JP3258793B2 - Liquid fuel combustion device - Google Patents

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 for an oil fan heater or the like, and more particularly to a liquid fuel combustion apparatus having a flat ceramic burner head mounted on an opening of a vaporization cylinder.

[0002]

2. Description of the Related Art A conventional burner of this type in which a ceramic burner head is mounted on an opening of a vaporizing cylinder is disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 4-320708. This combustion device not only reduces the generation of nitrogen oxides, but also has superior heat resistance and durability compared to metal burner heads, and stabilizes the combustion state over a wide range from low calories to high calories. This has the advantage that the combustion width can be increased.

Further, a ceramic burner head formed in a flat shape is easy to mold and suitable for mass production.

[0004]

However, in the above-described liquid fuel combustion apparatus, since the burner head is made of ceramics having low pressure resistance, the burner head cannot be fixed directly with screws or the like when mounting the burner head. there were. Therefore, there is a need to provide a screw portion at the opening of the vaporizing cylinder, and to fix the burner head to the opening of the vaporizing cylinder by screwing an annular member to this screw portion. It was complicated. Further, since the burner head is made of ceramics having high heat insulating properties, there is a problem that sufficient heat back cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has as its object to provide a liquid fuel combustion apparatus capable of obtaining a sufficient heat back while simplifying a structure for mounting a ceramic burner head. And

[0006]

According to the present invention, there is provided a vaporizing cylinder for vaporizing a liquid fuel and mixing it with combustion air, and a plurality of flame holes which are attached to the opening of the vaporizing cylinder and eject gas to the outer peripheral portion. Is provided with a flat-plate-shaped ceramic burner head, and a flame spreader provided on the burner head and expanding a flame formed in a flame hole sideways or obliquely upward. A burner head fixing bracket for fixing the burner head to the opening of the vaporizing cylinder is provided integrally.

[0007]

In the above-described liquid fuel combustion apparatus, the mixed gas is ejected upward from each flame hole of the burner head, and the ejected mixed gas flows along the lower surface of the flame spreader provided on the burner head. It flows while changing its direction in the outer circumferential direction of the flame spreader. Therefore, the flame formed in the flame hole is spread horizontally or diagonally upward, and the leading end of the flame is mixed well with the surrounding air to be shortened, and the flame flows out of the combustion cylinder. This eliminates the worry of blowing out of the device. Therefore, even with a liquid fuel combustion device in which a flat ceramic burner head is mounted at the opening of the vaporization cylinder, a compact combustion cylinder with a low height can be used, and the diameter and height of the flame spreader can be increased. The amount of heat recovery can be adjusted by appropriately setting.

In addition, the flame spreader is directly heated by the combustion flame, and the flame spreader is integrally provided with a burner head fixing bracket for fixing the burner head to the opening of the vaporizing cylinder. Therefore, the heat of the flame spreader is transmitted to the vaporizing cylinder via the burner head fixing bracket, so that not only the heat recovery to the vaporizing cylinder is improved, but also it is not necessary to manufacture these parts individually. The number of points is reduced and the mounting structure is simplified.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 1 and 2, reference numeral 1 denotes a cylindrical vaporizing cylinder having a bottom and an open top, and the vaporizing cylinder 1 is made of aluminum die-cast. 2 is a sheath heater buried in the upper part of the peripheral wall of the vaporizing cylinder 1; 3 and 3 are a plurality of heat recovery projections formed integrally with the vaporizing cylinder 1 at the upper end of the vaporizing cylinder 1;
Is a primary air passage for supplying primary air for combustion into the vaporization cylinder 1, and the primary air passage 4 is in communication with a blower 5.
Reference numeral 6 denotes a burner case which is provided on the outer periphery of the vaporizing cylinder 1 and accommodates the vaporizing cylinder 1. Reference numeral 7 denotes a combustion cylinder which is provided upright on the burner case 6. Reference numeral 8 denotes an outside of the vaporizing cylinder 1 via the burner case 6. This is a secondary air passage for supplying combustion secondary air, and this secondary air passage 8 communicates with the blower 5 like the primary air passage 4.

Reference numeral 9 denotes an oil tank 1 utilizing a fuel pump 10.
A fuel nozzle for supplying liquid fuel (kerosene) 1 to the inside of the vaporizing cylinder 1; a throttle plate 12 disposed at an upper part in the vaporizing cylinder 1;
Reference numeral 3 denotes a ceramic burner head attached to the opening of the vaporizing cylinder 1. The burner head 13 is made of high-density low-expansion ceramics such as petalite which is resistant to heat shock and excellent in thermal shock resistance. The shape is a circular flat plate, and a large number of flame holes 1
4, 14... Are arranged in a plurality of rows in the circumferential direction, and
Each of these flame holes 14 is set to a hole diameter of about 1 to 2 mm.

As shown in detail in FIGS. 3 and 4,
Reference numeral 15 denotes a flame spreader mounted and fixed above the burner head 13 so as to cover the burner head 13. The flame spreader 15 is a circular flat plate portion 15A provided at the center, A flame expanding flange portion 15B enlarged diagonally outward from the portion 15A, a fixing ring (fixing metal) 15C for pressing and fixing the burner head 13 to the vaporizing cylinder 1 by screws 16, 16,. A plurality of support plates 15D, 1 hanging from the outer periphery of the flame flange 15B and connecting the flame expansion flange 15B and the fixing ring 15C.
5D, and are integrally formed of a heat-resistant steel plate. At this time, a plurality of heat transfer plates 15E, 15E,... Accommodating the heat recovery projections are provided on the outer periphery of the fixing ring 15C to increase the contact area with the vaporizing cylinder 1.

Reference numeral 16 denotes an ignition plug for igniting the mixed gas ejected from the flame hole 14, and reference numeral 17 denotes a flame sensor for detecting the flame F.

FIG. 2 is a cross-sectional view of an oil fan heater incorporating the liquid fuel combustion device having the above-described configuration. Reference numeral 18 denotes an outer casing of the oil fan heater, and 19 denotes a warm air provided on a front portion of the outer casing 18. A discharge port 20 is a blower for warm air provided on the back of the exterior body 18, and 21 is a blower duct for guiding the blow of the blower 20 for warm air to the discharge port 19 for warm air.

In the liquid fuel combustion apparatus having the above-described structure, when liquid fuel (kerosene) is ejected from the fuel nozzle 9 into the vaporizing cylinder 1, the liquid fuel passes through the ejection pressure of the fuel pump 10 and the primary air passage 4. It is atomized and scattered by the jet air flow from the blower 5 sent into the vaporizing cylinder 1 and scatters, and hits the inner wall of the vaporizing cylinder 1 which has been heated by the sheath heater 2 in advance, and is vaporized. The vaporized gas is mixed with air in the vaporizing cylinder 1, and the mixed gas flows through the passage of the throttle plate 12 to the burner head 13, and the flame holes 14, 1, and 1 of the burner head 13 are formed.
4, the gas is guided upward by the lower surface of the flame expanding flange 15 B of the flame expanding device 15, flows outward, and is injected from between the support plates 15 D, 15 D. Ignited to form a blue fire flame F to perform gasification combustion. At this time, the flame F is spread laterally or obliquely upward by the action of the flame spread plate 15, so that the heat recovery projections 3, 3 on the upper part of the vaporizing cylinder 1 are efficiently heated by the flame F during combustion. Since the heat of the heat recovery projections 3, 3 is transmitted to the vaporization cylinder 1, the vaporization cylinder 1 can be maintained at the temperature at which the liquid fuel can be vaporized even if the power supply to the heater 2 is stopped, and the combustion is continued. .

According to this embodiment, the flame spreader 15 is directly
In addition to being heated by the combustion flame, the flame spreader 15 is integrally provided with a fixing ring 15 </ b> C for fixing the burner head 13 to the opening of the vaporizing cylinder 1. Is transmitted to the vaporizing cylinder 1 via the fixing ring 15C, and the heat recovery to the vaporizing cylinder is improved.

The flat plate portion 15A, the flame spread flange 15
B, the fixing ring 15C, and the support plates 15D, 15D... Are integrally formed by heat-resistant steel plate as the flame spreader 15, so that it is not necessary to manufacture them individually, the number of parts can be reduced, and the mounting structure can be simplified. .

[0017]

Since the present invention is constructed as described above, the heat recovery amount can be reduced by appropriately setting the diameter and height of the flame spreader while taking advantage of the flat ceramic burner head. Can be adjusted, the flame spreader directly
In addition to being heated by the combustion flame, the heat of the flame spreader is transmitted to the vaporizing cylinder via the burner head fixing bracket, so that not only the heat recovery to the vaporizing cylinder is improved, but also the flame spreader and the burner head. Since the fixing bracket is integrally formed, there is no need to manufacture these parts individually, the number of parts is reduced, and the mounting structure of the ceramic burner head can be simplified.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a combustion apparatus showing one embodiment of the present invention.

FIG. 2 is a sectional view of an oil fan heater equipped with the combustion device.

FIG. 3 is a half sectional view of the flame spreader.

FIG. 4 is a plan view of the flame spreader.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vaporization cylinder 14 Flame hole 15 Flame spreader 15C Fixing ring (burner head fixing bracket) 16 Burner head

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-359704 (JP, A) JP-A-59-13818 (JP, A) JP-A-62-711 (JP, A) JP-A-55-138 51211 (JP, A) JP-A-4-320708 (JP, A) JP-A-5-141627 (JP, A) JP-A-55-100829 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23D 11/40 F23D 11/10

Claims (1)

(57) [Claims] 1. A flat plate-shaped ceramic having a vaporizing cylinder for vaporizing a liquid fuel and mixing it with combustion air, and being provided at an opening of the vaporizing cylinder and provided with a plurality of flame holes for ejecting gas on an outer peripheral portion thereof. A burner head, and a flame spreader provided on the burner head and expanding a flame formed in a flame hole sideways or obliquely upward. In this flame spreader, the burner head is provided with the vaporizer cylinder. A burner head fixing bracket for fixing the burner head to the opening is integrally provided.