JPH10318536A - Liquid fuel burner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress odor by providing an air supply controller for reducing the combustion air supply to a carburetor by operating a shutter disposed in the upstream of a combustion fan for a specified time during the firing operation thereby reducing production of unburnt gas at the time of firing. SOLUTION: When an operation switch is turned on, a carburetion heater 24 is conducted and a decision is made whether the temperature of a carburetor 35 reached a level suitable for firing operation. It the answer is YES, a combustion fan 27 is driven to introduce the outer air through an intake port 45 into a fan case 30 thence supplying the outer air, as combustion air, to the carburetor 35. Upon elapsing a specified time, a decision is made whether the r.p.m. of a burner motor 31 detected through am r.p.m. sensor reaches a specified level and if the answer is YES, firing operation is performed and the solenoid coil 42 of a shutter 40 is conducted to close the intake port 45 with a closing plate 41 Consequently, the outer air is sucked only through the vent of the closing plate 41 and combustion air supply to the carburetor 35 is reduced.

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 such as a petroleum fan heater or a forced supply / exhaust type hot air heater for vaporizing and burning liquid fuel in a vaporizer. The present invention relates to a liquid fuel combustion device capable of reducing the smell of water.

[0002]

2. Description of the Related Art Conventionally, the ignition operation of a liquid fuel combustion system of this type is controlled by a liquid fuel supply amount (air amount) corresponding to an air flow (air flow) as disclosed in Japanese Patent Application Laid-Open No. 57-47126. As disclosed in Japanese Patent Application Laid-Open No. Sho 62-56707, the amount of air and the amount of fuel are balanced and mixed and the amount of combustion (air-fuel ratio) is "weak". The mainstream control was to ignite slowly in a low state such as "combustion" or "weak combustion" to ensure ignition.

In order to improve the ignition performance at the time of ignition, the fuel amount (specifically, the combustion amount of "strong combustion" or "medium combustion") is increased, for example, as disclosed in JP-A-2-23.
As disclosed in Japanese Patent No. 8251, a method of performing an ignition operation with a fuel amount obtained by mixing air and fuel in a balanced state has been widely adopted.

[0004]

However, the unburned portion of the mixed gas at the time of ignition (hereinafter referred to as unburned gas)
Is generated, and this unburned gas is discharged outside the body of the liquid fuel combustion device and smells. In addition, it takes a little time (less than one second) from when the spark plug sparks at the time of ignition to produce a fire for ignition to completion of the fire transfer to the entire flame forming portion such as the burner head. The flame rises when this fire transfer is completed, but at this time, the flame flickers in an unstable state due to the generation of unburned gas. Furthermore, even when air is blown from the convection blower during the ignition operation, the flame is disturbed or the fire is hardly transferred, so that the ignitability deteriorates and unburned gas is easily generated.

[0005] In view of the above circumstances, an object of the present invention is to provide a liquid fuel combustion device capable of reducing the amount of unburned gas generated during ignition as much as possible to reduce odor.

[0006]

According to the present invention, the mixing ratio (air-fuel ratio) of the mixed gas and the injection speed of the mixed gas from the flame forming section are the largest among the various factors which influence the generation amount of the unburned gas. Focused on the effects.

That is, the present invention provides a vaporizer for vaporizing liquid fuel, a fuel supply device for supplying liquid fuel to the vaporizer, a combustion blower for supplying combustion air to the vaporizer, and a combustion blower. A shutter device provided further upstream, a flame forming portion that is supplied with a mixed gas of gaseous fuel and combustion air vaporized by the carburetor and is ignited by an igniter to form a flame; In a liquid fuel combustion device comprising a combustion blower and a combustion control device for controlling the operation of an ignition device, the supply amount of combustion air to the carburetor by operating the shutter device for a predetermined time during the ignition operation Is provided by providing an air volume control device for controlling so as to reduce the air flow.

Further, according to the present invention, the shutter device includes a closing plate having a ventilation hole, a solenoid coil for driving the closing plate to close the intake port, and urging the closing plate to close the intake port. The spring is configured to be opened.

[0009]

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

FIG. 1 is a perspective view showing one embodiment of a petroleum fan heater as a liquid fuel combustion device according to the present invention, and FIG.
3 is a control block diagram of the oil fan heater shown in FIG. 1, and FIG.
FIG. 4 is a flowchart showing an example of a combustion control program, FIG. 4 is a flowchart showing an example of an air flow control program, FIG. 5 is a time chart showing a general change of signals in an ignition operation sequence, and FIG. It is sectional drawing which shows a combustion part.

As shown in FIG. 1, an oil fan heater H as a liquid fuel combustion device according to the present invention has an outer case 1
And a warm air outlet 2 is formed at the front of the outer case 1. A cover 3 is provided on the upper surface of the outer case 1.
The cover 3 is opened so that a cartridge tank (not shown) can be taken in and out. Further, an operation panel 4 is provided on the upper surface of the outer case 1 as an operation section. The operation panel 4 includes operation means such as switches for instructing the operation of the oil fan heater H by control means described later, and a liquid crystal display. Display means such as a display unit is provided.

The fan case 3 is provided in the outer case 1.
0 is installed behind the hot air outlet 2, and a combustion blower 27 is mounted in the fan case 30 as shown in FIG. 6. The combustion blower 27 includes a burner motor 31 and a turbo fan 32 mounted on a rotating shaft thereof. A burner stand 33 is mounted above the fan case 30, and a vaporizer 35 is mounted on the burner stand 33. Vaporizer 35
Has a built-in vaporizer heater 24 such as a sheath heater, and a burner head 36 is mounted on a vaporizer 35 as a flame forming unit. Further, the frame sensor 20 is installed near the burner head 36, and the ignition plug 25 is installed as an ignition device.

A shutter device 40 is provided on a side surface of the fan case 30. This shutter device 4
0 is a closing plate 41, a solenoid coil 42 and a spring 43
The closing plate 41 is normally provided with a spring 43.
However, when the solenoid coil 42 is energized, the intake port 45 is closed against the elasticity of the spring 43. In addition, since the ventilation hole (not shown) is formed in the closing plate 41, the closing plate 4
Even if 1 closes the intake port 45, the inside and outside communicate with each other through this ventilation hole.

Meanwhile, a control device S is incorporated as a combustion control device and a blower volume control device at a lower rear portion of the oil fan heater H, and the control device S includes a control means 11 as shown in FIG. ing. This control means 11
Is composed of a microcomputer having a timer, a ROM and a RAM as storage means (hereinafter simply referred to as a microcomputer), and the microcomputer outputs a control signal for controlling operations of various loads based on an input signal. I do. Further, the control means 11 has an EEPR through a signal line.
The OM 12 is connected as a writable storage means at any time. In FIG. 2, the EEPROM 12 is connected to the control unit 1.
Although it is expressed as if it is separate from the device 1, this is not limited to a separate device, and the EEPROM 12 may be incorporated in the control means 11.

On the input side of the control means 11, various switches provided on the operation panel 4 are connected.
These switches include a run-on switch 13, a run-off switch 14, a second-speed ignition switch 15, a filter switch 16, a temperature control switch 17, and a time setting switch 18.

Further, various sensors are connected to the input side of the control means 11. These sensors include a burner thermistor 19, the frame sensor 20, a rotation speed sensor 21, a liquid level sensor 22, and a room temperature sensor 23. is there.

On the other hand, various electric parts are connected to the output side of the control means 11, such as the vaporizing heater 24, the spark plug 25, the electromagnetic pump 26 as a fuel supply device, the combustion Fan 27 and convection fan 28.

Since the oil fan heater H has the above configuration, the combustion operation of the oil fan heater H is executed by the control device S based on a combustion control program shown in FIG. 3 as described below. .

First, in step S1, when the operation input switch 13 for instructing the start of operation is turned on, step S2 is executed.
Then, the operation lamp is turned on or the character of the operation mode is displayed on the liquid crystal display section. In step S3, the energization of the vaporization heater 24 is started. In step S4, the temperature of the vaporizer 35 is adjusted to a temperature suitable for the ignition operation (for example, 250-270 ° C temperature zone)
It is determined whether or not this is the case, and the energization control of the vaporization heater 24 is continued until the temperature reaches an appropriate temperature. When the temperature reaches the appropriate temperature, a drive signal is output to the combustion blower 27 in step S5. Then, the burner motor 31 of the combustion blower 27 is driven, and the turbo fan 32 rotates. As a result, outside air (that is, room air) is drawn into the fan case 30 through the intake port 45 and is supplied to the carburetor 35 as combustion air at a predetermined blowing rate.

Next, at step S6, it is determined whether or not the rotation speed of the burner motor 31 detected by the rotation speed sensor 21 has reached a predetermined rotation speed (for example, 1500 rpm) after a certain time has elapsed. If it is determined that the number has reached the number, an ignition operation (details will be described later) is performed in step S7, and it is determined in step S8 whether ignition has been performed based on the flame current detected by the flame sensor 20. Then, it is determined in step S9 whether or not the combustion is normal.

If it is determined in step S8 and step S9 that the fuel is ignited and the combustion is normal, the ignition operation (spark) of the spark plug is stopped in step S10, and the vaporization heater is stopped in step S11. 24 is stopped. Next, in step S12, an automatic change operation of the combustion amount is started to set the combustion mode based on the setting by the temperature control switch 17 or the set room temperature, and in step S1
In step 3, it is determined whether the state of the flame at the set combustion amount is normal based on the flame current detected by the flame sensor 20. As a result, when it is determined that the operation is normal, the operations of step S12 and step S13 are repeated.

On the other hand, as a result of the determination in step S6, if it is determined that the rotation speed has not reached the specified value, the energization of the vaporization heater 24 is stopped in step S14,
In step S15, the operation lamp is blinked or the character of the operation mode on the liquid crystal display is blinked, and in step S16, a symbol (for example, "E6") indicating the rotation speed abnormality of the burner motor 31 is displayed as the abnormality content to notify the abnormality. . In this case, the operation does not shift to the ignition operation until the abnormality is eliminated. Then, in step S17, the operation switch 14 by the user is turned off.
And after the operation of the operation switch 13, the process proceeds to step S 3.
Can return to

If it is determined in step S8 or S9 that ignition is not occurring or combustion is not normal, the ignition trial period (for example, 2
Within 3 seconds), it was determined that the abnormality was not normal flame detection (this is called ignition error).
In step S8, the energization of the vaporization heater 24 is stopped. In step S19, the operation lamp is blinked or the operation mode character on the liquid crystal display is blinked. In step S20, a symbol indicating an ignition error (for example, "E1") is displayed as an abnormality. Is displayed to detect abnormalities. Subsequently, in step S21, the ignition operation of the ignition plug 25 is stopped, in step S22, the fuel supply operation of the electromagnetic pump 26 is stopped, and in step S23, the convection fan 2 is stopped.
In step S24, the drive signal is stopped to stop the combustion blowers 27 in step S24, and the ignition sequence is ended. Then, in step S25, the operation can be returned to step S3 through the operation of the operation switch 14 and the operation switch 13 by the user.

Further, as a result of the determination in step S13,
If it is determined that the ignition is not normal, it is considered that the ignition has occurred but the abnormality has been consumed during the change of the combustion amount (this is called fire extinguishing during the course). Is blinked, and a symbol (for example, “E2”) indicating halfway extinguishing is displayed as the content of the abnormality in step S27 to notify the abnormality. Subsequently, in step S28, the fuel supply operation of the electromagnetic pump 26 is stopped, and in step S29, the convection blower 28 is stopped.
In step S30, the drive signal is stopped to stop the combustion blowers 27, and the combustion amount control sequence is terminated. Then, in step S31, through the operation of the operation switch 14 and the operation switch 13 by the user,
It is possible to return to step S3.

Next, the ignition operation in step S7 will be described in detail with reference to the flowchart of the air flow control program shown in FIG. 4 and the timing chart of the ignition operation sequence shown in FIG.

First, in step S71, the ignition operation of the ignition plug 25 is first started, and at the same time, in step S72.
Then, the solenoid coil 42 is energized to close the intake port 45 with the closing plate 41. Then, the outside air that had been drawn into the fan case 30 through the entire intake port 45 until then,
Since the air is drawn only through the ventilation holes of the closing plate 41, the amount of air drawn into the fan case 30 decreases, and accordingly, the amount of combustion air supplied to the vaporizer 35 also decreases.

Next, the routine proceeds to step S73, in which a fixed time A is set as a delay time, and in step S74, it is determined by a timer whether the fixed time A has elapsed from the start of ignition of the ignition plug 25 as a starting point. . And a certain time A
Is determined to have elapsed, the process proceeds to step S75, and the electromagnetic pump 26 is driven. Then, the vaporizer 35
Kerosene is supplied as liquid fuel.

Thereafter, at step S76, a fixed time B is set as a delay time, and at step S77.
Then, a fixed time C is set as a delay time, and step S
At 78, it is determined by a timer whether or not a predetermined time B has elapsed starting from the time when the electromagnetic pump 26 is driven.

When it is determined that the predetermined time B has elapsed, the flow shifts to step S79, in which the energization of the solenoid coil 42 is stopped to open the intake port 45, and at the same time the ignition operation of the spark plug 25 is stopped. .

Next, in step S710, the electromagnetic pump 2
It is determined by a timer whether or not a predetermined time C has elapsed from the time when the motor 6 is driven. When it is determined that the predetermined time C has elapsed, the process proceeds to step S711, and the convection blower 28 is driven by the predetermined drive. Output a signal. Then, the fan motor of the convection blower 28 is driven, and hot air is blown out from the hot air outlet 2.

As described above, if the intake port 45 is closed in accordance with the ignition operation of the ignition plug 25 at the initial stage of ignition, the amount of combustion air blown to the carburetor 35 is reduced. Is higher than usual, burner head 3
The jetting speed of the mixed gas from No. 6 becomes slow. Therefore, the flame in the burner head 36 does not occur in a lift-like manner but rather spreads over the entire burner head 36, so that the fire in the burner head 36 is performed in a short time and reliably. As a result, the amount of unburned gas generated at the time of ignition is reduced, and the odor caused by the unburned gas is reduced.

[0032]

As described above, according to the present invention, a vaporizer for vaporizing a liquid fuel, a fuel supply device for supplying the liquid fuel to the vaporizer, and a combustion for supplying combustion air to the vaporizer Blower, a shutter device provided upstream of the combustion blower, and a flame that is supplied with a mixed gas of gaseous fuel and combustion air vaporized by the vaporizer and ignited by an ignition device to form a flame. In a liquid fuel combustion device comprising a forming unit and a fuel supply device, a combustion blower and a combustion control device for controlling the operation of an ignition device, the carburetor is operated by operating the shutter device for a predetermined time during an ignition operation. Since the air supply control device that controls the supply amount of the combustion air to the air supply device is configured to be reduced, the shutter device is operated by the air supply amount control device only at the initial stage of ignition. Since the mixing ratio of the fuel can be increased from the normal time during the fire operation and the jetting speed of the mixed gas from the flame forming section can be suppressed, the flame in the flame forming section is generated so as to spread over the entire flame forming section, and the flame forming section generates Can be performed in a short time and reliably, so that generation of unburned gas at the time of ignition can be suppressed and odor can be reduced.

According to the present invention, the shutter device includes a closing plate having a ventilation hole, a solenoid coil for driving the closing plate to close the intake port, and urging the closing plate to generate the intake air. It is composed of a spring that opens the port, so that only during the initial stage of ignition, the solenoid coil is energized by the air flow control device to close the intake port, so that the fuel mixture ratio during ignition operation is higher than normal. In addition to the above, since the jet velocity of the mixed gas from the flame forming section can be suppressed, the flame in the flame forming section is generated so as to spread over the entire flame forming section, and the fire in the flame forming section is performed in a short time and reliably. Therefore, generation of unburned gas at the time of ignition can be suppressed to reduce odor.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of an oil fan heater as a liquid fuel combustion device according to the present invention.

FIG. 2 is a control block diagram of the oil fan heater shown in FIG.

FIG. 3 is a flowchart illustrating an example of a combustion control program.

FIG. 4 is a flowchart illustrating an example of an air volume control program.

FIG. 5 is a time chart showing a schematic change of a signal in an ignition operation sequence.

FIG. 6 is a sectional view showing a combustion section of the oil fan heater shown in FIG.

[Explanation of symbols]

 H: Liquid fuel combustion device (oil fan heater) S: Combustion control device, air flow control device (control device) 11: Control means (microcomputer) 25: Ignition device (spark plug) 26: Fuel supply device (Electromagnetic pump) 27 Blower for combustion 28 Blower for convection 35 Vaporizer 36 Flame forming part (burner head) 40 Shutter device 41 Closing plate 42 Solenoid coil 43 Spring 45 ... Inlet

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Takeshi Osawa 2-5-1-5, Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Takao Arai 2-5-2, Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (2)

[Claims] 1. A vaporizer for vaporizing a liquid fuel, a fuel supply device for supplying the liquid fuel to the vaporizer, a combustion blower for supplying combustion air to the vaporizer, and an upstream of the combustion blower. Provided shutter device, a flame forming unit that is supplied with a mixed gas of gaseous fuel and combustion air vaporized by the vaporizer and ignited by an ignition device to form a flame,
In a liquid fuel combustion device including a fuel supply device, a combustion blower, and a combustion control device for controlling operations of an ignition device, the shutter device is operated only for a predetermined time during an ignition operation to perform combustion for the carburetor. A liquid fuel combustion device, comprising: a blowing amount control device that controls the supply amount of air to decrease. 2. A shutter device comprising: a closing plate having a ventilation hole formed therein; a solenoid coil for driving the closing plate to close the intake port; and a spring for urging the closing plate to open the intake port. The liquid fuel combustion device according to claim 1, comprising: