JP2812062B2 - Heating 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 heat generating apparatus used for irons, steamers, cookers, coffee makers, etc., which burns gaseous or liquid fuel and uses the heat of combustion as a heat source.

[0002]

2. Description of the Related Art Conventionally, there are cordless hair curlers, hand warmers and the like as heat generating devices using heat of combustion as a heat source. These fuels use butane gas or benzene as fuel, evaporate the fuel and mix it with air, then contact the mixed gas with a felt-like catalyst carrying a platinum catalyst to cause a catalytic reaction and reduce the heat of combustion. To use.

[0003]

The above combustor has a small amount of combustion and the combustion proceeds in a state where the temperature of the catalyst is low. However, if the amount of combustion is increased to increase the calorific value, the amount of mixed gas to be reacted in the catalyst layer increases,
The mixed gas cannot be completely reacted in the catalyst layer, and is discharged unburned. Therefore, in order to increase the amount of combustion, the area where the mixed gas comes into contact with the catalyst layer must be increased, causing a problem that the size of the combustor increases.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a compact heat generating device having a small combustion chamber.

[0005]

According to the present invention, there is provided a fuel gas and air mixing section, and a housing provided downstream of the mixing section and having a combustion chamber therein. The fins are provided substantially in parallel, and the catalyst layer is brought into close contact with the wall surfaces of the combustion chamber and the outer wall surfaces of the fins.

Further, a gap is provided between a fin tip in the combustion chamber and a wall surface of the combustion chamber.

[0007]

[Function] Catalytic combustion means that when a mixed gas of fuel and air is supplied to the surface of the catalyst layer which has been heated to the activation temperature in advance, the catalyst works near the surface of the catalyst layer and the temperature is lower than that of flame combustion. This is a combustion phenomenon in which the mixed gas burns to generate an exothermic reaction. Therefore, in order to increase the combustion rate in catalytic combustion, it is important how to efficiently supply the mixed gas to the catalyst surface. The present invention has been made in view of the above.

In the present invention, the fin is provided in the combustion chamber, and the catalyst layer is brought into close contact with the outer wall surface of the fin, thereby increasing the catalyst area without changing the size of the combustion chamber. Moreover, by providing the fins in the combustion chamber, not only the catalyst area but also the heat transfer area increases, so that the heat exchange efficiency for heating the object to be heated by the combustion heat on the catalyst surface is remarkably improved. Therefore, the size of the combustion chamber can be made very small.

In such catalytic combustion, surface combustion occurs on the surface of the catalyst, so that the combustion temperature on the catalyst surface has a great influence on the combustion characteristics. On the other hand, since the outer wall surface of the combustion chamber supplies heat to the object to be heated as a hot plate, the combustion temperature of the catalyst surface may fluctuate due to a change in the amount of heating to the object to be heated. In the present invention, not only the inner wall surface of the combustion chamber, but also the heat of combustion on the catalyst surface in close contact with the outer wall surface of the fins is transmitted through the fins, conducted to the outer wall surface of the combustion chamber, and contributes to heating of the object to be heated. . Since the catalyst layer in close contact with the outer wall surface of the fin is not in direct contact with the heating surface, it is difficult to receive a change in the heating amount of the heating surface,
The combustion temperature on the catalyst surface is maintained at a high temperature, and stable combustion can be performed. In addition, since combustion heat is supplied as radiation from the surface of the catalyst layer burning at high temperature to the combustion chamber wall surface, fluctuations in the combustion temperature of the catalyst layer on the wall surface of the combustion chamber caused by fluctuations in the heating amount of the object to be heated are prevented. can do.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a sectional view of an embodiment of the present invention. FIG. 2 is a view in the direction of arrows AA in FIG. In FIG. 1, reference numeral 1 denotes a liquefied gas cylinder such as propane or butane. A valve 3 is provided between the cylinder 1 and the nozzle 2,
The flow rate of the fuel gas supplied from the cylinder 1 can be controlled. The fuel gas ejected from the nozzle 2 sucks the surrounding air by the attraction of the gas flow, is uniformly mixed in the mixing chamber 4, and is supplied to the combustion chamber 5. Combustion chamber 5
Is provided inside the heat generating section 6 which is formed of a metal housing. Fins 7 are provided in the combustion chamber 5 in a direction substantially parallel to the flow direction of the mixed gas. By increasing the heat transfer area, the heat exchange efficiency of combustion heat on the catalyst surface can be improved.

In the combustion chamber 5, a catalyst layer 8 is provided in close contact with the wall surface of the combustion chamber. A thin platinum wire ignition heater 9 is heated by a dry battery (not shown), and a catalyst layer 8 which is closer to the platinum wire is heated.
Temperature rises. When the catalyst layer 8 is heated to the activation temperature, the valve 3 is opened and the combustion gas is
Supplied to The operation at this time may be performed by monitoring the temperature in the combustion chamber 5, or the valve 3 may be opened after a certain period of time has elapsed after the ignition heater 9 is energized. The air and the fuel gas, which are attracted to the injection power of the fuel gas and mixed, are mixed in the mixing section 4, and the mixed gas is supplied to the combustion chamber 5. In the combustion chamber 5, when the mixed gas of fuel and air is supplied to the surface of the catalyst layer 8 heated to the activation temperature, the mixed gas starts burning on the surface of the catalyst layer 8. Near the inlet of the combustion chamber 5, only the mixed gas supplied near the wall of the combustion chamber burns near the catalyst layer 8, but the mixed gas near the center of the combustion chamber 5 passes through the combustion chamber 5 unburned. Will pass. Therefore, as for the gas passing through the combustion chamber 5, the combustion gas flows near the wall surface, and the mixed gas flows inside the combustion gas.

Fins 7 are provided in the combustion chamber 5 substantially parallel to the flow direction of the mixed gas, and a catalyst layer 10
Is in close contact. Therefore, the mixed gas collides with the combustion surface 10a of the fin 7, and a part of the unburned gas in the mixed gas burns on the combustion surface 10a. The combustion gas burned near the combustion surface 10a and the inlet of the combustion chamber 5 and the unburned fuel gas are mixed,
The fuel flows between the catalyst layer 10 closely attached to the fins 7 and the catalyst layer 8 closely attached to the inner wall surface of the combustion chamber 5. At this time, since the high-temperature combustion gas and the unburned fuel gas are mixed, there is an effect of increasing the temperature of the fuel gas. When the high-temperature fuel gas flows through the narrow gap between the catalyst layer 8 and the catalyst layer 10, all of the unburned combustion gas is burned. Catalyst layer 8
If the gap between the catalyst layer and the catalyst layer 10 is too wide, the effect is lost. As a result of an experiment in which a fibrous porous material was bonded to a combustion chamber made of aluminum, it was confirmed that the effect was large when the gap between the catalyst layers 8 and 10 was 4 mm or less.

Further, since the combustion gas flows through the narrow gap between the catalyst layer 8 and the catalyst layer 10, the flow velocity of the combustion gas increases, the heat transfer coefficient on the combustion gas side increases, and Improve exchange efficiency.

[0015] Since catalytic combustion involves surface combustion on the surface of the catalyst, the combustion temperature on the catalyst surface has a significant effect on combustion characteristics. On the other hand, since the outer wall surface of the combustion chamber 5 supplies heat to the object to be heated as the heat generating portion 6, the combustion temperature of the catalyst surface 8 may fluctuate due to a change in the amount of heat applied to the object to be heated. According to the present invention, not only the inner wall surface of the combustion chamber 5 but also the heat of combustion on the surface of the catalyst layer 10 adhered to the outer wall surface of the fin 7 is transmitted through the fin 7 and transmitted to the heat generating portion 6 on the outer wall surface of the combustion chamber 5. Contributes to the heating of the object to be heated. Since the catalyst layer 10 in close contact with the outer wall surface of the fin 7 is not in direct contact with the heat generating portion 6, the catalyst layer 10 is hardly affected by a change in the heating amount of the heat generating portion 6, and the combustion temperature on the catalyst layer surface is maintained at a high temperature. , And stable combustion can be performed. Moreover, the catalyst layer 1 burning at high temperature
Since combustion heat is supplied as radiation from the surface 0 to the catalyst layer 8 on the wall surface of the combustion chamber, it is possible to prevent fluctuations in the combustion temperature of the catalyst layer 8 on the wall surface of the combustion chamber caused by fluctuations in the amount of heating of the object to be heated. .

The combustion gas cleanly burned in the combustion chamber 5 is discharged from an exhaust port 11. In addition, the heat generating unit 6 is provided with a temperature detecting unit 12. The temperature detection unit 12 monitors the temperature of the heating unit 6 and sends a signal to the valve 3,
Adjusting the opening of the valve 3 has the function of adjusting the amount of combustion. For this reason, the surface temperature of the heat generating portion 6 is kept constant, and the object to be heated can be heated at an optimum temperature.

FIG. 3 is a sectional view (corresponding to a view taken in the direction of arrows AA in FIG. 1) of a combustion chamber 5 according to another embodiment of the present invention. Combustion chamber 5
By providing a gap between the tip of the inner fin and the wall surface of the combustion chamber, a gap is provided between the upper surface 10b of the catalyst layer 10 and the catalyst layer 8a closely attached to the inner wall surface of the combustion chamber 5.
By doing so, catalytic combustion can be performed even on the surface of the catalyst layer 10b at the tip of the fin 7, which has not contributed to catalytic combustion so far, and the effective catalytic area for combustion can be increased, and the combustion rate can be increased. Can be further improved. In addition, since the combustion heat is supplied as radiant heat from the catalyst layer 10 b at the tip of the fin 7 to the catalyst layer 8 on the inner wall surface of the combustion chamber 5, the radiant heat is supplied from the lower surface 13 b of the catalyst layer 13, The fluctuation of the combustion temperature of the catalyst layer 8 on the wall surface of the combustion chamber caused by the fluctuation of the heating amount can be prevented, and the activity of the catalyst can be maintained.

Further, by providing a gap between the tip of the fin in the combustion chamber 5 and the wall surface of the combustion chamber, the flow passage cross-sectional area of the combustion chamber 5 is increased. For this reason, the pressure loss in the combustion chamber 5 is reduced, and the air induced by the injection power of the fuel gas is easily sucked, so that the combustion air can be supplied stably.

[0019]

As described above, the present invention comprises a mixing section for fuel gas and air, and a housing provided inside the mixing section and having a combustion chamber inside the mixing section. The fins are provided substantially in parallel, and the catalyst layer is brought into close contact with the inner wall surface of the combustion chamber and the outer wall surface of the fins, so that the fuel gas can be efficiently brought into contact with the surface of the catalyst layer. Fluctuations can be prevented and a compact heating device can be provided.

[Brief description of the drawings]

FIG. 1 is a horizontal sectional view of a heating device according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of the same device according to the present invention (as viewed in the direction of arrows AA in FIG. 1).

FIG. 3 is a vertical sectional view of a combustion chamber of a heating device according to another embodiment of the present invention.

[Explanation of symbols]

 2 Nozzle 4 Mixing part 5 Combustion chamber 6 Heating part 7 Fin 8,10 Catalyst layer

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kyoko Itaya 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-61-184319 (JP, A) JP-A-61- 72912 (JP, A) JP-A-3-125807 (JP, A) JP-B-48-38728 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) F23D 11/40, 14 / 04 F23C 3 / 00,11 / 00

Claims (1)

(57) [Claims] 1. A heat generating apparatus comprising at least a mixing section of fuel gas and air, and a housing provided with a combustion chamber inside provided downstream of the mixing section, wherein provided with fins substantially parallel to protrude toward the inside of the combustion chamber than the wall surface of the combustion chamber, the said fin tip
A heat generating device , wherein a gap is provided between a wall of the combustion chamber and a catalyst layer is provided on an inner wall of the combustion chamber and an outer wall of the fin.