JPH094924A - Warm air heater - Google Patents

Abstract

PURPOSE: To prevent a combustion cylinder from locally becoming red-hot and stably supply secondary air with a simplified structure. CONSTITUTION: This heater is provided with a body case 2 having a warm air blow-off outlet 4 and a fresh air suction inlet 6 and including a convection fan 7 for supplying fresh air sucked from the fresh air suction inlet to the warm air blow-off outlet mounted thereon, an air trunk 9 provided in the body case for guiding fresh air from the fresh air suction inlet to the warm water blow-off outlet, a combustion cylinder 22 at an upper opening provided in the air trunk, burner devices 11a to 11c provided on a lower part in the combustion cylinder, a heat shielding plate 30 provided between the combustion cylinder and the top of the air trunk. An opening 40 is provided in the heat shielding plate 30 for introducing fresh air to a front part of the combustion cylinder 22. Thereby, the opening in the heat shielding plate not only guides combustion gas in a direction where the warm air blow-off outlet is located but also introduces fresh air also to the front of the combustion cylinder so that the combustion cylinder can be cooled from the inside and outside thereof, and hence the combustion cylinder can be prevented from becoming red-hot and can be stably supplied also from an upper part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot air heater such as an oil fan heater and a gas fan heater.

[0002]

2. Description of the Related Art A vaporization type liquid fuel combustion apparatus conventionally used in this kind of hot air heater is, for example, Japanese Patent Publication No. 63-45.
Japanese Laid-Open Patent Publication No. 003 discloses a technique in which a ground plate is provided so as to prevent a metal combustion cylinder from being heated to a temperature higher than a heat resistant temperature while suppressing the spread of a flame formed laterally from a flame hole of a burner head. Japanese Patent Application Laid-Open No. 4-2781
Japanese Patent Laid-Open No. 07-2007 discloses a technique in which a plurality of heat recovery walls are provided on the upper surface of the vaporizing cylinder located between the earth plate and the burner head.

On the other hand, in Japanese Unexamined Patent Publication No. 4-324058, a downward airflow direction changing plate is provided on the lower surface of the top of the wind tunnel located on the warm air outlet side provided on the front surface of the heater to prevent secondary air flow. Disclosed is a liquid fuel combustion apparatus capable of stably supplying secondary air into the combustion chamber even when the supply port is blocked by dust or dirt.

[0004]

In the two former publications mentioned above, the ground plate directly blocks the spread of the flame toward the side, and the secondary air supplied to the periphery of the vaporizing portion is used as the flame. It guides upward from the outside and suppresses the flare spread of the flame by the air flow while stably supplying the combustion air, but if the flame blocking effect of this earth plate is too large, the flame is rather reduced. There was a problem that the desired combustion flame (fire power) could not be obtained. Also, the flame that grows during strong combustion increases the amount of the flame that hits the ground plate and increases the area that the flame touches, so the temperature of the ground plate becomes too high and it becomes red-heated. There were problems such as having to select an expensive material that was too burdensome, the ground plate itself was prone to deterioration, and the shape of only the portion facing the flame hole had to be changed.

Particularly, when the exclusive supply port or the suction port for the secondary air is blocked by dust or dust, the secondary air cannot be supplied around the earth plate, and the fuel cannot be completely burned to cause unburned fuel. There was a problem that a large amount of gas was generated or the flame could not be prevented from spreading to the side, and the combustion cylinder could not be suppressed from becoming red heat. In addition, the flame that comes out of the flame holes to the outside during weak combustion does not reach the ground plate, and the ground plate acts as a barrier to the air supply, and secondary air cannot be supplied near the flame, which also tends to result in incomplete combustion. .

On the other hand, in the latter publication, the combustion gas generated in the combustion tube is guided upward and comes into direct or indirect (radiation) contact with the wind tunnel. Temperature is too high,
There is a danger that the parts above the wind tunnel will be thermally damaged and that the user will be at risk due to heat conduction to the main body that is connected to the wind tunnel. There is a problem that soot is easily attached to the lower surface of the body, soot attached to the lower surface of the wind tunnel is guided toward the outlet of the heater by the cool air from the blower, and soot is blown out from the outlet together with the warm air. Further, only by guiding the secondary air to the combustion cylinder from above and below, it is not possible to prevent the flame from spreading laterally, and as a result it is not possible to prevent the flame from touching the combustion cylinder. It is not possible to reliably suppress red heat in the combustion cylinder.

Particularly in both technologies, in the lead-out portion of the heater for heating the burner body, the secondary air flowing upward from the outside of the burner body is obstructed by the lead-in portion, and only at the place where the lead-in portion is located. Since it cannot be passed through, at least the spread of the flame above this part cannot be pushed back inward by the secondary air, and only a part of the combustion cylinder located outside the upper part of the heater lead-out part is easily red-heated. There was also.

It is therefore an object of the present invention to provide a warm air heater capable of suppressing local red heat of the combustion cylinder with a simple structure and stably supplying secondary air.

[0009]

The hot air heater according to claim 1 of the present invention has an outside air inlet and a warm air outlet, and supplies outside air sucked from the outside air inlet to the warm air outlet to the rear surface. A main body case to which a convection blower is attached, a wind tunnel provided in the main body case for guiding the outside air from the outside air intake port to the warm air outlet, a combustion cylinder with an upper opening provided in the wind tunnel, and this combustion A burner device provided in the lower part of the cylinder,
A heat shield provided between the combustion cylinder and the top of the wind tunnel, and the heat shield further has an opening for introducing outside air at the front of the combustion cylinder. It is a thing.

According to a second aspect of the present invention, in the warm air heater, a front slant portion is provided at a front portion of the heat shield plate to sequentially guide outside air obliquely downward, and the wind tunnel and the heat shield plate are provided at the front slant portion. And an opening for introducing the air flowing between and into the combustion cylinder.

Further, in this heater, a rear slant portion for guiding the outside air sequentially upward and a hanging piece portion further downwardly hanging from the rear slant portion are provided at the rear portion of the heat shield plate.
An opening for introducing outside air to the lower surface of the heat shield plate is provided in the rear inclined portion.

[0012]

According to the first aspect of the present invention, the opening provided in the heat shield is not only used as a guide port for guiding the combustion gas forward (the direction in which the hot air outlet is located), but also in the front portion of the combustion tube. Since it acts as an introduction part for introducing the outside air, it can guide the cooling air for cooling the combustion cylinder from the inner surface and the cooling air for cooling the combustion cylinder from the outer surface, suppressing the red heat of the combustion cylinder and raising the combustion secondary air upward. Stable supply from.

According to the second aspect of the present invention, the opening formed in the front part of the heat shield plate, which is formed in the front inclined part for sequentially guiding the outside air obliquely downward, flows between the wind tunnel and the heat shield plate. Since it acts as an air introduction part that introduces a part of the air into the combustion cylinder,
The combustion tube is cooled from the inner surface by part of the air flowing between the wind tunnel and the heat shield, and the spread of the flame to the side is also suppressed, and the red heat in the front part of the combustion tube is suppressed more effectively. It

According to the third aspect of the present invention, the opening provided in the rear portion of the heat shield plate and formed in the rear inclined portion for sequentially guiding the outside air upward serves as an inlet for introducing the outside air into the lower surface of the heat shield plate. Therefore, in addition to the effect of the second aspect of the invention, cooling of the lower surface of the heat shield plate is promoted, and the upper portion of the combustion gas is easily restrained obliquely forward and downward.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side sectional view showing an embodiment of the whole structure of the warm air heater of the present invention, FIG. 2 is an enlarged side sectional view of the upper portion of FIG. 1, and FIG. 3 is a heat shield plate of the present invention. FIG. 4 is a perspective view showing one embodiment from a diagonally lower rear side, FIG. 4 is a perspective view showing another embodiment of the heat shield of the present invention seen from a diagonal lower rear side, and FIG. 5 is one embodiment of the burner device of the present invention. FIG. 6 is a perspective view showing an example, and FIG. 6 is a perspective view showing an embodiment of the vaporizing cylinder of the present invention.

In FIGS. 1 and 2, reference numeral 1 denotes a warm air heater (hereinafter referred to as a heater) represented by an oil fan heater. The heater 1 has an upper surface 2A, a front surface 2B, a rear surface 2C, and left and right side surfaces 2D. , 2E, which is made of metal, and
It is composed of a thick metal base 3 that closes the lower surface opening of the main body case 2.

A warm air outlet 4 is formed in the substantially central portion of the front surface of the main body case 2, and a round air inlet port 5 which doubles as an air intake and a bell mouth of a fan 7C described later is formed on the rear surface of the main body case. Is formed, and in the peripheral portion of the air inlet 5,
A fan guard 8 made of metal and having a plurality of outside air suction ports 6 formed in a mesh shape and a convection blower 7 also serving as a filter is attached. The convection blower 7 has a rotating shaft 7A.
And a fan 7C attached to the rotating shaft 7A.

In the main body case 2, one end communicates with the hot air outlet 4 and the other end communicates with the upper side of the air inlet 5 (specifically, the fan 7C portion of the convection blower 7) so that the outside air A wind tunnel 9 made of metal is arranged to guide the outside air sucked from the suction port 6 to the warm air outlet 4. The arrows in the figure indicate the flow of air.

Reference numeral 11 denotes a burner device arranged in the lower part of the main body case 2 for vaporizing and burning petroleum fuel. The burner device 11 includes a vaporizing cylinder 11A made of a bottomed cylindrical aluminum alloy and the vaporizing cylinder. The burner head 11B is mounted on the upper portion of 11A and has a plurality of flame holes 11b on its side surface, and a burner case 11C that surrounds the vaporization cylinder 11A (see FIG. 5 for details).

Reference numeral 12 denotes a combustion blower that supplies combustion primary air (hereinafter referred to as primary air) into the vaporization cylinder 11A and also supplies combustion secondary air (hereinafter referred to as secondary air) into the burner case 11C. Yes, combustion blower 12
Is a motor 12B having a rotating shaft 12A, and a motor 12B
Fan 12C attached to the rotary shaft 12A of the
The photo sensor 12D includes a light emitting unit for detecting the rotation speed of 2A and a light receiving unit.

The suction duct 13 of the combustion blower 12 extends to the outside of the rear surface 2C of the main body case 2, and the filter 1 is attached to the suction port (tip of the suction duct) 13A.
4 are provided. The position of the suction port 13A is not limited to the rear surface 2C of the main body case, and may be the left and right side surfaces.

Reference numeral 15 is a combustion primary air supply path for supplying primary air to the vaporizing cylinder 11A, and 16 is a combustion secondary air supply path for supplying secondary air into the burner case 11C. Reference numeral 17 denotes a nozzle that is provided so as to penetrate through the primary combustion air supply passage 15 and serves as a fuel supply device that supplies liquid fuel to the vaporization cylinder 11A. Reference numeral 18 is a burner ring, 19 is a plurality of heat recovery projections provided on the upper surface of the vaporization cylinder 12A so as to face the flame holes 11b of the burner head 11B,
Reference numeral 20 is a flame sensor, and 21 is a spark plug. still,
The heat recovery projections 19 do not have to correspond one-to-one to the flame holes 11b. Reference numeral 22 denotes a metal upper opening combustion cylinder provided in the wind tunnel 9, and the combustion cylinder 22 is the burner device. It is provided upright on the bottom surface of the wind tunnel 9 so as to cover the periphery of the upper part of 11 (particularly the burner case 11C), and the combustion gas generated in the burner device 11 is made to flow out from the opening 22B in the upper part. The propeller fan 7C of the convection blower 7 is arranged so as to face the combustion cylinder 22, and the height of the cylinder 22 is approximately the same as the height of the upper surface of the motor 7B as shown in FIG.

Reference numeral 23 is a viewing window provided on the front surface of the combustion cylinder 22 for flame monitoring. The peep window 23 is configured by fixing a transparent mica plate 23A as a peek transparent member to a front outer surface of the combustion tube 22 by a fixture 23B so as to be in close contact therewith. The transparent member for peep of the peep window 23 is preferably one having heat resistance and sufficient strength, for example, the mica plate 2
It is possible to use a thin glass plate instead of 3A,
It is not suitable because it is easily damaged by flames and heat of combustion gas. If the mica plate 23A is not adhered and fixed to the outer surface of the combustion cylinder 22, hot air or combustion gas inside the combustion cylinder 22 leaks out through the gap and carbon monoxide is generated. Therefore, it is important to fix the mica plate 23A in close contact.

In FIG. 1, F shows the outline of the flame that can be seen in normal combustion in the strong combustion state, and FX shows the outline of the actual flame, which is also not visible.

Reference numeral 30 is a heat shield plate made of an aluminum-plated steel plate provided between the combustion cylinder 22 and the top surface 9A of the wind tunnel 9. As shown in FIG. 3, the heat shield plate 30 has a top surface 9A of the wind tunnel 9.
The front surface 31 and the front portion and the rear portion thereof are respectively bent obliquely downward to form a steeply inclined front inclined portion 32 and a gently inclined rear inclined portion 33, and from the lower end of the front inclined portion 32. A front hanging piece 34 extending further downward and extending to a position overlapping the front portion of the combustion cylinder 22, and a rear inclined portion 33.
A rear hanging piece 35 is formed that hangs further downward from the lower end of the above and extends above the combustion cylinder 22.

On both right and left sides of the top surface 31 of the heat shield plate 30,
The side pieces 36, 36 are bent downward at right angles.
Are formed on the rear side of the side piece portions 36, 36, and rear fixing piece portions 37, 37 are formed as first fixing portions, which extend laterally and whose front ends are bent downward. Front fixing pieces 38, 38 as second fixing portions having claws and screw holes for fixing the heat shield plate 30 to the side wall of the wind tunnel 9 are formed at both ends of the front hanging piece 34. Pieces 37 and 38
Is inserted into holes (not shown) formed in the side wall and the front wall of the wind tunnel 9 to be temporarily fixed, and each fixing piece is finally fixed by spot welding.

Further, the rear hanging piece 35 formed at the rear edge of the gently inclined rear inclined portion 33 has a right side portion 39 in the relationship between the rotation direction of the propeller fan 7C and the wind flow, as shown by the broken line in FIG. Is cut out.

Reference numeral 40 denotes a combustion cylinder 22 formed on the front inclined portion.
Is a front hole as an opening for introducing the outside air into the front part of, and in the present embodiment, the center in the width direction is formed in a square shape with a width of 66 mm and a height of 16 mm so as to match the center position of the combustion cylinder 22. However, the shape and the center position in the width direction are not particularly limited to this example, and may be elliptical or semicircular at both ends. Further, 41 is a rear hole formed in the rear inclined portion 33 as an opening for introducing outside air for introducing outside air toward the lower surface of the top surface 31 of the heat shield plate 30 and the front portion of the combustion cylinder 22,
In this embodiment, only the both ends are formed in semicircular long holes (width 80 mm, height 15 mm), but the shape is not limited to this example, and shapes such as circle, ellipse, quadrangle and triangle are possible. Anything is fine.

The solid line arrow in FIG. 2 shows the outline of the air flow during combustion, and the one-dot chain line arrow shows these openings 40 and 41.
The outline of the flow of the air introduced from is shown.

Here, an opening 40 formed in the front inclined portion 32 which is provided in the front portion of the heat shield plate 30 and guides the outside air in a diagonally downward direction has an air flow between the wind tunnel 9 and the heat shield plate 30. Since it acts as an air introduction part for introducing a part of the air into the combustion cylinder 22, the air (outside air) flowing between the wind tunnel 9 and the heat shield plate 33.
It was possible to positively guide a part of the gas to the front part of the combustion cylinder 22, to cool the combustion cylinder 22 from the inner surface, and to effectively suppress the flare F from spreading laterally. . In particular, it was possible to prevent and prevent the red heat phenomenon of the combustion cylinder 22, which was apt to occur when the flame hits the front portion of the combustion cylinder 22 (particularly the peripheral portion of the viewing window 23) for a long time.

Further, an opening 41 formed in the rear inclined portion 33 provided in the rear portion of the heat shield plate 30 for sequentially guiding the outside air upward.
However, since it acts as an inlet for introducing outside air into the lower surface of the top surface 31 of the heat shield plate 30, cooling of the lower surface of the heat shield plate 30 can be promoted, and the upper portion of the combustion gas can be pushed diagonally forward and downward. It was possible to suppress the thermal influence on the heat shield plate 30.

Moreover, the secondary air can be supplied into the combustion cylinder 22 from above by the openings 40 and 41.
Therefore, the secondary air can be supplied from both the upper and lower directions.

In the above structure, for example, the combustion cylinder 22
L1 between the end of the upper surface opening 22B and the lower end of the rear hanging piece 35
Is about 8 mm, and the distance L2 between the end of the upper opening 22B of the combustion cylinder 22 and the extension line of the rotating shaft 7A of the convection blower 7 is about 14 m.
By setting the distance L3 between the end of the upper surface opening 22B of the combustion cylinder 22 and the heat shield plate 30 to about 20 mm, the ratio of each distance, that is, L1: L2: L3 = 1: about 1.75: about 2.5. Become.
The distance L4 between the lower end of the front hanging piece 34 of the wind tunnel 9 and the end of the upper surface opening 22B of the combustion tube 22 is about 33 mm, the inner diameter of the combustion tube 22 is about 140 mm, and the convection blower 7 rotates from the bottom of the wind tunnel 9. The height h1 to the extension of the shaft 7A is 120 mm, and the height h2 from the bottom of the wind tunnel 9 to the top 9A of the wind tunnel 9 is 204.
mm.

On the other hand, although another embodiment of the heat shield plate is shown in FIG. 4, the same reference numerals as those of the heat shield plate 30 shown in FIG. 3 have the same configuration and function. Reference numeral 50 is another heat shield plate, and 51 is an opening formed by a cut and raised piece 52 formed by cutting and raising a part of the front portion of the top surface 31 in the width direction.

By tilting the cut-and-raised piece 52 obliquely rearward, a part of the air flowing between the top portion 9A of the wind tunnel 9 and the top surface 31 of the heat shield plate 50 is forced to flow downward. In addition, the outside air is guided from the opening 51 to the lower side of the heat shield plate 50, especially to the inner surface of the front portion of the combustion tube 22 through the opening 51.

By forming this opening 51, not only can the combustion gas generated during combustion be guided forward (specifically, the direction in which the hot air outlet 4 is located), but also the front portion of the combustion cylinder 22 can be guided. Since the outside air can be introduced, the cooling air that cools the combustion cylinder 22 from the inner surface and the cooling air that cools the combustion cylinder 22 from the outer surface can be efficiently guided from the upper side to the lower side. It was possible to suppress and prevent the red-hot phenomenon of (part) and to stably supply the secondary air for combustion from above the combustion cylinder 22.

In the above structure, the combustion gas (see FX in FIG. 1) generated by the combustion of the burner device 11 rises in the combustion cylinder 22, passes through the upper opening 22B of the combustion cylinder 22, and the heat shield plate 30.
The air is discharged inside and mixed with the outside air sent from the convection blower 7 provided on the rear surface of the main body case 2, becomes warm air and is blown out from the warm air outlet 4 to heat the room.

By the air sent from the convection blower 7,
It is possible to suppress the temperature rise of the rotating shaft 7A, and it is possible to prevent the lubricating oil of the bearing portion from being evaporated or hardened due to the temperature rise as in the conventional case, thereby preventing the rotating shaft 9 from rotating smoothly. Further, the rear inclined portion 33 and the rear hanging piece 35 allow the air sent from the convection blower 7 to flow between the upper surface opening 22A of the combustion cylinder 22 and the heat shield plate 30, and between the heat shield plate 30 and the top of the wind tunnel 9. Since it can be appropriately distributed to and from 9A, combustion can be stabilized and the main body case 2 can be efficiently prevented from overheating.

By the way, if a filter (not shown) provided at the suction port 13A of the suction duct 13 of the combustion blower 12 is clogged or is clogged by a curtain or the like, it is burned into the vaporizing cylinder 11A. Since the supply amount of the primary air decreases and the supply amount of the secondary air for combustion into the burner case 11C decreases, the supply air becomes insufficient. At this time, the flame F formed in the flame hole 11b of the burner head 11B is in a red fire state due to lack of oxygen, and not only the temperature of the flame is lowered but also the temperature of the combustion gas is lowered, and the outer shape of the flame is also normal. Since it reaches a position higher than the outer shape FX during combustion, the heat shield plate 30 is likely to be directly heated by the flame. Moreover, when oxygen is insufficient, the amount of carbon monoxide emitted increases due to the generation of unburned gas.

In this embodiment, the air blown from the convection blower 7 is caused by the rear hole 41 of the rear inclined portion 33, the notch 39 of the rear hanging piece 35, and the gap between the rear hanging piece 35 and the upper end 22B of the combustion tube 22. Is partially introduced into the space between the upper surface opening 22B of the combustion cylinder 22 and the heat shield plate 30, the upper surface opening 2
External air (fresh air) is supplied to the flame FX protruding from 2B at a substantially right angle, and the combustion of the flame FX is promoted by the fresh air to shorten the flame, and a flame may be emitted from the hot air outlet 4. It will disappear. Also, flame F
Since the combustion of carbon monoxide in X is promoted to carbon dioxide, the generation of carbon monoxide can also be reduced.

Further, in the above embodiment, since each part of the heat shield plate 30 or 50 is integrally formed by bending, the number of parts can be reduced and the structure can be simplified.

FIG. 5 is an explanatory view showing an enlarged main part of the burner device 11 which can be preferably used in the present invention. The burner device 11 includes the vaporizing cylinder 11A and the vaporizing cylinder 1 as described above.
The burner head 11B mounted on the upper part of 1A and the burner head 11B provided on the outer periphery of the burner head 11B.
Burner ring 61 having a comb-shaped annular wall facing a plurality of slits S from the upper end toward the root, and the flame hole 11b of the burner head 11B.
An ignition plug 21 for igniting a mixture of petroleum fuel and primary air ejected from the flame and a flame sensor 20 are provided. The insulators of the ignition plug 21 and flame sensor 20 are connected to the comb-shaped annular wall (that is, burner). The insulator 61 is provided on the outside of the ring 61), and the comb-shaped annular wall has no slit S at a portion facing the insulator portion of the spark plug 21 and the frame sensor 20 or an insulator protection portion having a slit shallower than other portions. 6
This is a configuration in which 1P and 61Q are formed.

Reference numeral 62 designates the vaporizing cylinder 11A at a predetermined temperature (for example, 2
It is a sheathing heater for heating as a vaporization heater that heats up to 50 ° C. or more, is arranged in a substantially annular shape inside and above the vaporization cylinder 11A, and is led out from one place. This heater 6
The derivation part of 2 is called the derivation part 62A, and the burner ring 61
In the portion of the heater facing the lead-out portion 62A, there is formed a protection portion 61R having no slit S or having a shallower slit than the other portions.

With this structure, the flame formed in the flame hole 11b becomes small during weak combustion, and the secondary air flows into the inside of the burner ring 61 from the slit S of the comb-shaped annular wall. The combustion reaction of the flame is promoted by the secondary air flowing into the inside of the ring 61, and good weak combustion with a small amount of carbon monoxide generated can be performed. Further, at the time of strong combustion, the flame formed in the flame hole 11b becomes large, and the heat of this flame is taken away by the comb-teeth annular wall and the heat recovery projection 19, so that the flame temperature can be lowered and NOX The amount generated decreased.

Further, since the burner ring 61 is provided with insulator protection portions 61P and 61Q at the portions facing the respective insulator portions of the spark plug 21 and the frame sensor 20, the insulator protection portions 61P and 61Q receive flames. At the same time, the flow of flame can be directed upward while preventing the flame from spreading to the side, and it is possible to prevent the temperature of the spark plug 21 and the insulator portion of the frame sensor 20 from rising above the heat resistant temperature. It was possible to reliably prevent the occurrence of heat damage to the spark plug 21 and the flame sensor 20 with a simple configuration.

Further, since the protective portion 61R having no slit S is formed in the portion of the burner ring 61 facing the lead-out portion 62A of the heater, the flow of the secondary air guided upward from below by the presence of the lead-out portion 62A. Even if the so-called air curtain effect that pushes back the flame inward is disturbed locally, this protective portion 61R catches the flame and prevents the flame from spreading to the side while directing the flow of the flame upward. It was possible to prevent the red heat phenomenon that was likely to occur in the portion of the combustion cylinder 22 located near the lead-out portion 62A of the heater. FIG. 6 is a vaporization cylinder 11 of a burner device 11 which can be preferably used in the present invention.
It is an enlarged view of the principal part of A. A plurality (six in this embodiment) of heat recovery is provided at the upper end of the bottomed cylindrical vaporization cylinder 11A into which liquid fuel and primary air for combustion are supplied, facing the flame holes 11b of the burner head 11B. This is a configuration in which the protrusion 19 is provided. Reference numeral 62 is the above-mentioned sheath heater for heating.

According to this structure, the flame becomes small at the time of weak combustion and approaches the flame hole 11b of the burner head 11B, but the burner head 11B and the vaporizing cylinder 11A.
The upper end of each is sufficiently heated by the flame in the flame contact state by the heat recovery projections 19, and the vaporization section (inside the vaporization cylinder) has a temperature suitable for vaporization of the liquid fuel (for example, 330 ° C. to 370 ° C.).
Can be maintained at a high level). On the other hand, at the time of strong combustion, the flame becomes large and the high temperature part of the flame separates from the flame hole 11b, but a plurality of (6 in the embodiment) heat recovery projections 19 provided at the upper end of the vaporization cylinder 11A Of the heat recovery projection 19 that is wrapped in the high temperature part of the
Since the heat of can be transferred to the bottom of the vaporization cylinder 11A,
The amount of heat recovery at the time of strong combustion can be dramatically increased.

As shown in FIG. 6, each of the heat recovery projections 19 has a columnar shape and has a diameter of about 6 to 8 mm.
In addition, the height is set to about 8 to 10 mm, and the upper ends of the annular vaporization cylinders 11A are provided at substantially equal intervals (for example, large intervals of about 25 to 35 mm) in the circumferential direction. Further, it is formed by integral molding with the vaporizing cylinder 11A.

As described above, the range of temperature change of the vaporization cylinder 11A can be reduced in a wide range from strong combustion to weak combustion, and combustion depending on the vaporization state of fuel is stable over a wide range from strong combustion to weak combustion. However, the flame current can be stabilized, the amount of carbon monoxide generated can be reduced, and the nitrogen temperature can be reduced due to the decrease in flame temperature due to the heat recovery action of the heat recovery projections 19, thereby greatly expanding the combustion range. be able to.

[0051]

According to the invention of claim 1, the opening provided in the heat shield plate allows the combustion gas to flow forward (the direction in which the hot air outlet is located).
It not only acts as a guide port for guiding the air to the combustion cylinder, but also acts as an introduction part for introducing outside air to the front part of the combustion cylinder, so that both cooling air for cooling the combustion cylinder from the inner surface and cooling air for cooling the combustion cylinder from the outer surface are both It is possible to guide and prevent the red heat of the combustion cylinder from being suppressed and to stably supply the secondary combustion air from above.

According to the second aspect of the present invention, the air flowing between the wind tunnel and the heat shield plate is provided with an opening formed in the front portion of the heat shield plate, which is formed in the front slope portion for guiding the outside air in a diagonally downward direction. Part of the air acts as an air introduction part that is introduced into the combustion cylinder, so that part of the air flowing between the wind tunnel and the heat shield can be positively guided to the front part of the combustion cylinder. It is possible to cool the cylinder from the inner surface, suppress the spread of the flame to the side, and more effectively suppress the red heat of the front portion of the combustion cylinder.

According to the third aspect of the present invention, the opening provided in the rear portion of the heat shield plate and formed in the rear inclined portion for sequentially guiding the outside air upward serves as an inlet for introducing the outside air into the lower surface of the heat shield plate. In addition to the effect of the invention of claim 2, cooling of the lower surface of the heat shield plate can be promoted, and the upper portion of the combustion gas can be pushed obliquely forward and downward, so that the thermal influence on the heat shield plate can be suppressed.

[Brief description of drawings]

FIG. 1 is a side cross-sectional view showing an example of the overall configuration of a warm air heater according to the present invention.

FIG. 2 is an enlarged side sectional view of an upper portion of FIG.

FIG. 3 is a perspective view showing an embodiment of a heat shield plate of the present invention as seen obliquely from below and from the rear.

FIG. 4 is a perspective view showing another embodiment of the heat shield plate of the present invention as seen obliquely from below and from the rear.

FIG. 5 is a perspective view showing an embodiment of the burner device of the present invention.

FIG. 6 is a perspective view showing an embodiment of a vaporization cylinder (burner body) of the present invention.

[Explanation of symbols]

 1 Oil fan heater (warm air heater) 2 Main body case 4 Warm air outlet 6 Outside air suction port 7 Convection blower 9 Wind tunnel 11 Burner device 22 Combustion cylinder 22B Top opening 30 Heat shield (first embodiment) 31 Top surface 32 front inclined part 33 rear inclined part 40 front hole (opening) 41 rear hole (opening) 50 heat shield plate (second embodiment) 51 opening 52 cut and raised piece

Claims (3)

[Claims] 1. A main body case having an outside air suction port and a warm air outlet, and a rear surface of which is provided with a convection blower for supplying the outside air sucked from the outside air inlet to the warm air outlet, and a main body case provided in the main body case. A wind tunnel for guiding the outside air from the outside air intake port to the warm air outlet, a combustion cylinder with an upper opening provided in the wind tunnel, a burner device provided in the lower part of the combustion cylinder, the combustion cylinder and the wind. In a warm air heater provided with a heat shield provided between the top of the body and the heat shield, the heat shield is provided with an opening for introducing outside air in the front part of the combustion cylinder. heater. 2. A main body case having an outside air intake port and a warm air outlet and having a convection blower for supplying the outside air sucked from the outside air inlet port to the warm air outlet on the rear surface thereof, and provided in the main body case. A wind tunnel for guiding the outside air from the outside air intake port to the warm air outlet, a combustion cylinder with an upper opening provided in the wind tunnel, and a burner device provided in the lower part of the combustion cylinder.
In a warm air heater having a heat shield provided between the combustion cylinder and the top of the wind tunnel, a front sloped portion that sequentially guides outside air obliquely downward is provided at the front of the heat shield. The warm air heater, wherein an opening for introducing the air flowing between the wind tunnel and the heat shield into the combustion cylinder is provided in the front inclined portion. 3. The rear portion of the heat shield plate is provided with a rear slant portion for guiding the outside air sequentially upward, and a hanging piece portion hanging further downward from the rear slant portion. The hot-air heater according to claim 2, further comprising an opening for introducing a heat sink into the lower surface of the heat shield plate.