JPS6119323Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid fuel combustion device configured to supply liquid fuel using the static pressure of combustion air supplied to a vaporization chamber, vaporize it, premix it with the air, and combust it. .

In a conventional combustion device of this kind, a blow passage through which combustion air flows is opened into the vaporization chamber, and a tip end of a fuel supply pipe that communicates with an oil level regulator is disposed within this opening to open into the vaporization chamber. There is. Then, the static pressure generated by the flow of combustion air is introduced into the oil level regulator,
Fuel corresponding to this static pressure is supplied to the vaporization chamber, vaporized, premixed with air, and combusted.

On the other hand, in the case of combustion stoppage, when the fuel supply stop device installed in the fuel supply pipe shuts off the inside of the fuel supply pipe and stops the fuel supply, an operation stop signal is issued from the fuel control device via the flame detector and the blower is starting to stop.

However, in conventional devices, once the fuel supply stop device operates due to combustion stop, the stop device remains in that state until the next fuel supply, so liquid fuel remains at the tip of the fuel supply pipe and is combusted again. During the preheating period of the vaporizing chamber, there is a problem in that the accumulated fuel gradually vaporizes due to the temperature increase at the tip and leaks to the outside, producing an odor.
Furthermore, if the residence time becomes long, the fuel may turn into tar at the tip.

This invention was made in view of the above drawbacks,
The oil level regulator is installed in a position where the oil level of the oil level regulator is always lower than the fuel supply port, and a fuel supply stop device is installed to shut off the fuel supply pipe when combustion is stopped, and An object of the present invention is to provide a liquid fuel combustion device that eliminates the drawbacks of the conventional liquid fuel combustion device by temporarily opening the fuel supply pipe when the static pressure introduced into the fuel tank decreases after combustion stops and reaches approximately atmospheric pressure. purpose.

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 shows a combustion device according to this embodiment. In the figure, reference numeral 1 denotes an air supply pipe that communicates with a blower (not shown) and forms a blowing path for combustion air, and has a nozzle portion 1a at its tip. Reference numeral 2 denotes an oil level regulator that communicates with a fuel tank (not shown) via a connecting pipe 3, and is installed at a position where the oil level of the oil level regulator 2 is always lower than a fuel supply port 6a, which will be described later. Reference numeral 4 denotes a float floating on the liquid fuel stored in the leveler 2, and a needle valve body 4a is fixed to the head wall of the float at a position corresponding to the outlet of the connecting pipe 3. Reference numeral 5 denotes a pressurizing pipe for introducing the air static pressure in the air supply pipe 1 into the upper space of the oil level regulator 2 and pressurizing the liquid level; 6, one end is connected to the bottom of the oil level regulator 2, and the other end is connected to the bottom of the oil level regulator 2; This is a fuel supply pipe serving as a fuel supply passage that protrudes from the inside of the nozzle portion 1a into a vaporization chamber 8 of a combustor, which will be described later, and the protruding portion of the fuel supply port 6a has a needle shape. 7
8 is a solenoid valve as a fuel supply stop device installed in the fuel supply pipe 6; 8 is the aforementioned vaporization chamber; 9 is a wall of the vaporization chamber made of a metal material with good thermal conductivity such as aluminum; A nozzle portion 1a is attached to the. 10 is an electrode of a ceramic heater 11; 12 is an insulating plate made of alumina or the like; 13
14 is a mixing promotion plate provided above the vaporization chamber 8, 14 is a flame hole plate, 15 is a flame detector, 16 is a combustion controller that controls the combustion state based on the signal from the flame detector 15, and 17 is a flame. .

The operation of the combustion apparatus having such a configuration will be explained based on the timing chart shown in FIG.

First, the ceramic heater 11 is turned on to heat the vaporization chamber wall 9 and start preheating. When the temperature of the vaporization chamber wall 9 rises to a predetermined temperature and preheating is completed, the blower (not shown) is turned on and combustion air is supplied to the vaporization chamber 8 from the nozzle portion 1a of the air supply pipe 1, and then the combustion air is supplied to the vaporization chamber 8 via the pressure pipe 5. The static air pressure generated in the air supply pipe 1 is applied to the liquid level in the oil leveler 2. Pre-purging is performed for a predetermined period of time, and when the blowing pressure from the blower becomes approximately constant, the solenoid valve 7 is turned on to open the fuel supply pipe 6, and an amount of liquid fuel corresponding to the static pressure is supplied to the supply port 6a of the fuel supply pipe 6. It is supplied to the vaporization chamber 8 from. This liquid fuel is atomized by the air jet, instantaneously vaporized on the vaporization chamber wall 9, and mixed with combustion air. The air-fuel mixture is further mixed while passing through the mixing promotion plate 13, and is ignited by an ignition device (not shown) on the flame hole plate 14 to form a stable flame 17. During combustion, flame 1 appears on the vaporization chamber wall 9.
Since heat is recovered from 7, thermal efficiency is good. In addition, the flame detector 15 constantly monitors the combustion state, and in the event that the fire is extinguished, the combustion controller 16 safely stops the combustion. Furthermore, by changing the air flow rate using the blower voltage or damper, etc., the amount of fuel is automatically adjusted in accordance with changes in static pressure, and a predetermined air-fuel ratio is always maintained, which greatly reduces harmful emissions such as soot and carbon monoxide. Stable blue flame combustion can be achieved in the same manner as before.

On the other hand, in the case of combustion stop operation, the solenoid valve 7 is
When turned OFF and the fuel supply pipe 6 is cut off to cut off the fuel supply, the fire is instantly extinguished, the flame detector 15 detects this, a combustion stop signal is issued from the combustion controller 16, the blower is turned OFF, and the blowing pressure gradually increases. The static pressure introduced into the oil level regulator 2 also decreases. When this static pressure reaches approximately atmospheric pressure, the solenoid valve 7 is turned on again to open the fuel supply pipe 6, and the position of the fuel supply port 6a is set higher than the liquid level in the oil level regulator 2. Therefore, the fuel in the fuel supply pipe 6 flows back to the oil level regulator 2 side, and no fuel remains in the vicinity of the fuel supply port 6a. Therefore, as shown in the graph of Figure 3, the amount (relative value) of unburned fuel (HC) discharged during the preheating period is significantly reduced in Figure B of the present invention compared to the conventional Figure A; Eliminates the occurrence of odors.
Further, problems such as tar formation due to long-term retention of fuel are also eliminated. Then, after the fuel flows back, the solenoid valve 7
Turn off the fuel supply pipe 6 and prepare for re-combustion.

As described above, according to the present invention, the oil level regulator is installed at a position where the oil level of the oil level regulator is always lower than the fuel supply port, and the fuel supply stop device is installed.
The fuel supply pipe is shut off when combustion is stopped, and the fuel supply pipe is temporarily opened when the static pressure introduced into the oil level regulator decreases after combustion stops and reaches approximately atmospheric pressure. , it is possible to share the fuel supply pipe without providing a return passage or the like, and cause the fuel to flow back to the oil level vessel side due to the water head difference, and liquid fuel can flow to the tip of the fuel supply pipe near the vaporization chamber. It does not stagnate and eliminates the generation of odor due to fuel vaporization during the preheating period.Furthermore, problems such as tarring of fuel due to long-term stagnation are inevitably prevented, and fuel supply pipes are not clogged.

[Brief explanation of the drawing]

Fig. 1 is a simplified configuration diagram showing one embodiment of the liquid fuel combustion device according to the present invention, Fig. 2 is a timing chart of the same device, and Fig. 3 is a comparative explanation of unburned fuel emissions between the conventional and the present invention. In the figure, A indicates the conventional method and B indicates the present invention. 1... Air supply pipe, 1a... Nozzle part, 2...
Oil level regulator, 6... fuel supply pipe, 6a... fuel supply port, 7... solenoid valve, 8... vaporization chamber.

Claims (1)

[Scope of utility model registration request] The fuel supply port of the fuel supply pipe is placed in the nozzle part of the air supply pipe connected to the vaporization chamber of the combustor, and the fuel supply pipe is connected to the oil level regulator in which liquid fuel is stored to stop the fuel supply. In the liquid fuel combustion device, the static pressure of combustion air flowing through the fuel supply pipe is introduced into the oil level regulator, and the static pressure is used to supply fuel into the vaporization chamber. The oil level regulator is installed at a position where the oil level of the oil level regulator is always lower than the fuel supply port, and the fuel supply stop device is used to shut off the fuel supply pipe when fuel is stopped and A liquid fuel combustion device characterized in that a fuel supply pipe is temporarily opened when static pressure introduced into an oil leveling device decreases after fuel stops and reaches approximately atmospheric pressure.