JPH0144962B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vaporizing oil combustor in which petroleum is preliminarily vaporized in a vaporizer by heating and then supplied to a burner through a nozzle for combustion, and particularly relates to the removal of tar produced in the vaporizing chamber. In conventional vaporizing oil combustors, when kerosene vaporizes in the vaporizing chamber during combustion, the vaporization temperature (approximately 150
It gradually turns into tar due to the polymerization of molecules or minute residues (impurities) within the temperature range (~280°C), and tar (carbide) gradually adheres to the vaporization chamber and vaporization stabilizer as the combustion time progresses. Although the amount of tar varies somewhat depending on the temperature of the vaporizer, the method of vaporizing the kerosene, and the temperature rise of the kerosene, the generation of tar was unavoidable. Therefore, when the tar adheres to the vaporization chamber and the vaporization stabilizer and accumulates, the vaporization passage becomes clogged, the amount of vaporized gas decreases, the amount of combustion decreases, and other problems occur, resulting in the product becoming unusable. There was a problem in terms of lifespan. For this reason, some solutions include replacing the vaporization chamber and vaporization stabilizer once every two to three seasons.
This product also had various problems from the viewpoint of a commercial product. For this reason, attempts have been made to remove the tar adhering to the vaporization chamber and vaporization stabilizer by dry firing at a temperature higher than the normal vaporization temperature. First, we tested the effects of dry firing using a Bunsen combustion type vaporizer. The outline of the experiment is to use a vaporizer that uses a temperature control circuit to control power supply to the heater (approximately 350W) at a constant vaporization temperature (240 to 280℃).The temperature control circuit is short-circuited and the heater is continuously energized. By doing so, the temperature inside the vaporizer was raised to 450 to 500°C, and the vaporization chamber and the vaporization stabilizer were heated dry in this high-temperature atmosphere. The experimental results were as follows.

[Explanation of circuit operation]

[1-1] First, when switches SW ₁ and SW ₂ are turned on (at this time, SW ₂ is only turned on momentarily), voltage is applied to the primary sides of the transformer, X ₁ and Y ₁ , and at the same time the secondary side Voltage is also generated on the coil R ₁₈ of RY ₂ ,
Q ₁ turns ON through D ₇ and R ₈ , resulting in relay RY ₁
is self-maintaining even when operation SW ₂ is turned OFF, and power lamp LED 1 lights up. [1-2] Timer T is “continuous” or “time up”
If it is in the state, the pump 7 is energized and at the same time
The photocoupler PC1 is energized through D ₄ , R ₂ , and R ₃ . [1-3] Since the light-receiving side transistor of PC1 turns ON, the base voltage of transistor Q ₂ is applied through R ₅ , R ₉ , and R ₁₀ , and since Q ₂ turns ON, voltage is applied to comparator IC _1-1. . [1-4] Since the temperature of the positive temperature coefficient thermistor 21 is low, its resistance is low and the output of IC _1-1 is "low", so transistor Q ₆ is turned off. [1-5] (Preheating) A full-wave rectified base current flows through transistor Q ₇ through R ₄₄ , and at the point where the current is zero, Q ₇ is OFF, so it flows to C ₁₃ through R ₄₃ and R ₄₆ . It will be charged. When Q ₈ turns ON, the charge stored in C ₁₃ is discharged to the bases of transistors Q ₈ and Q ₄ , and Q ₈ and Q ₄ turn ON for a moment, and current flows through the coil of the pulse transformer PT, turning on the triac TR. In addition, _Q8
turns off as _Q7 turns on. Heater 1 is activated by the zero-cross triggered tri-attack TR.
8 turns on. [1-6] When the vaporizer 1 is heated by the heater 18, the resistance of the positive temperature coefficient thermistor 21 attached to the vaporizer increases, and the output of the comparator CI _1-1 is reversed from "low" to "high". . As a result, the transistor _Q6 turns on, and the pulse current to the pulse transformer TR turns off, turning off the truss actuator TR, so the heater 18 is no longer energized.
It becomes OFF. [1-7] (Ignition operation) The positive input of IC _1-2 is
Since it enters through R ₁₆ , D ₈ , and C ₆ , the output of IC _1-2 is inverted from "low" to "high" and transistor Q ₃ is inverted.
ON and relay RY ₂ turns ON. Igniter IGN convection blower FM by turning on PY ₂
The solenoid valve 9 is energized. [1-8] Since RY ₂ turns on, the self-holding signal from R ₁₈ and D ₇ disappears, but as mentioned in [1-3], when transistor Q ₂ turns on, voltage is applied to the entire electronic circuit 21. Therefore, the holding signal from IC _1-4 is D ₁₂ ,
The flow continues through D ₈ , turning Q ₁ ON, and the self-retention of RY ₁ is maintained. [1-9] Carburetor 1 is activated by the spark from the igniter IGN.
When the vaporized gas is ignited from the flame rod FL
Frame resistance of comparator IC _1-3 is reduced
The voltage at the negative terminal of IC 1-3 decreases and the output of IC _1-3 changes from "low" to "high". At this time, _Q5 is turned ON and LED ₂ lights up. Also Q ₁ through R ₃₄ , D ₁₀ , R ₈
A hold signal is output to the base of. [1-10] (Ignition judgment) When the output of IC _1-2 changes to "high" and a certain period of time has passed (after completion of preheating), IC _1-2
The potential of C ₁₁ becomes high due to the output from R ₄₁ , D ₁₂ , and the output of IC _1-4 is reversed from "high" to "low".
The holding signal from R ₈ disappears. At this time, if there is no hold signal from IC _1-3 , Q ₁ turns OFF and RY ₁ also turns OFF.
It turns OFF, releases self-holding, and stops operation.
In other words, if the igniter IGN does not ignite even after discharging for a certain period of time, operation will be automatically stopped. [1-11] After starting combustion, the output of comparator IC _1-1 changes from "high" to "low" repeatedly due to the positive characteristic thermistor 21, and as a result, heater 1
8 performs ON-OFF operation and heats vaporizer 1 to 150℃
Keep at ~280℃. At this time, even if IC _1-1 output becomes "low", IC _1-2 remains "high" due to the discharge charge from C ₆ , but even after a certain period of time, no charge is supplied from IC _1-1 . If so, turn it off. [About dry firing means] [1-12] When the negative characteristic thermistor 21 is shorted with the switch 29, the output of the comparator IC _1-1 becomes low, so the transistor Q ₆ is turned off and the pulse current to the pulse transformer PT is turned on. becomes. Therefore, the triax TR is turned on and the heater 18
The power continues to be applied, and dry firing is performed. By the way, the above-mentioned dry firing only vaporizes the tar and releases it from the nozzle without burning it, so it has the disadvantage that it gives off an odor during dry firing. The present invention has been made to eliminate such drawbacks. In other words, the tar content is the remains of high boiling point components that exist in trace amounts in kerosene, so regardless of whether kerosene is present in the vaporizer, the tar content can be removed as long as the temperature of the vaporizer is high. This phenomenon is used to remove tar during combustion. One embodiment of the present invention will be described below with reference to the drawings. Note that explanations of the already mentioned symbols will be omitted. FIG. 4 is a circuit diagram of the main part of the combustor of the present invention.
is an electronic control circuit surrounded by a dashed line in FIG. That is, in FIG. 4, a series circuit of relay RY ₄ and heat-sensitive switch 32 (temperature control means for removing tar) is connected between heater 18 and relay RY ₂ ,
Immediately after the start of combustion, the tar removal operation is automatically performed. Relay RY ₄ is a switch that turns on and off at the same time as relay RY ₂ . The heat-sensitive switch 32 is provided at a certain distance from the combustion chamber, and is turned off when the temperature exceeds a certain temperature. Before the start of combustion, the switch 32 is on, but since the relay _RY4 is off, the heater 18 is not energized. When the switches SW1 and SW2 are turned on, the vaporizer 1 is first heated by the operation described above, and when the vaporizer 1 reaches a certain temperature, the relay _RY2 is turned on. When relay RY ₂ is turned on, the igniter IGN is activated and combustion begins. When combustion starts, the triac TR is turned on and off by the output of the thermistor 21 as described in [1-11], and tries to operate to control the energization to the heater 18 to keep the temperature of the carburetor 1 constant. (temperature control means for normal combustion). But when the relay coil RY ₂ works, the relay
Since relay RY ₄ turns on at the same time as RY ₂ , power is supplied to heater 18 via switch 32 and relay RY ₄ , which are connected in parallel with triac TR, and the heater 18 continues to be energized regardless of whether triac TR is on or off. It turns out. Therefore, kerosene is supplied to the vaporizer 1 by the pump P and vaporization is performed, but the temperature of the vaporizer 1 is kept at a predetermined temperature (240 to 280°C).
As the temperature continues to rise, the tar component, which is a high boiling point component, in the vaporizer is gradually vaporized. That is, the tar removal operation is automatically started. In this way, when the temperature of the vaporizer 1 reaches 500° C., most of the tar is vaporized, and is discharged from the nozzle 3 and burned together with the kerosene supplied by the pump P and vaporized. Therefore, the odor is reduced compared to the case where the tar component is directly discharged from the nozzle 3 by dry firing. Note that the amount of kerosene supplied to the vaporizer 1 is determined by the pump P.
Therefore, even if the temperature of the vaporizer 1 becomes higher than the predetermined temperature, it will only increase the vaporization rate and will have almost no effect on the combustion itself, and will not change the quality of the kerosene components. There's nothing wrong. In addition, even if the heater 18 continues to heat, the vaporizer 1
The reason why the temperature remains at 0.degree. C. is due to the relationship between the calorific value of the heater 18, the heat capacity of the vaporizer 1, the amount of heat radiation, etc. At the same time, relay RY ₄ is turned on, so that heater 18 is energized regardless of whether triax TR is on or off. In this way, the heater 18 continues to heat the vaporizer 1 and performs dry firing. When the relay RY ₂ is turned on, combustion is started by the operation of the igniter IGN, so that the tar removed from the carburetor 1 by dry firing is mixed with the vaporized gas and discharged from the nozzle 3 and burned. Therefore,
The odor is reduced compared to the case where the tar component is discharged from the nozzle 3 without being combusted by dry firing. When combustion starts, the surroundings are warmed by the combustion heat, and the surroundings of the heat-sensitive switch 32 are also heated. In this way, the temperature around the heat-sensitive switch 32 is constant (for example, 50°C).
~80°C), the switch 32 is turned off. Therefore, continuous energization to the heater 18 is stopped, and the tar removal operation is automatically terminated. In this way, since the tar removal operation is performed every time combustion occurs, the operation time may be short. From now on, heater 1 will be activated only when energizing the Taraiac TR.
8 is energized, and the temperature is controlled by the thermistor 21. [Effects] As described above, according to the present invention, dry firing is automatically performed during combustion, so that tar is mixed with the vaporized gas and discharged from the nozzle and burned. Therefore,
It is possible to reduce the odor that occurs during dry firing.

[Brief explanation of drawings]

Figure 1: Schematic configuration diagram of the vaporizing oil combustor of the present invention, Figure 2: Electrical circuit diagram of the vaporizing oil combustor with dry firing function, Figure 3: Circuit diagram showing an example of its detailed circuit. , FIG. 4: Main part circuit diagram of the combustor of the present invention. Code 1: vaporizer main body, 2: vaporization chamber, 4: gas injection nozzle, 17: vaporization stabilizer, 18: heater,
24: Burner, 32: Heat-sensitive switch.

Claims (1)

[Scope of Claims] 1. A porous vaporization stabilizer that promotes vaporization of kerosene is provided in the vaporization chamber of a vaporizer body equipped with an electric heater, and liquid fuel is supplied into the vaporization chamber from a fuel reservoir by a pump. However, in a vaporizing oil combustor in which the vaporized gas is guided to a gas injection nozzle and combusted by a burner, the electricity supply to the electric heater is controlled to adjust the temperature of the vaporizer to the set temperature for normal combustion. temperature control means for normal combustion, which automatically starts operating during combustion after preheating to disable the temperature control of the first temperature control means for a predetermined period of time, and the temperature of the vaporizer to be lower than the set temperature during normal combustion; A vaporizing oil combustor characterized in that it is provided with a temperature control means for removing tar that increases the temperature.