JP3128943B2 - Liquid fuel combustion device - Google Patents

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 for vaporizing a liquid fuel by a vaporizer and then burning the same to use for heating or the like.

[0002]

2. Description of the Related Art There is a conventional liquid fuel combustion apparatus as shown in FIG. In this case, 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 the duct 5.
The carburetor 3 communicates with a combustion section 6 forming a combustion flame, and the carburetor 3 has an electric heater 7 as a heating means and a temperature thermistor 8 for detecting the temperature of the carburetor 3.
During the combustion, the control unit 9 cuts off the input of the heating means 7 according to the output of the temperature detection means 8. The temperature of the vaporizer 7 is detected by a temperature thermistor 8, and when the vaporizer 3 is below a certain temperature necessary for vaporizing the liquid fuel, the electric heater 7 is energized and heated, and when the vaporizer 3 becomes above a certain temperature, electricity is generated. The heater 7 is turned off to stop heating, and the cycle is controlled to be repeated. The control unit 9 is means for detecting the combustion heat to be used and the load thereof (for example, a temperature detection sensor such as a temperature of a water or an air to be heated or a surface temperature of a heat exchanger).
Is controlled so as to stop the combustion in accordance with.

[0003]

However, since the vaporizer 3 in this liquid combustion apparatus is made of a material having good heat conductivity such as aluminum, a heater 7 for heating the vaporizer 3 is used.
However, because of the heat capacity of the carburetor 3, it took a long time for the carburetor 3 to rise to the temperature required for starting combustion. Especially when load fluctuations are large, the load calorie and combustion heat
Imbalance will result in more combustion shutdowns. That
As a result, the range of fluctuation has expanded significantly. Therefore, when the combustion is stopped by the control unit 9 when used for heating, hot water supply, or the like, a delay occurs. That is, even if the control unit 9 detects the load of the combustion heat by the output of the load detection means 10 and immediately starts the combustion operation, the combustion is continued until the vaporizer 3 reaches a predetermined vaporization temperature by the heater 7 until the vaporizer 3 reaches a high temperature. Do not start. For this reason, the heating temperature or the hot water supply temperature further decreased during this time, and it was not in a comfortable state. Therefore, there is an example in the past where the electric heater and this control were continuously energized even during combustion,
In this case, the cost of electricity was excessive.

[0004] In order to solve the above-mentioned problems, the present invention predicts the time required for heating a vaporizer by a heater,
By turning on the heater in advance of the combustion start time in advance, the control unit detects the load of combustion heat and can start combustion immediately after starting combustion operation without delay.
The purpose is to improve the response to a load.

[0005]

According to the present invention, there is provided a vaporizer coupled to a liquid fuel supply unit and a combustion air supply unit and connected to a combustion unit, and a heating unit provided in the vaporizer. A temperature detection unit, a control unit that controls the energization and stop of the heating unit according to the output of the temperature detection unit during combustion, and stops the combustion by the load detection unit of the combustion unit, and calculates the operation stop time. The control unit, by the output of the calculation unit,
The load detecting means is used to restart the operation after stopping the combustion.
Stop from the first energization of the heating means from cycle time
The arithmetic unit calculates a time obtained by subtracting the time until
The value is the cycle time to restart operation from the next combustion stop.
To control the heating means, and after the combustion is stopped again.
The value calculated and predicted from the increase / decrease tendency of the cycle time to operate
From the first energization of the heating means to the stop
Is calculated by the calculation unit, and this value is
The cycle time is set as the cycle time for operating again .

[0006]

The [action] The present invention is the arrangement, when stopping operation of the combustion by means for detecting the load of the combustion heat, the load sensing hand
The time obtained by subtracting the time from the first energization by the heating means to the stop of the cycle from the cycle time for restarting the combustion by the stage to the restart is the time to the next stop of the heating means. That is, the time required for the vaporizer to be heated by the heater is predicted, and the heater is energized earlier than the combustion start time, so that the control unit detects the load of the combustion heat, and the combustion operation is started. Combustion can be started immediately upon entering.

[0007]

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

In FIGS. 1 and 2, reference numeral 1 denotes a fuel pump, and a fuel supply pipe 2 connected to the fuel pump 1 faces a carburetor 3. Reference numeral 4 denotes a combustion fan 4 serving as combustion air supply means, which is connected to the carburetor 3 by a duct 5. The carburetor 3 communicates with a combustion section 6 forming a combustion flame, and the carburetor 3 is provided with an electric heater 7 as a heating means.
And a temperature thermistor 8 as temperature detecting means for detecting the temperature of the vaporizer 3. Reference numeral 9 denotes a control unit that energizes and stops the input of the heating unit 7 in accordance with the output of the temperature detection unit 8, and detects the temperature of the vaporizer 7 with the temperature thermistor 8.
The electric heater 7 is energized when the temperature of the vaporizer 3 is lower than a certain temperature necessary for vaporizing the liquid, and when the vaporizer 3 becomes higher than the certain temperature, the electric heater 7 is turned off to stop heating, and this cycle is repeated. Control. Reference numeral 10 denotes a 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. The control unit 9 controls the load detecting means 10 (for example, the water temperature or The combustion is controlled so as to stop in accordance with a temperature detection sensor such as an air temperature or a surface temperature of a heat exchanger. Numeral 12 denotes a calculation unit for calculating the operation stop time.
The controller 9 sets the time obtained by subtracting the time from the first energization by the heating means to the stop of the combustion operation stop cycle from the stop time of the combustion operation stop cycle until the next stop of the heating means 7. Control.

The operation of the above configuration will be described with reference to FIG. When the operation is started, the electric heater 7 is energized to heat the vaporizer 3, and when the temperature thermistor 8 detecting the temperature of the vaporizer 3 outputs a temperature equal to or higher than a certain value, the fuel supplied from the fuel pump 1 through the fuel supply pipe 2 is supplied. The primary air for combustion supplied from the combustion fan 4 through the duct 5 is supplied to the carburetor 3. In the carburetor 3, the supplied fuel evaporates and is uniformly mixed with the air, and flows into the combustion unit 6 communicating with the carburetor 3. The combustion unit 6 ignites by ignition means (not shown) to form a combustion flame. Utilizing this combustion heat, heat is transmitted to the heat exchanger 11 through which the object to be heated flows. on the other hand,
The electric heater 7 stops energization. Then, the control unit 9 receives a signal from the load detecting means 10 (for example, a temperature detecting sensor such as a water temperature or an air temperature as a body to be heated, a surface temperature of a heat exchanger, etc.), and performs combustion in accordance with combustion heat and its load. The fuel pump 1 and the combustion fan 4 are controlled to stop the operation. Then, the operation stop time is calculated by the calculation unit 12, and the calculation unit 1
By the output of 2, the control unit 9 subtracts the time from the first energization by the heating means 7 to the stop of the combustion operation stop cycle from the stop time of the combustion operation stop cycle to the time until the next stop of the electric heater 7. To control.

That is, the time from the stop time of the combustion operation stop cycle to the stop of the first energization by the heating means 7 (the vaporizer 3 heated by the electric heater 7 is kept at a constant temperature necessary for vaporizing the liquid fuel. The time required to raise the temperature of the vaporizer 3 by the heater 7 is estimated by subtracting the remaining time from the time until the temperature of the vaporizer 3 is reduced to the time until the next stop of the electric heater 7. . When the control unit 9 detects the load of the combustion heat by energizing the heater 7 earlier than the combustion start time (the time required for the temperature to rise) in advance, the combustion can be started immediately when the combustion operation starts. . As a result, the load
When this fluctuation is large and the load calorie and combustion heat are
And the shutdown of combustion increases, and the fluctuation range
Expand significantly. At this time, the combustion is stopped and restarted.
Is the value calculated and predicted from the increase / decrease tendency of the cycle time to be rotated?
From the first energization of the heating means to the stop
The subtraction is calculated by the calculation unit 12, and this value is calculated from the next combustion stop.
Reactivate the cycle time to make it more agile
Can respond. Therefore, there is no delay due to the heat capacity of the carburetor 3, and the control unit 9 matches the output of the load detection unit 10.
Then, the combustion operation starts immediately, and the heating temperature or the hot water supply temperature responds to the load detection means 10 to be in a comfortable state.

Further, by this, the heating means 7 is energized only for the time necessary for combustion, and the load can be optimally controlled, thereby saving power and energy. In addition, the calculation unit 12 that calculates the output of the load detection means 10 subtracts the time from the first energization by the electric heater 7 to the stop according to the value calculated and predicted from the tendency of the stop time of the combustion stop cycle. Then, by setting the time from the next energization to the stop, the load fluctuates greatly, and when the load of the combustion heat is detected by the control unit 9 even when the stop time greatly changes, the combustion operation is started. Combustion can be started immediately. Therefore, there is no delay due to the heat capacity of the carburetor, the control unit 9 immediately starts the operation of combustion in accordance with the output of the load detecting means 10, and the heating temperature or the hot water supply temperature responds to the load detecting means 10 to provide comfortable operation. State.

When the load increases or decreases little by little, when the load decreases, the above method is applied. When the load increases, in the above method, the heating means operates quickly, the state in which the vaporizer is kept at a high temperature continues, and power consumption increases. Therefore, when the time from when the heating means 7 is stopped to when the combustion is operated by the load detection means 10 is positive, this time is added to the time from the next energization to the stop, so that the combustion device The start of operation and the temperature rise of the vaporizer can coincide.

[0013]

As described above, the present invention relates to a carburetor coupled to a liquid fuel supply unit and a combustion air supply unit and connected to a combustion unit, a heating unit and a temperature detection unit provided in the carburetor, energization of said heating means in response to the output of the combustion the temperature sensing means, to control the stop, and a control unit for operating stop combustion by the load detecting means of the combustion unit, and a calculator for calculating the downtime Prepared, said
The control unit controls the load detection unit based on the output of the arithmetic unit.
From the cycle time to restart operation from combustion stop,
Subtract the time from the first energization of the heating means to the stop
The calculated time is calculated by the calculation unit, and this value is
Control the heating means as a cycle time
And restart the cycle from the combustion stop.
From the value calculated and predicted from the time increase / decrease trend, the heating means
The subtraction of the time from the first energization to the stop is performed by the arithmetic unit.
And calculate this value from the next combustion stop.
Since the cycle time is used, the following effects can be obtained.

(1) It is possible to predict the time required for raising the temperature of the vaporizer by the heater, to make it possible to turn on the heater in advance of the combustion start time, and to detect the load of combustion heat by the control unit. The combustion can be started immediately upon entering the combustion operation.

(2) The heating means is energized only for the time necessary for combustion, and can optimally control the load, thereby saving power and energy.

(3) Even when the load greatly fluctuates and the stop time greatly changes, it is possible to accurately cope with this, and there is no delay due to the heat capacity of the vaporizer. Combustion can be started immediately after the operation starts.

[Brief description of the drawings]

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

FIG. 2 (a) is an operation cycle diagram of the same device. FIG. 2 (b) is an operation cycle diagram of a conventional device.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel pump 3 Vaporizer 4 Combustion fan 6 Combustion part 7 Electric heater 8 Temperature thermistor 9 Control part 10 Load detection means 12 Operation part

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiro Ohama 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-4-64815 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) F23N 5/02 342 F23N 5/02 350 F23N 5/14

Claims (2)

(57) [Claims] 1. A carburetor coupled to a liquid fuel supply unit and a combustion air supply unit and connected to a combustion unit, a heating unit and a temperature detection unit provided in the carburetor, and an output of the temperature detection unit during combustion. A control unit for controlling the energization and stop of the heating means in response thereto, and stopping the operation of the combustion by the load detection means of the combustion unit; and a calculation unit for calculating the operation stop time , wherein the control unit is configured to control the calculation unit. Depending on the output of
The operation is restarted after the combustion is stopped by the load detecting means.
From the first energization of the heating means from the cycle time
The arithmetic unit calculates the time obtained by subtracting the time until the calculation,
Cycle time for restarting this value from the next combustion stop
The heating means is controlled as
Calculate and predict from the increase / decrease trend of cycle time
From the first energization of the heating means to the stop
The subtraction of time is calculated by the calculation unit, and this value is calculated for the next combustion stop.
A liquid fuel combustion device with a cycle time of restarting from stop . 2. Load detection after stopping the energization of the heating means.
When the time until the operation of combustion by means is positive
Adds this time to the time from the next energization to the stop
The liquid fuel combustion device according to claim 1.