JPH08270934A - Combustion apparatus - Google Patents

Abstract

PURPOSE: To drive a fan in the target number of rotations which is not corrected, without requiring manipulation, by initializing correction information stored in a storage means on the basis of a result of abnormality elimination detected by an abnormality elimination detecting means. CONSTITUTION: An excess/lack detecting means 29 is provided, which detects excess or lack between a target air flow rate and an actual air flow rate in a state that a fan 6 is driven in the target number of rotations Ns . It is so designed that a means 27 for setting the target number of rotations corrects the target number of rotations Ns to the excess or lack elimination side on the basis of information detected by the excess/lack detecting means 29. Further, a storage means 34 is provided, which stores correction information ΔN for carrying out the correction of the target number of rotations Ns by the target number-of-rotation setting means 27. In this case, an abnormality elimination detecting means 31 is provided, which detects that the abnormality of an air flow path through which air is caused to flow by the fan 6 has been eliminated. Also, an initializing means 35 is provided, which initializes the correction information ΔN stored in the storage means 34 depending upon a result of abnormality elimination detected by the abnormality elimination detecting means 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan for ventilating combustion air to a burner, and a target for setting a target ventilation amount of combustion air as a target rotational speed of the fan based on the amount of fuel supplied to the burner. A rotation speed setting means, a fan control means for driving the fan at the target rotation speed set by the target rotation speed setting means, and an actual ventilation amount and a target in a state where the fan is driven at the target rotation speed. An excess / deficiency detection means for detecting excess / deficiency with the ventilation amount is provided, and the target rotation speed setting means corrects the target rotation speed to the excess / deficiency elimination side based on the detection information of the excess / deficiency detection means. And a storage device for storing correction information for executing the correction of the target rotation speed by the target rotation speed setting means.

[0002]

2. Description of the Related Art The above-mentioned combustion device is disclosed, for example, in Japanese Patent Laid-Open No. 63-2.
Japanese Patent Publication No. 94420 discloses that a target ventilation amount of combustion air based on a fuel supply amount to a burner is set as a target rotation speed of a fan, and based on detection information of excess and deficiency between an actual ventilation amount and a target ventilation amount. The target speed is corrected to the excess / deficiency elimination side, so if the target rotation speed is corrected to the excess / deficiency elimination side during a certain combustion operation, the fan will be driven with the corrected target rotation speed during the next combustion operation as well. , For example, in comparison with the case where the excess and deficiency of the actual ventilation amount and the target ventilation amount are detected every time the combustion operation is performed and the fan drive is controlled so that the excess or deficiency is eliminated, Although there is an advantage that it is possible to obtain the actual ventilation volume with less excess and deficiency at an early stage, the actual ventilation volume may be over or under the target ventilation volume due to an abnormality that has occurred in the ventilation path of the fan, such as a filter. Clogging or constant The air flow rate under certain conditions is different from the specified flow rate, which is often caused by erroneous installation of a filter, damage to the ventilation passage, or forgetting to install the filter. During combustion operation after eliminating such an abnormality. From this, it is necessary to drive the fan at a target rotation speed that has not been corrected. Therefore, in this type of combustion device, a correction for executing the correction of the target rotation speed conventionally stored in the storage means is performed. When a reset switch for initializing the information is installed and the work that eliminates the abnormality that occurred in the ventilation path is performed, the reset switch is manually operated each time, and the target rotation that has not been corrected from the next combustion operation The fan is driven by the number.

[0003]

According to the above-mentioned prior art, if the reset switch is forgotten to be operated after the abnormality in the ventilation passage has been eliminated, the target ventilation volume will be reduced in the next combustion operation. Therefore, the fan is driven at the target rotational speed that has been corrected and the normal combustion operation is hindered.

The present invention has been made in view of the above circumstances, and with the elimination of the abnormality in the ventilation path, the fan can be operated at a target rotational speed that has not been corrected, without requiring any special human operation. The purpose is to be able to drive.

[0005]

A first characteristic configuration of the present invention for achieving the above object is to provide a fan for ventilating the combustion air to the burner, and the combustion air based on the fuel supply amount to the burner. A target rotation speed setting unit that sets a target ventilation amount as a target rotation speed of the fan, a fan control unit that drives the fan at the target rotation speed set by the target rotation speed setting unit, and a target rotation speed. An excess / deficiency detecting means for detecting excess or deficiency of the actual ventilation amount and the target ventilation amount in the state where the fan is driven is provided, and the target rotation speed setting means is based on the detection information of the excess / deficiency detecting means. A combustion device that is configured to correct the target rotation speed to the excess / deficiency elimination side and is provided with storage means for storing correction information for executing the correction of the target rotation speed by the target rotation speed setting means. In addition, based on the abnormality elimination detection means for detecting that the abnormality of the ventilation path ventilated by the fan is eliminated, and the abnormality elimination detection result by the abnormality elimination detection means, stored in the storage means. An initialization means for initializing the correction information is provided.

A second characteristic configuration of the present invention is that, in the first characteristic configuration, the abnormality of the ventilation passage is a ventilation obstacle in the ventilation passage.

A third characteristic constitution of the present invention is that in the second characteristic constitution, the ventilation obstacle is clogging of a filter provided in the ventilation passage.

According to a fourth characteristic configuration of the present invention, in the third characteristic configuration, the abnormality elimination detecting means detects the attachment / detachment operation of the filter with respect to the ventilation passage to detect that the abnormality of the ventilation passage has been eliminated. It is configured to do so.

A fifth characteristic structure of the present invention is the first, second, third or fourth characteristic structure, wherein the excess / deficiency detecting means is:
It is configured to detect the amount of unburned gas in the exhaust gas and detect that the actual ventilation amount is less than the target ventilation amount.

A sixth characteristic configuration of the present invention is the first, second, third or fourth characteristic configuration, wherein the excess / deficiency detecting means is
Detecting excess or deficiency between the actual work of the fan when it is driven at the target speed and the target work of the fan that is preset corresponding to the target speed, and detects the actual air flow and the target air flow. It is configured to detect an excess or deficiency of the quantity.

A seventh characteristic configuration of the present invention is the first, second, third, fourth, fifth or sixth characteristic configuration, in which the target rotational speed is corrected to a target rotational speed exceeding a set rotational speed. When,
An adjustment range changing means for changing the upper limit value of the adjustment range of the fuel supply amount to the decreasing side is provided.

[0012]

The operation of the first characteristic structure is as follows. When the abnormality of the ventilation path is eliminated, the correction information stored in the storage means is initialized.

The operation of the second characteristic structure is as follows. When the ventilation obstacle in the ventilation path is eliminated, the correction information stored in the storage means is initialized.

The operation of the third characteristic configuration is as follows. When the clogging of the filter provided in the ventilation path is eliminated, the correction information stored in the storage means is initialized.

The operation of the fourth characteristic structure is as follows. When the filter is attached to or removed from the ventilation path,
Assuming that the abnormality of the ventilation path has been eliminated, the correction information stored in the storage means is initialized.

The operation of the fifth characteristic configuration is as follows. The amount of unburned gas in the exhaust gas is detected to detect that the actual ventilation amount is less than the target ventilation amount, and the target rotation speed is corrected to the insufficient elimination side based on the detection information of the lack.

The operation of the sixth characteristic structure is as follows. Detecting excess or deficiency between the actual work of the fan when it is driven at the target speed and the target work of the fan that is preset corresponding to the target speed, and detects the actual air flow and the target air flow. The excess or deficiency with respect to the amount is detected, and the target speed is corrected to the excess or deficiency elimination side based on the detection information of the excess or deficiency.

The operation of the seventh characteristic structure is as follows. When the target rotation speed is corrected to the target rotation speed that exceeds the set rotation speed, the upper limit value of the adjustment range of the fuel supply amount is changed to the decreasing side.

[0019]

According to the first characteristic configuration, since the correction information stored in the storage means is initialized as the abnormality of the ventilation path is eliminated, the correction is performed without requiring any special human operation. The fan can be driven at the target speed that is not set.

According to the second characteristic constitution, in addition to the effect of the first characteristic constitution, when the ventilation passage has a ventilation obstacle, the ventilation amount tends to be insufficient as compared with the target ventilation amount, and the target rotation speed is Although it is corrected on the shortage elimination side, that is, on the rotation speed increasing side, when the ventilation obstacle is eliminated, the correction information stored in the storage means is initialized, so the lift of the flame caused by the excessive ventilation amount And can be prevented from disappearing.

According to the third characteristic constitution, in addition to the effect of the second characteristic constitution, the clogging of the filter is more likely to proceed faster as the ventilation amount is larger, and the number of rotations is increased even though the clogging of the filter is eliminated. If the fan is driven at the target speed that has been corrected to the increasing side, the filter may be clogged quickly due to excessive ventilation, but if the filter is cleared, it is stored in the storage means. Since the correction information that has been set is initialized, such a possibility is small.

According to the fourth characteristic configuration, in addition to the effect of the third characteristic configuration, the attachment / detachment operation associated with the replacement or cleaning of the filter is detected, and the correction information stored in the storage means is initialized. For example, the detection structure can be simplified and malfunctions of the abnormality elimination detecting means are small as compared with the case where the clogging state of the filter is determined to detect that the clogging of the filter is eliminated.

According to the fifth characteristic configuration, the first, second, and third
Alternatively, in addition to the effect of the fourth characteristic configuration, the target rotation speed is detected by detecting the unburned gas amount such as carbon monoxide gas in the exhaust gas, which is likely to occur when the actual ventilation amount is less than the target ventilation amount. It is preferable for safety, because the number is corrected to the side to solve the shortage.

According to the sixth characteristic configuration, the first, second, third
Alternatively, in addition to the effect of the fourth characteristic configuration, the actual work amount of the fan in a state where the fan is driven at the target rotation speed in which the actual ventilation amount is easily reflected and the target rotation speed are set in advance. By detecting the excess and deficiency of the fan's target work amount, the excess and deficiency of the actual ventilation amount and the target ventilation amount are detected, and the target rotation speed is corrected to the excess and deficiency elimination side based on the detection information of the excess and deficiency. , Easy to perform normal combustion operation.

According to the seventh characteristic configuration, in addition to the effect of the first, second, third, fourth, fifth or sixth characteristic configuration,
When the excess / deficiency detection unit detects a shortage of the ventilation amount, the target rotation speed is corrected to the shortage elimination side, that is, the rotation speed increasing side, but the target rotation speed exceeds the upper limit rotation speed of the fan. If corrected, it may be difficult to secure the target air flow rate, and normal combustion operation may not be possible due to an increase in unburned gas in the exhaust, but the target rotation speed exceeds the set rotation speed. If corrected to a number, the upper limit value of the adjustment range of the fuel supply amount is changed to the decreasing side, so such a possibility is small.

[0026]

【Example】

[First Embodiment] FIG. 1 schematically shows a water heater in which a casing 1 is provided with a combustion apparatus A according to the present invention and a heat exchanger 2 for heating water which is heated by the combustion apparatus A. The heat exchanger 2 is connected to a water supply passage W1 for supplying water and a hot water supply passage W2 for supplying heated hot water to a hot water tap (not shown), and the water supply passage W1 is connected to the heat exchanger 2. A water amount sensor S1 for detecting the amount of water supplied and a water temperature sensor S2 for detecting the temperature of water entering the heat exchanger 2 are provided, and a hot water temperature sensor S3 for detecting the hot water temperature of the heat exchanger 2 is provided in the hot water supply passage W2. Is provided.

The combustion apparatus A supplies a fuel gas to a cylinder 6 forming a combustion chamber 4, a burner 5 for heating a heat exchanger 2, a burner 5 for supplying combustion air to a burner 5, and a fan 6 for passing combustion air. Is provided with a fuel gas supply path G, etc., and an igniter 5a for ignition and a frame rod 5b for detecting whether or not the burner 5 is ignited are provided near the burner 5, and the fuel gas supply path G is provided with Two on-off valves V1 and V2 for connecting and disconnecting the fuel gas supply and an electromagnetic gas amount adjusting valve V3 for adjusting the fuel gas supply amount are provided.

As shown in FIGS. 2 and 3, the ventilation path for the fan 6 is formed between the removable front plate 8 forming the front side of the casing 1 and the barrel 4. An air passage 9 and an exhaust passage 11 extending from the combustion chamber 3 inside the cylinder body 4 to the exhaust pipe 10 are provided. An air intake 12 of the air supply passage 9 is provided in the front plate 8, and the fan 6 is driven and rotated. The air sucked from the air intake 12 is discharged to the burner 5 as combustion air, and the combustion exhaust gas generated in the combustion chamber 3 is discharged outside from the exhaust pipe 10 above the cylinder body 4.

As shown in FIGS. 4 and 5, the air intake port 12 is fixed to the filter mounting plate 14 by means of a filter mounting plate 14 which is screwed to a soundproof cover 13 fixed to the casing 1, and is detachably fixed to the filter mounting plate 14. Filter 15
And the filter cover 1 which is detachably fixed to the front plate 8.
6 is provided, and a rubber seal packing 18 is sandwiched between the peripheral edge portion of the rectangular hole 17 formed in the front plate 8 and the filter mounting plate 14, and the filter cover 16 and the front plate 8 are connected to each other. The air flowing into the rectangular hole 17 from between
After passing through the filter 15 and the long hole group 19 formed in the filter mounting plate 14 in order, the air is sucked into the casing 1 through the vent hole 20 formed in the peripheral wall of the filter mounting plate 14.

As shown in FIG. 6, the filter 15 has locking claws 21a and 21b provided on the frame 21 thereof inserted into the back side thereof through the long holes 22a and 22b formed in the filter mounting plate 14, and Filter mounting plate 14
The micro switch MS, which is locked and fixed to the back side of the filter mounting plate 14, is pushed by the locking claw 21a when the filter 15 is locked and fixed, and is turned on when the filter 15 is removed. Is attached.

A burner controller BC for executing combustion control of the burner 5 and rotation speed control of the fan 6 based on a control command from the remote control device R is arranged in the air supply passage 9, and the remote control device R is provided in the remote control device R. An operation switch DS for instructing start / stop of the combustion operation, a hot water supply temperature display 23, a hot water supply temperature setting device 24, a maintenance switch 25, etc. are provided.

The burner controller BC ignites the burner 5 by the igniter 5a when the detected value of the water amount sensor S1 exceeds the set value due to the opening operation of the hot water tap, and the supplied amount of water detected by the water amount sensor S1 and Water temperature sensor S2
The fuel gas supply amount IP to the burner 5 is controlled by the gas amount adjusting valve V3 based on the detected value of the hot water temperature sensor S3.
The combustion gas of the burner 5 is controlled by correcting the fuel gas supply amount IP so that the detected value of 1 matches the set hot water supply temperature.

Further, the burner controller BC is a fan 6
The flow rate of the combustion air to the burner 5 due to
The rotation speed of the electric DC motor for driving the fan 6 is controlled so as to be an appropriate amount with respect to the fuel gas supply amount IP to the.

FIG. 7 is a block diagram showing the control structure of the fan rotation speed in the burner controller BC. The command information from the remote controller R and the aforementioned sensors S1, S2, S are shown in FIG.
Fuel gas supply amount I to the burner 5 based on the detection information of No. 3
A calculation unit 26 for calculating P, a target rotation speed setting means for setting a target ventilation amount of combustion air as a target rotation speed N _S of the fan 6 based on the fuel gas supply amount IP to the burner 5 Section 27, a fan control unit 28 as a fan control unit that drives the fan 6 at the target rotation speed N _S set by the target rotation speed setting unit 27, and a state in which the fan 6 is driven at the target rotation speed N _S When the excess / deficiency detection unit 29 as the excess / deficiency detection means for detecting the excess / deficiency of the actual ventilation amount and the target ventilation amount, the target rotation speed N _S is corrected over a range exceeding the set rotation speed N _MAX , the fuel gas is corrected. Supply IP
Adjustment range changing unit 3 as an adjustment range changing means for changing the maximum supply amount IP _MAX , which is the upper limit value of the adjustment range, to the decreasing side.
0, the abnormality of the ventilation passage ventilated by the fan 6, specifically, the ventilation trouble of the air supply passage 9 (the closed state of the ventilation passage) caused by the clogging of the filter 15 attached to the air intake 12 is eliminated. The actual number of revolutions N _x of the abnormality elimination detection unit 31 and the fan 6 as the abnormality elimination detection means for detecting that
Each of the encoders 32 for detecting is provided.

The excess / deficiency detection unit 29 is provided with a CO sensor 33 for detecting the concentration of CO gas (carbon monoxide gas) which is unburned gas in the combustion exhaust gas in the exhaust passage 11, and the C sensor 33 is provided.
Detects the shortage of the air amount based on the detected CO concentration P _CO by O 2 sensor 33, if the detected CO concentration P _CO exceeds the set value, the incomplete combustion is occurring,
It is detected that the actual ventilation volume is smaller than the target ventilation volume.

When the excess / deficiency detection unit 29 detects that the actual ventilation amount is smaller than the target ventilation amount, the target rotation speed setting unit 27 corrects the target rotation speed N _S to increase. Based on the memory 34 as a storage unit configured to store the correction information ΔN for executing the correction of the target rotation speed N _S by the target rotation speed setting unit 27, and the abnormality elimination detection result by the abnormality elimination detecting unit 31. , And a correction initialization unit 35 as initialization means for initializing the correction information ΔN of the target rotation speed N _S stored in the memory 34.

FIG. 8 is a graph showing the correlation between the fuel gas supply amount IP and the target rotational speed N _S of the fan 6. The solid line in the figure shows the initially set correlation C, and this initially set correlation is shown. The point that the target rotation speed N _S with respect to the maximum supply amount IP _MAX shown by the relationship C is increased by a predetermined correction amount and the point that the target rotation speed N _S with respect to the minimum supply amount IP _{MIN is} increased by a predetermined correction amount. The connecting straight line is the corrected correlation (C + 1) on the first increase side, and the corrected correlation (C
Further, the correction amount is gradually corrected to a correction correlation (C + n) of a plurality of stages that increases by the same correction amount as the above correction amount, and the cumulative amount of these correction amounts is stored as the correction information ΔN in the memory 34.
When the number of corrections on the increasing side reaches the set number,
It is determined that there is an abnormality, and abnormality processing is performed.

The adjustment range changing unit 30 of the fuel gas supply amount IP determines the maximum possible rotation speed N _MAX of the fan 6 in the correlation between the fuel gas supply amount IP corrected to the increasing side and the target rotation speed N _S. If there is a portion that exceeds the limit, the maximum supply amount IP _MAX of the fuel gas is changed to the decreasing side, that is, the fuel supply amount IP _C corresponding to the maximum possible rotational speed N _MAX .

The abnormality elimination detector 31 includes the filter 1
The fact that the ventilation failure of the air supply passage 9 due to the clogging of No. 5 is eliminated is indirectly detected by detecting the attachment / detachment operation of the filter 15 with respect to the filter mounting plate 14 accompanying the cleaning or replacement of the filter 15. , Filter 15
When the removal of the clogging of the filter 15 is detected based on the input of the removal detection signal D _T from the micro switch MS which is turned off in accordance with the removal from the filter mounting plate 14, the correction initialization unit. By 35, the correction information ΔN stored in the memory 34 is cleared to zero.

Next, the control flow of the fan rotation speed in the burner controller BC will be described with reference to FIGS. 9 and 10. When the power is turned on, the filter 1 is detected based on the presence or absence of the removal detection signal D _T from the microswitch MS.
5 is removed from the filter mounting plate 14 (step 1), and if the filter 15 is removed, the correction information ΔN stored in the memory 34 is cleared to zero (step 2). .

When there is a combustion start command, the pre-purge starts, the fuel gas starts to be supplied to the burner 5, and the igniter 5a.
Combustion operation such as ignition is started by (Step 3,
4) It is determined whether or not the correction information ΔN is stored in the memory 34 (step 5). If the correction information ΔT is stored, the target rotation speed setting unit 27 determines the correction information ΔN based on the correction information ΔN. Target speed N _S and fuel gas supply amount IP
The fan 6 corresponding to the fuel gas supply amount IP is corrected based on the corrected correlation (step 6).
The target rotational speed N _S is set and the proportional control operation of the fuel gas supply amount IP, the ventilation amount, the water amount, etc. is executed (step 7).

The excess / deficiency detection unit 29 detects the detected CO concentration P
It is judged whether or not _CO exceeds the set value (step 8). If the detected CO concentration P _CO does not exceed the set value, the proportional control operation is continued until the combustion stop command is issued (step 9), When it is determined that the detected CO concentration P _CO exceeds the set value and incomplete combustion occurs, the target rotation speed setting unit 27 corrects the correlation between the target rotation speed N _S and the fuel gas supply amount IP. (Step 10), the adjustment range changing unit 30 adjusts the corrected target speed N _S and the fuel gas supply amount I.
In relation to P, the maximum possible rotational speed N of the fan 6
It is determined whether there is a portion that exceeds the _MAX (Sutteppu 11), the maximum possible number of revolutions N when _{the MAX} there is are part exceeds the maximum supply amount IP _MAX reduction side, i.e., its maximum possible rotation Fuel gas supply amount corresponding to several N _MAX IP _C
Change to (Step 12).

The maximum supply amount IP_MAXIf you change
In case of change, the changed maximum supply IP _MAXIs preset
Minimum required maximum supply IP_HHave you secured
Determine whether or not (Step 13), maximum supply IP_HTo
If not secured, an error is displayed and burner 5
To stop the supply of fuel gas to the
The firing stop operation is performed (step 14).

When the maximum supply amount IP _H is secured and when the maximum supply amount IP _MAX is not changed, the target rotation speed N _S is set based on the corrected correlation until the combustion stop command is issued. Then, the proportional control operation of the fuel gas supply amount IP, the ventilation amount, the water amount, etc. is continued (step 9).

When there is a combustion stop command, it is judged whether or not the correlation between the target speed N _S and the fuel gas supply amount IP has been corrected (step 15), and if corrected, it is stored in the memory 34. The corrected correction information ΔN is rewritten to the correction information ΔN obtained by integrating the new correction amount (step 1
6) The fuel supply to the burner 5 is stopped, the combustion stop operation such as the start of the after purge is performed (step 17), and the process waits until the next combustion start command is issued.

The operation of clearing the correction information ΔN will be described in detail with reference to the control flow shown in FIG. 11. When the correction information ΔN is stored in the memory 34, the removal detection signal D _T is detected. Then, it is judged whether or not the filter 15 is removed from the filter mounting plate 14 (steps 30 and 31). If the filter 15 is not removed, wait until there is a combustion start command (step 32). If it is removed, a buzzer sounds to inform that there is no filter 15 (step 33). When the filter 15 is attached (step 34), the correction information ΔN stored in the memory 34 is cleared to zero. Then (Step 35),
Wait until there is a combustion start command (step 32).

[Second Embodiment] FIG. 12 shows another embodiment of the abnormality elimination detecting section 31, in which a light projector 36 is provided on the filter cover 16 side with the filter 15 interposed therebetween to receive light from the light projector 36. An optical switch 37 for outputting a signal is provided inside the filter mounting plate 14 so that the filter 15 is less likely to be clogged and a signal D _T exceeding a predetermined threshold value is input from the optical switch 37 to the burner controller BC. When it is detected that the ventilation path 9 (ventilation path) is not obstructed, and the signal D _T exceeding the predetermined threshold value is not input to the burner controller BC from the optical switch 37, the eyes of the filter 15 are detected. detects that the jam has occurred, the clogging of the filter 15 is eliminated, the signal D _T exceeds a predetermined threshold is input to the burner controller BC When, is arranged to detect that ventilation failure air supply passage 9 is eliminated. Other configurations are the same as in the first embodiment.

[Third Embodiment] FIG. 13 shows the target rotational speed N _S.
Actual work D of the fan 6 when driven by
The excess and deficiency of _X and the target work amount D _S of the fan 6 which is preset corresponding to the target rotation speed N _S are detected to detect the excess and deficiency of the actual ventilation amount and the target ventilation amount. The burner controller BC is provided with a shortage detection unit 29, and a target power speed setting unit 27 sets a DC power supply 38, a switch unit 39 for turning on / off the flow of the DC power supply 38 to the fan 6, and a fan 6. conduction ratio D _X of the DC power supply 38 for the fan 6 to be driven at the target rotation speed N _S was
(Example of electric power value for driving showing actual work of fan 6)
A fan control unit 28 as a fan control means for controlling the
The fan 6 has a predetermined target rotation speed N at a predetermined reference pressure.
Reference power value for setting a reference duty ratio D _S corresponding to the reference state to drive with _S (an example of a reference power value indicating a target work rate of the fan 6 which is set in advance corresponding to the target rotation speed N _S) A reference flow rate setting unit 40 and the like as setting means are provided.

The calculation of the reference flow rate D _S is performed by the calculation unit 26.
In the after-purge (ventilation operation performed after the combustion of the burner 5 is stopped) when the operating time of the water heater, which has been accumulated in step 3, slightly exceeds the operating time in the product inspection, that is, 5 hours, A target rotation speed N preset corresponding to the maximum gas supply amount IP _MAX
The flow rate D _X when the fan 6 is driven and rotated by _S is set as the reference flow rate D _S.

The excess / deficiency detector 29 compares the actual flow rate D _X and the reference flow rate D _S at the time when the after purge is executed, and the flow rate D _X is the reference flow rate. Rate D
_If it is on the larger side than _S and the deviations thereof exceed the set value, it is detected that the actual air flow rate is larger than the target air flow rate, and the air flow rate D _X is the reference air flow rate. When the flow rate is smaller than the flow rate D _S and the deviations thereof exceed the set value, it is detected that the actual ventilation amount is smaller than the target ventilation amount.

When the excess / deficiency detection unit 29 detects that the actual ventilation amount is larger than the target ventilation amount, the target rotation speed setting unit 27 sets the target rotation speed N _S and the fuel gas supply amount IP. When the correlation is corrected to the target rotation speed N _S decreasing side, and the excess / deficiency detection unit 29 detects that the actual ventilation amount is smaller than the target ventilation amount, the target rotation speed N _S and the fuel gas supply amount I
The correlation value with P is corrected to the target rotation speed N _S increasing side, and the integrated value ΔN of the correction amount, which is the correction information for executing the correction of these target rotation speed N _S , is stored in the memory 34.

FIG. 14 shows the correlation between the target rotational speed N _S and the fuel gas supply amount IP, the solid line in the figure shows the initially set correlation C, and the broken line in the figure shows the initially set correlation. Corrected correlation (C + n or C-n) corrected stepwise based on the comparison between the C flow rate D _X and the reference flow rate D _S
Indicates.

Corrected correlation (C + n or C-n)
Is the target speed N_SFuel gas to compensate for
Maximum supply IP_MAXTarget speed N for_SGiven
Point increased by correction amount and minimum supply amount of fuel gas IP
_MINTarget speed N for_SIs increased by a predetermined correction amount
The straight line connecting these points is the corrected correlation on the increasing side of the first step.
(C + 1) and the target speed N_STo reduce
If the maximum supply IP_{MA X}Target speed N for_SWhere
A point where the fixed correction amount is decreased and the minimum supply amount IP _MINTo
Target rotation speed N_SThe point where is reduced by a predetermined correction amount
The straight line connecting to and the correction correlation (C-
It becomes 1).

Such a comparison of the flow rate D _X and the reference flow rate D _S is performed for each afterpurge, and when it is necessary to correct to the increasing side, the correction correlation of the first stage ( C +
Further, if it is necessary to gradually correct from 1) to a correction correlation (C + n) of a plurality of stages that increases by the same correction amount as the above correction amount and to correct to the decreasing side, the correction correlation of the first stage ( C-1) is further gradually corrected to a correction correlation (C-n) of a plurality of steps that is decreased by the same correction amount as the above correction amount, and the cumulative value ΔN of the correction amounts on the increasing side and the decreasing side is stored in the memory 34. Then, when the difference between the correction number on the increasing side and the correction number on the decreasing side reaches the set number, it is determined to be abnormal and the abnormality processing is performed. Other configurations are similar to those of the first or second embodiment.

[Other Embodiments] 1. The fan that ventilates the combustion air to the burner may be one that ventilates the combustion air to the burner by sucking the exhaust gas. 2. The excess / deficiency detection means that detects excess or deficiency between the actual ventilation volume and the target ventilation volume indirectly detects the excess or deficiency based on the presence or absence of incomplete combustion and the detection result of the unburned gas volume in the exhaust gas. However, the excess or deficiency may be directly detected based on the detection result of the ventilation amount detection sensor. 3. The abnormality elimination detecting means for detecting that the abnormality of the ventilation passage ventilated by the fan has been eliminated is based on the detection that the abnormality of the ventilation passage is the erroneous mounting of the filter and the regular filter is mounted. Detecting that the abnormality has been resolved, or that the abnormality in the ventilation path is damage to the ventilation path constituent member and that the abnormality has been resolved based on the detection that the constituent member has been repaired Things, and also the abnormality of the ventilation path, forgetting to put on the filter,
It may be that the abnormality is eliminated based on the detection that the filter is attached.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a water heater.

FIG. 2 is a front view showing the inside of the water heater.

FIG. 3 is a side view showing the inside of the water heater.

FIG. 4 is an exploded perspective view of essential parts.

FIG. 5 is a cross-sectional view of the main part

FIG. 6 is a sectional view of the main part

FIG. 7 is a block diagram of the controller.

FIG. 8 is a graph showing a correlation between a target rotation speed and a fuel gas supply amount.

FIG. 9 is a flowchart of control operation

FIG. 10 is a flowchart of control operation.

FIG. 11 is a flowchart of control operation.

FIG. 12 is a cross-sectional view of an essential part showing a second embodiment.

FIG. 13 is a block diagram of a controller showing a third embodiment.

FIG. 14 is a graph showing a correlation between a target rotation speed and a fuel gas supply amount in the third embodiment.

[Explanation of symbols]

5 Burner 6 Fan 9 and 11 Ventilation path 15 Filter 27 Target speed setting means 28 Fan control means 29 Excess / shortage detection means 30 Adjustment range changing means 31 Abnormality elimination detection means 34 Storage means 35 Initialization means D _X Actual work amount D _S Target work amount IP Fuel supply amount IP _MAX upper limit value N _S Target rotation speed N _MAX Set rotation speed ΔN Correction information

Claims (7)

[Claims] 1. A fan (6) for ventilating combustion air to a burner (5), and a target ventilation amount of combustion air based on a fuel supply amount (IP) to said burner (5). ) Target rotation speed setting means (27) set as the target rotation speed (N _S ).
When the at the target rotational speed set by the target rotational speed setting means (27) (N _S) and fan control means (28) for driving the fan (6) in the target rotational speed (N _S) An excess / deficiency detection means (29) for detecting excess or deficiency of the actual ventilation amount and the target ventilation amount in the state where the fan (6) is driven is provided, and the target rotation speed setting means (27) the target rotational speed based on the detection information of the missing detecting means (29) (N _S) and is configured to correct the excess or deficiency eliminate side, wherein the target rotational speed according to the target rotational speed setting means (27) (N _S ) Is a combustion device provided with a storage means (34) for storing correction information (ΔN) for executing the correction, and an abnormality of a ventilation path (9, 11) ventilated by the fan (6). The abnormality elimination detecting means (3) for detecting that the
1) and an initialization means (35) for initializing the correction information (ΔN) stored in the storage means (34) based on the detection result of the abnormality resolution by the abnormality resolution detection means (31). Combustion device provided. 2. The combustion apparatus according to claim 1, wherein the abnormality of the ventilation passages (9, 11) is a ventilation obstacle in the ventilation passages (9, 11). 3. The ventilation path is a ventilation path (9, 11).
The filter (15) provided at the bottom is clogged.
Combustion device as described. 4. The abnormality elimination detection means (31) detects the operation of attaching or detaching the filter (15) to or from the ventilation passage (9, 11), and the abnormality of the ventilation passage (9, 11) is eliminated. The combustion apparatus according to claim 3, wherein the combustion apparatus is configured to detect that. 5. The excess / deficiency detection means (29) is configured to detect the amount of unburned gas in the exhaust gas to detect that the actual ventilation amount is less than the target ventilation amount. The combustion device according to claim 1, 2, 3 or 4. 6. The actual work amount (D _X ) of the fan (6) when the excess / deficiency detecting means (29) is driven at the target rotation speed (N _S ), and the target rotation speed (N _S). ) to detect the excess and deficiency of the target work amount (D _S) of the fan (6) which is set in advance corresponding, configured to detect the excess and deficiency of the actual ventilation rate and the target air amount The combustion device according to claim 1, 2, 3 or 4. Wherein said target rotational speed (N _S) is set rotational speed when (N _MAX) is corrected to the target rotational speed exceeding the upper limit of the adjustment range of the fuel supply amount (IP) (IP _{MA X)} 7. The combustion apparatus according to claim 1, 2, 3, 4, 5 or 6, further comprising adjustment range changing means (30) for changing to a decreasing side.