JPH0371607B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a vaporizer for a liquid combustor that pressure-feeds liquid fuel into a heated vaporizer tube, vaporizes it, and ejects it from a nozzle at high speed to burn it. .

BACKGROUND TECHNOLOGY The conventional vaporizer of this type of liquid fuel combustor is called the Bunsen type, and as shown in FIG. A fuel supply pipe 4 was connected to the fuel supply pipe 3, and a nozzle 5 having an opening of about 0.5 to 0.8 mm was provided at the other end. The heater 2 that heats the vaporizing tube 1 was regulated to a constant temperature by turning on and off electricity using a thermistor 6 that detected the temperature near the vaporizing tube 1.

Problems to be Solved by the Invention However, in the above configuration, the amount of combustion increases or decreases, resulting in changes in the amount of heat generated and deterioration and instability of the combustion state. The amount of combustion, that is, the amount of fuel supplied, is determined by the P-Q characteristics of the fuel pump 3 and the loss pressures of the fuel supply pipe 4, vaporizer pipe 1, and nozzle 5, but most of the loss pressure is caused by the fuel gas passing through the hole of the nozzle 5. It occurs when Therefore, when the temperature of the vaporizer tube 1 changes, the temperature of the fuel gas flowing through the nozzle 5 changes, so the volume of vaporized fuel gas per weight changes, and the loss resistance passing through the nozzle 5 decreases as the temperature decreases.
The higher the temperature, the larger the combustion amount, the lower the temperature of the vaporizer tube 1, the greater the combustion amount, and the higher the temperature, the lower the combustion amount. Further, the P-Q characteristic of the fuel pump 3 greatly increased or decreased depending on the power supply voltage, causing a change in the amount of combustion. When the combustion amount changes in this way, not only does the calorific value not reach the set value, but also causes discomfort and danger such as misfires, standing flames, and the generation of odors.

Means for Solving the Problems In order to solve the above problems, the vaporizer for a liquid fuel combustor of the present invention is configured to change the nozzle area in accordance with changes in the vaporization chamber temperature.

Effects of the present invention With the above-described configuration, the temperature of the pressure regulating body changes according to the temperature of the vaporization chamber, and by increasing or decreasing the nozzle area, the pressure inside the vaporization chamber is kept constant and fluctuations in the discharge pressure of the fuel pump are suppressed. This allows the combustion amount to be maintained at a predetermined level at all times.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In FIG. 1, 1 is a vaporizer tube.
This vaporizing tube 1 is provided with a heater 2 inside thereof, and one end of the vaporizing tube 1 is communicated with a fuel supply pipe 4 connected to a fuel pump 3, and the other end is communicated with a nozzle 5. The heater 2 is turned on and off by a thermistor 6 that detects the temperature of the vaporizing tube 1. The rod 7 provided opposite the nozzle 5 is a solenoid 8.
It moves left and right to open and close the hole of the nozzle 5. 1st
The figure shows the rod 7 blocking the nozzle 5.
During combustion, the rod 7 is connected to the nozzle 5 by the solenoid 8.
The nozzle 5 moves out of the hole, and the nozzle 5 opens. Reference numeral 9 denotes a pressure regulating body provided through the center of the nozzle 5, which passes through the center of the rod 7 and has its other end fixed to the outer shell of the nozzle 5. The pressure regulating body 9 has a rod 7 rotating around its outside and is made of a material having a coefficient of thermal expansion smaller than that of the material of the nozzle 5. During combustion, the rod 7 moves to the left from the hole in the nozzle 5, and only the pressure regulator 9 intervenes inside the nozzle 5. Therefore, fuel is ejected. The opening area of the nozzle 5 is the opening area of the nozzle 5 minus the area of the pressure regulator.

Next, the operation of the above configuration will be explained.

The solenoid 8 is energized to open the nozzle 5 by the movement of the rod 7, and the heater 2 is energized to heat the vaporizing tube 1. When the vaporizing tube 1 reaches a predetermined temperature, the fuel pump 3 is energized to supply fuel. It passes through a pipe 4 and is supplied to the vaporization pipe 1. The fuel supplied to the vaporizer tube 1 becomes vaporized gas and is ejected from the hole of the nozzle 5 because the vaporizer tube 1 is at a high temperature. When the fuel is vaporized, the volume increases significantly, so the pressure inside the vaporization tube becomes high and the fuel is ejected from the hole of the nozzle 5 at high speed. Therefore, the fuel gas flow simultaneously sends air into the burner section 12 facing the nozzle 5, mixes it inside the burner section 12, and blows it out from the burner port of the burner section 12 as a premixed mixture to form a flame. The temperature of the vaporizing tube 1 is controlled by turning the heater 2 on and off using a thermistor 6, but the amount of fuel evaporation as a heat load changes greatly by adjusting the amount of heat generated. Therefore, the temperature inside the vaporizing tube 1 changes to be higher than the differential temperature of the on/off control, and the temperature of the fuel gas flowing out from the nozzle 5 changes accordingly. The combustion amount is set by adjusting the capacity of the fuel pump 3 using the controller 11. The amount of combustion is
P-Q characteristics (discharge pressure, flow rate) of the fuel pump 3,
It is determined by the loss resistance of the fuel supply pipe 4, the loss resistance of the vaporizing pipe 1, and the loss resistance of the nozzle 5. fuel pipe 4
The loss resistance of the vaporizer tube 1 is because the fuel is liquid and its volume is small. In addition, since the passage area is large and the flow velocity is slow, nozzle 5
Most of the loss resistance occurs when passing through the hole of the nozzle 5. The volume of the nozzle 5 and the pressure regulating body 9 changes due to thermal expansion depending on the fuel gas temperature, and the hole area of the nozzle 5 is the area obtained by dividing the area of the pressure regulating body 9 from the hole area of the nozzle 5. Pressure regulating body 9
Since the nozzle body 5 is made of a material having a smaller coefficient of thermal expansion than the nozzle body 5, the opening area of the nozzle 5 increases when the fuel gas temperature increases, and decreases when the fuel gas temperature decreases. If the expansion rate of the pressure regulating body 9 is selected according to the temperature change of the specific gravity of the fuel gas, the pressure inside the vaporization chamber 1 can be kept constant at all times, and the discharge pressure of the fuel pump 3 becomes constant. Even if the temperature changes, the amount of combustion can be maintained at a predetermined value. In addition, when tar is generated and adheres to the nozzle 5, the temperature of the nozzle 5 and the pressure regulating body 9 change according to the temperature change of the vaporizer tube 1, and the shape changes due to different thermal expansion. The aperture area of No. 5 changes. Therefore, the attached tar is peeled off from the nozzle 5 and the pressure regulator 9, and is discharged from the nozzle 5 to the outside.

Effects of the Invention As described above, the vaporization device for a liquid fuel combustor of the present invention provides the following effects.

(1) Insert a pressure regulating body into the nozzle, and the pressure regulating body:
Since the nozzle is made of a material with a smaller coefficient of thermal expansion than the material of the nozzle, the opening area of the nozzle increases or decreases according to the temperature change of the fuel vaporized gas, so that it is balanced with the increase or decrease in volume due to the temperature change of the fuel vaporized gas. The pressure in the vaporization chamber can be kept constant. As a result, the discharge pressure of the fuel pump remains constant, and the set combustion amount can be maintained at all times, allowing for good combustion without causing flames due to disturbances in the air-fuel ratio, overheating due to changes in odor or combustion amount, or the generation of CO.

(2) Even when tar occurs and adheres to the nozzle,
Since the nozzle opening area changes in response to changes in the temperature of the vaporizing tube, tar peels off from the nozzle portion and is discharged outside the nozzle. Therefore, reliability can be maintained for a long period of time without clogging the nozzle.

(3) Since there is no change in combustion amount due to ON/OFF of the heater, the usable combustion range can be set wider, and a burner with high comfort and energy saving can be provided.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a main part of a vaporizer for a liquid fuel combustor according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view of a main part of a vaporizer for a conventional liquid fuel combustor. 1... vaporizer pipe, 2... heater, 3... fuel pump, 5... nozzle, 9... pressure regulator.

Claims (1)

[Claims] 1. A vaporizing pipe having a heater, a fuel pump communicating with one end of the vaporizing pipe, and a nozzle communicating with the other end of the vaporizing pipe are provided, a pressure regulating body is inserted into the nozzle, and the pressure regulating body is A vaporizer for a liquid fuel combustor made of a material having a coefficient of thermal expansion smaller than that of the nozzle material.