JP3531400B2 - Combustion device fan motor control method and device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fan motor control method and apparatus for controlling the rotation of a blower fan in a combustion apparatus.

[0002]

2. Description of the Related Art For example, a blower fan forcibly sending combustion air to a combustion section (burner) of a combustion apparatus such as a water heater supplies the burner with a burner so that complete combustion can be ensured. The fan motor control device adjusts the rotation speed of the fan motor according to the supplied fuel amount. In such a water heater, air flow in the air flow passage forming the passage for the combustion air is caused by air flowing from the outside or foreign matter such as soot adheres to the air flow passage, thereby causing air resistance in the air flow passage. If the (flow path resistance) increases, an appropriate amount of air blown corresponding to the combustion quantity cannot be obtained. Therefore, in this type of water heater, usually, the fan motor according to the flow path resistance is used together with the control by the combustion quantity. The number of rotations is being corrected.

That is, in the correction of the rotation speed of the fan motor, there is a certain correlation between the rotation speed of the fan motor, the current flowing to the motor side, and the flow path resistance of the air flow path. Detecting the number of rotations of the motor and the current on the motor side, calculating the flow path resistance from these values,
Based on the calculated flow path resistance, the rotation speed of the fan motor is corrected so that an appropriate air volume can be obtained in the air flow path.

[0004]

However, in the method of detecting the current value on the motor side and controlling the rotation speed of the fan motor from the value as described above, the fan motor rotation speed due to the change of the flow path resistance is used. Since the correction amount is constant, there is a problem that an appropriate combustion state cannot be obtained due to an increase in flow path resistance depending on the ability of the water heater.

That is, at the maximum capacity of this type of combustion device, the exhaust blocking rate (expressed by converting the flow path resistance into the blowing flow path blocking rate), the fan motor speed, and the combustion The relationship with the carbon generation rate is shown in FIG. This Figure 6
Shows the experimental results obtained by the applicant of the present application by actually applying the above control method to a water heater. That is, in the case of the above control method, as is clear from FIG.
Since the rotation speed of the fan motor is also increasing with the increase in the exhaust blocking rate, the amount of carbon dioxide generated is constant up to a certain range and proper combustion is secured, but the exhaust blocking rate remains constant. (In the illustrated example, the blockage rate indicated by the symbol R is about 6
When it rises to 0%), the amount of carbon dioxide contained in the combustion exhaust gas increases sharply thereafter. This means that, in the above-mentioned conventional control method, when the flow path resistance increases and the exhaust blocking rate becomes a certain value or more, the burner becomes an air shortage state,
There is a problem that the combustibility deteriorates and a large amount of carbon dioxide is emitted.

Further, in the case of the conventional control method as described above, since the rotation speed of the fan motor is increased with the increase of the flow path resistance, the flow path resistance becomes excessive, and the rotation speed of the fan motor becomes the motor performance. If the maximum of is reached,
It is said that the motor speed corresponding to the flow path resistance cannot be obtained, and in this case also the burner is in an air-deficient state as in the above case, the burner causes incomplete combustion, and the amount of carbon monoxide contained in the combustion exhaust increases. There was a problem.

Further, in the water heater according to the above-mentioned conventional control method, usually, the rotational speed correction according to the flow passage resistance is started only when the fan motor is in the operating state, so It took some time to reach the proper air flow rate, and there was a problem that the combustibility was poor at the initial stage of burner ignition.

The present invention has been made in view of the above problems, and it is a method of controlling a fan motor of a combustion apparatus capable of obtaining an appropriate combustion state in the entire capacity range without a complicated change in software. And to provide the apparatus.

Another object of the present invention is to maintain good combustibility even when the rotation speed of the fan motor exceeds the motor performance of the fan motor, and to improve combustibility in the initial stage of combustion. To do.

[0010]

In order to achieve the above object, a method of controlling a fan motor of a combustion apparatus according to the present invention is
In the fan motor control method, which controls the fan motor rotation speed of the blower fan according to the combustion amount of the combustion device, and further corrects the controlled rotation speed of the fan motor according to the flow path resistance of the air flow path, It is characterized by performing the following control.

(1) That is, the invention according to claim 1 is
When the number of rotations of the fan motor exceeds a predetermined number of rotations set in advance, correction is performed to make the amount of correction of the number of rotations larger than the amount of correction initially set based on the flow path resistance. That is, in the fan motor control method according to the first aspect of the present invention, the amount of generation of carbon dioxide and the like rapidly increases at a predetermined value of the rotational speed that is set in advance, for example, as the flow path resistance (exhaust gas blocking rate) increases. By setting the rotational speed (rotational speed R in the example of FIG. 6) in advance, the rotational speed of the fan motor can be increased in response to the sudden increase of the carbon dioxide, etc., and is required for proper combustion of the combustion device. The air (oxygen) is always supplied stably.

[0012]

[0013]

(2) Further , in the fan motor control method according to a second aspect of the present invention, during the post-purge operation of the fan motor performed after the operation of the combustion device is stopped, the rotation speed of the fan motor is changed at least twice or more. Determines the flow resistance of the air flow passage at each rotation speed, calculates the flow resistance specific to the environment in which the combustion device is installed, and responds to this specific flow resistance. It is characterized in that the rotation speed correction amount of the fan motor is determined, and the rotation speed correction amount based on the unique flow path resistance is added in advance at the start of the operation of the combustion device to rotate the fan motor. Therefore, according to the second aspect of the present invention, for example, the rotation speed correction amount according to the unique flow path resistance caused by the length and thickness of the exhaust pipe of the combustion device is determined by the fan motor from the beginning of the operation of the combustion device. Since it is added to the rotation of the fan motor, an air flow rate that is close to an appropriate air flow rate can be obtained to some extent from the stage before the fan motor is rotationally controlled based on the actual flow path resistance. Can be expected to improve.

Further, a control device for a fan motor of a combustion device according to the present invention is a device for implementing the method for controlling a fan motor of a combustion device according to claim 1 or 2 , and comprises a combustion part. In a fan motor control device that controls the rotation of a fan motor for blowing air in a combustion device, a voltage detection unit that detects information about a drive voltage on the fan motor side, and a current detection unit that detects information about a drive current on the fan motor side. A current calculation means for correcting and converting the current information detected by the current detection means based on the voltage information detected by the voltage detection means, a rotation speed detection means for detecting the rotation speed of the fan motor, and the current calculation. The flow path resistance of the air flow path blown by the fan motor is determined based on the current information by the means and the rotation speed detected by the rotation speed detection means. Flow rate resistance determining means, an optimum air flow rate determining means for determining an optimum air flow rate based on the combustion amount of the combustion section, an optimum air flow rate determined by the optimum air flow rate determining means, and the flow path resistance determining means An optimum rotation speed judging means for judging the optimum rotation speed of the fan motor based on the flow path resistance judged by the fan motor, and the fan motor based on the optimum rotation speed of the fan motor judged by the optimum rotation speed judging means. In addition to the basic configuration of including a rotation speed control unit that controls the rotation speed of, the following characteristic configuration is provided.

(1) That is, a fan motor control device according to a third aspect of the present invention is a device for carrying out the invention according to the first aspect, wherein the optimum rotation speed determination means is used.
The determined optimum rotation speed exceeds the preset predetermined rotation speed.
The rotation speed determination means for determining whether or not
When the rotational speed exceeds the predetermined rotational speed, the optimum rotating
Characterized in that a rotational speed correcting means for correcting to increase the number.

[0017]

(2) A fan motor control device according to a fourth aspect of the present invention is a device for carrying out the invention according to the second aspect , wherein the fan motor control device is operated after the combustion device is stopped. During the post-purge operation, a rotation speed switching means for instructing the rotation speed control means to switch the rotation speed of the fan motor at least twice or more, and a switching operation by the rotation speed switching means. And an initial correction amount determining means for determining the rotational speed correction amount of the fan motor corresponding to the specific flow channel resistance in the environment in which the combustion device is installed from each of the flow channel resistances.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

Embodiment 1 FIG. 1 is a schematic configuration diagram of a water heater provided with a motor control device of the present invention.
A burner 2 (combustion section) and a heat exchanger 3 are arranged.
A sirocco fan (a fan for blowing) 6 driven by a fan motor 5 is installed inside a fan case 4 continuous to the lower side of the casing 1, and an upper portion of the casing 1 communicates with an exhaust pipe (not shown). The exhaust port 7 is formed.

A fuel supply pipe 8 for supplying a fuel such as gas or oil is connected to the burner 2, and a water supply pipe 10 for supplying water is connected to the heat exchanger 3. . A valve 1 is provided on the fuel supply pipe 8 and the water supply pipe 10.
1 and 12 are interposed, and these valves 11 and 12 are
Is controlled by the hot water supply controller 13.

The motor control device rotates the fan motor 5 in accordance with the supply amount of the fuel supplied to the burner 2 and the flow passage resistance of the air flow passage so that sufficient combustion performance in the burner 2 is ensured. Rectifying and smoothing means 1 for controlling the number
6, power control means 17, rotation speed detection means 18, current detection means 19, voltage detection means 28, duty ratio control means (rotation speed control means) 20, current calculation means 21, optimum air flow rate determination means 22, flow path resistance. Discriminating means 23, optimum rotational speed discriminating means 24, abnormality discriminating means 25 and abnormality processing means 26.
In addition to the main part of the present invention, the present invention further includes a rotation speed correction means 29 for correcting the rotation speed determined by the optimum rotation speed determination means 24.

More specifically, this motor control device rectifies and smoothes AC power from a commercial power supply 15 of, for example, 100 V AC and smoothes it to output DC power.
6, power control means 17 for switching the DC power from the rectifying / smoothing means 16 based on the control pulse to supply it to the fan motor 5 as drive power, and rotation speed detection means 18 for detecting the rotation speed of the fan motor 5. , Rectifying / smoothing means 1
6, a current detecting means 19 for detecting the output current of the motor 6, a voltage detecting means 28 for detecting the output voltage of the rectifying / smoothing means 16, a rotation speed command signal, the rotation speed detected by the rotation speed detecting means 18, and the fan motor 5. Based on the flowing current, the duty ratio control means 20 for controlling the duty ratio of the control pulse so that the rotation speed of the fan motor 5 becomes the command rotation speed, and the output current and voltage detection means detected by the current detection means 19. A current calculation means 21 for calculating the current flowing through the fan motor 5 based on the detected voltage of 28 and the detection information of both the current detection means 19 and the voltage detection means 28.
A fan based on the current calculated by the current calculation unit 21 and the rotation speed detected by the rotation speed detection unit 18; and the optimum air flow rate determination unit 22 that determines the optimum air flow amount based on the combustion amount of the burner 2. The flow path resistance determination means 23 for determining the flow path resistance of the air flow path constituted by the case 4, the casing 1, etc., and the optimum air flow rate determined by the optimum air flow rate determination means 22 and the flow path resistance determination means 23. The optimum rotation speed of the fan motor 5 is determined based on the determined flow path resistance, and the rotation speed command signal is supplied to the duty ratio control means 20 so that the rotation speed of the fan motor 5 becomes the optimum rotation speed. Discriminating means 24 and flow path resistance discriminating means 23
The abnormality determining means 25 for determining the combustion abnormality based on the flow path resistance determined by, and the stop signal is output to the hot water supply control unit 13 when the abnormality determining means 25 determines the combustion abnormality to output the burner 2 Abnormality processing means 26 for stopping combustion
And the above-described rotation speed correction means 29.

The duty ratio control means 20, the current calculation means 21, the optimum air flow rate determination means 22, the flow path resistance determination means 23, the optimum rotation speed determination means 24, the abnormality determination means 25, and the abnormality processing. Means 26 and rotation speed correction means 2
9 is realized by the microcomputer 27. The microcomputer 27 controls the entire combustion device.

FIG. 2 is a circuit block diagram of the drive section of the fan motor 5, and this drive section is mainly the motor drive IC 3
It is composed of 1. This motor drive IC31 is
It is equipped with terminals 31a to 31e, and is equipped with a power control means 17 and a rotation speed detection means 18.

The power control means 17 includes a motor driver 32 for supplying driving power to each coil of the fan motor 5,
A PWM variable speed circuit 33 that switches the drive power supplied to the fan motor 5 by the motor driver 32 is provided. The rotation speed detecting means 18 is the fan motor 5
A rotation logic 35 that calculates the rotation speed of the fan motor 5 based on a detection signal from a Hall IC 34 that includes a plurality of Hall elements built in, and a rotation speed pulse corresponding to the rotation speed calculated by the rotation logic 35 are generated. And a rotation speed pulse generation circuit 36 that operates.

The drive power from the rectifying / smoothing means 16 is input to the terminal 31a, and this drive power is supplied to the power control means 17.
Is supplied to the motor driver 32. The DC power from the auxiliary power supply 37 is input to the terminal 31b, and this DC power is supplied to each part of the motor drive IC 31 as a power supply. A control voltage is input from the duty ratio control means 20 to the terminal 31c, and this control voltage is supplied to the power control means 17
Is supplied to the PWM variable speed circuit 33. From the terminal 31d, a rotation speed pulse is output from the rotation speed pulse generation circuit 36 of the rotation speed detection means 18, and this rotation speed pulse is supplied to the duty ratio control means 20. The terminal 31e is
It is a ground terminal.

The rectifying / smoothing means 16 is realized by, for example, a full-wave rectifier composed of a diode bridge and a smoothing circuit composed of a capacitor, and rectifies and smoothes AC power obtained from a commercial power supply 15 of 100 V, for example. Output power. The power control means 17 is based on the control pulse whose duty ratio is controlled according to the control voltage from the duty ratio control means 20, and based on the control pulse, the rectification smoothing means 1
The DC power from 6 is switched to the fan motor 5
To drive power to.

That is, the DC drive power supplied to the fan motor 5 is PWM-controlled by the power control means 17. The rotation speed detection means 18 is based on a detection signal from a rotation detection sensor composed of a Hall IC 34 including a plurality of Hall elements built in the fan motor 5, based on the detection signal.
The rotation speed pulse of the fan motor 5 is detected, the rotation speed pulse corresponding to the detected rotation speed is supplied to the duty ratio control means 20, and the rotation signal corresponding to the rotation of the rotation element of the fan motor 5 is supplied to the power control means 1.
Supply to 7.

The current detecting means 19 includes a current detecting element 29 such as a resistor or a current transformer, and detects the output current of the rectifying / smoothing means 16. Voltage detecting means 28
Detects the output voltage of the rectifying / smoothing means 16. The duty ratio control means 20 adjusts the control voltage so that the rotation speed of the fan motor 5 becomes the command rotation speed, and supplies the control voltage to the power control means 17.

The fan motor 5 is a three-phase brushless motor, more specifically, a permanent magnet type synchronous motor,
In the present embodiment, it is used to drive the sirocco fan 6 of the combustion device.

FIG. 3 is a circuit block diagram of the power control means 17, which includes a triangular wave transmission circuit 41, a comparator 42, a three-phase distribution circuit 43, and transistors TR1 to TR6. ing. It should be noted that components not directly related to the present invention, such as a diode for protecting the transistors TR1 to TR6 and a circuit for detecting and protecting overcurrent flowing in the coils 5a to 5c of the fan motor 5, are illustrated and described. Is omitted.

The triangular wave oscillation circuit 41 is, for example, 20 KHz.
Outputs a triangular wave with a period of. The comparator 42 is composed of an operational amplifier, and has a triangular wave voltage from the triangular wave transmission circuit 41 and a control voltage V _S from the duty ratio control means 20.
When the control voltage V _S is equal to or higher than the triangular wave voltage, the control voltage V _S is turned on, and when the control voltage V _S is lower than the triangular wave voltage, the control voltage V _S is turned off and a control pulse having a cycle of 20 KHz is output.

That is, the duty ratio of the control pulse changes according to the control voltage V _S from the duty ratio control means 20. The three-phase distribution circuit 43 is responsive to the rotation signal from the rotation speed detection means 18 to form the upper transistor T.
One of R1 to TR3 and the lower transistor T
One of R4 to TR6 is selectively turned on.
For example, when the transistors TR1 and TR5 are on,
A drive current flows from the coil 5a of the fan motor 5 to the coil 5b.

Therefore, the rotation of the fan motor 5 is continued by sequentially switching the coils 5a to 5c for flowing the current and the direction of the current according to the rotational position of the rotor of the fan motor 5. Further, the three-phase distribution circuit 43 turns on / off the transistor to be turned on among the transistors TR4 to TR6 on the lower stage side according to the control pulse from the comparator 42. That is, the three-phase distribution circuit 43
PWM the drive power supplied to the fan motor 5 according to the control voltage V _S from the duty ratio control means 20.
Control.

Here, the operation of the power control means 17 will be briefly summarized. AC power from the commercial power supply 15 is rectified and smoothed by the rectification and smoothing means 16 and is supplied to the fan motor 5 via the power control means 17. It is supplied as driving power. At this time, the drive power supplied to the fan motor 5 is PWM-controlled by the power control means 17 so that the rotation speed of the fan motor 5 is controlled to the command rotation speed.

Now, as shown in FIG. 4, the maximum voltage of the triangular wave from the triangular wave transmission circuit 41 is V _H , the minimum voltage is V _L, and the control voltage from the duty ratio control means 20 is V _S.
Then, as shown in FIG. 5, the control pulse output from the comparator 42 turns on when the control voltage V _S is equal to or higher than the triangular wave voltage, and turns off when the control voltage V _S is lower than the triangular wave voltage. , The pulse train has the same period as the triangular wave.

Since the three-phase distribution circuit 43 applies the control pulse from the comparator 42 to the base of the transistor to be turned on among the transistors TR4 to TR6 on the lower side, the drive power of the fan motor 5 is controlled by the control pulse. Is switched by and the drive power corresponding to the duty ratio of the control pulse is supplied to the fan motor 5.

Next, the rotation speed correction means 29 will be described. The rotation speed correction means 29 is the optimum rotation speed determination means 2 described above.
This is for correcting the rotation speed determined in 4, and in the present embodiment, when the rotation speed commanded by the optimum rotation speed determination means 24 exceeds a preset predetermined rotation speed R, the optimum rotation speed is determined. The number of revolutions calculated by the number discriminating unit 24 is corrected and output to the duty ratio control unit 20. That is, in the rotation speed correction means 29, for example,
When the relationship between the rotation speed of the fan motor 5 to be used, the flow path resistance (exhaust gas blockage rate) and the generated carbon dioxide is as shown in FIG. 6, the rotation speed R set by the rotation speed correction means 29.
Is the point in the figure at which the generation of carbon dioxide sharply increases (that is, 5,400 rpm). And
When the rotation speed determined by the optimum rotation speed determination means 24 exceeds the set rotation speed (5,400 rotations per minute) R, the rotation speed instructed by the optimum rotation speed determination means 24 will be described later. The duty ratio control means 2 is corrected so as to increase according to a program stored in advance.
Output to 0.

Next, the operation of the fan motor control device of the present invention specifically used for a water heater will be described with reference to the flow chart shown in FIG.

When an operation command is input from a remote controller (not shown), the hot water supply control unit 13 causes the valves 11 and 12 to operate.
The ignition operation is started by controlling an igniter (not shown) or the like, and at the same time, a signal corresponding to the combustion amount of the burner 2, that is, the opening amount of the valve 11 is output to the optimum air flow rate determination means 22. As a result, the optimum air flow rate determination unit 22 calculates the optimum air flow rate according to the combustion amount of the burner 2 based on the signal from the hot water supply control unit 13 (step S1 in FIG. 7).

At this time, the fan motor 5 has not yet rotated, and the determination result by the flow path resistance determination means 23 has not been supplied to the optimum air flow rate determination means 22. Therefore, the optimum rotation speed determination means 24 is set in advance. For example 3 per minute
A rotation speed command signal corresponding to an initial rotation speed of about 000 rotations is output to the duty ratio control means 20 (step S2 in FIG. 7). Thereby, the duty ratio control means 20
However, the control voltage V _S that causes the fan motor 5 to rotate at the initial rotation speed is supplied to the power control means 17. As a result, the power control unit 17 controls the drive power by the PWM method, and drives the fan motor 5 so as to rotate at the initial rotation speed.

Next, the abnormality determining means 25 activates the built-in timer (step S3 in FIG. 7).

The current detecting means 19 detects the current flowing through the fan motor 5, and the voltage detecting means 28
The supply voltage is detected by (step S4 in FIG. 7). Further, the rotation speed detecting means 18 is provided in the hall I of the fan motor 5.
Based on the detection signal from C34, the rotation speed of the fan motor 5 is detected (step S5 in FIG. 7).

Next, the current calculating means 21 calculates the current flowing through the fan motor 5 for appropriately obtaining the flow path resistance from the output current of the rectifying / smoothing means 16 detected by the current detecting means 19 (step in FIG. 7). 6).

That is, if there is no voltage fluctuation of the commercial power supply 15 and the output voltage of the rectifying / smoothing means 16 is always constant,
Although it is not necessary to correct the output current of the rectifying / smoothing means 16 detected by the current detecting means 19, in reality, for example, in the case of the commercial power supply 15 of 100 VAC, it varies from 75 to 120 volt. In order to correct the deviation of the change between the output current of the rectifying / smoothing means 16 and the current flowing through the fan motor 5 due to the change, the current calculating means 21 calculates the output current of the rectifying / smoothing means 16 from the output current of the rectifying / smoothing means 16.
It is necessary to calculate the current flowing through the output current and correct the actually detected output current of the rectifying / smoothing means 16. Here, in order to make the description easier to understand, first, the flow path resistance determination operation when it is not necessary to correct the output current of the rectifying / smoothing means 16 will be described.

That is, regarding the relationship between the rotation speed N of the fan motor 5 and the current I flowing through the fan motor 5, as shown in FIG. 8, data on the relationship with the flow path resistance should be held in advance in a memory or the like. Thus, the flow path resistance Φ can be determined from the rotation speed N and the current I. For example, if the current I becomes I ₀ when the rotation speed N is N ₁ or the current I becomes I ₁ when the rotation speed N is N ₂ , it can be determined that the flow path resistance Φ is Φ _1. If the current I becomes I ₀ when the rotation speed N is N ₀ , it can be determined that the flow path resistance Φ is Φ ₀ .

Φ ₀ is smaller than Φ ₁ . Further, the flow path resistance Φ can be experimentally obtained by the following mathematical formula 1, where N is the number of rotations of the fan motor 5 and I is the current flowing through the fan motor 5. However, g (N), f
(N) is a function of the rotation speed N. Alternatively, as another empirical formula, it is obtained by the following mathematical formula 2.

[0049]

[Equation 1]

[0050]

[Equation 2]

Next, the operation of the current calculation means 21 for correcting the current detected by the current detection means 19 will be described. As long as a constant voltage is always supplied from the commercial power source 15, the flow path resistance can be determined by the above method, but in reality, the voltage of the commercial power source 15 varies, and thus it can be determined only by the above method. Instead, correction by the current calculation means 21 becomes necessary.

That is, when the voltage of the commercial power source 15 fluctuates, the relationship between the rotation speed N of the flow path resistance Φ and the current I shown in FIG. 8 fluctuates, for example, as shown in FIG. In this case, a method of previously storing the relational data indicating the flow path resistance shown in FIG. 8 for each voltage value of the commercial power source in consideration of the voltage fluctuation of the commercial power source 15 may be considered. However, in this case, since a very large memory capacity is required, the relational data of the flow path resistance as the reference as shown in FIG. 8 is stored and the current corresponding to the case where the detected current is used as the reference is set as the current. The correction can reduce the memory, and the same effect can be obtained.

Next, the correction performed by the current calculation means 21 will be described in detail. The value of the output voltage of the rectifying / smoothing means 16 detected by the voltage detecting means 28 is V _0, and the value of the output current of the rectifying / smoothing means 16 detected by the current detecting means is I ₀ . Further, the voltage when the data showing the relationship with the flow path resistance held in the memory as shown in FIG. 8 is obtained is the voltage V (in this embodiment, the voltage is AC100V), and when the voltage is V, Let I be the corresponding correction current.

From the standpoint of the amount of work of the fan motor 5, if the electrical / mechanical work conversion efficiency is considered to be 100%, the following formula 3 is established.

[0055]

[Equation 3]

Therefore, the correction current that will flow when the commercial current of AC100V is supplied can be obtained by the following formula 4.

[0057]

[Equation 4]

Thus, in step S6 of FIG.
The current I flowing through the fan motor 5 by the current calculation means 21
Is calculated to correct the output current I ₀ detected by the current calculation means 19, and in step S7 in FIG. 7, the flow path resistance is calculated by the flow path resistance determination means 23 using the corrected current I. The flow path resistance can be accurately obtained regardless of the fluctuation of the commercial power supply 15.

Then, the flow path resistance judging means 23 uses the current and rotation speed detecting means 18 corrected by the current calculating means 21.
The flow path resistance Φ of the blower flow path inside the fan motor 5 and the casing 1 is determined based on the relationship shown in FIG.

Next, the abnormality determining means 25 determines whether the flow path resistance Φ determined by the flow path resistance determining means 23 is between a predetermined lower limit value ΦL and upper limit value ΦH. (Step S8 in FIG. 7). That is, the flow path resistance Φ
Is in a range outside the lower limit value ΦL and the upper limit value ΦH, it is necessary to judge that the flow rate is abnormal because it is not possible to secure an appropriate air flow rate even if the rotation speed of the fan motor 5 is controlled. If the road resistance Φ is between the lower limit value ΦL and the upper limit value ΦH, it is possible to determine a normal state because an appropriate air flow rate can be secured by controlling the rotation speed of the fan motor 5. Note that the first quadrant of FIG. 8 shows the relationship between the current I flowing through the fan motor 5, the rotational speed N, and the flow path resistance Φ, and the fourth quadrant shows the rotational speed N of the fan motor 5, the air flow rate Q, and the flow rate. It represents the relationship with the road resistance Φ.

If the flow path resistance Φ is between the lower limit value ΦL and the upper limit value ΦH, the abnormality determining means 25 determines normal and clears the built-in timer (step S in FIG. 7).
9). As soon as this timer is cleared, it restarts and restarts the timing operation.

Next, in the optimum rotation speed discrimination means 24,
The optimum rotation speed is calculated based on the flow path resistance Φ determined by the flow path resistance determination means 23 and the optimum air flow rate determined by the optimum air flow determination means 22 (step S1 in FIG. 7).
0). That is, the rotation speed N of the fan motor 5 and the air flow rate Q
As shown in FIG. 8, the relationship with the flow path resistance Φ changes. Therefore, in the optimum rotation speed determination means 24, the fan motor 5 is determined based on the combustion amount so as to obtain the optimum air flow rate. The rotation speed is corrected according to the flow path resistance Φ to obtain the optimum rotation speed. It should be noted that, in addition to the determination based on FIG.
_When the reference rotational speed determined based on the reference flow path resistance Φ ₀ and the amount of combustion is Ng, it is determined by, for example, an empirical formula (5) below. Alternatively, as another empirical formula, it can be obtained by the following mathematical formula 6.

[0063]

[Equation 5]

[0064]

[Equation 6]

Next, the optimum rotation speed determined by the optimum rotation speed determination means 24 is used as a rotation speed command signal, and the rotation speed correction means 2 is operated.
9 and the rotation speed correction means 29 performs the following rotation speed correction (step S11 in FIG. 7). That is, as shown in the flowchart of FIG. 10, the rotation speed correction means 29 first determines whether or not the input optimum rotation speed exceeds the predetermined rotation speed R (step S1 in FIG. 10). ). Then, the input rotation speed is the predetermined rotation speed R.
In the following cases, the rotation speed command signal from the optimum rotation speed determination means 24 is directly output to the duty ratio control means 20 without correction (step S2 in FIG. 10). On the other hand, when the optimum rotation speed obtained by the optimum rotation speed determination means 24 exceeds the predetermined rotation speed R, correction is performed to increase the optimum rotation speed (step S3 in FIG. 10). That is, as described above, when the number of rotations of the fan motor 5 exceeds the predetermined number of rotations R, the generation of carbon dioxide in the combustion section 2 rapidly increases, so the number-of-rotations correction unit 29 rapidly increases this carbon dioxide. In order to prevent this, the optimum rotation speed is corrected so as to increase the rotation speed of the fan motor 5. As a method of correcting the rotation speed here, for example, the optimum rotation speed determination means 24 is used.
Assuming that the correction amount of the rotation speed based on the flow path resistance Φ performed in step S2 is X, the rotation speed correction means 29 multiplies the correction amount X by a correction constant a (a is a positive number) to initially set the optimum rotation speed. The correction is made to be larger than the correction amount X of. In other words,
The correction amount aX in the rotation speed correction unit 29 is set to increase as the flow path resistance Φ increases (the exhaust gas blocking rate increases). By correcting the optimum rotation speed of the fan motor 5 in this manner, the shortage of air in the burner 2 is eliminated, and the amount of carbon dioxide emitted from the burner 2 is
For example, as shown in FIG. 11, it is possible to suppress the flow path resistance Φ to a constant level regardless of the increase in the flow path resistance Φ.

Thus, the rotation speed command signal output from the optimum rotation speed determination means 24 and corrected by the rotation speed correction means 29 is output to the duty ratio control means 20 (step S4 in FIG. 10) and the duty ratio control is performed. Means 20
At this time, based on this rotation speed command signal and the actual rotation speed from the rotation speed detecting means 18, a control voltage V _S that makes the fan motor 5 the optimum rotation speed is output to the power control means 17 (Fig. 7 step S12).

As a result, the power control means 17 switches the DC power supplied to the fan motor 5 based on the control voltage from the duty ratio control means 20, and drives the fan motor 5 so as to attain the optimum rotation speed. .

Next, the optimum blown air amount determination means 22 determines whether or not the combustion amount has been changed based on the signal from the hot water supply control unit 13 (step S13 in FIG. 7), and if there is no change, the microcomputer 27. However, it is determined whether or not an operation end instruction has been input from the remote controller (step S14 in FIG. 7), and if not input, the processing returns to step S5. If entered, the routine ends.

Further, in step S13 of FIG. 7, if the optimum air flow rate determination means 22 determines that the combustion amount has changed, the process returns to step S1 of FIG.

Further, in step S8 in FIG. 7, the abnormality determining means 25 causes the flow path resistance Φ to have a predetermined lower limit ΦL.
If it is determined that the time is not between the upper limit ΦH and the upper limit ΦH, the abnormality determining means 25 further determines whether or not the built-in timer is up (step S15 in FIG. 7). 7 Go to step S10. If the time is up, the abnormality processing means 26 is output to the effect that there is an abnormality. That is, since the flow path resistance Φ may constantly change due to the influence of wind or the like, the flow path resistance Φ is determined to be in an abnormal state only when the flow path resistance Φ becomes an abnormal value for a predetermined time or more.

Next, the abnormality processing means 26 inputs a signal indicating the abnormality from the abnormality determining means 25, thereby outputting a stop signal to the hot water supply control portion 13 to stop the combustion of the burner 2 and the like. The abnormality processing is performed (step S16 in FIG. 7), and the routine ends.

As described above, in the present invention, the rectifying / smoothing means 16 for rectifying and smoothing the AC power to output the DC power, and the DC power from the rectifying / smoothing means 16 based on the control pulse to switch the fan motor. 5, a power control means 17 for supplying drive power to the motor 5, a rotation speed detection means 18 for detecting the rotation speed of the fan motor 5, a current detection means 19 for detecting an output current of the rectifying / smoothing means 16, and a rotation speed command signal. When a predetermined voltage is applied on the basis of the output current detected by the current detection means 19 and information on the voltage detected by the voltage detection means 28 based on the rotation speed detected by the rotation speed detection means 18. Since the current calculating means 21 for calculating the current flowing through the fan motor 5 is provided in the above, the electric current flowing through the fan motor 5 regardless of the voltage fluctuation of the commercial power supply 15. Can be known, therefore it becomes possible to properly determine the flow resistance, it is possible to prevent a rapid increase in carbon dioxide emissions due to an increase in flow resistance.

Embodiment 2 Next, another embodiment of the present invention will be described with reference to FIGS. The motor control device shown in FIG. 12 is provided with a combustion amount command means 291 instead of the rotation speed correction means 29 in the first embodiment, and the other basic configuration is the same as in the first embodiment. Therefore, in the following description, the combustion amount command means 291 will be mainly described.

The combustion amount commanding means 291 commands the water heater to decrease the combustion amount when the number of revolutions judged by the optimum number of revolutions judging means 24 exceeds a predetermined predetermined number of revolutions R '. For controlling the duty ratio control means 2
It is realized by the microcomputer 27 together with 0, the current calculation means 21, and the like. More specifically, in the case where the combustion amount commanding means 291 makes the rotation speed of the fan motor 5 correspond to the flow path resistance, the flow path resistance becomes excessive and the rotation speed of the fan motor 5 cannot correspond to this. In other words, when the performance limit of the fan motor 5 is reached, the combustion amount of the combustion device is reduced to drop the rotation speed of the fan motor 5 within a predetermined rotation speed (appropriate rotation range) R ′. The control shown in the flowchart of FIG. 13 is performed based on the rotation speed command signal from the rotation speed determination means 24.

That is, when the rotation speed command signal is input, it is determined whether the rotation speed instructed here is the maximum rotation speed (predetermined rotation speed) R'of the fan motor 5 used. (FIG. 13 step S1). When it is determined that the rotation speed command signal exceeds the predetermined rotation speed R ', an input down command is output to the hot water supply control unit 13 (step S2 in FIG. 13). When the hot water supply control unit 13 receives this input down command, the valve 11 of the fuel supply pipe 8 is narrowed to reduce the fuel supplied to the burner 2 and the combustion amount in the burner 2 is reduced to continue combustion. (FIG. 13 step S3). In this way, when the fan motor 5 reaches the maximum rotational speed R'in the specification, the combustion amount in the burner 2 is reduced, so that the air flow rate determined by the optimum air flow rate determination means 27 decreases. Since the optimum rotation speed in the optimum rotation speed discriminating means 24 is also reduced accordingly, the rotation speed of the fan motor 5 is set within an appropriate range by appropriately setting the ratio of reducing the combustion amount commanded by the input down. The burner 2 can be dropped, and the generation of carbon monoxide or the like in the burner 2 can be suppressed. If it is determined in step S1 in FIG. 13 that the optimum rotation speed is less than the predetermined rotation speed R ', the combustion amount command means 2
At 91, the above determination operation is repeated again, and the rotation speed of the fan motor 5 is always kept in the monitoring state.

FIG. 14 is a flow chart showing the control operation of the combustion amount command means 291 in the modification of the motor control device according to the second embodiment. That is, in the case of this modification, the CO sensor 29 shown by the alternate long and short dash line in FIG.
4 is provided in the air flow passage, and the amount of carbon monoxide detected by the CO sensor 294 is input to the combustion amount command means 291. Then, the combustion amount command means 291 first determines whether or not it is the maximum rotation speed R'in the specification of the fan motor 5 based on the rotation speed command signal (step S1 in FIG. 14). If the maximum speed is exceeded, CO
It is determined whether the amount of carbon monoxide or the like detected by the sensor 294 is within a preset allowable range Y (step S2 in FIG. 14). When it is determined that the value detected by the CO sensor 294 exceeds the allowable range Y, an input down command is issued to the hot water supply control unit 13 (step S3 in FIG. 14), and the combustion amount according to the input down command. Is reduced (step S4 in FIG. 14). In other words, in the case of this modified example, not only the rotation speed of the fan motor 5 is simply monitored, but also the actual carbon monoxide generation amount is detected and the input down command is issued. This can be performed more efficiently and surely than in the case of the second embodiment. In either case of steps S1 and S2 of FIG. 14, when it is determined that the rotation speed is within the predetermined rotation speed R ′ and the allowable range Y, the process returns to step S1 to start the rotation speed monitoring. It is similar to the case.

Embodiment 3 Next, a third embodiment of the present invention will be described with reference to FIGS. 15 and 16. The motor control device shown in FIG. 15 is provided with a rotation speed switching means 292 and an initial correction amount determination means 293 instead of the rotation speed correction means 29 in the first embodiment, and other basic configurations are the same as those in the above embodiment. The same as 1. Therefore, in the following description, the rotation speed switching unit 292 and the initial correction amount determination unit 293 will be mainly described.

The rotation speed switching means 292 and the initial correction amount determination means 293 are arranged so that the combustion operation of the water heater is stopped.
At the time of post-purging operation in which the fan motor 5 is continuously operated for a certain period of time for the purpose of so-called post-boiling prevention and improvement of hot water discharge characteristics at the time of restarting, the flow passage resistance of the air flow passage is determined,
From the result of the determination, the flow path resistance (unique) peculiar to the environment in which the water heater is installed is determined, and the rotation speed correction amount of the fan motor 5 based on this unique flow path resistance is calculated when the water heater is started. It is added to the fan motor speed. That is, originally, the flow path resistance peculiar to this kind is determined in step 7 of FIG. 7 when the water heater is operated, but at the beginning of the operation of the water heater, the flow path resistance is not corrected at all. Without doing so, the fan motor 5 is driven at a preset number of revolutions (about 3000 revolutions per minute in the above example) (see step S2 in FIG. 7). Therefore, until the determination of the flow path resistance is started and the number of rotations of the fan motor 5 is corrected, an appropriate air flow rate set in advance cannot be sent to the air flow path. In order to eliminate such a situation, in the present embodiment, the flow path resistance peculiar to the environment in which the water heater is installed in advance during the post-purge operation is calculated, and the rotation speed correction amount based on this flow path resistance is calculated. The fan motor 5 set at the start of the combustion operation of the water heater.
The above-mentioned problems are alleviated by adding to the number of revolutions and operating.

Specifically, the rotation speed switching means 292 and the initial correction amount determination means 293 are both realized by the microcomputer 27 together with the duty ratio control means 20 and the current calculation means 21. More specifically,
The rotation speed switching means 292 changes the rotation speed of the fan motor 5 stepwise at least twice when the fan motor 5 performs the post-purge operation. In this embodiment, the duty ratio control means 20 is used. On the other hand, by outputting the fan motor rotation speed command signal, the rotation speed of the fan motor 5 can be switched in two steps. The number of revolutions that can be switched here is preferably the number of revolutions R that is close to the number of revolutions of the fan motor 5 at the maximum capacity.
_max and the rotational speed R _min close to the minimum capacity,
Of course, the present invention is not limited to this and can be freely set as appropriate.

On the other hand, the initial correction amount determining means 293 determines, for example, the shape, length, and thickness of the exhaust pipe of the water heater from the flow path resistance at each rotation speed when the rotation speed switching means 292 performs the switching operation. In addition to calculating the flow path resistance peculiar to the environment where the water heater is installed from various conditions such as
This calculation result is stored, and when the operation of the water heater is started again, the rotation speed correction amount due to this unique flow path resistance is added to the output of the optimum rotation speed determination means 24 and the duty ratio control means 20 is added. It is what is sent.

Now, the control operation of the fan motor control device configured as described above will be described with reference to the flowchart of FIG. First, a remote controller or the like (not shown) gives an instruction to stop the combustion operation of the water heater, and the combustion operation of the water heater is stopped (step S1 in FIG. 16). The post-purge operation is started following this combustion operation stop,
At this time, for example, the rotation speed switching means 292 first outputs a rotation speed command signal to the duty ratio control means 20 so that the rotation speed of the fan motor 5 becomes R _max (FIG. 16).
Step S2). Then, the flow path resistance in the state of this rotation speed R _max is determined by the flow path resistance determination means 23, and the result is input to the initial correction amount determination means 293, and the rotation speed R is determined in the initial correction amount determination means 293.
_The rotational speed correction amount _Xmax is determined and stored based on the flow path resistance in the _max state (step S in FIG. 16).
3). Then, the rotation speed switching means 292 outputs a rotation speed command signal for setting the rotation speed of the fan motor 5 to R _min (step S4 in FIG. 16). And again this rotational speed R
Based on the flow path resistance in the state of _min , the initial correction amount determination means 293 determines and stores the correction amount X _min of the rotation speed (step S5 in FIG. 16). In this way, in the initial correction amount determination means 293, the rotation speed correction amounts X _max , _Rmax and R _min at the rotation speeds R _max and R _min of the fan motor 5 are determined.
While learning X _min respectively, from these values,
For example, by calculating an intermediate value between the two values, the correction amount X'of the rotational speed at the restart of the combustion operation is determined, and thereafter,
Every time the hot water heater is instructed to perform the combustion operation, the correction amount X ′ is added to the rotation speed preset at the start of the operation, and the rotation speed command signal is output to the duty control means 20.

As described above, according to the present invention, the fan motor control device learns the flow path resistance peculiar to the installation environment of the water heater during the post-purge operation, and based on this learning result, from the initial stage of the combustion operation. Since the rotation speed is corrected, it is possible to suppress deterioration of the combustibility at the beginning of the combustion operation.

The present invention is not limited to the above embodiment, and various design changes are possible. (1) For example, the rotation speed correction unit 29 shown in the first embodiment has a configuration in which the rotation speed command signal from the optimum rotation speed determination unit 24 is detected to correct the rotation speed of the fan motor 5. However, for example, it is also possible to perform control based on the actual rotation speed detected by the rotation speed detection means 18, and the position where the rotation speed is corrected is also corrected by correcting the output of the duty ratio control means 20. It is also possible to configure. That is, in the present invention, it is sufficient if the rotation speed of the fan motor can be corrected to be larger than the initial correction amount when the predetermined rotation speed is detected, and the preset rotation speed R is also the above-mentioned carbon dioxide. It can be set freely as desired, such as setting it slightly lower than the point where the amount increases sharply.

(2) In the second embodiment, the maximum rotation speed in the specifications of the fan motor 5 is set as the preset rotation speed R ', but this may be set slightly before the maximum rotation speed. It can be changed, and the amount of narrowing down of the fuel supply pipe 8 at the time of input down can also be appropriately changed according to the flow path resistance and the like.

(3) Further, in the third embodiment, the number of revolutions that can be switched is not limited to the maximum value and the minimum value described above, and can be changed as appropriate, and the switching stage is not limited to the above two stages. The number of steps can be changed as appropriate, such as 3 steps or 4 steps.

(4) Further, in the above embodiment, the detection position of the current detecting means 19 is arranged at the output position of the rectifying / smoothing means 16, but it is not limited to this position and the electric power control means 17 It may be provided between the motors 5 or may be arranged on the ground side of the motors 5. Further, if possible, it is not necessary to consider the power consumption of the power control means 17, so it is also a desirable detection method to directly detect before and after the motor 5. Further, any other position may be used as long as it can detect the information about the current.

(5) In the above embodiment, the detection position of the voltage detecting means 28 is arranged at the output position of the rectifying / smoothing means 16, but the voltage of the commercial power supply 15 is not limited to this position. You may make it monitor. Any other position may be used as long as it can detect the voltage-related information. However, when the detection position by the current detection unit 19 and the detection position by the voltage output unit 28 are set to different positions, the above formula 2 is not always applied as it is, but a certain relation is established due to the work amount. Therefore, the current can be corrected by the calculation formula or the relation based on the experimental value.

(6) In the above embodiment, in the flowchart shown in FIG. 7, the process returns to step S5 when it is not finished in step S13, but it may be returned to step S4. In this case, the operations of steps S4 to S15 are performed when the power supply 15 fluctuates even when the air flow rate is not changed.

(7) In the above embodiment, the PWM type fan motor control device has been mainly described, but it may be a PAM type fan motor control device or any other type fan motor control device. Of course, it can be applied.

(8) In the PWM system, the drive IC 3
If the current amount such as 1 is also taken into consideration, more accurate calculation can be performed.

(9) Further, in the above embodiment, an example in which the current detected by the current detecting means 19 is corrected and calculated by the current calculating means 21 in the equation 4 is shown, but this is merely an example. is there. It goes without saying that other correction calculations may be used. Actually, the correction calculation method may be different depending on the characteristics of the motor used, the detection position of the current detection means 19, and the detection position of the voltage detection means 28.

(10) Further, as shown in the above embodiment,
It is needless to say that the mathematical formulas 1, 2, 5, and 6 are examples, and the present invention is not limited to these.

[0093]

As described above in detail, claims 1 and 3
According to the invention, it is possible to suppress a sudden increase in the generation of carbon dioxide due to an increase in flow path resistance, and it becomes possible to perform combustion operation that always maintains good combustibility, and the adverse effect of the generation of carbon dioxide on the global environment is adversely affected. Can be kept low.

[0094]

[0095] According to the invention of claim 2 and 4,
During post-purge operation, the rotation speed correction amount is learned from the unique flow path resistance due to the installation environment of the combustion device, and the fan motor rotation speed at the start of combustion operation is corrected based on this learning result. The correction according to the environment in which it is used will be performed from the beginning of the combustion operation, and it is expected that the combustibility at the start of the operation of the combustion device will be improved compared to the conventional case.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a water heater including a fan motor control device according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram of a motor drive unit of the control device.

FIG. 3 is a circuit diagram of a power control means provided in the control device.

FIG. 4 is a waveform diagram of a triangular wave obtained by a triangular wave oscillator circuit included in the control device.

FIG. 5 is a waveform diagram of a drive voltage supplied to a fan motor controlled by the control device.

FIG. 6 is an explanatory diagram showing the relationship between the exhaust gas blocking rate of the air flow passage, the rotation speed, and carbon dioxide.

FIG. 7 is a flowchart illustrating an operation of the fan motor control device according to the embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a relationship among a current flowing through a fan motor controlled by the control device, a rotation speed, and an air flow rate.

FIG. 9 is an explanatory diagram showing the relationship between the current detected by the current detection means of the control device and the rotation speed of the fan motor.

FIG. 10 is a flowchart illustrating an operation of a rotation speed correction unit of the control device.

FIG. 11 is an explanatory diagram showing the relationship between the exhaust gas blocking rate of the air flow passage, the number of revolutions, and carbon dioxide when the control device is used.

FIG. 12 is a schematic configuration diagram of a water heater including a fan motor control device according to another embodiment of the present invention.

FIG. 13 is a flowchart illustrating an operation of a combustion amount commanding means of the control device.

FIG. 14 is a flowchart illustrating a modified example of the operation of the combustion amount commanding means.

FIG. 15 is a schematic configuration diagram of a water heater including a fan motor control device according to a third embodiment of the present invention.

FIG. 16 is a flowchart illustrating operations of a rotation speed switching unit and an initial correction amount determination unit of the control device.

[Explanation of symbols]

1 Casing 2 Burner (Combustion Section) 3 Heat Exchanger 4 Fan Case 5 Fan Motor 6 Sirocco Fan (Blower Fan) 7 Exhaust Port 8 Fuel Supply Pipe 10 Water Supply Pipes 11, 12 Valves 13 Hot Water Supply Control Unit 15 Commercial Power Supply 16 Rectification Smoothing Means 17 Power control means 18 Rotation speed detection means 19 Current detection means 20 Duty ratio control means (rotation speed control means) 21 Current calculation means 22 Optimal air flow rate determination means 23 Flow path resistance determination means 24 Optimal rotation speed determination means 25 Abnormality determination Means 26 Abnormality processing means 27 Microcomputer 28 Voltage detection means 29 Rotation speed correction means 291 Combustion amount command means 292 Rotation speed switching means 293 Initial correction amount determination means

Front Page Continuation (72) Inventor Hiroki Obara 93 Edo-machi, Chuo-ku, Kobe, Hyogo Prefecture Noritsu Co., Ltd. (56) References JP-A-8-266080 (JP, A) JP-A-8-35654 (JP, A) JP-A-9-210348 (JP, A) JP-A-3-54394 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F23N 3/00 F23N 1/02 101

Claims (4)

(57) [Claims] 1. A fan for controlling a fan motor rotation speed of a blower fan according to a combustion amount of a combustion device, and further correcting the controlled rotation speed of the fan motor according to a flow passage resistance of a blow passage. In the motor control method, when the rotation speed of the fan motor exceeds a predetermined rotation speed set in advance, correction is performed to make the correction amount of the rotation speed larger than the correction amount initially set based on the flow path resistance. A method for controlling a fan motor of a combustion device, comprising: 2. A fan for controlling a fan motor rotation speed of a blower fan according to a combustion amount of a combustion device, and further correcting the controlled rotation speed of the fan motor according to a flow passage resistance of a blower flow passage. In the motor control method, during the post-purge operation of the fan motor performed after the operation of the combustion device is stopped, the rotation speed of the fan motor is changed at least twice or more to determine the flow resistance of the air flow passage at each rotation speed. Then, based on these determination results, the flow path resistance peculiar to the environment in which the combustion device is installed is calculated, and the rotation speed correction amount of the fan motor corresponding to this peculiar flow path resistance is determined. The fan motor control of the combustion device is characterized in that the fan motor is rotated by adding the rotation speed correction amount based on the inherent flow path resistance in advance at the start of the operation of the combustion device. Method. 3. A fan motor control device for controlling rotation of a fan motor for blowing air in a combustion device having a combustion section, wherein voltage detection means for detecting information on drive voltage of the fan motor side, and A current detection unit that detects information about a drive current, a current calculation unit that corrects and converts the current information detected by the current detection unit based on the voltage information detected by the voltage detection unit, and detects the rotation speed of the fan motor. Rotation speed detecting means, and flow path resistance determining means for determining the flow path resistance of the air flow path for the fan motor to blow based on the current information from the current calculating means and the rotation speed detected by the rotation speed detecting means. An optimum air flow rate determination means for determining an optimum air flow rate based on the combustion amount of the combustion section, and an optimum air flow rate determination means determined by the optimum air flow rate determination means. The optimum rotation speed determination means for determining the optimum rotation speed of the fan motor based on the air flow rate and the flow path resistance determined by the flow path resistance determination means, and the optimum of the fan motor determined by the optimum rotation speed determination means And a rotation speed control unit that controls the rotation speed of the fan motor based on the rotation speed, and the optimum rotation speed determined by the optimum rotation speed determination unit is
Determine whether or not it exceeds a preset number of revolutions
A fan motor for a combustion apparatus , comprising: a rotation speed determination means for adjusting the rotation speed and a rotation speed correction means for correcting the rotation speed to increase the optimum rotation speed when the rotation speed exceeds the predetermined rotation speed. Control device. 4. A fan motor control device for controlling the rotation of a fan motor for blowing air in a combustion device having a combustion section, wherein voltage detection means for detecting information on a drive voltage on the fan motor side, and A current detection unit that detects information about a drive current, a current calculation unit that corrects and converts the current information detected by the current detection unit based on the voltage information detected by the voltage detection unit, and detects the rotation speed of the fan motor. Rotation speed detecting means, and flow path resistance determining means for determining the flow path resistance of the air flow path for the fan motor to blow based on the current information from the current calculating means and the rotation speed detected by the rotation speed detecting means. And an optimal air flow rate determining means for determining an optimal air flow rate based on the combustion rate of the combustion section, and an optimal air flow rate determined by the optimal air flow rate determining means. An optimum rotation speed determination unit that determines an optimum rotation speed of the fan motor based on the flow path resistance determined by the flow path resistance determination unit, and an optimum rotation speed of the fan motor determined by the optimum rotation speed determination unit Rotation speed control means for controlling the rotation speed of the fan motor based on the above, and at least 2 times the rotation speed control means in the post-purge operation of the fan motor performed after the operation of the combustion device is stopped. In an environment in which a combustion device is arranged from rotation speed switching means for instructing to operate by switching the rotation speed of the fan motor more than once and from respective flow path resistances when switching operation is performed by the rotation speed switching means. Fanmo combustion apparatus characterized by comprising an initial correction amount determining means for determining the rotational speed correction amount of the fan motor corresponding to the specific flow resistance Motor controller.