JPH05340534A - Liquid fuel combustion equipment - Google Patents

Abstract

PURPOSE:To estimate the time required for a heater to raise the temp. of a vaporizer and improve the responsiveness to load, in a liquid fuel combustion equipmant which, after vaporizing the liquid fuel by its vaporizer, burns it for use in room heating. CONSTITUTION:A vaporizer 3 connected to a fuel pump 1 and a combustion fan 4 in communication with a combustion part 6 is provided with a heating means 7 and a temp. detecting means 8 and, during burning operation, inputs into the heating means 7 are stopped and restarted according to the outputs from the temp. detecting means 8. A control part 9 for starting and stopping the burning operation by a load detecting means 10 activated according to the combustion heat computes the difference between the operation instructing value of the load detecting means 10 and the value thereof at the start of the actual burning operation occurring by a rise in the temp. of the vaporizer 3 upon stopping the burning operation by the load detecting means 10, adds the value equivalent to the resulting difference to the operation instruction value and uses the sum of them as the next operation instruction value of the load detecting means 10 to immediately start the combustion upon entering the burning operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid fuel combustion apparatus which is used for heating or the like after vaporizing liquid fuel by a vaporizer and then burning it.

[0002]

2. Description of the Related Art A conventional liquid fuel combustion apparatus as shown in FIG. 3 is used for heating a liquid fuel by burning it. The fuel supply pipe 2 of the fuel pump 1 faces the carburetor 3, and the combustion fan 4 is connected to the carburetor 3 by a duct 5.
The vaporizer 3 communicates with a combustion section 6 that forms a combustion flame, and the vaporizer 3 has an electric heater 7 as a heating means and a temperature thermistor 8 that detects the temperature of the vaporizer 3. A control unit 9 energizes / stops the heating unit 7 according to the output of the temperature detection unit 8 during combustion. The temperature of the carburetor 7 is detected by the temperature thermistor 8, and when the temperature of the carburetor 3 is below a certain level necessary for vaporizing the liquid fuel, the electric heater 7 is energized to heat it.
When the temperature of the carburetor 3 exceeds a certain level, the electric heater 7 is de-energized, and this cycle is repeated to control the temperature of the carburetor 3 to be constant. The control unit 9 stops combustion according to means for detecting the combustion heat to be used and its load (for example, temperature detection sensors such as water temperature and air temperature of the object to be heated, surface temperature of the heat exchanger). Control.

[0003]

However, in this liquid fuel combustion apparatus, the carburetor 3 is made of a material having good thermal conductivity such as aluminum, but the heater 7 for heating the carburetor 3 is energized. However, due to the heat capacity of the vaporizer 3, it took a long time for the vaporizer 3 to rise to the temperature required for starting combustion. Therefore, when used for heating, hot water supply, etc., the control unit 9
This caused a delay when the combustion was stopped. That is,
Even if the control unit 9 detects the load of combustion heat by the output of the load detection unit 10 and immediately starts the operation of combustion, the heater 7 serving as a heating unit brings the temperature to a predetermined temperature necessary for vaporizing the liquid fuel. Combustion does not start until the vaporizer 3 reaches a high temperature. Therefore, the heating temperature or the hot water supply temperature further decreased during this period, which was not comfortable. Therefore, there is a conventional example in which the vaporization heater continues to be energized even during combustion, but in this case, the required electricity cost was excessive.

The present invention is to solve the above-mentioned problems. The control section detects the load of combustion heat, and when the operation of combustion is started, the combustion can be started immediately without delay, and the responsiveness to the load is improved. It is a thing.

[0005]

In order to achieve the above object, the present invention provides a vaporizer which is connected to a liquid fuel supply means and a combustion air supply means and communicates with a combustion section, a heating means provided in the vaporizer, and Temperature detection means, a control section for controlling the stoppage of energization of the heating means according to the output of the temperature detection means during combustion, and a control section for stopping the combustion operation by the load detection means of the combustion section, and the load detection means being preset. A value corresponding to the difference between this operation instruction value and the value of the load detecting means at the actual start of combustion is added to the operation instruction value, and the value is set to the value for operating the combustion by the next load detecting means.

[0006]

With the above structure, the present invention predicts the time required to raise the temperature of the carburetor by the heater from the temperature output of the load detecting means, and raises the operation instruction value of the load detecting means by the value corresponding to the time. By doing so, the control unit can detect the load of combustion heat and start combustion immediately when the operation of combustion is started.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a fuel pump which is a liquid fuel supply means, and a fuel supply pipe 2 connected to the fuel pump 1 faces a carburetor 3. Reference numeral 4 is a combustion fan 4 which is a combustion air supply means, and is connected to the carburetor 3 by a duct 5. The vaporizer 3 communicates with a combustion section 6 that forms a combustion flame, and the vaporizer 3 has an electric heater 7 as a heating means and a temperature thermistor 8 as a temperature detecting means for detecting the temperature of the vaporizer 3. ing. Reference numeral 9 is a control unit for stopping the energization of the input of the heating means 7 in accordance with the output of the temperature detection means 8. The temperature of the carburetor 7 is detected by the temperature thermistor 8, and the temperature of the carburetor 3 evaporates the liquid fuel. When the temperature is below a certain level, the electric heater 7 is energized, when the temperature of the carburetor 3 exceeds a certain level, the electric heater 7 is de-energized and heating is stopped, and when the temperature of the carburetor 3 falls below a certain level again, The electric heater 7 is energized and controlled to repeat this cycle. Reference numeral 10 denotes load detecting means for the combustion heat to be used and its load, which is attached to the heat exchanger 11 through which the object to be heated flows, and the control unit 9 causes the load detecting means 10 to operate.
The combustion is controlled to be stopped according to (for example, a temperature detection sensor such as a water temperature or an air temperature of the object to be heated, a surface temperature of the heat exchanger, or the like). Reference numeral 12 is a calculation unit provided in the control unit 9 and calculates the output signal value of the load detection means 10. The difference between the output values of the load detection means 10 at the time of preset operation instruction of the load detection means 10 and when the temperature of the carburetor 3 rises and the actual combustion starts is calculated, and the value corresponding to this difference is calculated as above. In addition to the operation instruction value, the next load detection means 10
It is controlled so as to output to the control unit 9 as a driving instruction value according to. That is, the calculation unit 12 calculates and controls the following operation instruction value = operation instruction value + (operation instruction value−value at the start of combustion).

The operation of the above structure will be described with reference to FIG. When the operation is started, the electric heater 7 is energized to heat the carburetor 3, the temperature thermistor 8 which detects the temperature of the carburetor 3 outputs a temperature above a certain level, and the carburetor 3 reaches a temperature sufficient for fuel evaporation. Then, the fuel pump 1
The fuel supplied from the fuel supply pipe 2 and the primary air for combustion supplied from the combustion fan 4 through the duct 5 are supplied to the carburetor 3. In the vaporizer 3, the supplied fuel evaporates and is uniformly mixed with air, and flows into the combustion section 6 communicating with the vaporizer 3. Ignition means (not shown) ignites in the combustion section 6 to form a combustion flame. This combustion heat is used to transfer heat to the heat exchanger 11 through which the object to be heated flows. On the other hand, the electric heater 7 stops energizing. Then, the control unit 9 controls the load detection unit 10 (for example, the temperature of water or the temperature of air to be heated,
The fuel pump 1 and the combustion fan 4 are controlled so as to stop the combustion according to the combustion heat and the load thereof by receiving a signal from a temperature detection sensor such as the surface temperature of the heat exchanger. Then, when the combustion heat load detection means 10 stops the combustion, the calculation unit 12 detects the load when the operation instruction value of the load detection means 10 and the temperature of the carburetor 3 rise and actual combustion starts. The difference between the output values of the means 10 is calculated, and the value corresponding to this difference is added to the driving instruction value to be set as the driving instruction value by the next load detection means 10 and output to the control unit 9.

Therefore, the time required to raise the temperature of the carburetor 3 by the heater 7 is predicted from the temperature output of the load detecting means 10 and the operation instruction value of the load detecting means 10 is increased by the value corresponding to the time. Thus, the control unit 9 detects the load of combustion heat, and the combustion can be started immediately when the operation of combustion is started. That is, the time required to raise the temperature of the carburetor 3 by the heater 7 is predicted from the load detecting means 10, and a portion corresponding to this time is earlier than the combustion start time at the time of initial setting (required to raise the temperature. (Time) The heater 7 can be energized, so that there is no delay due to the heat capacity of the vaporizer,
In accordance with the set value output of the load detection means 10, the control unit 9 immediately starts the combustion operation operation, and the heating temperature or the hot water supply temperature responds to the load detection means 10 and becomes a comfortable state.

Further, in this method, since the heating means energizes only for the time required for combustion and the load can be optimally controlled, power and energy can be saved.

In addition, the calculation unit 12 for calculating the output from the load detection unit 10 adds the corresponding value to the value calculated and predicted from the change tendency of the load detection unit 10 and adds the corresponding value to the next load detection unit 10. By correcting the operation instruction value, the load of the combustion heat can be detected by the control unit 9 even when the load is significantly changed and the output of the load detection means 10 is greatly changed, and the combustion is immediately started when the operation of combustion is started. You can start. Therefore, the delay due to the heat capacity of the carburetor 3 does not occur, the combustion operation is immediately started by the control unit 9 in accordance with the output of the load detection unit 10, and the heating temperature or the hot water supply temperature responds to the load detection unit 10 and the comfort is improved. It will be in a state.

[0013]

As described above, according to the present invention, a carburetor which is connected to the liquid fuel supply means and the combustion air supply means and communicates with the combustion part, a heating means and a temperature detecting means provided in the carburetor, While controlling the stoppage of energization of the heating means according to the output of the temperature detection means during combustion, a control section for stopping the combustion by the load detection means of the combustion section, and a preset operation instruction value of the load detection means Since the value corresponding to the difference between this operation instruction value and the value of the load detection means at the start of actual combustion is added to the value to drive the combustion by the next load detection means, the following effect is obtained. Be done. (1) By predicting the time required to raise the temperature of the carburetor by the heater from the temperature output of the load detecting means and increasing the operation instruction value of the load detecting means by the value corresponding to the time, the control unit When the combustion heat load is detected, the combustion can be started immediately when the operation of combustion is started. (2) The heating means is energized only for the time required for combustion,
Optimal control for the load saves power,
Can save energy. (3) Even when the load fluctuates significantly and the disconnection time greatly changes, the delay due to the heat capacity of the carburetor does not occur, and when the combustion heat load is detected by the control unit, combustion starts immediately when the combustion operation starts. it can.

[Brief description of drawings]

FIG. 1 is a configuration diagram of essential parts of a liquid fuel combustion apparatus according to an embodiment of the present invention.

FIG. 2A is a driving operation cycle diagram of the same apparatus, and FIG. 2B is a driving operation cycle diagram of a conventional apparatus.

FIG. 3 is a configuration diagram of a main part of a conventional liquid fuel combustion device.

[Explanation of symbols]

 1 Fuel Pump 3 Vaporizer 4 Combustion Fan 6 Combustion Section 7 Electric Heater 8 Temperature Thermistor 9 Control Section 10 Load Detection Means 12 Computing Section

Claims (2)

[Claims] 1. A carburetor which is connected to a liquid fuel supply means and a combustion air supply means and communicates with a combustion part, a heating means and a temperature detecting means provided in the carburetor, and an output of the temperature detecting means during combustion. According to the control unit that controls the stoppage of the energization of the heating unit according to the above, and the control unit that stops the combustion by the load detection unit of the combustion unit, and the preset operation instruction value of the load detection unit, the operation instruction value and the actual combustion A liquid fuel combustion apparatus in which a value corresponding to the difference from the value of the load detection means at the time of start is added to set a value for operating combustion by the next load detection means. 2. A calculation prediction based on a change tendency of the load detection means,
The liquid fuel combustion apparatus according to claim 1, wherein the value for operating the combustion by the next load detection means is corrected by adding this value.