JPH0868510A - Liquid fuel combustion device - Google Patents

Abstract

PURPOSE: To provide a vaporizing type liquid fuel combustion device and to obtain a fuel spraying node which generates no inconvenience even when a broad range for adjusting the amount of combustion is used. CONSTITUTION: A liquid fuel combustion device comprises a blast passage 16 connected to a blower 15 for feeding air for combustion, a primary air passage 17 set in the blast passage 16, a vaporizer 13 for vaporizing fuel, a mixing chamber 25 connected to the downstream side of the vaporizer 13. a burner head 11 formed in the downstream side of the mixing chamber 25 and a nozzle 20 provided in the primary air passage 17 and connected to an oil transfer pipe 21. This nozzle 20 has a plurality of spray holes symmetric relative to a central axis on the conical surface of a tip end part whose conical inner and outer surfaces are located on the same central axis and the tip end part has a diameter smaller than that of the other part. In the connecting part of the oil transfer pipe 21 and the nozzle 20, a step part is provided so that the nozzle 20 protrudes downward and a part protruding inward is provided on an inner wall part in the upstream side of a position corresponding to the nozzle 20 in the primary air passage 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel combustion apparatus used as a heat source for hot water supply, heating, etc. for home use, in which a fuel is vaporized by a vaporizer and burned.

[0002]

2. Description of the Related Art A liquid fuel combustion apparatus of the type that vaporizes and burns liquid fuel will be described with reference to FIG.

In FIG. 5, reference numeral 1 is a burner head, which is surrounded by a U-shaped burner head case 2 and a U-shaped facing carburetor 3 having a heater. Reference numeral 4 denotes a vaporizer lid which is attached to the vaporizer 3 and seals vaporized gas. Two vaporizer nozzles 5 having an opening above the vaporizer lid 4 for ejecting fuel to the vaporizer 3 are provided in the vaporizer 3. It is provided facing the surface. The nozzle 5 ejects the fuel sent from the two electromagnetic pumps 6 for fuel supply to the vaporizer 3 via the oil supply pipe 7. A blower 8 supplies combustion air, and is attached to the burner head case 2 and a burner case 9 arranged outside the mixing chamber 10 described later. Reference numeral 10 denotes a mixing chamber that supplies the vaporized gas in the vaporizer 3 to the burner head 1, and is installed below the vaporizer 3 and the burner head 1.

[0004]

With such a conventional configuration, when the fuel is sprayed onto the carburetor 3 to be vaporized, the
When fuel is ejected from each nozzle, the temperature of the carburetor at the point where the fuel hits remarkably drops and falls to the bottom of the carburetor before vaporization is completed, resulting in poor combustion. For that 2
It was necessary to disperse the fuel with each nozzle to reduce the vaporization load. However, if two nozzles are used, two electromagnetic pumps 6 for supplying fuel are also required, resulting in a significantly high manufacturing cost.

On the other hand, when attempting to vaporize the fuel ejected from one nozzle, the vaporizer 3 is required to complete the vaporization.
Had to be bigger. However, when the carburetor 3 becomes large, it takes too much time to reach a predetermined temperature at which the carburetor 3 can vaporize the fuel, resulting in extremely poor usability, and when the carburetor becomes large, the components around the carburetor also become large. The material cost was also high because it became large.

Further, if the combustion amount adjustment range is increased with one nozzle, when the combustion amount is reduced, the ejection speed from the nozzle 5 decreases, so that fuel accumulates at the tip of the nozzle 5 and the worst case occurs. In the case, there was a risk of leaking out of the vaporizer 3.

The present invention solves the above problems by reducing the vaporization load for vaporizing the fuel to reduce the manufacturing cost, and even when the combustion amount adjustment range is large, the accumulation of fuel at the tip of the nozzle is prevented. The purpose is to reduce the amount of fuel and prevent the fuel from leaking out of the carburetor. It is another object of the present invention to provide an inexpensive liquid fuel combustion device with simple processing.

[0008]

In order to solve the above problems, in a liquid fuel combustion apparatus of the present invention, a blower for supplying combustion air, a blower passage connected to the blower, and a liquid fuel are vaporized. A vaporizer, a primary air passage in the air passage extending to the vaporizer inlet, a secondary air passage formed outside the primary air passage, and a mixer continuously connected to the vaporizer downstream side A chamber, a burner head formed on the downstream side of the mixing chamber, and a pump for supplying liquid fuel,
An oil feed pipe that conveys liquid fuel from a pump, and an inner surface and an outer surface that are connected to the oil feed pipe in the primary air passage and that are on the same central axis are formed into a conical surface of a conical tip. A nozzle having a plurality of ejection holes symmetrically with respect to the central axis and having a tip with a small diameter is provided.

Further, at the connecting portion between the oil feed pipe and the nozzle, a step is provided so that the lower end of the nozzle projects downward from the oil feed pipe.

Further, the inner wall surface on the upstream side of the position corresponding to the nozzle of the primary air passage is provided with an inward projection.

Further, the projecting portion is integrally machined so as to project inwardly of the primary air passage.

[0012]

In the liquid fuel combustion apparatus of the present invention, the fuel sent from one electromagnetic pump is jetted from a plurality of jet holes, so that the fuel can be dispersed, so that the vaporization area in the vaporizer can be effectively utilized, and the vaporizer can be effectively used. The overall size can be made compact. Further, since the conical surface of the nozzle is used diagonally, it is possible to prevent deviation of the flow rate due to the interference of the spray between the nozzle openings. Furthermore, since the inner and outer surfaces of the nozzle are conical surfaces having the same central axis, the depths of the ejection holes are made the same and the flow path resistance is made uniform, so it is possible to eliminate flow rate variations. Further, since the tip portion of the nozzle has a small diameter, it is possible to reduce the accumulation of fuel in the tip portion of the nozzle.

Further, since the step is provided so that the lower end of the nozzle projects downward from the oil supply pipe, it is possible to prevent the fuel accumulated at the tip of the nozzle from leaking along the oil supply pipe.

Further, since the inner wall surface on the upstream side of the position corresponding to the nozzle of the primary air passage is provided with the protruding portion inward, even if the fuel drops into the primary air passage, the protruding portion is formed. Thus, it is possible to prevent the fuel from leaking out of the primary air passage.

Further, since the projecting portion is integrally machined so as to project inwardly of the primary air passage, it is possible to prevent leakage of liquid droplets and prevent deformation of the primary air passage by simple machining.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the liquid fuel combustion apparatus of the present invention will be described below with reference to the drawings.

In FIG. 1, a burner head 11 is surrounded by a U-shaped burner head case 12 and a U-shaped opening surface surrounded by a vaporizer 13 having a heater.
A vaporizer lid 14 is attached to the vaporizer 13 to seal the vaporized gas. A blower 15 supplies combustion air, and a blower path 16 is connected to the blower. 17 is an air duct 16
It is set so as to face the opening 18 provided above the carburetor lid 14 with the primary air passage set therein. Reference numeral 19 is an air amount adjusting means provided on the upstream side of the primary air passage 16 and is opened and closed by a drive device (not shown) according to the combustion amount to adjust the primary and secondary air. Reference numeral 20 denotes a nozzle set in the primary air passage 16, to which an oil feed pipe 21 is connected. An electromagnetic pump 22 pumps up fuel from a fuel tank (not shown) and supplies it to the nozzle 20 via an oil feed pipe 21. A burner case 23 is provided so as to have a gap serving as a secondary air passage 24 with the burner head case 12. A mixing chamber 25 serves as a passage for supplying the vaporized gas in the vaporizer 13 to the burner head 11, and is attached to the lower portions of the vaporizer 13 and the burner head 11.

As shown in FIG. 2, the nozzle 20 has a tip portion 2
6 is at the same angle and perpendicular to the conical surfaces of the conical inner surface 28 and outer surface 29 on the same central axis 27,
Further, it has a plurality of ejection holes 30 symmetrical to the central axis 27. Further, the tip portion 26 has a small diameter.

FIG. 3 shows a second embodiment of the present invention, in which a step 31 is provided at the connecting portion between the oil feed pipe 21 and the nozzle 20 so that the nozzle 20 projects below the oil feed pipe 21. It has a structure. Further, a protrusion 32 is provided inward on the inner wall surface of the primary air passage 16 upstream of the position corresponding to the nozzle 20.

In the above structure, the fuel sent from the electromagnetic pump 22 is supplied to the nozzle 20 via the oil sending pipe 21. The fuel that has entered the nozzle 20 is ejected from the ejection hole 30 at the tip. The ejected fuel is a vaporizer 13.
The fuel can be dispersed because it strikes the surface of the fuel vaporized at an angle. Therefore, the inner surface of the vaporizer 13 can be effectively used, and stable vaporization can be performed.
Further, since the ejection holes 30 provided in the nozzle 20 use the conical surface diagonally, it is possible to prevent the deviation of the flow rate due to the interference of the spray between the ejection holes 31. Furthermore, since the ejection holes 31 are formed in the conical inner surface 28 and outer surface 29 having the same angle and the same central axis, the depth of the ejection holes 31 becomes constant and the flow path resistance can be made uniform. Variations in flow rate also disappear. Further, since the tip portion 26 of the nozzle 20 has a smaller diameter than the other portions, even if the amount of combustion is reduced and the jet flow velocity of the fuel is reduced to cause the liquid pool of the fuel at the tip portion 26,
Since the fuel is cut off at the step portion of the tip portion 26, it is possible to prevent the liquid pool from being minimized.

Furthermore, since the step 31 is provided at the connecting portion between the oil feed pipe 21 and the nozzle 20 so that the nozzle 20 projects below the oil feed pipe 21, the amount of the liquid pool should be increased. Even when the fuel spreads to the lower surface of the nozzle 20, the edge is cut off at the step 31 and the fuel is fed to the oil feeding pipe 21.
It does not leak through. Further, in the worst case, the fuel accumulated in the step 31 may fall into the primary air passage 16. A protrusion 32 is provided inward on the lower surface of the primary air passage 16 upstream of the position corresponding to the nozzle 20.
It is possible to prevent the dropped fuel droplets from leaking out of the primary air passage 16.

FIG. 4 shows a third embodiment of the present invention, in which the protruding portion 32 is integrally formed in the primary air passage 16 by rib forming or the like. As a result, there is no need for welding or the like, and the protrusion 32 for preventing leakage is formed by simple processing, and the effect of preventing deformation of the primary air passage 16 is also obtained. If the same processing is applied to not only the bottom surface of the primary air passage 16 but also the side surface thereof, it is more effective in preventing deformation.

[0023]

As described above, according to the liquid fuel combustion apparatus of the present invention, a plurality of nozzles are ejected symmetrically with respect to the central axis on the conical surface of the tip of which the inner surface and the outer surface on the same central axis are conical. By providing the holes, the fuel can be uniformly dispersed in the carburetor, and the vaporization area in the carburetor can be effectively used. Therefore, a small carburetor can provide a large amount of combustion, and the device can be downsized and It is possible to significantly reduce the manufacturing cost.
Also, by making the nozzle tip smaller in diameter, even if the amount of combustion is reduced, the accumulation of fuel in the nozzle tip is reduced, so it is possible to use up to a small amount of combustion, from a large amount of combustion to a small amount of combustion. The combustion amount control range can be widened.

Further, by providing a step so that the nozzle projects downward from the oil feed pipe, it is possible to prevent fuel droplets from leaking along the oil feed pipe even if the amount of fuel accumulated at the tip of the nozzle increases. it can.

Further, by providing the inwardly protruding portion on the inner wall surface on the upstream side of the position corresponding to the nozzle of the primary air passage, even if the fuel drips into the primary air passage, the fuel leaks out at the protruding portion. Since it is blocked, the fuel can be prevented from leaking out of the primary air passage.

Furthermore, by integrally forming the protrusion so that the primary air passage protrudes inward, it is possible to prevent the fuel from leaking out and to prevent deformation by simple processing.

[Brief description of drawings]

FIG. 1 is a plan view of a liquid fuel combustion apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the nozzle portion.

FIG. 3 is a plan view of an essential part of a liquid fuel combustion apparatus according to a second embodiment of the present invention.

FIG. 4 is a plan view of an essential part of a liquid fuel combustion apparatus according to a third embodiment of the present invention.

FIG. 5 is a plan view of a conventional liquid fuel combustion device.

[Explanation of symbols]

 11 Burner Head 13 Vaporizer 15 Blower 16 Blower 17 Primary Air Passage 20 Nozzle 21 Oil Pipe 22 Electromagnetic Pump 24 Secondary Air Passage 25 Mixing Chamber 30 Spout Hole 31 Step 32 Protrusion

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Seiichi Shinoda 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A blower for supplying combustion air, a blower passage connected to the blower, a vaporizer for vaporizing liquid fuel, and a primary air in the blower duct and extending to the vaporizer inlet. A passage, a secondary air passage formed outside the primary air passage, a mixing chamber connected to the downstream side of the carburetor, a burner head formed on the downstream side of the mixing chamber, and a liquid fuel supply A pump, an oil feed pipe that conveys liquid fuel from the pump, and a tip end portion that is connected to the oil feed pipe in the primary air passage and has an inner surface and an outer surface that are on the same central axis and have a conical shape. A liquid fuel combustion apparatus having a plurality of ejection holes symmetrically with respect to a central axis on a conical surface and provided with a nozzle having a small tip portion. 2. The liquid fuel combustion apparatus according to claim 1, wherein a step is provided at a connecting portion between the oil feed pipe and the nozzle so that the lower end of the nozzle projects downward from the oil feed pipe. 3. The liquid fuel combustion apparatus according to claim 1, wherein an inwardly projecting portion is provided on an inner wall surface upstream of a position corresponding to the nozzle of the primary air passage. 4. The liquid fuel combustion apparatus according to claim 3, wherein the projection is integrally formed so as to project the primary air passage inward.