the above configuration, when the heater 1 is energized and the vaporization tube °2 is heated to a predetermined temperature, the refueling pole 3 and the combustion fan 4 are activated to send liquid fuel and combustion air to the vaporization chamber 2o via the air guide 7. supply The liquid fuel that entered the vaporization chamber 14 is vaporized on the inner wall of the heated vaporization cylinder 2,
It mixes with combustion air and enters the mixing chamber 21 from the vaporization chamber 20 through the mixing plate 19. The air-fuel mixture that has entered the mixing chamber 21 is further mixed evenly and ejected from the small hole 1o of the rectifying tube 11, and is ignited by an ignition device (not shown) to cause uniform combustion on the surface of the combustion tube 13. . When combustion occurs, the combustion tube 13 becomes red hot due to the heat of combustion, radiating radiant heat to its surroundings, and the combustion exhaust gas passes through the exhaust space 16 and is discharged through the exhaust port 22 opened near the vaporization tube 2. However, at this time, the vaporizing peripheral wall of the vaporizing tube 2 is heated, and the recovered heat keeps the vaporizing tube 2 at a temperature sufficient for vaporization, so that the power supply to the heater 1 is stopped.

However, in the conventional example, the liquid fuel discharged into the vaporization chamber 20 is vaporized against the inner wall of the vaporization cylinder 2 facing the fuel nozzle 9, and therefore enters the mixing chamber 21 through the mixture passage 18. The mixture tends to have uneven concentration of fuel vapor gas, which tends to cause uneven combustion in the combustion tube 13. 1. When the temperature of the vaporization cylinder 2 rises and the liquid fuel vaporizes in a film boiling state on the vaporization wall surface, the liquid fuel rolls on the bottom surface of the vaporization cylinder 2 in granular size, and the air flow inside the vaporization cylinder 2 increases. At the stagnation point, large fuel particles formed into radicals, making vaporization unstable. Further, when the liquid fuel discharged from the fuel supply nozzle 9 collides with the inner wall of the vaporization cylinder 2, a part of the liquid fuel becomes small particles and bounces off, and instead of being vaporized in the vaporization chamber 20, the liquid fuel flows into the air-fuel mixture passage 18 as unvaporized particles. The flame passes through the small hole 10 of the straightening tube 11 and reaches the combustion tube 13, where it burns and generates yellow flame, which has the disadvantage of disturbing uniform combustion in the combustion tube 13.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned drawbacks of the conventional technology by improving the structure for supplying combustion air and fuel into the carburetor cylinder.
The purpose is to prevent uneven combustion, stabilize vaporization during high-temperature vaporization, and prevent unvaporized particles from being discharged into the mixing chamber.

Structure of the Invention In order to achieve this object, the present invention provides an air guide at the center of the lower bottom surface of the carburetor cylinder, and discharges combustion air and fuel into the carburetor cylinder from its outlet in a swirling direction.

With this configuration, the fuel discharged from the refueling nozzle collides with the vaporization wall and then vaporizes while swirling inside the vaporization cylinder together with the combustion air.The fuel is vaporized all around the vaporization cylinder and mixed with the combustion air. This eliminates uneven combustion in the 9 combustion cylinders, and since no stagnation of combustion air flow occurs in the vaporization cylinder, fuel particles do not become large and accumulate, and stable vaporization is performed. In addition, since swirling force is acting on the fuel, some of the fuel particles that bounced off when the fuel discharged from the refueling nozzle collides with the vaporizer wall are also pressed against the inner wall of the vaporizer cylinder, and are carried away as unvaporized particles by the combustion air flow. It does not enter the mixing chamber and reach the straightening tube, and does not disturb combustion in the combustion tube.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 3 and 4. Note that parts that are the same as those in the conventional example in FIG. 1 are given the same numbers, and descriptions thereof will be omitted.

A blower tube 6 is connected to the center of the lower bottom surface of the vaporization tube 2, and an air guide 50 is arranged inside the vaporization tube.

The air guide 60 has a double structure of a heat shield tube 61 made of a thin plate of a material with poor heat transfer properties on the inside, and a heat transfer tube 52 made of a thick plate of a material with good heat transfer properties on the outside. Two openings are opened in each of the air outlets 53a and 6.
3b is formed.

Further, the heat shield cylinder 61 has a guide plate 64a inside.

64b is provided, and the diameter of the air guide 6Q is set to be smaller than that of the blower tube 6, so that the combustion air supplied from the blower tube 6 is swirled and sent into the vaporizing tube 2. Also, the blower tube 6
Refueling nozzles 9a, 9 inserted into the air guide 50
b is the air outlet 53a.

It opens facing 53b.

Next, the operation will be explained. When the vaporization cylinder 2 is heated to a predetermined temperature and the combustion fan 4 and fuel pump 3 are operated, the air outlet 63a of the air guide 50 opens.

53b and the fuel supply nozzles 9a, 9b facing there, combustion air and fuel are swirled and sent out to the inner circumferential wall of the vaporization cylinder 2. The fuel that has come into contact with the heated inner wall of the vaporization cylinder 2 is vaporized while rolling within the vaporization cylinder 2 due to the swirling flow of combustion air in the vaporization chamber 2Q, mixed with combustion air, and sent to the mixing chamber 21. The heat transfer tube 62 is heated to a high temperature to prevent re-liquefaction of the vaporized gas, and the heat shield tube 61 prevents the oil supply nozzles 9a and 9b from overheating due to the heat from the heat transfer tube 52. . In the vaporization chamber 20, the fuel is vaporized all around the inside of the vaporization cylinder 2 while swirling together with the combustion air, so that the mixture with the combustion air is uniform, and there is no stagnation of air flow in the vaporization chamber 20. Unvaporized particles of fuel do not coalesce into large particles and accumulate, and stable vaporization is performed. Still in the vaporization chamber 20, the unvaporized particles of the fuel are pressed against the inner peripheral wall of the vaporization tube 2 due to the centrifugal force caused by the swirling flow, and the unvaporized particles enter the mixing chamber 21 due to the combustion air flow and are absorbed in the combustion tube 13. Does not disturb combustion. In addition, since the air guide 50 that applies swirling force to the combustion air and fuel is located at the center of the bottom of the vaporization tube 2, the inner peripheral shape of the vaporization tube 2 may be a simple circle, and the swirling flow in the vaporization chamber 20 can be suppressed. without disturbing
Stable vaporization can be obtained. Furthermore, since the shape of the vaporizing cylinder 2 is simple and the weight is light, not only can the preheating time by energizing the heater 1 be shortened, but it is also easy to process.

Furthermore, the center of the bottom of the vaporization cylinder is located at a lower temperature than the peripheral wall of the vaporization cylinder 2 because it is away from the high-temperature peripheral wall of the vaporization cylinder 2 where the heater 1 is provided, and the fuel supply nozzle 9a.

Since the temperature of fuel nozzle 9b can be lowered, it is possible to eliminate odor caused by overheating of fuel supply nozzles 9a and 9b during preheating and extinguishing.

Effects of the Invention As is clear from the above explanation, since an air guide for sending combustion air and fuel in a swirling direction is provided at the center of the bottom of the carburetor, the fuel discharged into the vaporization chamber is a swirling flow of combustion air. At the same time, the mixture is vaporized and mixed while rolling all around the inside of the vaporization cylinder, so not only can a uniform air-fuel mixture be obtained, but also
Large particles caused by coalescence of unvaporized fuel particles do not accumulate in the vaporization cylinder and cause instability in vaporization.

Further, unvaporized particles do not fly out into the mixing chamber due to the centrifugal force caused by the swirling flow, so combustion is not disturbed. - Also, since the air guide is located in the center of the vaporization cylinder, the inner periphery of the vaporization cylinder is a simple circle, which does not cause any disturbance in the swirling flow, resulting in stable vaporization, and the weight of the vaporization cylinder is reduced, reducing the preheating time. is shortened, and since the high temperature side WED of the vaporizer cylinder is also located at a low temperature, the temperature of the fuel supply nozzle can be maintained low, and odor can be reduced.

[Brief explanation of the drawing]

Figure 1 is a longitudinal sectional view showing a conventional vaporizer, and Figure 2 is a vertical cross-sectional view of a conventional vaporizer.
3 is a longitudinal sectional view showing an embodiment of the vaporizer of the present invention, and FIG. 4 is a cross-sectional view taken along line A-A in the figure.
It is a sectional view taken along the B line. 1...Heater, 2...Carburizer tube, 3. Refueling pump, 4...Combustion fan, 6....Blow pipe, 9..Refueling nozzle, 5Q... air guide,
61... Heat shield tube, 62... Heat transfer tube, 5
3...Air outlet, 64...Guide plate. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure M 2 Figure 3 @ Figure 4

Claims (4)

[Claims] (1) A pot-shaped vaporization tube heated by a heater, a blower tube connected to the bottom of the vaporization tube and equipped with a combustion air supply means and a fuel supply means, and a blower tube provided at the center of the bottom of the vaporization tube from the blower tube. A vaporizer equipped with an air guide that blows out the supplied combustion air and fuel into a vaporizer cylinder in a swirling direction. (2) The vaporizer according to claim 1, wherein the diameter of the air guide is larger than the diameter of the blower tube. (3) The vaporizer according to claim 1, further comprising a guide plate for swirling combustion air inside the air guide. (4) The air guide is divided into two parts: the inner heat shield cylinder and the outer heat transfer cylinder.
The vaporizer according to claim 3, wherein the vaporizer has a heavy structure and the guide plate is provided in a heat shield cylinder. (@ The vaporizer according to claim 11, in which the air guide has a plurality of combustion air outlets.