JP2002106788A - Liquefied petroleum gas evaporator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve the problem of a large sized device, a complex construction, and a bad responsiveness in a conventional construction of liquefied petroleum evaporator in which the whole liquefied petroleum gas in a liquefied petroleum gas container is heated. SOLUTION: In this liquefied petroleum gas evaporator, to a heat exchanger 24 disposed on a piping 37 connected to the liquefied petroleum gas container, for guiding the liquefied petroleum gas in a liquid phase, heat of vaporization is supplied by a combustor 14 having a pressure resistant structure. Therefore, a necessary quantity of the liquefied petroleum gas is vaporized, responsiveness is excellent by a simple construction, and in addition, the evaporator is safe even in an abnormal time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquefied petroleum gas vaporizer capable of stably vaporizing liquefied petroleum gas contained in, for example, a liquefied petroleum gas container even in a cold region or winter. It is.

[0002]

2. Description of the Related Art A conventional liquefied gas vaporizer has a structure as shown in FIG. That is, a circulating pipe 5 that circulates between the liquefied petroleum gas container 6 and the medium inflow space 4 is provided in the liquid phase portion 7 of the liquefied petroleum gas. Hot water heated by the boiler 1 is circulated through the pipe 3 by the medium pump 2 in the medium inflow space 4. Therefore, vaporization of the liquid phase portion 7 of the liquefied petroleum gas in the liquefied petroleum gas container 6 is promoted by the thermal energy of the hot water flowing through the circulation pipe 5. The vaporized liquefied petroleum gas is stored in the upper part of the liquefied petroleum gas container 6 as gaseous liquefied petroleum gas, and is provided outside from a gas phase pipe 8 connected to the upper part of the liquefied petroleum gas container 6, not shown. Guided to gas appliances.

[0003]

The liquefied gas vaporizer having the above-mentioned conventional structure heats the entire liquefied petroleum gas in the liquefied petroleum gas container. Therefore, the apparatus becomes large and the structure is complicated. In addition, there is a problem that responsiveness is poor.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a heat exchanger provided in a pipe for guiding a liquid liquefied petroleum gas connected to a liquefied petroleum gas container is provided with a heat-resistant combustor for evaporating heat. The liquefied petroleum gas vaporizer can supply only the required amount of liquefied petroleum gas, and has a simple configuration, good responsiveness, and is safe even in abnormal situations.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention described in claim 1 is characterized in that a heat exchanger provided in a pipe for guiding a liquid liquefied petroleum gas connected to a liquefied petroleum gas container is provided with a pressure-resistant combustor. The liquefied petroleum gas vaporizer is configured to supply only the required amount of liquefied petroleum gas by supplying the heat of vaporization, to have a simple configuration, to have a good response, and to be safe even in the event of an abnormality.

According to a second aspect of the invention, the combustor is a catalytic combustor having a flame-extinguishing mechanism at an intake port and an exhaust port, and ignites flammable gas even when flammable gas is present in the surroundings. The liquefied petroleum gas vaporizer has a safe and simple structure without any problems.

According to a third aspect of the present invention, there is provided a combustion apparatus in which an igniter for supplying a high voltage to an ignition plug provided in the combustor is connected to a igniter and which can easily perform catalytic combustion with a simple configuration. The liquefied petroleum gas vaporizer has a simple configuration.

According to a fourth aspect of the present invention, the igniter is configured to be housed in an insulated circuit box together with a power source for the igniter and a switch for opening and closing the output of the power source. The liquefied petroleum gas vaporizer has a safe and simple structure in which the sparks do not go outside and the surrounding combustible gas does not ignite.

According to a fifth aspect of the present invention, the circuit box has a pressure-resistant structure, so that the flame generated in the circuit box at the time of an abnormality does not go outside and the surrounding combustible gas does not ignite. The liquefied petroleum gas vaporizer has a simple configuration. According to a sixth aspect of the present invention, the wiring connecting the ignition plug and the igniter is covered with an insulating tube, so that the spark generated in the wiring does not go out of the insulating tube and ignites the flammable gas. It is a safe liquefied petroleum gas vaporizer that does not have a risk of liquefaction.

According to a seventh aspect of the present invention, the combustor has a heat exchanger and a heat insulating material which cover the surface so that the surrounding combustible gas does not come into direct contact with the combustor. It is a safe liquefied petroleum gas vaporizer that does not cause ignition of gas.

According to an eighth aspect of the present invention, in the combustor, a heat absorbing fin is provided in the combustion chamber or the combustion gas passage, and the heat of the combustion gas is absorbed by the heat absorbing fin, so that the temperature of the combustion gas becomes the ignition temperature of the combustible gas. The liquefied petroleum gas vaporizer is set to be lower so that there is no risk of igniting the combustible gas.

According to a ninth aspect of the present invention, there is provided a combustion control apparatus for controlling a flow rate control valve for controlling a flow rate of a liquid liquefied petroleum gas flowing through a pipe in accordance with a temperature of a temperature sensor provided in a combustor. A safe liquefied petroleum gas vaporizer that can keep the surface temperature of the vessel below the ignition temperature of the flammable gas and does not cause the flammable gas to ignite.

According to a tenth aspect of the present invention, when the temperature sensor detects a temperature rise due to the combustion of the flammable gas that has entered through the intake port, the flow rate control valve is closed to stop the combustion. A safe liquefied petroleum gas vaporizer that does not ignite any gas.

According to the eleventh aspect of the present invention, the operation of the combustor is stopped when a gas sensor provided outside the combustor detects the presence of a combustible gas having a predetermined concentration or more. A safe liquefied petroleum gas vaporizer that does not ignite flammable gas.

[0015]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is a sectional view showing a configuration of a liquefied petroleum gas vaporizer of the present embodiment. The liquefied petroleum gas vaporizer of the present embodiment includes a heat exchanger 24 provided in a pipe 37 for guiding a liquefied petroleum gas in a liquid phase connected to a liquefied petroleum gas container (not shown). It has a combustor 14 for supplying heat and a pipe 38 for guiding the vaporized liquefied petroleum gas to gas equipment (not shown).

The combustor 14 burns the liquefied petroleum gas or the like introduced from the fuel introduction section 35, and supplies the heat generated by the combustion to the heat exchanger 24 via the heat conducting plate 25. The liquefied petroleum gas passing through 24 is vaporized. Further, the exhaust gas generated by the combustion is exhausted by the exhaust unit 36.
From the exhaust. The heat conductive plate 25 uses a metal material having high heat conductivity, such as copper or aluminum. The heat conduction plate 25 does not necessarily have to be used, and there is no problem even if the combustor 14 is directly attached to the heat exchanger 24.

In the present embodiment, the combustor 14 has a sufficient thickness so as to efficiently supply the generated heat to the heat exchanger 24 and to prevent the combustible gas from being destroyed even if exploded therein. It has a pressure-resistant structure using die-cast aluminum. Further, the combustor 14 includes a combustion catalyst 21 therein and a spark plug 15 that generates an electric spark by a high voltage. The spark plug 15 is fixed to the combustor 14 by, for example, screwing. The combustion catalyst 21 has a configuration in which a metal formed in a honeycomb shape is used as a carrier in order to enhance heat resistance, and platinum used as a catalyst is supported on the carrier.

A circuit box 17 is provided outside the combustor 14. In this embodiment, the circuit box 17 is a thick-walled pressure vessel made of aluminum in order to have a pressure-resistant structure and to reduce the weight. However, there is no particular need for a pressure-resistant structure, and there is no problem as long as the flame generated inside does not leak out. The surface of the circuit box 17 is insulated by a heat-resistant plastic resin or the like to make the circuit box 17 insulative. An igniter 16 for generating a high voltage and a battery 23 for supplying power to the igniter 16 are provided in the circuit box 17.
And the wiring 41 between the spark plug 15 and the igniter 16 and the battery 2
The wiring 41 between the igniter 3 and the igniter 16 is housed.

The wiring 41 has an insulating tube 40 around it. The insulating tube 40 uses, for example, a molded product of a heat-resistant plastic resin.

The fuel introduction section 35 has a nozzle 19 for ejecting liquefied petroleum gas supplied through the on-off valve 18 and an intake air from which air is sucked by an ejector effect when the liquefied petroleum gas is ejected from the nozzle 19. A port 11 and a throat 2 where the liquefied petroleum gas is mixed with air to become a combustible gas;
0.

The exhaust section 36 has an exhaust port 12 for exhausting the exhaust gas after combustion. A quenching mechanism 13 is provided at the intake port 11 and the exhaust port 12. The flame-extinguishing mechanism 13 is a multi-layered metal net or a metal foil formed in a honeycomb shape, and the flame generated by forming a gap smaller than a distance at which a liquefied petroleum gas such as propane is extinguished. To extinguish the flame.

The opening / closing valve 18 starts and stops the supply of the fuel gas to the nozzle 19, and has a manual opening / closing structure in this embodiment.

Hereinafter, the operation of this embodiment will be described.
Liquefied petroleum gas such as propane gas is widely used in ordinary households and the like. The liquefied petroleum gas is housed in a gas cylinder, and gasified liquefied petroleum gas is supplied to gas appliances in the house by a pipe connected to the upper part of the gas cylinder.

At this time, in a situation where the ambient temperature is low, such as in winter, the supply of vaporization heat for vaporizing the liquefied petroleum gas in the liquid phase is not sufficient, so that the gas equipment cannot be used as expected. .

The liquefied gas vaporizer of this embodiment can sufficiently vaporize liquefied petroleum gas in such a situation or when liquefied petroleum gas is used in a cold region, so that the gas equipment can be freely operated. It is used to make it usable.

When the user opens the on-off valve 18 and supplies a fuel gas such as liquefied petroleum gas to the fuel introduction section 35, the apparatus performs catalytic combustion and supplies heat generated by the catalytic combustion to the heat exchanger 24. That is, when the on-off valve 18 is opened, the nozzle 1
The liquefied petroleum gas is ejected to 9, and external air is sucked from the intake port 11 by an ejector effect due to the energy at the time of ejection. Thus, when passing through the throat 20, the liquefied petroleum gas is mixed with the sucked air to become a combustible mixed gas. This combustible mixed gas is supplied to the combustor 1
4 is supplied to the combustion catalyst 21.

At this time, when the user presses the ignition switch 22 protruding outside the circuit box 17, the battery 2
The power of No. 3 flows to the igniter 16, and a high voltage is generated in the igniter 16. The igniter 16 is connected to a spark plug 16 disposed in the combustor 14, and the spark plug 16 generates an electric spark by discharging with a high voltage.

The mixed gas filling the combustor 14 is ignited by the electric spark. That is, a flame is formed downstream of the combustion catalyst 21. This flame heats the combustion catalyst 21 to increase the temperature. When the temperature of the combustion catalyst 21 becomes 200 ° C. to 300 ° C. or higher, which is the catalyst combustible temperature, the combustion catalyst 21 exhibits activity and starts catalytic combustion. Upon entering catalytic combustion, the flame of the mixed gas extinguishes spontaneously. That is, safe flameless combustion is achieved.

The heat generated by the catalytic combustion is supplied to the heat exchanger 24 via the heat conducting plate 25. Alternatively, it is supplied directly to the heat exchanger 24.

As shown in FIG. 1, the heat exchanger 24 has a pipe 37 connected to a liquefied petroleum gas cylinder (not shown) and a pipe 38. Liquid-phase liquefied petroleum gas flows into the pipe 37 from a liquefied petroleum gas cylinder. The liquid-phase liquefied petroleum gas receives heat of combustion generated by the combustor 14 and exchanges heat with a heat medium that generates heat. The liquefied petroleum gas that has been converted into a gas phase by this heat exchange flows through a pipe 38 and is sent to gas equipment (not shown).

As described above, when the liquefied petroleum gas is used in a winter environment or when the liquefied petroleum gas is used in a cold region, sufficient vaporization of the liquefied petroleum gas in the liquid phase can be achieved by using the apparatus of this embodiment. Heat can be supplied, and gaseous liquefied petroleum gas can be sufficiently supplied.

At this time, sufficient safety can be maintained even if liquefied petroleum gas leaks for some reason and flammable gas is present around the combustion device of this embodiment. That is, the combustion in the combustor 14 is a flameless combustion by the catalytic combustion as described above. However, even if a flame is generated in the combustor 14 for some reason, in this embodiment, the intake An extinguishing mechanism 13 is provided at the port 11 and the exhaust port 12. That is, the flame generated by the flame-extinguishing mechanism 13 is extinguished. Therefore, the combustible gas outside the combustor 14 does not ignite. Further, even if a flame is generated in the combustor 14 due to an abnormality, the flame does not go out of the combustor 14 in this embodiment because the combustor 14 has a pressure-resistant structure. That is, the combustible gas existing around the combustor 14 is not ignited.

Even if the flammable gas is present around the circuit box 17, the flammable gas does not ignite. That is, an electric spark is generated from the connection between the spark plug 15 and the igniter 16 and the battery 23, and the circuit box 17
Even if the flammable gas that has entered inside ignites, the circuit box 17 has a pressure-resistant structure in this embodiment, so that the flame does not leak to the outside.

In this embodiment, the circuit box 17 is made insulative. That is, the surface is covered with a heat-resistant resin or the like. Therefore, the circuit box 17 does not generate a spark due to the high voltage generated by the igniter 16.

The wiring 41 between the ignition plug 15 and the igniter 16 has an insulating tube 40 around it.
In this embodiment, the insulating tube 40 is made of a heat-resistant plastic resin. Therefore, even if a small spark is generated in the wiring 41 due to deterioration of the insulating film of the wiring 41, the spark does not go out of the insulating tube 40.

Therefore, as described above, the circuit box 1
Even if a flammable gas is present in the vicinity of 7, the flammable gas does not ignite.

At this time, in this embodiment, the combustor 14
Is adapted to supply heat of vaporization to the heat exchanger 24 provided in the pipe 37. That is, only the liquefied petroleum gas in the liquid phase supplied from the liquefied petroleum gas cylinder not shown is vaporized. In other words, it does not heat the entire liquefied petroleum gas contained in the liquefied petroleum gas cylinder, but heats only the liquefied petroleum gas in the liquid phase flowing through the pipe 37. For this reason, for example, even if the ambient temperature is very low, the liquid-phase liquefied petroleum gas can be efficiently vaporized, and the use of gas equipment (not shown) can be freely performed.

As described above, according to the present embodiment, the heat exchanger 24 provided on the pipe 37 for guiding the liquid liquefied petroleum gas connected to the liquefied petroleum gas container, With the configuration provided with the combustor 14 that supplies liquefied petroleum gas, only the required amount of liquefied petroleum gas can be vaporized, and a simple configuration, good responsiveness, and a safe liquefied petroleum gas vaporization device are realized. .

(Embodiment 2) Next, a second embodiment of the present invention will be described. FIG. 2 is a sectional view showing the configuration of a combustor used in the liquefied gas vaporizer of the present embodiment.

In this embodiment, heat exchangers 24 are mounted on both sides of the combustor 14, and a heat insulating material 26 is mounted on the remaining surfaces. That is, the combustor 14 has a configuration in which the surface is covered with the heat exchanger 24 and the heat insulating material 26. For this reason, the surface of the combustor 14, which is hot,
They do not come into direct contact with external combustible gases.
Therefore, according to the present embodiment, it is possible to realize a safe liquefied petroleum gas vaporizer that does not cause ignition of the combustible gas.

(Embodiment 3) Next, a third embodiment of the present invention will be described. FIG. 3 is a sectional view showing the configuration of the liquefied gas vaporizer of the present embodiment. In this embodiment, the combustion chamber 21
An endothermic fin 27 is provided in a combustion gas passage 21b through which exhaust gas after catalytic combustion in the combustion chamber 21 passes.
The heat absorbing fins 27 are made of a metal plate, and absorb heat generated by catalytic combustion of liquefied petroleum gas in the combustion chamber 21. In the present embodiment, by providing the heat absorbing fins 27, the temperature of the combustion gas can be suppressed to about 450 ° C. or less. The temperature of 450 ° C. is lower than the ignition temperature of the combustible gas.

Therefore, according to the present embodiment, a safe liquefied petroleum gas vaporizer which does not have a risk of igniting a combustible gas is realized.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described. FIG. 4 is a sectional view showing the configuration of the liquefied gas vaporizer of the present embodiment. In the present embodiment, the combustor 14
Temperature sensor 28 provided on the surface of the
Has a control circuit 30 that operates according to the signal of

That is, the control circuit 30 controls the temperature sensor 2
The opening of the flow control valve 29 is controlled in accordance with the temperature detected by the control unit 8. By controlling the opening of the flow control valve 29, the amount of liquefied petroleum gas flowing into the fuel introduction section 35 can be controlled, and the surface temperature of the combustor 14 can be controlled to 400 ° C. or less. Therefore, according to the present embodiment, a safe liquefied petroleum gas vaporizer that does not have a risk of igniting the combustible gas is realized.

(Embodiment 5) Next, a fifth embodiment of the present invention will be described. FIG. 5 is a sectional view showing the configuration of the liquefied gas vaporizer of the present embodiment. In this embodiment, the combustor 1
4, a temperature sensor 31 is provided.
The control circuit 33 is configured to close the solenoid valve 32 in response to this signal. That is, when the signal of the temperature sensor 31 exceeds a predetermined temperature, the control circuit 33 determines that, for example, combustible gas that has entered through the intake port 11 has burned. In this case, as described above, the supply of the liquefied petroleum gas which is the fuel gas for the catalytic combustion is stopped by closing the electromagnetic valve 32. Therefore, according to the present embodiment, a safe liquefied petroleum gas vaporizer that does not have a risk of igniting the combustible gas is realized.

(Embodiment 6) Next, a sixth embodiment of the present invention will be described. FIG. 6 is a sectional view showing the configuration of the liquefied gas vaporizer of the present embodiment. In this embodiment, a gas sensor 34 is provided outside the circuit box 17. The type of the gas sensor 34 is not particularly limited as long as it reacts with liquefied petroleum gas. The detection signal of the gas sensor 34 is transmitted to the control circuit 33. Control circuit 3
If the signal from the gas sensor 34 exceeds a predetermined concentration, the operation of the combustor 14 is stopped, assuming that combustible gas exists in the vicinity. That is, the supply of the liquefied petroleum gas is stopped by closing the electromagnetic valve 32.

Therefore, according to the present embodiment, a safe liquefied petroleum gas vaporizer that does not cause ignition of combustible gas is realized.

[0048]

According to the first aspect of the present invention, there is provided a heat exchanger for vaporizing liquid liquefied petroleum gas, and a combustor for supplying heat of vaporization to the heat exchanger, wherein the combustor has a pressure-resistant structure. As a result, only the required amount of liquefied petroleum gas can be vaporized,
A liquefied petroleum gas vaporizer which has a simple configuration, has good responsiveness, and is safe even in the event of an abnormality.

According to a second aspect of the present invention, the combustor is configured as a catalytic combustor having a flame-extinguishing mechanism at an intake port and an exhaust port, so that even when a combustible gas is present around the combustor, A liquefied petroleum gas vaporizer with a safe and simple configuration that does not emit flame to the outside from a combustor and does not ignite combustible gas.

According to a third aspect of the present invention, there is provided a combustion apparatus in which a combustor is connected to an igniter for supplying a high voltage to an ignition plug provided in the combustor, so that catalytic combustion can be easily performed with a simple configuration. This realizes a liquefied petroleum gas vaporizer having a simple configuration.

According to a fourth aspect of the present invention, the igniter is configured to be housed in an insulated circuit box together with a power supply for the igniter and a switch for opening and closing the output of the power supply. The present invention realizes a liquefied petroleum gas vaporizer having a safe and simple configuration in which sparks do not go outside and do not ignite surrounding flammable gas.

According to a fifth aspect of the present invention, the circuit box is configured to have a pressure-resistant structure, so that the flame generated in the circuit box in the event of an abnormality does not go out and ignites the surrounding flammable gas. A liquefied petroleum gas vaporizer with a safe and simple configuration is realized.

According to a sixth aspect of the present invention, the wiring for connecting the ignition plug and the igniter is covered with an insulating tube, so that the spark generated in the wiring does not go out of the insulating tube, and the flammability is reduced. It is intended to realize a safe liquefied petroleum gas vaporizer that does not cause ignition of gas.

According to a seventh aspect of the present invention, the combustor has a structure in which the surface is covered with a heat exchanger and a heat insulating material, so that the surrounding combustible gas does not directly contact the combustor, and the combustor has a flammable property. It is intended to realize a safe liquefied petroleum gas vaporizer that does not cause ignition of gas.

In the invention described in claim 8, the combustor has a structure in which heat-absorbing fins are provided in the combustion chamber or the combustion gas passage, and the heat of the combustion gas is absorbed by the heat-absorbing fins so that the temperature of the combustion gas becomes flammable gas. The present invention realizes a safe liquefied petroleum gas vaporizer that does not have a risk of igniting combustible gas by lowering the ignition temperature of the liquefied petroleum gas.

According to a ninth aspect of the present invention, a flow rate control valve for controlling the flow rate of a liquid liquefied petroleum gas flowing through a pipe is controlled in accordance with the temperature of a temperature sensor provided in the combustor. The surface temperature of the flammable gas can be controlled to be lower than the ignition temperature of the flammable gas, thereby realizing a safe liquefied petroleum gas vaporizer without fear of igniting the flammable gas.

According to a tenth aspect of the present invention, the flow rate control valve is closed when the temperature sensor detects a temperature rise due to the combustion of the flammable gas entering from the intake port. It is intended to realize a safe liquefied petroleum gas vaporizer without the risk of ignition.

According to the eleventh aspect of the present invention, a gas sensor is provided outside the combustor, and the operation of the combustor is stopped when the gas sensor detects the presence of a combustible gas having a predetermined concentration or more. As a configuration, a safe liquefied petroleum gas vaporizer that does not cause ignition of combustible gas is realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a liquefied gas vaporizer according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a main part of a liquefied gas vaporizer according to a second embodiment of the present invention.

FIG. 3 is a sectional view showing a configuration of a liquefied gas vaporizer according to a third embodiment of the present invention.

FIG. 4 is a sectional view showing a configuration of a liquefied gas vaporizer according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a liquefied gas vaporizer according to a fifth embodiment of the present invention.

FIG. 6 is a sectional view showing a configuration of a liquefied gas vaporizer according to a sixth embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a configuration of a conventional liquefied gas vaporizer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Intake port 12 Exhaust port 13 Flame extinguishing mechanism 14 Combustor 15 Spark plug 16 Igniter 17 Circuit box 21 Combustion catalyst 21b Combustion gas passage 24 Heat exchanger 26 Insulation material 27 Heat absorption fin 28 Temperature sensor 29 Flow control valve 30 Control circuit 31 Temperature sensor 32 Solenoid valve 33 Control circuit 34 Gas sensor 35 Fuel introduction part 36 Exhaust part 37 Piping 38 Piping 40 Insulating pipe 41 Wiring

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takaaki Kusaka 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 3E072 DB03 3K068 AA11 AB21 AB36 CA01 CA25 CB01

Claims (11)

[Claims] 1. A heat exchanger for vaporizing liquid liquefied petroleum gas, and a combustor for supplying heat of vaporization to the heat exchanger,
A liquefied petroleum gas vaporizer in which the combustor has a pressure-resistant structure. 2. The liquefied petroleum gas vaporizer according to claim 1, wherein the combustor is a catalytic combustor having a quenching mechanism at an intake port and an exhaust port. 3. The liquefied petroleum gas vaporizer according to claim 2, wherein the combustor has an igniter for supplying a high voltage to an ignition plug provided in the combustor. 4. The liquefied petroleum gas vaporizer according to claim 3, wherein the igniter is housed in an insulating circuit box together with a power supply for the igniter and a switch for opening and closing the output of the power supply. 5. The circuit box according to claim 4, wherein the circuit box has a withstand voltage structure.
Liquefied petroleum gas vaporizer described in 1. 6. The liquefied petroleum gas vaporizer according to claim 3, wherein a wiring connecting the ignition plug and the igniter is covered with an insulating tube. 7. The liquefied petroleum gas vaporizer according to claim 1, wherein the surface of the combustor is covered by a heat exchanger and a heat insulating material. 8. The liquefied gas vaporizer according to claim 1, wherein the combustor is provided with a heat absorbing fin in a combustion chamber or a combustion gas passage. 9. A flow control valve for controlling a flow rate of a liquid liquefied petroleum gas flowing through a pipe according to a temperature of a temperature sensor provided in a combustor. Liquefied petroleum gas vaporizer. 10. The liquefied petroleum gas vaporizer according to claim 9, wherein the flow rate control valve is closed when the temperature sensor detects a temperature rise due to combustion of the combustible gas that has entered through the intake port. 11. A gas sensor is provided outside the combustor,
The liquefied petroleum gas vaporizer according to any one of claims 1 to 10, wherein the operation of the combustor is stopped when the gas sensor detects the presence of a combustible gas having a predetermined concentration or more.