JPH07332662A - Combustion device - Google Patents

Abstract

PURPOSE:To provide a combustion device which is capable of reigniting in automatic mode and restarting combustion even when a burner fails to operate under the effect of disturbances, such as wind. CONSTITUTION:In an FF type Fat water heater A, a microcomputer 50, if a flame failure is detected with a flame rod 61, instructs a sparker drive circuit 31, a solenoid drive circuit 110 and a proportional valve drive circuit 131 to start a reignition operation in the case of a small amount of combustion where a combustion fan which feeds combustion air to a gas burner drives below a specified rotary speed.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to combustion devices.

[0002]

2. Description of the Related Art A gas burner to which gas is supplied through a gas safety valve and a gas proportional valve, a sparker for igniting the gas burner, and a combustion air for the burner,
A blower that sucks in outside air, a blower force of the blower, a high voltage applied to the sparker, and a combustion controller that controls the operation of a gas safety valve and a gas proportional valve, and a combustion state of the gas burner is monitored to detect misfire. Then, a combustion monitoring means for closing the gas safety valve to shut off the gas supply to the gas burner,
BACKGROUND ART Conventionally, there is known a hot-air heating device including a convection fan that sucks indoor air, absorbs heat of high-temperature combustion exhaust gas, and blows indoor air heated as hot air into the room.

[0003]

However, the above-mentioned conventional hot air heating device has the following problems. If the gas burner misfires during operation due to wind or the like, the combustion monitoring means closes the gas safety valve to shut off the gas supply to the gas burner, thus ensuring safety. However, since the heating operation is stopped thereafter, the room temperature is lowered and the user feels uncomfortable.

SUMMARY OF THE INVENTION An object of the present invention is to provide a combustion device which automatically re-ignites and restarts combustion even if the burner misfires due to the influence of disturbance such as wind.

[0005]

[Means for Solving the Problems] In order to solve the above problems,
The present invention has the following configurations. (1) A burner to which fuel is supplied through the fuel supply adjusting means, an ignition means for igniting the burner, a combustion for controlling the operation of the ignition means, and adjusting the supply capacity of the fuel supply adjusting means The burner has a control unit and a combustion monitoring unit that monitors the combustion state of the burner and instructs the fuel supply adjustment unit to cut off the fuel supply to the burner when misfire is detected. When the combustion monitoring means detects the misfire of the burner during combustion, the combustion control means performs the reignition operation.

(2) A burner to which fuel is supplied through the fuel supply adjusting means, an ignition means for igniting the burner, and a combustion air to the burner, so that the burner has a specified combustion amount. A blower that is controlled to rotate at a rotation speed that provides an appropriate amount of air, a combustion control unit that controls the operation of the ignition unit, the rotation speed of the blower, and the supply capacity of the fuel supply adjustment unit, Combustion monitoring means for monitoring the combustion state of the burner and for instructing the fuel supply adjusting means when detecting misfire and cutting off the fuel supply to the burner, the blower rotating at a predetermined rotation speed or less. When the combustion monitoring means detects the misfire of the burner during the operation, the combustion control means performs the reignition operation.

(3) With the construction of (1) or (2) above, the combustion air of the burner is taken in from the outside and the combustion exhaust gas is discharged to the outside.

(4) The reignition operation, which has the configuration of (1) or (2) or (3) above, and which detects a misfire of the burner before a set time elapses from the ignition of the burner. Is prohibited.

(5) The above-mentioned re-ignition operation performed by the combustion control means is within a predetermined number of times, which has the configuration of (1) or (2) or (3) or (4) above.

[0010]

[Action]

[Claim 1] The combustion control means instructs the fuel supply adjusting means to supply fuel to the burner, and
The ignition means is instructed to ignite the burner, and the burner is ignited. Then, the combustion control means instructs the fuel supply adjusting means to burn the burner with a predetermined combustion amount. Further, the combustion monitoring means monitors the combustion state of the burner, and when detecting a misfire, instructs the fuel supply adjusting means to cut off the fuel supply to the burner.

When the burner is burning at a predetermined combustion amount or less (determined by an instruction value to the fuel supply adjusting means or the like) at the time of misfire, the combustion control means performs a reignition operation. In the re-ignition operation, as in the initial ignition operation, the fuel supply adjusting means is instructed to supply the fuel to the burner and the ignition means is instructed to ignite the burner.

[Claim 2] The combustion control means starts energization of the blower so that combustion air is supplied to the burner, and instructs the fuel supply control means to supply fuel to the burner, and ignites. Instruct the means to ignite the burner,
Ignite the burner.

The combustion control means controls the number of revolutions of the blower so that the blower is rotated at a number of revolutions to obtain an amount of blown air commensurate with the instructed amount of combustion, so that the burner burns at a predetermined amount of combustion. Instruct the supply control means. Further, the combustion monitoring means monitors the combustion state of the burner, and when detecting a misfire, instructs the fuel supply adjusting means to cut off the fuel supply to the burner.

When the number of revolutions of the blower at the time of detecting the misfire is less than the predetermined value, the combustion control means performs the re-ignition operation.
The re-ignition operation, like the initial ignition operation, starts energizing the blower so that combustion air is supplied to the burner, and instructs the fuel supply adjusting means to supply fuel to the burner. Instruct the burner to ignite.

[Claim 3] The combustion device is configured to take in the combustion air of the burner from the outside and discharge the combustion exhaust to the outside.

[Claim 4] When the combustion monitoring means detects the misfire of the burner before the set time has elapsed from the ignition of the burner, the reignition operation by the combustion control means is prohibited.

[Claim 5] The re-ignition operation performed by the combustion control means is within a predetermined number of times.

[0018]

【The invention's effect】

[Claim 1] When the burner misfires during combustion when the burner is below a predetermined combustion amount, the combustion monitoring means instructs the fuel supply adjusting means to cut off the fuel supply to the burner, but the combustion control means reignites. Burner combustion can be automatically restarted.

When the burner burns in excess of a predetermined combustion amount, it is unlikely to be affected by external disturbance such as wind, and when a misfire occurs, it is highly likely that the combustion device has a cause. The control means does not perform the reignition operation.

[Claim 2] Since the blower is controlled so as to rotate at a rotation speed at which a blower amount commensurate with the combustion amount is obtained, when the blower rotates at a predetermined rotation number or less, a small combustion amount is obtained. Is easily affected by the wind, and the burner may misfire due to the wind.

When the burner misfires, the combustion monitoring means instructs the fuel supply adjusting means and the like to cut off the fuel supply. However, since the combustion control means performs the re-ignition operation, the combustion of the burner can be automatically restarted. You can

When the blower is rotating at a high combustion rate exceeding a predetermined number of revolutions, it is unlikely to be affected by wind or the like, and when a misfire occurs, there is a high possibility that there is a cause on the combustion device side. The control means does not perform the reignition operation.

[Claim 3] In the case of a combustion apparatus that takes in the combustion air of the burner from the outside and discharges the combustion exhaust to the outside, the combustion of the burner is easily affected by wind and the like. Therefore, in the combustion device having such a configuration, it is possible to greatly improve the convenience by performing the re-ignition in consideration of the influence of the wind as described above.

[Claim 4] When the misfire is detected before the set time elapses from the ignition of the burner, the combustion control means prohibits the re-ignition operation. This is because if the burner ignites within the set time after ignition, there is a high possibility that the combustion device side has a cause due to the influence of disturbance such as wind, so prevent the combustion monitoring means from performing re-ignition operation. ing.

[Claim 5] It is specified that the re-ignition operation performed by the combustion control means is within a predetermined number of times.
This is because if a misfire occurs even after the re-ignition operation is performed more than a predetermined number of times, it is highly likely that the cause is on the combustion device side due to the influence of disturbance such as wind.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention (corresponding to claims 1 to 5) will be described with reference to FIGS. As shown in the figure
The FF type gas warm air heater A includes a gas burner 2 to which gas is supplied via solenoid valves 11 and 12 and a gas proportional valve 13, a sparker 3 for ignition, and a combustion fan 4 for sucking outside air.
And a combustion controller 5 for controlling the sparker 3, the combustion fan 4, the solenoid valves 11 and 12, and the gas proportional valve 13, and a combustion monitoring means for monitoring the combustion state. Further, 71 is a warm air passage, 72 is a convection fan arranged in the warm air passage 71, 7
Reference numeral 3 designates a combustion air passage extending from an intake / exhaust duct 74, 75
Is a high limit thermistor that detects abnormal temperature rise.

The gas burner 2 is a flame outlet 2 for discharging an air-fuel mixture.
, 11 formed at the tip end thereof and formed at the base end thereof with an air-fuel mixture suction port 212 for sucking primary air and gas,
Nozzles 221 and 22 are provided in the air-fuel mixture inlet 212 of the passage
The gas pipe 22 facing 1 ... Is provided with the solenoid valves 11 and 12, and the gas proportional valve 13 in this order, and the gas is supplied by the continuous gas pipe g to combust compulsorily.

The sparker 3, which is an ignition means, has a flame outlet 211.
The sparkler drive circuit 31 is arranged facing the
When a high voltage is applied, the gas burner 2 is ignited.

The combustion fan 4 is composed of an impeller 41 pivotally mounted in the combustion air passage 73 upstream of the gas burner 2 and a combustion fan motor 42 (DC motor) for driving the impeller 41. The outdoor air 43 is supplied to the gas burner 2. The combustion fan 4 rotates at the ignition rotation speed during ignition, and at the time of temperature control, a temperature control rotation speed (1300 rpm) that obtains combustion air corresponding to a required combustion amount described later.
Rotate at ~ 3600 rpm).

The gas proportional valve 13 is a valve whose opening degree increases in accordance with the energization amount, and when the energization amount is increased, the gas burner 2
The amount of gas supplied to is increased. When the solenoid valves 11 and 12 are energized, they open and supply gas to the gas burner 2. In the gas proportional valve 13, a proportional valve current of an ignition level is supplied at the time of ignition, and a proportional valve current of a temperature adjustment level corresponding to a temperature adjustment rotation speed of the combustion fan 4 described later is supplied at the time of temperature adjustment.

The combustion monitoring means is incorporated in the flame rod 61 facing the combustion flame and the combustion controller 5, and determines whether or not a misfire has occurred in the gas burner 2 based on the presence or absence of the flame current detected by the flame rod 61. Misfire detection circuit 62 for determining
And a microcomputer 50 described later.

The warm air passage 71 has a heater housing 710.
Is a communication passage with an intake port 712 that opens to the upper rear part of the room to suck in the indoor air 711, and a lower part of the front surface of the heater housing 710 that opens to blow hot air 713 into the room. A filter f for removing dust in the room is detachably arranged at the suction port 712, and a guide plate 715 for changing the blowing direction of the warm air 713 is attached to the blowout port 714.

The convection fan 72 includes an impeller 721 pivotally mounted in the warm air passage 71 near the suction port 712, and an impeller 72.
1 and a convection fan motor 722 (AC motor) that drives the air conditioner 1 to generate an air flow 720 from the inlet 712 to the outlet 714. When controlling the temperature, this convection fan 7
An electric current of a level at which an air volume proportional to the required combustion amount described later is obtained is applied to 2.

The combustion air passage 73 has a dual structure intake / exhaust duct 74 in which the upstream end side and the downstream end side are extended to the outside of the room.
A combustion chamber 731 in which the gas burner 2 is provided, which is a passage communicating with the intake port 741 and the exhaust port 742 (see FIG. 2).
Also, a heat exchange portion 732 that releases the heat of the combustion exhaust gas 730 generated by the combustion into the air flow 720 is formed in the passage. The combustion chamber 731 and the heat exchange section 732 are located inside the warm air passage 71.

The combustion controller 5 includes a proportional valve drive circuit 131 for driving the gas proportional valve 13, an electromagnetic valve drive circuit 110 for closing and opening the solenoid valves 11 and 12, and a convection fan motor 7.
22, a convection fan motor drive circuit 723, a combustion fan motor drive circuit 40 that feedback-controls the combustion fan motor 42, a sparker drive circuit 31 that drives the sparker 3, an operation switch 51, and a room temperature setting device 5
2, and the microcomputer 5 for controlling the above-mentioned drive circuits based on the electric signals sent from the room temperature sensor 53.
Has 0 and.

Next, the control of the gas proportional valve 13, the convection fan 72, and the combustion fan 4 by the combustion controller 5 will be described with reference to FIG.
It will be described together with the flowchart of. Set the target room temperature with the room temperature setting device 52 and operate the operation switch 51 to FF
The operation of the gas warm air heater A is started.

At step s1, the microcomputer 5
A value of 0 instructs the combustion fan motor drive circuit 40 to rotate the combustion fan 4 at the ignition speed. Step s2
Then, the microcomputer 50 instructs the solenoid valve drive circuit 110 to keep the solenoid valves 11 and 12 open.

At step s3, the microcomputer 5
Zero instructs the proportional valve drive circuit 131 so that the gas proportional valve current becomes the ignition level. In step s4, the microcomputer 50 instructs the sparker driving circuit 31 to operate the sparker 3 for a predetermined time.

At step s5, the microcomputer 5
0 is the gas burner 2 based on the output of the misfire detection circuit 62.
Determine the combustion state of. If no misfire is detected (N
(O) proceeds to step s6, where misfire is detected (Y
ES) proceeds to step s9. The ignition operation (steps s1 to s4) or the re-ignition operation (steps s14 to s1)
Immediately after the end of (7) (for several hundred ms), the output of the misfire detection circuit 62 is not stable, and therefore the microcomputer 50 does not discriminate the misfire.

At step s6, the microcomputer 5
0 is determined whether or not 10 seconds or more have elapsed from the end of the (re) ignition operation (step s4 or step s17, and it is considered that the gas burner 2 has ignited at this point), and when it has elapsed (YES) Proceeds to step s7, and if not elapsed (NO), returns to step s5.

At step s7, the microcomputer 5
0 instructs the combustion fan motor drive circuit 40 to rotate the combustion fan 4 at a temperature control rotation speed at which combustion air corresponding to a required combustion amount described later is obtained.

Specifically, the microcomputer 50
Is the target room temperature set by the room temperature setting device 52 and the room temperature sensor 5
Based on the temperature difference from the detected room temperature detected in 3, the required heat quantity Q to be released by the gas burner 2 is calculated every predetermined time,
Based on the calculated required heat quantity Q, the number of revolutions of the combustion fan 4 (in the present embodiment, the range of 1300 rpm to 3600 rpm) is determined every predetermined time, and the number of revolutions of the combustion fan 4 is determined.
The combustion fan 4 is feedback-controlled to rotate. Rotational speed of combustion fan 4 = κ · Q (where κ is a coefficient)

At step s8, the microcomputer 5
0 means that the gas burner 2 releases the required heat quantity Q,
At every predetermined time, the proportional valve current is determined (temperature control level) based on the detected rotation speed, and the proportional valve drive circuit 131 is instructed so that the proportional valve current flows to the gas proportional valve 13, and step s5
Return to.

At step s9, the microcomputer 5
0 instructs the solenoid valve drive circuit 110 to keep the solenoid valves 11 and 12 closed.

At step s10, the microcomputer 50 instructs the proportional valve drive circuit 131 so that the gas proportional valve current becomes zero. Further, the combustion fan motor drive circuit 40 is instructed to stop the combustion fan 4.

In step s11, the microcomputer 50 determines whether or not the number of misfires is less than 11, and if the number of misfires is less than 11 (YES), the step s11.
If it is 11 times or more (NO), the process proceeds to step s18.

At step s12, the microcomputer 50 determines whether or not 90 seconds or more have elapsed from the end of the (re) ignition operation {at the end of step s4 or step s17}, and if so (YES), the step s13
If it has not elapsed (NO), go to step s18.
Proceed to.

At step s13, the microcomputer 50 determines that the rotation speed of the combustion fan 4 at the time of misfire is 210.
It is determined whether or not it is 0 rpm or less, and if it is 2100 rpm or less (YES), the process proceeds to step s14 and 210
If it exceeds 0 rpm (NO), the process proceeds to step s18. The rotation speed of the combustion fan 4 at the time of misfire may be detected between steps s5 and s9.

In step s14, the microcomputer 50 instructs the combustion fan motor drive circuit 40 to rotate the combustion fan 4 at the ignition speed. Step s1
5, the microcomputer 50 controls the solenoid valves 11, 12
The solenoid valve drive circuit 110 is instructed to keep the valve open.

In step s16, the microcomputer 50 instructs the proportional valve drive circuit 131 to set the gas proportional valve current to the ignition level. In step s17, the microcomputer 50 instructs the sparker driving circuit 31 to operate the sparker 3 for a predetermined time, and returns to step s5.

The advantages of this embodiment will be described below. [A] The combustion air passage 73 containing the gas burner 2 has a structure in which the upstream end side and the downstream end side communicate with the intake port 741 and the exhaust port 742 of the intake / exhaust duct 74 extending outside the room. Further, since the combustion fan 4 that takes in the combustion air of the gas burner 2 is controlled to rotate at a rotation speed commensurate with the combustion amount of the gas burner 2, the combustion fan 4 rotates at a low rotation speed (2100 rpm or less). ) When the amount of combustion is small, the gas burner 2 is easily affected by wind, and the gas burner 2 may misfire due to the influence of wind.

However, when the gas burner 2 misfires, the microcomputer 50 instructs the solenoid valve drive circuit 110 and the proportional valve drive circuit 131 to stop energizing the solenoid valves 11, 12 and the gas proportional valve 13 to the gas burner 2. The gas supply is shut off (steps s9 and s10), and if the conditions are satisfied, the microcomputer 50 performs a re-ignition operation (steps s14 to s17) to automatically restart the combustion of the gas burner 2. Therefore, the heating operation is automatically restarted (when the condition is satisfied), so that the room temperature does not drop and the comfort is maintained.

It should be noted that the misfire when the combustion fan 4 is rotating over 2100 rpm and the combustion amount is large is likely to be caused by the combustion device side (it is better not to re-ignite).
It is rational because the re-ignition operation is not performed.

[B] It is specified that the microcomputer 50 performs the re-ignition operation only after 90 seconds or more have elapsed from the ignition detection (when no misfire is detected; NO in step s5). If there is a misfire early (before 90 seconds elapse), it is more likely that the combustion device itself has a cause than the effect of wind (it is better not to re-ignite), and careless re-ignition operation can be prevented. .

[C] The microcomputer 50 performs the reignition operation up to 10 times (returning to the 0th time by reclosing the operation switch). If the misfire occurs even after performing the re-ignition operation more than 10 times, it is highly likely that the cause is on the combustion device side due to the influence of the wind, and the careless re-ignition operation can be prevented.

The present invention includes the following embodiments in addition to the above embodiments. a. Detection that the burner is burning below a predetermined combustion amount is not only detection of the number of revolutions of the blower but detection of proportional valve current,
It may be performed by the indicated value of the combustion speed, the current supplied to the blower, the combustion temperature, or the like.

B. The misfire of the burner may be configured by using a thermocouple (thermocouple), both the frame rod and the thermocouple, etc. in addition to the frame rod.

C. The combustion device may be a water heater, a gas stove, a clothes dryer, or the like. d. Although the FF type gas warm air heater is shown in the above embodiment, only the combustion exhaust gas may be discharged outdoors, or the combustion exhaust gas may be discharged indoors (claims 1, 2 and 3). Claims 4 and 5 which are not quoted.

E. The combustion device according to claim 1 may have either a configuration for taking in the combustion air of the burner with a blower or a configuration for ensuring the air without using the blower.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an FF type gas warm air heater according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a state of the FF type gas warm air heater seen from an upper surface (a), a front surface (b), a lateral surface (c), and a rear surface (d).

FIG. 3 is a block diagram of the FF type gas warm air heater.

FIG. 4 is a flowchart showing the operation of the FF type gas warm air heater.

[Explanation of symbols]

 A FF type gas warm air heater (combustion device) 2 gas burner (burner) 3 sparker (ignition means) 4 combustion fan (blower) 5 combustion controller (combustion control means) 11 solenoid valve (fuel supply regulation means) 12 solenoid valve (Fuel supply adjusting means) 13 Gas proportional valve (fuel supply adjusting means) 50 Microcomputer (combustion monitoring means)

Claims (5)

[Claims] 1. A burner to which fuel is supplied via a fuel supply adjusting means, an ignition means for igniting the burner, an operation of the ignition means, and an adjustment of a supply capacity of the fuel supply adjusting means. And a combustion monitoring means for monitoring the combustion state of the burner and, when detecting a misfire, instructing the fuel supply adjusting means to cut off the fuel supply to the burner. A combustion apparatus in which the combustion control means performs a re-ignition operation when the combustion monitoring means detects a misfire of the burner during combustion at a quantity or less. 2. A burner to which fuel is supplied through a fuel supply adjusting means, an ignition means for igniting the burner, and a combustion air to the burner, so as to meet a designated combustion amount. A blower that is controlled to rotate at a rotation speed that obtains a different amount of air, and a combustion control means that controls the operation of the ignition means, the rotation speed of the blower, and the supply capacity of the fuel supply adjustment means, And a combustion monitoring means for monitoring the combustion state of the burner and instructing the fuel supply adjusting means to detect the misfire and interrupting the fuel supply to the burner, and the blower is rotating at a predetermined rotation speed or less. A combustion apparatus in which the combustion control means performs a re-ignition operation when the combustion monitoring means detects a misfire of the burner. 3. The combustion air for the burner is taken in from the outside, and the combustion exhaust gas is discharged to the outside.
Combustion device as described. 4. The combustion according to claim 1, 2 or 3, wherein the re-ignition operation is prohibited when a misfire of the burner is detected before a set time has elapsed from the ignition of the burner. apparatus. 5. The combustion apparatus according to claim 1, wherein the re-ignition operation performed by the combustion control means is within a predetermined number of times.