JP2000304274A - Kerosene heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a kerosene heater, whose combustion will not be stopped even when an instantaneous service interruption is generated. SOLUTION: A kerosene heater is provided with an evaporator 7, evaporating liquid fuel, a nozzle 8, supplying fuel gas to the evaporator 7, and a solenoid 10, sliding a needle, closing the nozzle 8 by a spring 20, selectively against the spring 20 to open the nozzle. Upon starting, a high voltage is impressed on the solenoid 10 to open the nozzle 8, and a low voltage is impressed to retain the opening of the nozzle 8 upon stationary operation, in which the nozzle 8 is opened once, while the high voltage, impressed upon starting, is impressed temporarily upon re-starting after an instantaneous service interruption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil heating apparatus for vaporizing and burning a liquid fuel.

[0002]

2. Description of the Related Art An open-type oil fan heater of an oil heating apparatus has a structure as shown in FIGS. FIG. 7 is a schematic view of a liquid fuel combustion device in an open type oil fan heater. The liquid fuel in the refueling tank 12 accumulates in the oil pan 6, is sucked up by the electromagnetic pump 2 attached to the oil pan 6, and is sent to the vaporizer 7. A heater (not shown) is attached to the vaporizer 7, and the vaporizer 7 is heated to a high temperature by the heater. Therefore, the liquid fuel fed into the vaporizer 7 is gasified and becomes a fuel gas, and is ejected from the nozzle 8 toward the inside of the burner 13. Burner 1
Inside 3, the primary air is sucked by the ejector effect at the small diameter portion of the mixing pipe 15, and the fuel gas mixed with the primary air is sent to the burner flame port 14 integrated with the mixing pipe 15, It burns here.

FIG. 6 is a side sectional view showing a schematic configuration of an open type oil fan heater main body. Burner 1 as above
The high-temperature burned exhaust gas burned at the burner port 14 of the third combustion chamber 3 is exhausted to the outside of the combustion chamber 3 from the opening at the upper part of the combustion chamber 3 by a draft effect of the convection blower 9 attached to the apparatus main body 1, After being mixed with the room air taken in by the convection blower 9, the air is sent into the room as warm air from a warm air outlet. 4 is a burner box.

FIG. 8 is a schematic sectional view of a vaporizer and a solenoid for controlling opening and closing of a nozzle of the vaporizer. A solenoid 10 is mounted on the vaporizer 7 for vaporizing the liquid fuel, and a movable piece 18 slid by the solenoid 10.
Is connected via a needle joint 17 to a needle 16 that opens and closes the opening of the nozzle 8, and between the movable piece 18 and the suction piece 19 of the solenoid 10, the nozzle 16 is moved by the needle 16 when the solenoid 10 is not energized. A spring 20 for urging the movable piece 18 so as to close the opening 8 is provided.

Accordingly, when the solenoid 10 is energized, the movable piece 18 slides against the pressing force of the spring 20,
The needle 16 is slid to the right to open the opening of the nozzle 8, and the fuel gas can be ejected. In this case, the suction force of the movable piece 18 at the time of activation to the solenoid 10 requires a suction force of about 60 N. However, in a state where the suction state is once held after suction, a voltage for generating a holding force of about 20 N is required. Since it is only necessary to apply the voltage, the solenoid 10 is a short-time rated specification product that can apply a high starting voltage for a short time at the time of starting.

[0006]

In the above-mentioned conventional oil heating apparatus, when an instantaneous power failure occurs during operation, the solenoid is turned off even though the microcomputer circuit for controlling the solenoid keeps operating. , And the nozzle outlet is closed by the action of the spring. Even if the energization is started after the end of the momentary power failure, only a low voltage for generating the above-described holding force is applied to the solenoid, and a high voltage at the time of starting necessary for attracting the movable piece is not applied. Therefore, the movable piece cannot be adsorbed on the suction piece, and the ejection port of the nozzle remains closed by the needle. Therefore, the vaporized fuel gas is not ejected from the ejection port of the nozzle into the burner, resulting in a misfire state.

As a solution to these problems, it is conceivable to connect a capacitor having an extremely large capacity between both terminals of the solenoid. However, a space for installing the capacitor is required, which is disadvantageous in terms of cost. There is.

The present invention has been made in view of the above problems, and has as its object to provide an oil heating apparatus capable of smoothly performing combustion when returning from an instantaneous power failure.

[0009]

In order to solve the above-mentioned problems, the petroleum heating apparatus according to the present invention comprises a vaporizer for vaporizing liquid fuel and a needle for opening and closing a nozzle of the vaporizer. An elastic body that presses the needle against the nozzle so as to close the ejection port of the nozzle with the needle, and a solenoid that moves with the needle and controls opening and closing of the nozzle are provided. Applying a first voltage for moving the needle against the urging force of the elastic body, and holding the needle in an open state against the urging force of the elastic body during normal operation; In a petroleum heating appliance to which a second voltage lower than the first voltage is applied, the first voltage is applied to the solenoid when returning after an instantaneous power failure. .

(Operation) Accordingly, at the time of starting, the first voltage (starting voltage) is applied to the solenoid to move the needle against the urging force of the elastic body. As a result, the ejection port of the nozzle closed by the needle is opened, and the fuel gas obtained by vaporizing the liquid fuel by the vaporizer is ejected from the nozzle toward the burner to start combustion. After the start of combustion, the voltage applied to the solenoid is switched to the second voltage (holding voltage), and the needle is held at the holding position where the nozzle outlet is opened against the urging force of the elastic body.

When an instantaneous power failure occurs, the control circuit controlled by the microcomputer or the like continues to operate by the power charged in the capacitor, but the application of the voltage to the solenoid is cut off. The needle is closed by the movement of the needle by the urging force, and the combustion operation is stopped. When the instantaneous power failure is restored, the same first voltage (starting voltage) as at the time of starting is applied to the solenoid. Therefore, the needle can be moved against the urging force of the elastic body, and the ejection port of the nozzle can be opened to restart combustion.

Further, the oil heating apparatus of the present invention is characterized in that
In, a vaporizer for vaporizing the liquid fuel, a needle for opening and closing the nozzle of the vaporizer, and an elastic body for pressing the needle against the nozzle so as to close the nozzle of the nozzle with the needle, A solenoid for moving the needle and controlling the opening and closing of the nozzle is provided.
At the time of activation, a first voltage for moving the needle against the urging force of the elastic body is applied, and at the time of steady operation, the needle is opened against the urging force of the elastic body to open the nozzle outlet. Hold a second voltage lower than the first voltage
Wherein the first voltage is applied to the solenoid before returning after an instantaneous power failure.

(Operation) Therefore, when an instantaneous power failure occurs, the application of voltage to the solenoid is cut off, so that the ejection port of the nozzle is closed by the movement of the needle due to the repulsive force of the elastic body.
Although the combustion operation is stopped, the control circuit controlled by the microcomputer or the like continues the operation by the electric power charged in the capacitor. When an instantaneous power failure occurs, the control circuit can control the solenoid to apply the first voltage to the solenoid even before recovery from the instantaneous power failure. Thereby, when the instantaneous power failure recovers, the solenoid has the same first voltage (starting voltage) as that at the time of starting.
Is applied. Therefore, the needle can be moved against the urging force of the elastic body, and the ejection port of the nozzle can be opened to restart combustion.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. The appearance configuration of the oil heating equipment according to the present invention is the same as that shown in FIGS.
The description is omitted because it is substantially the same. FIG. 1 is a block diagram of a control circuit for controlling the opening and closing of a nozzle of an oil heating apparatus. This control circuit switches an applied voltage to the microcomputer 22 and an applied voltage to the solenoid 10 shown in FIGS. 7 and 8. 32. The microcomputer 22 includes an instantaneous power failure detection circuit 27 for detecting an instantaneous power failure of the power supply, and a 50 Hz or 6 Hz
A power frequency detection circuit for detecting a power frequency of 0 Hz;
A detection circuit 29 for detecting the power supply voltage waveform and the presence or absence of the frequency based on the detection outputs of the instantaneous power failure detection circuit 27 and the power supply frequency detection circuit 28, and determining the presence or absence of the power supply voltage waveform based on the detection output of the waveform detection circuit Waveform determination circuit 30
And a control unit 31 that controls the application of voltage to the solenoid 10 based on the output of the waveform determination circuit 30.

FIG. 2 is a circuit diagram showing an embodiment of a control circuit used in the oil heating equipment of the present invention. In this circuit diagram, reference numeral 35 denotes a commercial AC power supply, and a primary side of a power supply transformer 34 connected to the commercial power supply is provided with the solenoid 10
And the microcomputer 22 is connected to the solenoid 10.
And an applied voltage switching circuit 32 for selectively applying a high voltage for startup (for example, 100 V) and a low voltage for holding (for example, 20 V) with the output of (1). A rectifier circuit 36 and a power supply clock circuit 37 are provided on the secondary side of the power supply transformer 34, and a 50 Hz or 60 Hz power supply clock signal V of a rectangular wave derived from the power supply clock circuit 37 and having a shaped waveform.
₃₇ is input to the microcomputer 22. The microcomputer 22 detects whether instantaneous power failure or the power source clock signal V ₃₇ input. Then, in the case of an instantaneous power failure, the applied voltage switching circuit 32 supplies the solenoid 10 with the same high voltage as the high voltage at the time of starting, draws the needle 16, opens the nozzle 8, and starts the injection of fuel gas. Then, the ignition at the burner burner port 14 is detected by the frame sensor 11, and the supply voltage to the solenoid 10 is switched to a low voltage for holding, and the original steady state is returned.

During operation in a steady state without an instantaneous power failure, the microcomputer 22 controls the applied voltage switching circuit 32 so as to supply a low voltage for holding to the solenoid 10,
The nozzle 8 is kept open to continue combustion.

Next, the combustion operation of the oil heating equipment using the control circuits shown in FIGS. 1 and 2 will be described in more detail. The vaporizer 7 of the oil heating equipment is heated to a high temperature by a heater (not shown), and gasifies the fed liquid fuel. The fuel gas gasified here is ejected from the nozzle 8 toward the inside of the burner 13, and the primary gas is sucked by the ejector effect at the small diameter portion of the mixing tube 15 inside the burner 13, and the inside of the mixing tube 15 is sucked. And mixed here. A ceramic ignition heater (not shown) provided on the burner flame 14 is provided with a microcomputer 22.
Red heat according to a command from the burner, and ignites and burns the combustion gas ejected from the burner flame port 14. The burned combustion flame is detected by the flame sensor 11 to check the combustion state at all times.

In the control circuit shown in FIG. 1, reference numeral 32 denotes an applied voltage switching circuit for switching a voltage applied to the solenoid 10 under the control of the microcomputer 22. The applied voltage switching circuit 32 turns the solenoid 10 on and off, and turns the needle 16 connected to the solenoid 10 on and off. Is driven to switch the vaporized gas to the burner 13 side or the oil pan 6 side.

Next, the operation in a normal use state will be described. When the solenoid 10 is turned off, the movable piece 18 is opened, and the movable piece 18 is connected to the needle joint 1.
The needle connected by 7 closes the nozzle 8 by the spring 20. Therefore, the vaporized fuel gas is supplied to the burner 13
It cannot be ejected to the side, and is returned to the oil pan 6 via the return pipe 21. When a high voltage at the time of starting is applied to the solenoid 10, the solenoid 10 is turned on, the movable piece 18 is in the suction state, the needle 16 connected to the movable piece 18 by the needle joint 17 is pulled, and the nozzle 8 is opened. Therefore, the vaporized fuel gas is ejected from the ejection port of the nozzle 8 toward the burner 13 and burns.

In this case, the output terminal of the microcomputer 22 becomes "High", the output of the driver 23 becomes "Low", and the relays RY1 (24), RY2
Since (25) is turned ON, AC is applied to the solenoid 10.
A full-wave rectified voltage of 100 V is applied, and the suction piece 19 sucks the movable piece 18.

When the solenoid 10 is turned on, the suction piece 19 sucks the movable piece 18. However, if tar or the like adheres to the nozzle 8 of the vaporizer 7, the suction is increased to about 60N, which is higher than normal. It is necessary to apply a voltage that generates a force. In order to cope with such a situation, according to the present invention, as shown in the control circuit of FIG.
Is turned on, a full-wave rectified voltage of 100 V AC required to generate a suction force of about 60 N is applied to the solenoid 10. When about one second elapses after the suction force and the suction of the movable piece 18 by the suction piece 19 is stabilized, the suction force by the solenoid 10 is sufficient with a holding force of about 20N. Therefore, in this state, the relay 25 is turned off and the relay 24 is turned on by the control circuit, and the solenoid 10 is applied with a low-voltage AC20V full-wave rectified voltage that generates a holding force of about 20N. As described above, a high voltage for a short time is applied to the solenoid 10 only at the time of starting from OFF to ON, and when suction is in a steady state, a low applied voltage for generating a holding force is sufficient. A coil with a short-time rated coil specification can be used.

Next, an operation when an instantaneous power failure occurs during use will be described. First, the AC voltage in use is supplied to the power supply clock circuit 37 as shown in FIG. Then, a power supply clock signal V ₃₇ composed of a rectangular wave having a frequency of 50 Hz or 60 Hz as shown in FIG. 3 obtained by half-wave rectifying the AC waveform on the secondary side of the power transformer 34 by the diode 33 and shaping the waveform by the transistor 26 is obtained. Derive. The power supply clock signal V ₃₇ is input to the microcomputer 22, the power supply frequency is detected by the power supply frequency detection circuit 28, and the power supply frequency is confirmed by the waveform detection circuit 29.

[0023] instantaneous power failure occurs, the power supply clock signal V ₃₇ consisting rectangular wave as shown in FIG. 4 is ceased while the instantaneous power failure detection circuit 27 of the microcomputer 22 shown in FIG. 1 detects this. When the instantaneous power failure is released, the waveform determination circuit 30 detects this and outputs it to the control unit 31, and the control unit 31 applies a suction force of about 60 N to the applied voltage switching circuit 32 to the solenoid 10. A command is issued to apply a full-wave rectified voltage of 100 VAC required for generation. As a result, the output terminal of the microcomputer 22 shown in FIG. 2 is set to "High", the output of the driver 23 is set to "Low", and the relays 24 and 25 are turned on. When the two relays 24 and 25 are turned on, the applied voltage switching circuit 32 shown in FIGS. 1 and 2 applies a full-wave rectified voltage of 100 V AC required to generate a suction force of about 60 N to the solenoid 10, and The piece 19 sucks the movable piece 18 to open the nozzle 8 and restarts the combustion of the fuel gas. Therefore, even if the power is re-energized after an instantaneous power failure as in the conventional example shown in FIG. 5, only a voltage for generating a holding force of about 20 N is applied to the solenoid 10, so that the nozzle 8 of the vaporizer 7 cannot be opened, The problem of misfiring can be avoided and the nozzle once closed can be reopened to continue normal combustion without re-operation.

Further, when an instantaneous power failure occurs, AC is applied to the solenoid 10.
After about 1 second has passed after the 100 V full-wave rectified voltage has been applied, the nozzle 8 is opened again and then becomes a stable open state, so the control unit 31 of the microcomputer 22 turns on the relay 24 to the applied voltage switching circuit 32. A signal for turning off the relay 25 is supplied. As a result, the solenoid 10
, A full-wave rectified voltage of AC 20 V that generates a holding force of about 20 N is applied, the suction valve 19 is in a holding state in which the movable piece 18 is sucked, and the nozzle 8 is kept open.

Further, even when an instantaneous power failure occurs, the microcomputer 22 continues to operate with the electric power charged in the capacitor. By utilizing this fact, the control unit 31 applies 60 N to the applied voltage switching circuit 32 to the solenoid 10 even before the recovery when an instantaneous power failure occurs.
Voltage AC100 required to generate a certain level of suction force
A command to apply a full-wave rectified voltage of V may be issued. As a result, when power is supplied again after an instantaneous power failure, the normally closed nozzle can be reopened and normal combustion can be continued without re-operation.

[0026]

According to the first aspect of the present invention, as described above, the voltage applied to the solenoid at the time of restarting from an instantaneous power failure is changed to the applied voltage at the time of starting, and the voltage applied to the solenoid at the time when restarting is stabilized. Is switched to the holding voltage, so that restart after an instantaneous power failure can be performed smoothly without causing a misfire state, normal usage can be continued without re-operation and use The rating of the solenoid can be suppressed.

According to a second aspect of the present invention, even if an instantaneous power failure occurs, the control circuit continues to operate with the electric power charged in the capacitor, so that the first voltage is applied to the solenoid before returning after the instantaneous power failure. Control to apply. Therefore, restart after an instantaneous power failure can be smoothly performed without causing a misfire state.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control circuit according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a drive circuit according to the embodiment of the present invention.

FIG. 3 is a signal waveform diagram of a main part in FIG.

FIG. 4 is a signal waveform diagram of a main part in FIG.

FIG. 5 is a signal waveform diagram of a main part in a conventional example.

FIG. 6 is a side sectional view showing the overall schematic configuration in the embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a liquid fuel combustion device according to an embodiment of the present invention.

FIG. 8 is a schematic configuration diagram of a main part of the liquid fuel combustion device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Device main body 2 Electromagnetic pump 3 Combustion chamber 4 Burner box 6 Oil pan 7 Vaporizer 8 Nozzle 9 Convection blower 10 Solenoid 11 Frame sensor 12 Oil tank 13 Burner 14 Burner flame opening 15 Mixing pipe 16 Needle 17 Needle joint 18 Movable piece 19 Suction piece 20 Spring 21 Return pipe 22 Microcomputer 23 Driver 24, 25 Relay 26 Transistor 27 Momentary power failure detection circuit 28 Power supply frequency detection circuit 29 Waveform detection circuit 30 Waveform judgment circuit 31 Control unit 32 Applied voltage switching circuit 33 Diode 34 Power supply transformer 35 AC power supply 36 Rectifier circuit 37 Power supply clock circuit

Claims (2)

[Claims] 1. A vaporizer for vaporizing a liquid fuel,
A needle that opens and closes the nozzle of the vaporizer, an elastic body that presses the needle against the nozzle so as to close the nozzle of the nozzle with the needle, and a solenoid that moves the needle and controls the opening and closing of the nozzle And applying a first voltage to the solenoid at the time of activation to move the needle against the urging force of the elastic body, and at the time of steady operation, to apply the first voltage to the nozzle against the urging force of the elastic body. In a petroleum heating appliance configured to apply a second voltage lower than the first voltage that keeps the ejection port of the fuel cell in an open state, the first voltage is applied to the solenoid at the time of return after an instantaneous power failure. Oil heating equipment characterized by the following. 2. A vaporizer for vaporizing a liquid fuel,
A needle that opens and closes the nozzle of the vaporizer, an elastic body that presses the needle against the nozzle so as to close the nozzle of the nozzle with the needle, and a solenoid that moves the needle and controls the opening and closing of the nozzle And applying a first voltage to the solenoid at the time of activation to move the needle against the urging force of the elastic body, and at the time of steady operation, to apply the first voltage to the nozzle against the urging force of the elastic body. In a petroleum heating apparatus configured to apply a second voltage lower than the first voltage that keeps the ejection port of the fuel cell in an open state, the first voltage is applied to the solenoid before returning after an instantaneous power failure. Oil heating equipment characterized in that: