JP6420595B2 - Combustion device - Google Patents

Description

  The present invention relates to a combustion apparatus that is a heater such as an oil fan heater.

Some heaters, such as oil fan heaters, are configured to extinguish fire when the operation switch is turned off, after switching the supply amount of kerosene to the combustion section to the minimum flow rate and continuing combustion. (For example, refer to Patent Document 1).
In this configuration, after the operation switch is operated, the unburned gas in the combustion section can be burned by continuing the combustion with the minimum heating power.

JP 2006-242521 A

  In the above-described conventional combustion apparatus, when the operation switch is turned off, if a sudden switch is made from a large heating power to a minimum heating power, a large amount of unburned gas is generated. Therefore, the odor due to hydrocarbons contained in the unburned gas May not be sufficiently reduced.

  An object of the present invention is to solve the above-described problems and to provide a combustion apparatus that can sufficiently reduce the odor generated when combustion is stopped.

In order to solve the above-described problems, the present invention provides a combustion unit that burns a mixture of liquid fuel and air, a pump that supplies the liquid fuel to the combustion unit, and a combustion blower that supplies air to the combustion unit. And a control unit that controls the operation of the pump and the blower for combustion. In the control unit, a reference level of the thermal power is set based on the hydrocarbon concentration generated during fire extinguishing. When the control unit receives the combustion stop signal and the thermal power of the combustion unit is greater than the reference level, the control unit receives the stop signal and reaches the first set time. The supply amount of the liquid fuel by the pump and the supply amount of air by the combustion blower are decreased stepwise at the same timing every predetermined time , and the heating power of the combustion unit is reduced to the reference level. ing. If the thermal power of the combustion section is reduced to the reference level before reaching the first set time, the thermal power of the combustion section is maintained at the reference level. When the second set time after the first set time is reached, the supply of the liquid fuel by the pump and the supply of air by the combustion blower are stopped . In addition, when the control unit receives the stop signal and the thermal power of the combustion unit is less than or equal to the reference level, from the time when the stop signal is received until the second set time is reached, The liquid fuel supply amount by the pump and the air supply amount by the combustion blower when the stop signal is received are maintained. When the second set time is reached, the liquid fuel supply by the pump and the air supply by the combustion blower are stopped .

  The reference level of thermal power in the present invention is thermal power that prevents the user from feeling unpleasant about the odor that leaks outside during fire extinguishing. That is, it is a thermal power that generates less unburned gas during fire extinguishing and sufficiently reduces the hydrocarbon concentration in the combustion section.

In the combustion apparatus of the present invention, when the combustion is stopped, the fire is extinguished after the heating power of the combustion section is reduced stepwise. Thus, by reducing the thermal power of the combustion part in stages, the generation of unburned gas due to the reduction in thermal power can be suppressed, and the unburned gas generated little by little can be effectively burned.
Further, in the combustion apparatus of the present invention, the supply amount of air as well as the supply amount of liquid fuel is reduced stepwise, so that abnormal combustion due to excessive supply of fuel or air can be prevented.
Therefore, in the combustion apparatus of the present invention, when the operation is stopped, the odor leaking to the outside can be sufficiently reduced even when burning with a large heating power.

In the above-described combustion apparatus, when the thermal power level of the combustion unit is set in the control unit, the reference level is set to the thermal power level at which the hydrocarbon concentration generated during extinguishing is the lowest among the thermal power levels. Thus, the odor leaking to the outside can be sufficiently reduced.
Note that the thermal power level at which the concentration of hydrocarbons generated at the time of extinction is the smallest is, for example, thermal power when an air-fuel mixture having an air-fuel ratio of approximately 0.885 is burned. With this thermal power, the combustion reaction rate is increased, so that the generation of unburned gas during fire extinguishing is reduced, and the hydrocarbon concentration in the combustion part is the lowest.

  In the combustion apparatus of this invention, when stopping combustion, the odor which leaks outside can fully be reduced, and it can prevent a user feeling unpleasant odor.

It is a side section showing a combustion device concerning an embodiment of the present invention. 1 is a schematic configuration diagram illustrating a combustion apparatus according to an embodiment of the present invention. 6 is a time chart showing control when the thermal power is larger than a reference level when a stop signal is received in the combustion apparatus according to the embodiment of the present invention. 6 is a time chart showing control when the heating power is below a reference level when a stop signal is received in the combustion apparatus according to the embodiment of the present invention. It is the flowchart which showed control of the combustion apparatus which concerns on embodiment of this invention.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, the combustion apparatus 1 of the present embodiment is a heater installed indoors, and is an oil fan heater configured to blow out hot air using kerosene as fuel.

  The combustion apparatus 1 has a box-shaped main body 10. In the main body 10, a combustion unit 20, a fuel tank 30, a pump 40, a combustion blower 50, and a convection blower 60 are accommodated. Furthermore, a control unit 70 that controls the operation of the pump 40, the combustion blower 50, and the convection blower 60 is accommodated in the main body 10.

An air outlet 11 for blowing warm air from the inside of the main body 10 toward the outside is opened on the front surface of the main body 10.
An operation unit 15 is provided in the upper part of the front surface of the main body unit 10. The operation unit 15 is provided with an operation switch 16 (see FIG. 2) for instructing the start and stop of combustion of the combustion apparatus 1, and is provided with various switches for temperature adjustment and a monitor for displaying the operation status. Yes.

  The combustion unit 20 includes a vaporizing cylinder 21 and a burner 22 disposed in the vaporizing cylinder 21, and is configured to burn a mixture of kerosene and air with the burner 22. The vaporizing cylinder 21 is disposed at a position facing the air outlet 11.

The fuel tank 30 is disposed in the lower part of the main body 10 and stores kerosene that is liquid fuel.
The pump 40 is an electromagnetic plunger pump. Kerosene in the fuel tank 30 pumped up by the pump 40 is supplied to the burner 22 through a fuel supply pipe 41.

The combustion blower 50 supplies air to the burner 22. The combustion blower 50 includes a drive motor 51 and a blower fan 52 connected to the output shaft of the drive motor 51.
The blower fan 52 is housed in one end of the blower tube 53. One end of the blower tube 53 is closed, and the opening at the other end is connected to the burner 22. When the blower fan 52 is rotated in the blower pipe 53, air is supplied to the burner 22 through the blower pipe 53.

The convection blower 60 is a blower for blowing the combustion gas of the combustion unit 20 as hot air from the blowout port 11. The convection blower 60 is disposed on the opposite side of the outlet 11 side with respect to the vaporizing cylinder 21.
The convection blower 60 includes a drive motor 61 and a blower fan 62 connected to the output shaft of the drive motor 61.

  In the combustion apparatus 1, kerosene is supplied to the burner 22 by the pump 40, and air is supplied to the burner 22 by the combustion blower 50, and a mixture of kerosene and air is burned by the burner 22. And in the combustion apparatus 1, indoors can be heated by blowing the combustion gas of the combustion part 20 as warm air from the blower outlet 11 with the convection fan 60. FIG.

As shown in FIG. 2, the control unit 70 is a computer having a CPU (Central Processing Unit) and a storage unit 71 (not shown). Control by each means of the control unit 70 is realized by the CPU executing a program stored in advance in the storage unit 71.
The controller 70 is provided with combustion adjusting means 72 for adjusting the heating power of the burner 22 by changing the operating states of the pump 40, the combustion fan 50 and the convection fan 60.

The storage unit 71 stores the amount of kerosene supplied by the pump 40 and the amount of air supplied by the combustion blower 50 for each level of thermal power.
In addition, the storage unit 71 stores a reference level indicating a thermal power that serves as a reference for extinguishing the combustion unit 20.

The reference level of the thermal power is a thermal power that does not make the user feel uncomfortable among the thermal power levels stored in the storage unit 71 and leaks to the outside during fire extinguishing. That is, it is a thermal power in which the generation of unburned gas is reduced during fire extinguishing and the hydrocarbon concentration in the combustion section 20 is sufficiently low.
The reference level of the present embodiment is a thermal power level when an air-fuel mixture having an air-fuel ratio of approximately 0.885 is burned. With this thermal power, the reaction rate of combustion is increased, so that the generation of unburned gas during fire extinguishing is reduced, and the hydrocarbon concentration in the combustion section 20 is the lowest.

  The combustion adjusting means 72 selects the level of thermal power based on the signal received from the operation unit 15, and supplies the kerosene supplied by the pump 40 and the air supplied by the combustion blower 50 so as to achieve the level of thermal power. Adjust. Moreover, the combustion adjustment means 72 is comprised so that the rotation speed of the ventilation fan 62 of the convection blower 60 may be adjusted according to the level of a thermal power.

Next, the control of the control unit 70 when stopping the combustion of the combustion apparatus 1 will be described.
As shown in FIG. 2, when the operation switch 16 of the operation unit 15 is turned off while the combustion unit 20 is burning, a stop signal is transmitted from the operation unit 15 to the combustion adjusting means 72 (FIG. 2). 5 step S1).

  When the combustion adjustment means 72 receives the stop signal, it compares the thermal power of the combustion unit 20 with the thermal power of the reference level stored in advance in the storage unit 71 (step S2 in FIG. 5).

  When the heating power of the combustion unit 20 is greater than the reference level, the combustion adjusting means 72 gradually decreases the amount of kerosene supplied by the pump 40 every predetermined time and supplies air by the combustion blower 50. The amount is reduced stepwise every predetermined time, and the level of thermal power is lowered stepwise every predetermined time (0 to T1 in FIG. 3, step S3 in FIG. 5). At this time, the combustion adjusting means 72 reduces the rotational speed of the blower fan 62 (see FIG. 1) of the convection blower 60 in a stepwise manner, and reduces the wind speed of the warm air blown out from the outlet 11 in a stepwise manner.

In the combustion adjustment means 72 of the present embodiment, the thermal power level is reduced by one step for about one second for a preset period of about eight seconds (0 to T1 in FIG. 3), so that the thermal power level is set as a reference. Reduced to level.
Note that if the heating power reaches the reference level before reaching the set time (T1 in FIG. 3), the combustion adjusting means 72 reduces the heating power at the reference level until the set time (T1 in FIG. 3). Let it be maintained.

  When reaching the set time (T2 in FIG. 3), the combustion adjusting means 72 stops the pump 40 and the combustion blower 50 and stops the combustion of the combustion unit 20 (T2 in FIG. 3, step S4 in FIG. 5). ).

  The combustion adjusting means 72 repeats driving and stopping of the pump 40 at short intervals after stopping the combustion, and the rotation speed before the blower fan 62 (see FIG. 1) of the convection blower 60 receives the stop signal. (T2 to T3 in FIG. 3, step S5 in FIG. 5).

The pump 40 of the present embodiment repeats the supply and stop of kerosene at short intervals, whereby the discharge check valve is pushed open by the plunger, and a part of the kerosene remaining in the oil supply pipe 41 is removed. It is configured to return to the cylinder.
Then, as described above, by repeating the drive and stop of the pump 40 at short intervals, it is possible to prevent kerosene from dripping from the fuel supply pipe 41 and generating odor when the operation of the combustion apparatus 1 is stopped. .

The combustion adjusting means 72 stops the pump 40 when the predetermined time (T3 in FIG. 3) is reached after repeating driving and stopping of the pump 40, and causes the combustion blower 50 to supply air to the burner 22 ( T3 to T4 in FIG. 3, step S6 in FIG.
At this time, the combustion adjustment means 72 is connected to the combustion blower 50 so that the supply amount of air to the combustion unit 20 by the combustion blower 50 is the same as the supply amount before the combustion adjustment means 72 receives the stop signal. The rotation speed of the blower fan 52 (see FIG. 1) is adjusted.

  When the combustion adjusting unit 72 reaches a predetermined time (T4 in FIG. 3) after stopping the pump 40, the combustion adjusting unit 72 stops the combustion blower 50 and the convection blower 60 to stop the operation of the combustion apparatus 1 (FIG. 3 T4, step S7 in FIG. 5).

  On the other hand, when the combustion adjustment means 72 receives the stop signal and the heating power of the combustion unit 20 is below the reference level, the combustion adjustment means 72 drives the pump 40, the combustion blower 50, and the convection blower 60. Until a predetermined time (T2 in FIG. 4) is reached. (0 to T2 in FIG. 4, step S8 in FIG. 5). Thus, from the time when the combustion adjusting means 72 receives the stop signal until the predetermined time (T2 in FIG. 4) is reached, the amount of kerosene supplied by the pump 40 and the amount of air supplied by the combustion blower 50 when the stop signal is received. Supply quantity is maintained.

  When the combustion adjusting means 72 receives a stop signal and reaches a predetermined time (T2 in FIG. 4), the combustion adjusting means 72 stops the pump 40 and the blower 50 for combustion and stops the combustion of the combustion section 20 (T2, FIG. 4). Step S9 in FIG.

In the combustion adjusting means 72, after stopping combustion, the driving and stopping of the pump 40 are repeated at short intervals, and the convection blower 60 is temporarily stopped and restarted (from T2 to T3 in FIG. 4, steps in FIG. 5). S10).
The combustion adjusting means 72 rotates the blower fan 62 (see FIG. 1) of the convection blower 60 at the rotation speed before the combustion adjusting means 72 receives the stop signal.

The combustion adjusting means 72 stops the pump 40 when the predetermined time (T3 in FIG. 3) is reached after repeating driving and stopping of the pump 40, and causes the combustion blower 50 to supply air to the burner 22 ( T3 to T4 in FIG. 4, step S10 in FIG.
At this time, the combustion adjustment means 72 is connected to the combustion blower 50 so that the supply amount of air to the combustion unit 20 by the combustion blower 50 is the same as the supply amount before the combustion adjustment means 72 receives the stop signal. The rotation speed of the blower fan 52 (see FIG. 1) is adjusted.

  When the combustion adjusting means 72 reaches a predetermined time (T4 in FIG. 4) after stopping the pump 40, the combustion adjusting means 72 stops the combustion blower 50 and the convection blower 60 to stop the operation of the combustion apparatus 1 (FIG. 4 T4, step S7 in FIG. 5).

In the combustion apparatus 1 as described above, when the combustion is stopped, the fire power of the combustion unit 20 is gradually reduced and then extinguished (see FIG. 3). Thus, by reducing the thermal power of the combustion unit 20 in stages, the generation of unburned gas due to the reduction in thermal power can be suppressed, and the unburned gas generated little by little can be burned effectively. . In addition, the amount of kerosene supplied and the amount of air supplied are gradually reduced at the same timing, so the timing for reducing the amount of kerosene and air supplied is shifted to prevent abnormal combustion due to excessive supply of fuel or air. be able to. Furthermore, by continuing to drive the convection blower 60, the unburned gas in the combustion unit 20 can be diffused.
Further, since it takes longer to reduce the amount of air supplied by the combustion blower 50 by one step than the time required to reduce the amount of kerosene supplied by the pump 40 by one step, the supply of kerosene and air After a certain amount of time has elapsed since the amount was reduced by one step, the supply amount of kerosene and air is further reduced to reduce the supply amount of air during that predetermined time, thereby supplying kerosene. The amount and the amount of air supply are always appropriate. As a result, it is possible to prevent the decrease in the air supply amount from catching up with the decrease in the kerosene supply amount, resulting in excessive air and abnormal combustion.

  Therefore, the combustion apparatus 1 can sufficiently reduce the odor leaking to the outside even when burning with a large heating power when the operation is stopped, and the user can feel the odor unpleasant. Can be prevented.

  Moreover, in the combustion apparatus 1, when the thermal power of the combustion part 20 is below the reference level, the combustion can be stopped quickly by stopping the pump 40 and the combustion blower 50 after a predetermined time has elapsed. it can.

The embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention.
For example, the combustion adjusting means 72 shown in FIG. 2 reduces the heating power of the combustion unit 20 to the reference level (T2 to T3 in FIG. 3), and then repeats driving and stopping of the pump 40 at short intervals. The state where 40 is stopped may be maintained.

DESCRIPTION OF SYMBOLS 1 Combustion apparatus 10 Main body part 11 Outlet 15 Operation part 16 Actuation switch 20 Combustion part 21 Vaporization cylinder 22 Burner 30 Fuel tank 40 Pump 41 Oil supply pipe 50 Combustion blower 51 Drive motor 52 Blower fan 53 Blower pipe 60 Convection blower 61 Drive Motor 62 Blower fan 70 Control unit 71 Storage unit 72 Combustion adjusting means

Claims (2)

A combustion section for burning a mixture of liquid fuel and air;
A pump for supplying the liquid fuel to the combustion section;
A combustion blower for supplying air to the combustion section;
A control unit that controls the operation of the pump and the blower for combustion, and a combustion device comprising:
In the control unit, a reference level of thermal power is set based on the hydrocarbon concentration generated during fire extinguishing,
The controller is
When the combustion power is larger than the reference level when the combustion stop signal is received,
Between the time when the stop signal is received and the time until the first set time is reached, the supply amount of the liquid fuel by the pump and the supply amount of air by the combustion blower are gradually reduced at the same timing every predetermined time. And reducing the thermal power of the combustion section to the reference level,
If the thermal power of the combustion section has dropped to the reference level before reaching the first set time, the thermal power of the combustion section is maintained at the reference level,
When the second set time after the first set time is reached, the supply of the liquid fuel by the pump and the supply of air by the combustion blower are stopped ,
When the thermal power of the combustion part is below the reference level when the stop signal is received,
From the time when the stop signal is received until the second set time is reached, the supply amount of the liquid fuel by the pump and the supply amount of air by the combustion blower when the stop signal is received are maintained,
When the second set time is reached, the combustion apparatus stops the supply of liquid fuel by the pump and the supply of air by the combustion blower . In the control unit, a thermal power level of the combustion unit is set,
2. The combustion apparatus according to claim 1, wherein the reference level is set to the thermal power level at which a hydrocarbon concentration generated at the time of extinguishing is the smallest among the thermal power levels.

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