JPH05322125A - Heat generator - Google Patents

Abstract

PURPOSE:To obtain a compact heat generator having a small combustion chamber by providing fins in parallel with a flowing direction of mixture gas in the chamber, and bringing a catalytic layer into close contact with an inner wall surface of the chamber and outer wall surfaces of the fins. CONSTITUTION:Fins 7 are provided in parallel with a flowing direction of mixture gas in a combustion chamber 5, and a catalytic layer 10 is brought into close contact with outer wall surfaces of the fins 7. A catalytic layer 8 is provided in close contact with an inner wall surface of the chamber 5 therein. A fine platinum ignition heater 9 is heated by a dry cell, and the layer 8 approaching it is further raised at its temperature. Thus, combustion gas burned on a combustion surface and near an inlet of the chamber 5 is mixed with unburned fuel gas to flow between the layer 10 in close contact with the fins 7 and the layer 8 in close contact with the inner wall of the chamber 5. In this case, the combustion gas of high temperature is mixed with the unburned fuel gas to raise a temperature of the fuel gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat generating device used for irons, steamers, cookers, coffee makers, etc., which burns gaseous fuel or liquid fuel and uses the combustion heat as a heat source.

[0002]

2. Description of the Related Art Conventionally, as a heat generating device using combustion heat as a heat source, there are a cordless hair curler, a pocket heater, and the like. These products use butane gas or benzine as the fuel, vaporize the fuel and mix it with air, and then contact the mixed gas with a felt-like catalyst supporting a platinum catalyst to cause a catalytic reaction and to generate combustion heat. It is what you use.

[0003]

The above-mentioned combustor is one in which the amount of combustion is small 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 amount of heat generation, the amount of mixed gas that should react 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 contacts the catalyst layer must be increased, which causes a problem that the combustor becomes large.

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

[0005]

DISCLOSURE OF THE INVENTION The present invention comprises a mixing section for fuel gas and air, and a casing provided inside the mixing section and having a combustion chamber therein. The fins are provided substantially parallel to each other, and the catalyst layer is adhered to the inner wall surface of the combustion chamber and the outer wall surface of the fin.

A gap is provided between the tip of the fin in the combustion chamber and the 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 that has been heated up to the activation temperature in advance, the catalyst works near the surface of the catalyst layer, resulting in a temperature lower than that of flame combustion. It is a combustion phenomenon in which a mixed gas burns to generate an exothermic reaction. Therefore, in order to increase the combustion rate in catalytic combustion, how efficiently the mixed gas is supplied to the catalyst surface is important. The present invention has been made in view of this fact.

In the present invention, fins are provided in the combustion chamber and the catalyst layer is brought into close contact with the outer wall surfaces of the fins to increase 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 is increased, so that the heat exchange efficiency for heating the object to be heated by the combustion heat on the catalyst surface is significantly improved. Therefore, the size of the combustion chamber can be made very small.

Since such catalytic combustion causes surface combustion on the surface of the catalyst, the combustion temperature of the catalyst surface has a great influence on the combustion characteristics. On the other hand, the outer wall surface of the combustion chamber supplies heat to the object to be heated as a hot plate, so that the combustion temperature on the catalyst surface may fluctuate due to fluctuations in the amount of heating to the object to be heated. According to the present invention, not only the inner wall surface of the combustion chamber but also the heat of combustion on the catalyst surface that is in close contact with the outer wall surface of the fin is transmitted to the outer wall surface of the combustion chamber through the fins and contributes to the heating of the object to be heated. .. Since the catalyst layer adhered to the outer wall surface of the fin is not in direct contact with the heating surface, it is less susceptible to fluctuations in the heating amount of the heating surface.
The combustion temperature on the surface of the catalyst is maintained at a high temperature, and stable combustion can be performed. Moreover, since the combustion heat is supplied as radiant from the surface of the catalyst layer burning at high temperature to the wall surface of the combustion chamber, the fluctuation of the combustion temperature of the catalyst layer on the wall surface of the combustion chamber caused by the fluctuation of the heating amount of the object to be heated is 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 on arrow AA in FIG. In FIG. 1, reference numeral 1 is a liquefied gas cylinder such as propane and 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 attracting action of the gas flow, uniformly mixes it in the mixing chamber 4, and is supplied to the combustion chamber 5. Combustion chamber 5
Is provided inside the heat generating portion 6 formed of a metallic housing. The fins 7 are provided inside the combustion chamber 5 substantially parallel to the flow direction of the mixed gas, and the heat transfer efficiency of the combustion heat on the catalyst surface can be improved by increasing the heat transfer area.

A catalyst layer 8 is provided in the combustion chamber 5 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 the catalyst layer 8 further adjacent thereto is heated.
Becomes hot. When the catalyst layer 8 is heated to the activation temperature, the valve 3 is opened and the combustion gas from the nozzle 2 is mixed by 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 passed after the ignition heater 9 was energized. The air sucked by the jetting force of the fuel gas and the fuel gas 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 which has been heated to the activation temperature, the mixed gas starts to burn on the surface of the catalyst layer 8. In the vicinity of the inlet of the combustion chamber 5, only the mixed gas supplied near the wall surface of the combustion chamber burns in the vicinity of the catalyst layer 8, but the mixed gas near the center of the combustion chamber 5 remains unburned inside the combustion chamber 5. Will pass through. 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 thereof.

Fins 7 are provided in the combustion chamber 5 substantially parallel to the flow direction of the mixed gas, and the catalyst layer 10 is provided on the outer wall surface of the fins 7.
Are closely attached. 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. Combustion gas burned near the combustion surface 10a and the inlet of the combustion chamber 5 and unburned fuel gas are mixed,
It flows between the catalyst layer 10 in close contact with the fin 7 and the catalyst layer 8 in close contact with 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 this 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 burns. Catalyst layer 8
If the gap between the catalyst layer 10 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 adhered to an aluminum combustion chamber, it was confirmed that the effect was great when the gap between the catalyst layers 8 and 10 was 4 mm or less.

Moreover, 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 is increased, the heat transfer coefficient on the combustion gas side is increased, and the heat in the heat generating portion 6 is increased. Improve exchange efficiency.

Since catalytic combustion is surface combustion on the surface of the catalyst, the combustion temperature of the catalyst surface has a great influence on the combustion characteristics. On the other hand, the outer wall surface of the combustion chamber 5 supplies heat to the object to be heated as the heat generating portion 6, so that the combustion temperature of the catalyst surface 8 may fluctuate due to fluctuations in the amount of heating 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 that is in close contact with the outer wall surface of the fin 7 is transmitted to the heat generating portion 6 on the outer wall surface of the combustion chamber 5 through the fin 7. , Contributes to the heating of the object to be heated. Since the catalyst layer 10 that is in close contact with the outer wall surface of the fin 7 is not in direct contact with the heat generating portion 6, it is unlikely to be affected by fluctuations in the heating amount of the heat generating portion 6, and the combustion temperature on the surface of the catalyst layer is maintained at a high temperature. The stable combustion can be performed. Moreover, the catalyst layer 1 burning at high temperature
Since the combustion heat is supplied as radiation from the 0 surface to the catalyst layer 8 on the wall surface of the combustion chamber, it is possible to prevent the variation of the combustion temperature of the catalyst layer 8 on the wall surface of the combustion chamber caused by the variation of the heating amount of the object to be heated. ..

The combustion gas burned cleanly in the combustion chamber 5 is discharged from the exhaust port 11. Further, the heat generating section 6 is provided with a temperature detecting section 12. The temperature detecting unit 12 monitors the temperature of the heat generating unit 6 and sends the signal to the valve 3,
It has a function of adjusting the combustion amount by adjusting the opening degree of the valve 3. Therefore, the surface temperature of the heat generating portion 6 is kept constant, and the object to be heated can be heated at the optimum temperature.

FIG. 3 is a sectional view of a combustion chamber 5 according to another embodiment of the present invention (corresponding to the arrow view in the AA direction in FIG. 1). Combustion chamber 5
By providing a gap between the tips of the inner fins 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 in close contact with the inner wall surface of the combustion chamber 5.
By doing so, the 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 the catalytic combustion until now, and the catalyst area effective for the combustion can be increased. Can be further improved. In addition, since the combustion heat is supplied as radiant heat from the catalyst layer 10b at the tips of the fins 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 13b of the catalyst layer 13, and the object to be heated is It is possible to prevent 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 of 1, and to maintain the activity of the catalyst.

By providing a gap between the tip of the fin in the combustion chamber 5 and the wall surface of the combustion chamber, the cross-sectional area of the flow passage of the combustion chamber 5 becomes wider. For this reason, the pressure loss in the combustion chamber 5 becomes small, the air attracted by the jetting force of the fuel gas is easily sucked, and the combustion air can be stably supplied.

[0019]

As described above, according to the present invention, the fuel gas and air mixing section and the casing having the combustion chamber inside are provided downstream of the mixing section. By providing fins substantially parallel to each other and closely adhering the catalyst layer to the inner wall surface of the combustion chamber and the outer wall surface of the fin, the fuel gas is efficiently brought into contact with the surface of the catalyst layer, and the catalyst temperature changes due to the fluctuation of the heating amount in the heat generating part. It is possible to prevent fluctuation and make a compact heat generating device.

[Brief description of drawings]

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

FIG. 2 is a vertical cross-sectional view of the device of the present invention (viewed in the direction of arrow AA in FIG. 1).

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

[Explanation of symbols]

 2 Nozzle 4 Mixing part 5 Combustion chamber 6 Heat generating part 7 Fins 8 and 10 Catalyst layer

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kyoko Itaya 1006 Kadoma, Kadoma-shi, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A fuel gas and air mixing section, and a casing provided downstream of the mixing section and having a combustion chamber inside, and fins are provided in the combustion chamber substantially parallel to the flow direction of the mixture. A heating device, wherein a catalyst layer is adhered to the inner wall surface of the combustion chamber and the outer wall surface of the fin. 2. The heat generating device according to claim 1, wherein a gap is provided between a fin tip in the combustion chamber and a wall surface of the combustion chamber.