JP2870436B2 - Combustion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus of a forced supply / exhaust type provided with a blower for supplying combustion air.

[0002]

[Background technology and its problems]

FIG. 1 shows a schematic configuration of a combustion device such as a gas water heater of a forced supply / exhaust type. Reference numeral 1 denotes a heat exchanger, and a tapping temperature Th from the heat exchanger 1 is detected by a tapping temperature detector 7 such as a thermistor. A burner 8 such as a gas burner is provided below the heat exchanger 1, and the amount of combustion of the burner 8 is controlled by an energizing current value of a gas proportional valve 10 (hereinafter, referred to as a proportional valve current). Further, the heat exchanger 1 and the combustion device 8 are housed in the can 2, and the combustion device 8 is provided at the bottom of the can 2.
A blower 11 such as a centrifugal fan (vortex blower) for supplying combustion air to the canister 2 is provided, and an exhaust port 13 is opened on the upper surface of the can body 2. Thus, the water passing through the heat exchanger 1 is exchanged with the heat of combustion of the combustion equipment 8 in the heat exchanger 1 and is heated. Further, the combustion device 8 burns by consuming the combustion air supplied from the blower 11, and the burned gas is discharged from the exhaust port 13 on the upper surface of the can 2.

In a general combustion apparatus, when a tapping temperature set value Ts is input from a setter 15 provided on a control panel or the like, the controller 14 controls the tapping temperature detected by the tapping temperature detector 7. Based on the difference (Th-Ts) between Th and the set temperature Ts, the combustion amount G of the combustion appliance 8 is calculated and set, and the combustion appliance 8 is calculated based on the set combustion amount G.
The feedback control of the gas proportional valve 10 is performed so that the gas burns. Thereby, hot water having a temperature equal to the set temperature Ts is discharged from the heat exchanger 1.

[0004] When the combustion amount G of the combustion appliance 8 is set, the control device 14 simultaneously sets the combustion amount G of the combustion appliance 8.
The target air flow rate is determined so that an appropriate air-fuel ratio is obtained according to the set value of. FIG. 2 is a diagram showing the relationship between the combustion amount G and the blowing amount Q, and a straight line S indicates the relationship between the combustion amount G of the burning appliance 8 and the target blowing amount Q of the blower 11. That is, the straight line S indicates the relationship between the combustion amount G for burning the fuel gas at an appropriate air-fuel ratio and the blown air amount Q, and is substantially at the center of the stable combustion range between the boundary lines A and B. It is located in. The upper boundary line a indicates that the combustion device 8 causes a lift phenomenon when burning in the region above this, and the lower boundary line b indicates that the combustion device 8 fails when burning in the region below this. Indicates complete combustion. For example, assuming that the combustion amount set to the combustion device 8 is G _A , the target air flow amount Q _A can be determined based on the straight line S in FIG.
If supplying combustion air to the burner 8 at the target air volume Q _A, it is possible to burn the fuel gas in the proper air-fuel ratio.

FIGS. 3A and 3B are diagrams showing characteristics of a centrifugal fan generally used as the blower 11.
A straight line S1 in FIG. 3A shows a characteristic curve of the fan rotation speed N and the blown air amount Q when there is no disturbance such as a reverse wind pressure (supply / exhaust resistance: R _A ), and a curve S2 in FIG. The characteristic curve of the fan rotation speed N and the fan motor current I when there is no disturbance such as the back wind pressure (supply / exhaust resistance: R _A ) is shown. Therefore, when the target air volume Q _A is determined as described above,
The target fan speed N _A of the blower 11 can be determined based on the characteristic curve S1 in FIG. 3A, and the control device 14 controls the fan motor 12 so that the fan speed N matches the target fan speed N _A. Control. As a result, the combustion state of the combustion device and the operation state of the blower 11 are shown in FIGS.
Is maintained at the point A of (a) (b), the fan motor current I _A flows through the blower 11 (FIG. 3 (b)), the target air volume Q _A equal air volume Q is combustion air by the blower 11 Supplied. At this time, the combustion state A is in a stable combustion range as shown in FIG. 2, and stable combustion is performed at an appropriate air-fuel ratio.

Next, the wind pressure of the reverse wind is applied to the exhaust path, so that the supply / exhaust resistance (pressure loss) increases, and the supply / exhaust resistance becomes R
Consider the situation that has changed from _A to R _B (> R _A). FIG.
The straight line P1 in (a) shows the relationship between the fan rotation speed N and the blown air amount Q when the wind pressure of the reverse wind is applied (supply / exhaust resistance: R _B ), and the curve P2 in FIG. The relationship between the fan rotation speed N and the fan motor current I in the case of adding (supply / exhaust resistance: R _B ) is shown.

The control device 14 obtains the target fan speed N _A from the target air flow rate Q _A based on the characteristic curves S 1 and S 2 when there is no disturbance, and matches the fan speed N with the target fan speed N _A. The blower 11 is controlled as described above. However, when a pressure loss occurs due to the application of the reverse wind pressure from the exhaust port 13, the relationship between the blowing amount Q and the fan rotation speed N is
Actually, the characteristic changes as shown by a straight line P1 in FIG. 3A. Therefore, if the fan motor 12 is controlled to reach the target fan speed N _A determined based on the characteristic curve S1, a desired target the air flow rate Q _a can not be obtained, had occurred the problem.

Now, assuming that a reverse wind pressure is suddenly applied to the exhaust path and the blower 11 changes from the operation state A on the characteristic curves S1 and S2 to the operation state on the straight lines P1 and P2, the air flow rate becomes Q _B And the combustion state moves from the point A to the point B on the straight line P1 and the curve P2, and the fan speed N increases from the target fan speed N _A. Then, since an increase in the fan rotation speed N is detected, the fan rotation speed N
Control device 1 so that is equal to the target fan speed N _A.
4 operates, and the operating state of the blower 11 is N _A
When moved to equal the point C, air volume Q is transient blowing rate Q _B
And further decreases to Q _C.

As described above, in the conventional combustion device of the constant fan speed control system, the fan speed N is controlled to be equal to the target fan speed N _A. As a result, when wind pressure is applied to the exhaust path, contrary to air volume Q is Q _C greatly deviated from the correct target blowing rate Q _a is the control object. As a result, the combustion state enters a region of incomplete combustion as shown at point C in FIG. 2, and there is a problem that the combustion device causes incomplete combustion or abnormal combustion due to insufficient air.

(Second conventional example: fan motor voltage value constant control method) FIGS. 4 (a) and 4 (b) are diagrams for explaining a conventional method of controlling a combustion device by a fan motor voltage value constant control method. 4A shows a characteristic curve between the fan motor voltage V and the blown air amount Q when there is no disturbance such as a reverse wind pressure (supply / exhaust resistance: R _A ).
The straight line P3 in (a) shows the relationship between the fan motor voltage V and the air flow Q when reverse wind pressure is applied (supply / exhaust resistance: R _B ). A curve S4 in FIG. 4B shows a characteristic curve of the fan motor voltage V and the fan motor current I when there is no disturbance such as a back wind pressure (supply / exhaust resistance: R _A ).
The curve P4 in (b) shows the relationship between the fan motor voltage V and the fan motor current I when a reverse wind pressure is applied (supply / exhaust resistance: R _B ). FIG. 2 and FIG.
A point in (b) represents the operating state of the combustion state and the blower 11 in the absence of disturbance such as reverse wind pressure, B point supply and exhaust resistance of the fan motor voltage value constant control scheme when the change in R _B It shows a combustion state and an operation state.

In this combustion apparatus of the fan motor voltage constant control method, the set target air flow rate Q _A
The target value V of the fan motor voltage is obtained from the characteristic curve S3 of FIG.
_A is determined, and the blower 11 is controlled so that the fan motor voltage V becomes equal to the target value _VA .

However, also in this method, since the fan motor voltage V is controlled so as to be equal to the target value _VA , when the characteristic changes to the straight line P3 due to the application of the reverse wind pressure to the exhaust path. would be burned at point B on the line P3, air volume Q is reduced from the target blowing rate Q _a to Q _B.
Therefore, even in the conventional combustion device of the constant fan motor voltage value control system, when the wind pressure is applied to the exhaust path, the combustion state deviates from the stable combustion range due to the decrease in the blown air amount Q (see FIG. 2). (Point B above), and there is a problem that the combustion device is liable to cause incomplete combustion or abnormal combustion due to insufficient air.

In the above description of each conventional example, the case where a reverse wind pressure is applied to the exhaust path has been described. Conversely, when the exhaust path side has a negative pressure, the same phenomenon occurs, and the combustion occurs. There is a problem that the device becomes excessive in air and causes a lift phenomenon.

(Third Prior Art: Constant Control Method of Fan Motor Current Value) In order to solve the above-mentioned problem, in the combustion apparatus disclosed in Japanese Patent Application Laid-Open No. 5-256439, the fan rotation speed N and the fan motor Instead of controlling the voltage V, the fan motor current I is controlled to be constant.

A curve S5 in FIG. 5 shows a characteristic curve of the fan motor current I and the blown air amount Q when there is no disturbance such as a reverse wind pressure (supply / exhaust resistance: R _A ), and a curve P5 when a reverse wind pressure is applied. The relationship between the fan motor current I and the air flow rate Q at (supply / exhaust resistance: R _B ) is shown. 2 and 5, the point A represents the combustion state and the operating state of the blower 11 when there is no disturbance such as a back wind pressure.
_This shows the combustion state and operating state in the fan motor current value constant control system when the state changes to _B. In the combustion apparatus of the fan motor current constant control method, when the target air volume Q _A is determined for the set combustion amount G _A, the target value I _A of the fan motor current based on the characteristic curve S5 in FIG. 5 is set, the blower 11 is controlled so that the fan motor current I becomes equal to the target value I _a.

According to such a fan motor current constant control method, a reverse wind pressure is applied to the exhaust path, and the combustion state changes from point A on the characteristic curve S5 to point B on the curve P5,
Even air blowing amount is reduced to Q _B, a result of the control device 14 controls the fan motor 12 to match the fan motor current I and its target value I _A, the combustion state moves to a point D on the curve P5 , air volume is increased to Q _D again from Q _B. That is, according to the fan motor current stabilization control method, as represented in Figure 2, even when the reverse wind pressure is applied to the exhaust path, air volume Q _C and fan voltage by the fan rotation speed constant control method compared to air volume Q _B by value stabilization control method, it is controlled to the nearest blowing rate Q _D in the proper target blowing rate Q _a. Therefore, according to the fan motor current value constant control method, even if the characteristics of the blower 11 change due to the application of a reverse wind pressure to the exhaust path, the air-fuel ratio can be finally controlled in a favorable range, As shown by point D, combustion can be performed in a stable combustion range.

In such a fan motor current value control method, although the fan motor current I is controlled to be constant as described above, at the moment when the reverse wind pressure is applied, the blower 11 The fan motor current I
Has a considerable change in value, and also changes abruptly (for example, point E3 in FIGS. 2 and 18). Conversely, the exhaust port 13
Not only when a negative pressure is applied, but also when the reverse wind pressure is released or when the negative pressure is eliminated, the fan motor current I shows a sharp change. Similarly, the fan motor current I also undergoes a drastic change due to a change in the set value of the combustion amount or the like. In these cases, the response of the fan motor currently used takes a considerable amount of time to restore the value of the fan motor current, which has changed greatly once, to its original value, during which the air-fuel ratio of the combustion device falls outside the appropriate range. Will remain. As described above, the fan motor current value control method has a problem that air-fuel ratio controllability at the time of transient response is poor. Further, in the case where disturbances such as the back wind pressure fluctuate constantly due to weather change or the like, the fan motor current fluctuates unstable and is very difficult to stabilize.

[0018]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the prior art, and a first object of the present invention is to provide a constant fan speed control system and a fan motor voltage. In a constant value control type combustion apparatus, the air-fuel ratio is promptly corrected to maintain the combustion state in a stable combustion range even if there is a change in the characteristics of the blower due to a reverse wind pressure, a negative pressure, or the like in an exhaust path. A second object of the present invention is to improve the air-fuel ratio controllability at the time of transient response in a combustion device of a fan motor current value constant control type.

[0019]

DISCLOSURE OF THE INVENTION A combustion apparatus according to a first aspect of the present invention includes a gas combustion appliance, a gas proportional valve for controlling the amount of combustion of the gas combustion appliance, and a blower for supplying combustion air for the gas combustion appliance. In the combustion apparatus, the target fan rotation speed of the blower is determined according to the set combustion amount of the gas-burning appliance, and the fan rotation speed is controlled to match the target fan rotation speed. Means for outputting a fan motor current value of the blower; and gas proportional valve control means for controlling an energizing current value of the gas proportional valve in accordance with the fan motor current value output by the fan motor current value output means. It is characterized by:

In the combustion apparatus according to the first aspect of the present invention, when the amount of combustion of the gas-burning device is set, the target fan speed is determined so as to obtain an appropriate air-fuel ratio, and the fan speed is set to the target fan speed. The fan is controlled at a constant fan speed so as to match the number. On the other hand, the energizing current value of the gas proportional valve is not directly determined and set from the combustion amount as in the related art.
The actual fan motor current of the blower is known, and the energizing current value of the gas proportional valve is controlled so that the air-fuel ratio is appropriate for the air flow obtained from the fan motor current. If there is no change in the characteristics of the blower due to disturbances such as reverse wind pressure, the energized current value of the gas proportional valve determined by such a combustion method matches the value directly obtained from the set combustion amount. The combustion can be performed at an optimum air-fuel ratio, similarly to the combustion device of the constant fan speed control system.

When the characteristics of the blower change due to external disturbance such as reverse wind pressure or the like, the blown air amount changes even if the fan speed is controlled to be constant. However, in the method of the present invention, the fan motor current that changes with the change in the air flow is detected, and the energizing current value of the gas proportional valve current is controlled according to the change in the fan motor current. The amount of combustion of the gas burning appliance is adjusted according to the change. As a result,
Even when a disturbance occurs, the difference between the appropriate air flow rate and the actual air flow rate determined from the actual combustion air volume becomes small, and the gas combustion appliance can be stably burned.

In addition, the gas proportional valve is not affected by the back wind pressure and the like, and has a quick control response. Therefore, when the blown air amount changes due to a change in the characteristics of the blower, the combustion amount quickly changes in response to the change. It can be quickly adjusted to obtain an appropriate air-fuel ratio.

Therefore, in the combustion apparatus according to the first aspect of the present invention, the combustion apparatus is burned in a stable state regardless of the presence or absence of disturbance such as a back wind pressure. Thus, incomplete combustion or abnormal combustion of the fuel gas can be prevented.

Further, in order to stably burn at the optimum air-fuel ratio, the current value of the proportional valve current may be controlled so as to be proportional to the value of the fan motor current. No circuit is required, and the configuration of the control device can be simplified.

According to a second aspect of the present invention, there is provided a combustion apparatus comprising: a gas combustion appliance; a gas proportional valve for controlling a combustion amount of the gas combustion appliance; and a blower for supplying combustion air to the gas combustion appliance. A target value of the fan motor voltage of the blower is determined according to the set combustion amount of the gas-burning apparatus, and the combustion device is configured to control the blower so that the fan motor voltage matches the target value. Means for outputting a fan motor current value of the blower; and gas proportional valve control means for controlling an energizing current value of the gas proportional valve in accordance with the fan motor current value output by the fan motor current value output means. It is characterized by.

In the combustion apparatus according to the second aspect, when the amount of combustion of the gas-burning apparatus is set, a target value of the fan motor voltage is determined so as to obtain an appropriate air-fuel ratio, and the fan motor voltage is adjusted to the target value. The blower is controlled to keep the fan motor voltage value constant so as to match the target value. On the other hand, the energizing current value of the gas proportional valve is not directly determined from the combustion amount and set as in the conventional case, but the actual fan motor current of the blower is known,
The energizing current value of the gas proportional valve is controlled so that the air-fuel ratio becomes appropriate for the air volume obtained from the fan motor current. If there is no change in the characteristics of the blower due to disturbances such as reverse wind pressure, the energized current value of the gas proportional valve determined by such a combustion method matches the value directly obtained from the set combustion amount. The combustion can be performed at the optimum air-fuel ratio, similarly to the combustion apparatus of the constant fan motor voltage value control system.

If the characteristics of the blower change due to disturbance such as reverse wind pressure or the like, the blowing amount changes even if the fan motor voltage is controlled to be constant. However, in the method of the present invention, the fan motor current that changes with the change in the air flow is detected, and the energizing current value of the gas proportional valve current is controlled according to the change in the fan motor current. The amount of combustion of the gas burning appliance is adjusted according to the change. As a result, even when a disturbance occurs, the difference between the appropriate air flow rate and the actual air flow rate determined from the actual combustion volume becomes small, and the gas combustion appliance can be stably burned.

Further, the gas proportional valve is not affected by the back wind pressure and the like, and has a quick control response. Therefore, when the blown air amount changes due to a change in the characteristics of the blower, the combustion amount quickly changes in accordance with the change. It can be quickly adjusted to obtain an appropriate air-fuel ratio.

Therefore, in the combustion device according to the second aspect of the present invention, the combustion device is burned in a stable state regardless of the presence or absence of a disturbance such as a back wind pressure. Thus, incomplete combustion or abnormal combustion of the fuel gas can be prevented.

Further, in order to perform stable combustion at an optimum air-fuel ratio, the current value of the proportional valve current may be controlled so as to be proportional to the value of the fan motor current. No circuit is required, and the configuration of the control device can be simplified.

According to a third aspect of the present invention, there is provided a combustion apparatus comprising: a gas combustion appliance; a gas proportional valve for controlling a combustion amount of the gas combustion appliance; and a blower for supplying combustion air to the gas combustion appliance. A target value of the fan motor current of the blower is determined according to the set combustion amount of the gas-burning appliance, and the combustion device controls the blower so that the fan motor current matches the target value. Means for outputting a fan motor current value of the blower; and gas proportional valve control means for controlling an energizing current value of the gas proportional valve in accordance with the fan motor current value output by the fan motor current value output means. It is characterized by.

In the combustion apparatus according to the third aspect, when the amount of combustion of the gas-burning appliance is set, the target value of the fan motor current is determined so that an appropriate air-fuel ratio is obtained, and the fan motor current is set to the target value. The blower is controlled to keep the fan motor current value constant so as to match the target value. On the other hand, the energizing current value of the gas proportional valve is not directly determined from the combustion amount and set as in the conventional case, but the actual fan motor current of the blower is known,
The energizing current value of the gas proportional valve is controlled so that the air-fuel ratio becomes appropriate for the air flow determined by the fan motor current. Regardless of the presence or absence of a disturbance such as a back wind pressure, the combustion state determined by such a combustion method maintains an optimum air-fuel ratio similarly to a conventional combustion device of a constant fan motor rotation speed control method.

Further, when the fan motor current fluctuates from the target value transiently, the current value of the gas proportional valve current is changed accordingly. Is adjusted. As a result, even when the fan motor current fluctuates transiently, it is possible to prevent the difference between the proper air flow rate and the actual air flow rate determined from the actual combustion volume from becoming large, and to stably burn the gas combustion appliance. Can be done.

Further, since the gas proportional valve is not affected by the back wind pressure and has a quick control response, when the fan motor current changes due to a change in the set value of the blower amount, a change in the characteristics of the blower, or the like, the gas proportional valve responds accordingly. As a result, the amount of combustion can be changed by quickly adjusting the current supplied to the gas proportional valve, and the air-fuel ratio can be quickly adjusted to an appropriate air-fuel ratio.

Therefore, in the combustion apparatus according to the third aspect of the present invention, even when the fan motor current of the blower fluctuates transiently, the combustion apparatus can be burned in a stable state, Incomplete combustion or abnormal combustion of the gas can be prevented.

Further, in order to perform stable combustion at an optimum air-fuel ratio, the value of the proportional valve current may be controlled so as to be proportional to the value of the fan motor current. It is not necessary, and the configuration of the control device can be simplified.

Further, in the embodiments of the combustion apparatus according to the first to third aspects, the combustion amount of the gas combustion appliance is calculated and set based on the temperature difference between the tap water temperature and the set temperature.

In each of the above combustion devices, when a disturbance or the like occurs, the value of the fan motor current changes, and the energizing current value of the gas proportional valve changes accordingly, so that the actual combustion amount is set. Therefore, the outlet temperature differs from the set temperature. However, if the amount of combustion of the gas-fired appliance is feedback-controlled based on the temperature difference between the tapping temperature and the set temperature, the control is performed so that the tapping temperature and the set temperature become equal. As a result, the combustion device maintains a stable combustion state. Meanwhile, the combustion device is controlled such that the difference between the tapping temperature and the set temperature becomes small.

[0039]

【Example】

(Embodiment of Constant Fan Speed Control System) An embodiment of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 6 is a schematic configuration diagram showing a combustion device (gas water heater) GB of a forced supply / exhaust type according to the present invention. A heat exchanger 1 for exchanging water with combustion gas for heating is provided in the can body 2, and a water inlet pipe 3 connected to a water supply source such as city water is provided on the water inlet side of the heat exchanger 1. Tapping pipe 4 connected to tapping side and connected to tapping terminal
Is connected. The water inlet pipe 3 has a water inlet temperature detector 5 including a temperature sensor such as a thermistor for detecting the water inlet temperature Tc, and a water inlet amount detector 6 for detecting a water inlet flow rate W.
Is provided. The tapping pipe 4 is provided with a tapping temperature detector 7 composed of a temperature sensor such as a thermistor for detecting tapping temperature Th. Heat exchanger 1 in can 2
A combustion device 8 such as a gas burner for burning the fuel gas is provided below. A gas supply pipe 9 for supplying the combustion device 8 with the fuel gas is provided for controlling the amount of combustion in the combustion device 8. The gas proportional valve 10 is provided.
A blower 11 such as a centrifugal fan for supplying combustion air to the combustion device 8 is provided at the bottom of the can 2.
An exhaust port 13 for discharging exhaust gas after combustion is opened on the upper surface of the can body 2.

Reference numeral 14 denotes a control device. The control device 14 receives respective detection values from the water input amount detector 6, the water input temperature detector 5, and the tap water temperature detector 7. Further, a set value Ts of the hot water temperature can be input from a setting device 15 provided on a control panel or the like. The control device 14 sets the amount of combustion so as to discharge hot water at the set temperature Ts based on the detected values W, Tc, Th and the set value Ts, and the amount of air blows is appropriate for the set amount of combustion. The fan motor 12 of the blower 11 is controlled as described above, and the energizing current value of the gas proportional valve 10 is controlled based on the fan motor current so that the air-fuel ratio in the combustion device 8 becomes an appropriate value. That is, when the terminal for hot water supply such as curan is opened and water flows from the water inlet pipe 3 to the heat exchanger 1, the fuel gas is burned by the burner 8, and the heat of combustion of the fuel gas and the water Exchange heat. At this time, the control unit 14 controls the combustion amount G so that the tapping temperature Th becomes equal to the set temperature Ts.
Further, the control device 14 controls the air volume Q of the blower 11, and the air for combustion is supplied from the blower 11 to the combustion device 8 so as to have an appropriate air volume according to the set combustion volume G. The combustion device 8 burns by consuming the combustion air supplied from the blower 11, and the burned gas is discharged from the exhaust port 13 on the upper surface of the can 2.

FIG. 7 shows a control device 14 of a constant fan speed control system (the control device 14 of this system is denoted by reference numeral 21 hereinafter).
FIG. 3 is a block diagram showing a specific configuration of (shown by). The control device 21 includes a control operation unit 22, a fan motor drive power supply 25, and a proportional valve current control unit 26. Further, the control calculation unit 22 includes a combustion amount calculation unit 23 and a fan rotation speed control calculation unit 24. The proportional valve current control unit 26 includes a proportional valve current calculation unit 27 and a proportional valve current output unit 28.
29 is a maximum proportional valve current regulator, and 30 is a minimum proportional valve current regulator.

The amount of incoming water flow W from the incoming water amount detector 6, the incoming water temperature Tc from the incoming water temperature detector 5, and the outgoing water temperature Th from the outgoing water temperature detector 7 are always input to the combustion amount calculating section 23. , The value of the set temperature Ts is input from the setter 15. Thus, the combustion amount calculation unit 23 obtains a feedforward calculation value of the combustion amount G in the combustion appliance 8 based on the input water flow rate W, the input water temperature Tc, and the set temperature Ts. Further, tapping temperature Th and its set temperature Ts
The feedback calculation value of the combustion amount G is obtained based on the deviation (Th−Ts) from the above. Then, the combustion amount calculation unit 23 sets the appropriate combustion amount G _A for tapping hot water set temperature Ts based on the feedforward calculation value and the feedback calculation value, the combustion quantity to the fan speed control calculation section 24 transmitting the set value G _a.

The fan rotation speed control calculation unit 24 determines an appropriate target fan rotation speed N _A based on the set value G _A of the combustion amount transmitted from the combustion amount calculation unit 23. For example, from the characteristic curve S of FIG. 2 and the characteristic curve S1 of FIG. 3A, a characteristic curve S6 as shown in FIG. 8 showing the relationship between the combustion amount G and the fan speed N for obtaining an appropriate air-fuel ratio. Is obtained (it can also be determined experimentally), so that the fan rotation speed control calculation unit 2
Reference numeral 4 indicates that the target fan speed N _A can be directly obtained from the set combustion amount G _A by the characteristic curve S6. On the other hand, from the fan motor 12 to the fan rotation speed control
, The actual fan rotation speed Nreal detected by a rotation speed detection circuit (not shown) or the like is fed back via the fan motor drive power supply 25. The fan rotation speed control calculation unit 24 outputs a fan rotation speed control signal to the fan motor drive power supply 25 based on the deviation (Nreal-N _A ) between the target fan rotation speed N _A and the actual fan rotation speed Nreal. The fan motor drive power supply 25 applies a drive voltage based on the fan speed control signal to the fan motor 12 to rotate the fan motor 12. As a result, fan motor 1
2 indicates that the fan rotation speed Nreal is the fan rotation speed control calculation unit 2
Feedback control is always performed so as to match the target fan rotation speed N _A obtained in step 4 (fan rotation speed constant control method).

A fan motor current signal indicating the actual fan motor current Ireal flowing to the fan motor 12 is transmitted from the fan motor drive power supply 25 to the proportional valve current calculation section 27. Proportional valve current calculator 27 calculates the proportional valve current i _G (energizing current) in the original feeding exhaust resistance R _A as a reference based on the value of the fan motor current Ireal received. That is, it is assumed that the proportional valve current when burning the combustor 8 with a certain amount of combustion G is i _G (there is a relationship like a curve S7 in the second quadrant (II) in FIG. 11), and the combustion of the same value Assuming that the fan motor current for operating the blower 11 with the air flow rate Q necessary for burning the combustion appliance 8 at the optimum air-fuel ratio with the amount G is Ireal (determined by the characteristic curves S6 and S2). , The proportional valve current calculator 27 determines the value of the corresponding proportional valve current i _G from the received Ireal.
The value of the proportional valve current i _G obtained from the received value Ireal in the proportional valve current calculation unit 27 in this manner is
8 and output from the proportional valve current output section 28 to the gas proportional valve 1
The proportional valve current i _G of the value determined to 0 is supplied.

Next, the control state of the combustion device GB in the case where there is no disturbance such as a back wind pressure and the supply / exhaust resistance is maintained at R _A will be described more specifically with reference to FIGS. 9, 10 (a) and 10 (b). explain. FIG. 9 is an explanatory diagram showing the characteristic curve S of FIG. 2 in a partially enlarged manner, and FIGS. 10A and 10B are diagrams showing the same characteristics of the blower 11 as FIGS. 3A and 3B. Now, assuming that the combustion amount set by the combustion amount calculation unit 23 is G _A , the target air flow becomes Q _A , and the blower 11 is controlled to the target fan rotation speed N _A. At this time, the fan motor drive power supply 25
Fan motor current sent from because it is Ireal = I _A, combustion amount to the gas proportional valve 10 from the proportional valve current control unit 26 is proportional valve current i _G such that G _A is supplied. Therefore, the actual combustion state of the combustion device GB is maintained at the point A on the characteristic curve S, and is maintained in a stable combustion state.

Next, the supply and exhaust resistance disturbances such as reverse wind pressure is generated Consider the case that changes R _B. Assuming that the combustion amount set by the combustion amount calculation unit 23 based on the incoming water temperature Tc, the incoming water flow rate W, the outgoing water temperature Th, and the set temperature Ts is G _A , the target air blowing amount is Q _A , but FIG. Since the characteristic of a) changes to the curve P1, the blower 11 is controlled to the target fan speed N _A, and as a result, the operating state of the blower 11 changes to the point C, and the actual blower amount becomes the target blower amount Q. the Q _C deviates significantly from the _a. However, since the characteristic in FIG. 10B changes to the curve P2, the fan motor current also changes to I _C. Then, the fan motor drive power supply 25 sends the fan motor current Ireal = I
_C is output. The value of the proportional valve current i _G determined corresponding to the fan motor current I real = I _C is shown in FIG.
(B) and starting from the fan motor current I _C becomes combustion quantity G ₁ obtained following the characteristic curve S2, S1, S reversed as indicated by the dashed line in FIG. In this way, the actual combustion amount of the burning appliance 8 is controlled so as to be G ₁ instead of G _A , and the ideal air flow amount which becomes the optimum combustion state F ₁ with respect to the actual combustion amount G ₁ is Q ₁ . However, the blast volume is from being controlled to be Q _C by fan speed control calculation unit 24, the actual combustion state and E ₁ point 9 slightly deviates from F ₁ point on the characteristic curve S Become.

The advantages of the combustion apparatus according to the present invention become clear when the combustion state at the time of such disturbance is compared with the conventional method of controlling the constant fan speed. In the conventional method, the actual combustion amount of the combustion device is G _A , and the target ventilation amount determined from the characteristic curve S is Q _A. However, when the supply and exhaust resistance due to a disturbance is changed to R _B, since the actual combustion state changes from point A to point C, air volume is changed to Q _C, the target air volume Q _A
Is increased to (Q _A -Q _C ). As a result, the combustion device performs incomplete combustion at point C in the incomplete combustion region. In contrast, in the combustion apparatus GB of the present invention, the combustion state due to disturbance changes from point A to point C, when the air blowing amount is changed from Q _A to Q _C, the fan motor current from I _A to I _C The proportional valve current is changed in response to the change to reduce the combustion amount to G _A
Since modifications to G ₁ from the combustion state changes from point C to _point E. Thus, while the air flow rate remains of Q _C,
Ideal blowing rate Q ₁ with respect to the actual combustion quantity G ₁ at this time
Is as small as (Q ₁ -Q _C ). Briefly, the combustion state moves from point C while maintaining the air volume in Q _C to characteristic curve S side (Figure 9). As a result, as shown in FIG. 9 (or FIG. 2), the combustion device GB operates in the stable combustion range with E _1.
In this respect, stable combustion will occur.

[0048] In the combustion apparatus GB of the present invention, when the combustion in the combustion state E ₁ in this manner, tapping temperature Th is lower than the set temperature Ts. However, since the control device 21 (combustion amount calculation unit 23) sets the combustion amount G so as to increase the tapping temperature Th by feedback control, that is, increases the target fan speed, the combustion state remains stable. until changed to point D from _point E, eventually match the tapping temperature Th at the set temperature Ts, so that is combusted in the same good condition as the conventional proportional valve current stabilization control method.

Further, as described below, according to the system of the present invention, the proportional valve current i _G may be controlled so as to be proportional to the value of the fan motor current I. Can be That is, when the air supply / exhaust resistance is constant, the air volume Q of the blower 11 is proportional to the rotation speed of the fan motor 12 (fan rotation speed N).
Discharge pressure p 1 is proportional to the square of the fan rotational speed N, further mechanical shaft power p _m of the fan motor 12 is known to be proportional to the cube of the fan rotation speed N. Accordingly, when the fan speed is set to p _1, pm ₁ respectively discharge pressure and shaft power when the N _1, the fan speed is the discharge pressure and shaft power when the N ₂ and p _2, p _{m @ 2} respectively,
Between these _{Q 2 / Q 1 = N 2} / N 1 ... p 2 / p 1 = (N 2 / N 1) 2 p m2 / p m1 = (N 2 / N 1) 3 ... relationship of . Here, the shaft power _{p m, p m = T ·} ω ( where, T is the rotation torque of the motor, omega is the angular velocity of the motor), and the rotational torque T is proportional to the fan motor current I, the angular velocity omega rotation Since it is proportional to the number N, the rotational torque, the angular velocity and the fan motor current when the fan speed is N ₁ are T ₁ , ω ₁ , and I ₁ , respectively, and the fan speed is N ₂
Rotational torque, each T ₂ angular velocity and the fan motor current, when omega _2, I ₂ at the time _{of, p m2 / p m1 = (} T 2 · ω 2) / (T 1 · ω 1) = (I 2 · N ₂ ) / (I ₁ · N ₁ ). Therefore, from the formula and the formula, I ₂ / I ₁ = (N ₂ / N ₁ ) ² is obtained. Further, using the formula, the relationship of I ₂ / I ₁ = (Q ₂ / Q ₁ ) ² is obtained. Can be That is, if the air supply / exhaust resistance is constant, the fan motor current is proportional to the square of the blown air amount Q, and if the proportionality constant is α, it can be expressed as I = αQ ² . A characteristic curve S5 of (IV) is obtained.

On the other hand, it is well known that the gas amount is proportional to the square root of the gas pressure. For example, when gas is ejected from a nozzle having a circular hole (gas ejection hole), the gas amount J becomes J = 0.011D ² K (H / d) ^1/2 ... Here, D is the diameter of the gas ejection hole, K is the flow coefficient, H is the gas pressure, and d is the specific gravity of the gas. A gas proportional valve used in a combustion device such as a water heater is generally a so-called governor-type pressure proportional control valve.
As also described in -43204 discloses, since it is one that changes the gas pressure H in proportion to the current of the electromagnetic coil, according to the equation, the amount of gas J is the square root of the proportional valve current i _G Change proportionally. Further, since the combustion amount G of the combustion appliance is proportional to the gas amount J, the combustion amount G is proportional to the proportional valve current i.
It will change in proportion to the square root of _G. Therefore, the proportional valve current i _G is proportional to the square of the combustion amount G, and the proportional constant is β
Can be expressed as i _G = βG ² ... And the curve S in the second quadrant (II) in FIG.
It looks like 7.

On the other hand, the condition (characteristic curve S) for stable combustion at the optimum air-fuel ratio is in a proportional relationship as shown in FIG. 2 (or the third quadrant (III) of FIG. 11). If the (slope of the characteristic curve S) is γ, then Q = γG... From the above formulas, formulas, and formulas, i _G = βG ² = β (Q / γ) ² = [β / (α · γ ² )] I is obtained. Therefore, as shown in the first characteristic curve S8 in quadrant (I) of FIG. 11, the proportional valve current i _G according to the equation
Is controlled so as to be proportional to the fan motor current I, the combustion amount G and the blowing amount Q can be controlled according to the characteristic curve S, and it can be seen that stable combustion can be performed at an optimum air-fuel ratio. Moreover, since the proportional valve current i _G is proportional to the fan motor current I, the input is converted to a square root and output as in the case where the air flow is detected by an air flow sensor or the like and the proportional valve current i _G is determined from the air flow. A special arithmetic circuit is not required, and the configuration of the control device 21 can be simplified.

(Embodiment of Fan Motor Voltage Constant Control System) FIGS. 12 to 15 show a combustion apparatus of a fan motor voltage constant control system according to another embodiment of the present invention. FIG. 12 is a block diagram showing a configuration of a control device 14 used in this method (the control device 14 of this method is indicated by reference numeral 31 below). In the control device 31, when the combustion amount G _A is set by the combustion amount calculation unit 23, the fan motor voltage control calculation unit 32 sets the characteristic curve S9 as shown in FIG.
(For example, the characteristic curve S in FIG. 2 and the characteristic curve S in FIG.
And 3. ), The fan motor voltage V _A that provides the optimum air-fuel ratio is determined, and the fan motor voltage control calculation unit 32 determines the target value V of the fan motor voltage.
_The fan motor 12 is controlled so as to match _A (fan motor voltage value constant control method). On the other hand, the proportional valve current calculator 27 determines the proportional valve current i _G according to the value of the fan motor current Ireal output from the fan motor drive power supply 25, and the proportional valve current output unit 28 outputs the value to the gas proportional valve 10. supplying a current i _G of the proportional valve.

In this control device 31, if the fan speed N is read as the fan motor voltage V, the description of the control device 21 in FIG.
The combustion state will be briefly described with reference to FIGS. 14 and 15A and 15B. First, when there is no disturbance such as a reverse wind pressure, the combustion amount G _A is set by the combustion amount calculation unit 23, and the target value V _A of the fan motor voltage is obtained by the fan motor voltage control calculation unit 32. Is controlled to the target value _VA . The fan motor current at this time is Ireal = I
_Since it is _A , the proportional valve current control unit 26 supplies the proportional valve current i _G to the gas proportional valve 10 so that the combustion amount becomes G _A. Therefore, the combustion device GB performs stable combustion at the point A in FIG.

[0054] When disturbance, such as reverse wind pressure occurs, the combustion quantity G _A is set in the combustion quantity calculating section 23, the fan motor 12 but is controlled at the target value V _A of the fan motor voltage , the characteristics are changed to the curve P3, the combustion state is changed to the point B, the actual air volume becomes Q _B deviates from the target air volume Q _a. On the other hand, at point B, the fan motor current Ir
eal = I _B , so that the combustion device 8 actually has the combustion amount G ₂
In burning, since the blast volume is maintained in Q _B, the actual combustion state becomes E ₂ points in FIG. 14. In the conventional system, whereas the actual large air volume Q _B and (B point) difference between the target blowing rate Q _A (A point) and (Q _A -Q _B), in the manner of the present invention, the actual delivery The difference between the air volume Q _B (point E ₂ ) and the ideal air volume Q ₂ (point F ₂ ) with respect to the actual combustion amount G ₂ becomes as small as (Q ₂ −Q _B ). The point E ₂ is a point where the air flow rate is reduced from the point B to the combustion state of the combustion amount G ₂ while maintaining the blowing amount at Q _B ,
Figure 14 (or FIG. 2) with respect to incomplete combustion at the point B is a combustion of the conventional method as shown in, will be stable combustion at _two points E is in the manner of the present invention.

The actual combustion state E ₂ is also subjected to feedback control so that the tapping temperature Th becomes the set temperature Ts. As a result, the combustion state E ₂ is maintained while maintaining a stable combustion state.
_The temperature changes from point _{2 to} point D, and finally the tapping temperature Th matches the set temperature Ts.

Also in this control device 31, since the proportional valve current i _G is controlled so as to be proportional to the fan motor current I, a special arithmetic circuit is not required and the configuration of the control device 31 can be simplified. it can.

In each of the above embodiments, the case where the supply / exhaust resistance is increased due to the application of the reverse wind pressure is described. However, the same operation is performed when the supply / exhaust resistance is reduced due to the application of the negative pressure to the exhaust path. That can be easily ascertained. Further, even when the characteristics of the blower change due to other causes, a stable combustion state can be similarly maintained.

(Embodiment of Fan Motor Current Constant Control System) FIGS. 16 to 18A and 18B show a fan motor current constant control combustion system according to still another embodiment of the present invention. FIG. 16 shows a control device 14 used in this system.
It is a block diagram showing a configuration of a control device 14 of this system (hereinafter, denoted by reference numeral 33). This control device 33
In, the combustion quantity G _A is set for tapping hot water set temperature Ts in the combustion quantity calculating section 23, the fan motor current control calculation unit 34 characteristic curve S1 shown in FIG. 17
0 (for example,. Which can be determined from the characteristic curve S5 Metropolitan characteristic curve S and 5 in FIG. 2) based on, determines a fan motor current I _A to the optimum air-fuel ratio, the fan motor current control calculation section 34 controls the fan motor current I so as to coincide with the target value I _a of the fan motor current (the fan motor current stabilization control method). On the other hand, the proportional valve current calculator 27 determines the proportional valve current i _G according to the value of the fan motor current Ireal output from the fan motor drive power supply 25, and the proportional valve current output unit 28 outputs the value to the gas proportional valve 10. supplying a current i _G of the proportional valve. The operation of the other components of the control device 33 is the same as that of the control device 21.

Next, the operation of the control device 33 will be described with reference to FIG.
This will be described with reference to (a) and (b). The characteristic curve S in FIG. 18A shows the relationship between the combustion amount G and the blowing amount Q for obtaining the optimum air-fuel ratio, and FIG. 18B shows the relationship between the fan motor current I and the blowing amount Q. a diagram, the characteristic curve S5 and curve P5 has also supply and exhaust resistance 5 is the case of R _a and R _B.

First, consider a case where there is no disturbance such as a back wind pressure and the supply / exhaust resistance is _RA . When the combustion amount set in the combustion quantity calculating unit 23 is assumed to be G _A, the target air volume is next to Q _A, fan motor current of the blower 11 is controlled to the target value I _A. Since this time the fan motor current sent from the fan motor driving power supply 25 is Ireal = I _A, combustion amount to the gas proportional valve 10 from the proportional valve current control unit 26 G _A
The proportional valve current i _G is supplied such that Therefore, the combustion state of the combustion device GB is maintained at the point A on the characteristic curve S,
Maintains a stable combustion state.

[0061] Further, there is no disturbance such as reverse wind pressure (air supply and exhaust resistance: R _A) If, the fan motor current of the blower 11 is changed to transiently I _A ', such as when setting the combustion amount G _A changed think of. The combustion amount set by the combustion amount calculation unit 23 is G
_If it is _A , the target air volume will be Q _A ,
As a result of the operation state 1 moving to the point _A 'along the characteristic curve S5, the actual air flow becomes QA'. On the other hand, the fan motor current transmitted from the fan motor drive power supply 25 is Ire
Since al = I _A ′, the proportional valve current i _G is supplied from the proportional valve current controller 26 to the gas proportional valve 10 so that the combustion amount becomes G _3.
Is supplied. Therefore, the combustion state of the combustion device GB becomes the point A 'on the characteristic curve S, and is maintained in a stable combustion state.
Next, by the feedback control of the controller 33, the combustion state moves from the point A 'to the point A.

Next, the supply and exhaust resistance disturbances such as reverse wind pressure is generated Consider the case where changes in R _B. Assuming that the combustion amount set by the combustion amount calculation unit 23 based on the incoming water temperature Tc, the incoming water flow rate W, the outgoing water temperature Th, and the set temperature Ts is G _A , the target air volume of the blower 11 becomes Q _A , and the fan motor While current is controlled such that I _a, the characteristics of the blower 11 is changed to the curve P5, the operation state of the blower 11 is changed to the point D on the curve P5, the actual air volume is Q _D
Becomes On the other hand, since the fan motor current output to the proportional valve current calculator 27 is iReal = I _A, the gas proportional valve 1
At 0, the proportional valve current i _G is supplied so that the combustion amount becomes G _A. Therefore, the combustion device GB burns at the point D in FIG. 18A, similarly to the conventional constant current value control type combustion device. If the disturbance is not considerably large, the combustion device GB burns in the stable combustion range. However, when the characteristics of the blower 11 is changed by the reverse wind pressure or the like, the fan motor current transiently blower 11 is changed to I _A ', in the combustion apparatus of the conventional constant current value control method decreases the air volume is Q ₃ However, since the combustion amount is kept at G _A , the difference (Q _A −Q ₃ ) between the actual air flow amount Q ₃ and the target air flow amount Q _A increases, and the combustion state becomes E in FIG. There was a risk of incomplete combustion at _three points. In contrast, in the combustion apparatus GB of the present invention, the fan motor current I of the blower 11 is changed to transiently I _A 'in characteristic change or the like, air blowing amount is the Q _3, proportional valve current calculator 27 fan motor current output to become I _a '. Therefore, the gas proportional valve 10 has a combustion amount of G
₃ and the difference between the actual air flow rate Q ₃ and the target air flow rate Q _A ′ is reduced to (Q _A ′ −Q ₃ ), and the combustion state is changed to the point E _{4 in} FIG. And a stable combustion state is maintained.

[0063] Having thus lower than tapping temperature Th is the set temperature Ts during the burning in the combustion state E _4, eventually Returning fan motor current is I _A, the combustion state E while maintaining the stable combustion state _From point _{4 to} point D, a desired tapping temperature is finally obtained.

Also in this embodiment, in order to burn at the optimum air-fuel ratio, the proportional valve current i _G may be controlled so as to be proportional to the value of the fan motor current I. Can be simplified (see FIG. 11).

[0065]

In the combustion apparatus according to the first or second aspect of the present invention, even when the characteristics of the blower change, the combustion amount of the gas-fired appliance is quickly adjusted according to the change in the characteristics of the blower. Therefore, the blower can be stably burned at the optimum air-fuel ratio.

Similarly, in the combustion apparatus according to the third aspect of the present invention, even when the fan motor current of the blower fluctuates transiently, the amount of combustion of the gas combustion appliance is adjusted accordingly. Therefore, the blower can be stably burned at the optimum air-fuel ratio.

Accordingly, the occurrence of vibration combustion and soot due to excessive gas supply can be reduced. Further, even in a failure mode after a failure such as a fin clogging of the heat exchanger, the fan motor current decreases with respect to the fan rotation speed of the blower, thereby decreasing the energizing current value of the gas proportional valve. It will be in the failure mode where the amount decreases,
A failure mode that does not increase the generation of CO gas or fin clogging due to abnormal combustion does not occur.

Also, in these combustion devices, the current supplied to the gas proportional valve is controlled in accordance with the output value of the fan motor current of the blower, so that the gas proportional valve is proportional to the fan motor current. The current value of the gas proportional valve can be controlled by a circuit proportional to the fan motor current without providing a special arithmetic circuit, thereby simplifying the configuration of the control device. Can be.

Also, if the combustion amount of the gas-fired appliance is feedback-controlled based on the difference between the tapping temperature and the set temperature, the tapping temperature and the set temperature are controlled so that the tapping temperature and the set temperature become equal. The combustion device can be controlled so that the difference between the temperature of the hot water and the temperature of the hot water can be controlled so that the tapping temperature can be made close to the set temperature while maintaining a stable combustion state even when there is disturbance or a change in the combustion state.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a forced supply / exhaust type combustion device according to a conventional example.

FIG. 2 is a diagram illustrating a combustion state of a combustion device in a relationship between a combustion amount of a combustion appliance and a blown amount of a blower.

3A and 3B are diagrams for explaining an operation of a conventional fan rotation speed constant control method, in which FIG. 3A shows a relationship between a fan rotation speed and a blowing amount in a blower, and FIG. This shows the relationship with the motor current.

4A and 4B are diagrams for explaining the operation of a conventional fan motor voltage value constant control method, in which FIG. 4A shows a relationship between a fan motor voltage and a blown air amount in a blower, and FIG. This shows the relationship with the motor current.

FIG. 5 is a diagram for explaining the operation of a conventional fan motor current value constant control method based on the relationship between the fan motor current of a blower and the amount of air blow;

FIG. 6 is a schematic configuration diagram showing a combustion device according to an embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a control device of a fan speed constant control system according to the first embodiment;

FIG. 8 is a diagram illustrating an example of a relationship between a combustion amount of a combustion appliance and a fan rotation speed used in a fan rotation speed control calculation unit.

FIG. 9 is a view for explaining the operation principle of the control device of the above.

FIGS. 10A and 10B are diagrams for explaining the operation principle of the control device of the above.

FIG. 11 is a diagram showing a relationship among a fan motor current, a proportional valve current, a combustion amount, and a blown amount.

FIG. 12 is a block diagram showing a configuration of a control device of a fan motor voltage value constant control system according to another embodiment of the present invention.

FIG. 13 is used in a fan motor voltage control calculation unit.
It is a figure showing an example of the relation between the amount of combustion of a burner, and fan motor voltage.

FIG. 14 is a diagram for explaining the operation principle of the control device of the above.

FIGS. 15A and 15B are diagrams for explaining the operation principle of the control device of the above.

FIG. 16 is a block diagram showing a configuration of a control device of a fan motor current value constant control system according to still another embodiment of the present invention.

FIG. 17 is used in a fan motor current control calculation unit.
It is a figure showing an example of the relation between the amount of combustion of a burner, and fan motor current.

FIGS. 18 (a) and (b) are diagrams for explaining the operation principle of the control device of the above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat exchanger 7 Hot water temperature detector 8 Combustion equipment 10 Gas proportional valve 11 Blower 12 Fan motor 14 (21, 31, 33) Control device 15 Setting device 23 Burning amount calculation unit 24 Fan rotation speed control calculation unit 25 Fan motor drive Power supply 27 Proportional valve current calculator 32 Fan motor voltage control calculator 34 Fan motor current control calculator

Claims (4)

(57) [Claims] A gas combustion appliance, a gas proportional valve for controlling a combustion amount of the gas combustion appliance, and a blower for supplying air for combustion of the gas combustion appliance, wherein a set combustion amount of the gas combustion appliance is provided. A combustion fan configured to determine a target fan rotation speed of the blower in accordance with the following formula, and to control the blower such that the fan rotation speed matches the target fan rotation speed, further comprising: means for outputting a fan motor current value of the blower And a gas proportional valve control means for controlling an energizing current value of the gas proportional valve according to the fan motor current value output by the fan motor current value output means. 2. A gas combustion appliance, comprising: a gas proportional valve for controlling the amount of combustion of the gas combustion appliance; and a blower for supplying air for combustion of the gas combustion appliance, wherein a set combustion amount of the gas combustion appliance is provided. The target value of the fan motor voltage of the blower is determined according to the following formula, and the fan is controlled so that the fan motor voltage matches the target value.Furthermore, the fan motor current value of the blower is output. And a gas proportional valve control means for controlling an energizing current value of the gas proportional valve according to the fan motor current value output by the fan motor current value output means. 3. A gas combustion appliance, comprising: a gas proportional valve for controlling a combustion amount of the gas combustion appliance; and a blower for supplying air for combustion of the gas combustion appliance, wherein a set combustion amount of the gas combustion appliance is provided. The target value of the fan motor current of the blower is determined according to the following formula, and the fan is controlled so that the fan motor current matches the target value.Furthermore, the fan motor current value of the blower is output And a gas proportional valve control means for controlling an energizing current value of the gas proportional valve according to the fan motor current value output by the fan motor current value output means. 4. A combustion amount of a gas-fired appliance is calculated and set based on a temperature difference between a tapping temperature and a set temperature.
The combustion device according to claim 1, 2 or 3.