JPH10238767A - Combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustor in which the generation of a negative pressure combustion in a room and the release thereof can be surely detected. SOLUTION: The electric current of a flame rod 16 is detected by a flame current sensor 35. An upper side threshold and a lower side threshold are given to a data storage part 36. A sensing data set part 42 changes and sets the upper side threshold and lower side threshold in response to the kind of gas or the amount of heat of combustion monitored by a combustion heat monitoring part 34. A negative pressure combustion condition sensor 37 outputs a negative pressure sensing signal, when a flame current sensing value sensed by the sensor 35 exceeds the upper side threshold and outputs a negative pressure release signal when the flame current sensing value downwardly passes the lower side threshold. A reporting means 45 separates and reports the negative pressure sensing signal and negative pressure release signal. A negative pressure mode operation control part 44 receives the negative pressure sensing signal to conduct a negative mode operation control such as air quantity up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion device such as a water heater.

[0002]

2. Description of the Related Art As shown in FIG. 10, a combustion device such as a water heater is often installed and used indoors. A CO sensor 28 for detecting the concentration of CO in the exhaust gas is provided on the exhaust side of the vehicle, and combustion safety means such as stopping combustion when the CO sensor 28 detects a dangerous value of CO is provided.

[0003]

Incidentally, recent houses have excellent indoor airtightness. When the ventilation fan 2 and the range hood are driven, the interior of the house becomes negative pressure. When the first combustion operation is performed, the amount of air in the supply / exhaust air becomes insufficient, and the problem that the combustion state deteriorates has been newly highlighted.

A method of detecting a negative pressure in a room by providing a negative pressure sensor in the room has been proposed in Japanese Patent Application Laid-Open No. 4-165200, but a sensor dedicated to negative pressure detection must be separately prepared. In addition, the cost of the device increases, and the configuration of the device becomes complicated. In addition, when the negative pressure detection sensor is installed at a position distant from the combustion device, the signal of the negative pressure sensor generates the combustion of the combustion device. It is doubtful or one that accurately reflects the environment.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a dedicated negative pressure sensor for measuring the degree of negative pressure in a room when a combustion device such as a water heater is used indoors. It is an object of the present invention to provide a combustion device capable of reliably performing detection without providing, and accurately performing a combustion operation in a negative pressure mode such as an air volume control corresponding to a degree of indoor negative pressure.

[0006]

In order to achieve the above object, the present invention takes the following measures. That is,
According to a first aspect of the present invention, there is provided a flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and an air volume control unit for controlling a fan air volume according to a burner combustion amount. In a combustion device provided with
A data storage unit in which an upper threshold value of the frame rod current is given as negative pressure detection data, a frame current detection unit that detects the frame rod current, and a detection value of the frame rod current as a frame current detection value When the flame current detection value exceeds the upper threshold value, a negative pressure combustion state detection section that outputs a negative pressure detection signal when the flame current detection value exceeds the upper threshold value is provided as means for solving the problem.

A second invention provides a flame rod for detecting a flame of a burner and outputting a flame rod current.
In a combustion device including a combustion fan that supplies and exhausts burner combustion and an air flow control unit that controls a fan air flow according to a combustion amount of the burner, a lower threshold value of the frame rod current is negative pressure release detection data. A data storage unit, a frame current detection unit for detecting the frame rod current, and a detection value of the frame rod current taken as a frame current detection value, and the frame current detection value falls below the lower threshold value. And a negative pressure combustion state detection unit that outputs a negative pressure release detection signal when the pressure exceeds the negative side.

Further, a third invention provides a flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and controlling a fan air flow according to a combustion amount of the burner. A data storage unit in which the flame rod current rise change reference value is provided as negative pressure detection data, a flame current detection unit that detects the flame rod current, and a flame. A negative pressure combustion state detection unit that takes in the detected value of the rod current as a flame current detection value and outputs a negative pressure detection signal when the rising change amount of the flame current detection value exceeds the rising change reference value. It is a means to solve the problem.

Further, a fourth aspect of the present invention provides a flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and controlling a fan air flow according to a combustion amount of the burner. In the combustion device provided with an air volume control unit that performs, a data storage unit in which the reference value for the downward change in the flame rod current is given as negative pressure release detection data, and a frame current detection unit that detects the flame rod current, A negative pressure combustion state detecting unit that captures a detected value of the flame rod current as a flame current detected value, and outputs a negative pressure release detection signal when a decreasing change amount of the flame current detected value exceeds the descending change reference value. It is a means to solve the problem with the configuration.

In a fifth aspect of the present invention, a flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying and exhausting burner combustion, and controlling a fan air flow according to a burner combustion amount. A data storage unit in which an upper threshold value of the flame rod current is given as negative pressure detection data, and a lower threshold value is given as negative pressure release detection data. A frame current detection unit that detects the frame rod current, and captures a detected value of the frame rod current as a frame current detection value, and outputs a negative pressure detection signal when the frame current detection value exceeds the upper threshold value. The problem is solved by a configuration including a negative pressure combustion state detecting unit that outputs a negative pressure release detection signal when the negative threshold value is exceeded. It is a means.

Further, in a sixth aspect of the present invention, a flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and controlling a fan air flow according to a burner combustion amount. A data storage unit in which a reference value for rising change of the flame rod current is given as negative pressure detection data, and a reference value for falling change of the flame rod current is given as negative pressure release detection data. A frame current detection unit that detects a flame rod current, and captures a detected value of the frame rod current as a frame current detection value, and outputs a negative pressure detection signal when a rising change amount of the frame current detection value exceeds the rising change reference value. A negative pressure combustion state detection unit that outputs a negative pressure release detection signal when the descending change amount exceeds the descending change reference value. It is a means to solve the problems with the formation.

Further, a seventh aspect of the present invention is directed to the first to sixth aspects.
In the apparatus having the configuration of any one of the inventions, the upper limit value and the lower limit value of the flame rod current given to the combustion heat amount and the designated value of the combustion heat amount are set, and the negative pressure combustion state detection unit detects the negative value. The output of the pressure detection signal and / or the negative pressure release detection signal is performed when the amount of combustion heat is equal to or less than the specified value and the flame rod current is output within a range surrounded by the upper limit value and the lower limit value. Is a means to solve.

Further, an eighth invention is directed to the fifth or sixth aspect.
Alternatively, in the apparatus having the configuration of the seventh invention, the negative pressure detection data and the negative pressure release detection data are given as variable data in accordance with the magnitude of the combustion heat of the burner, and are used to detect the combustion heat of the burner. The present invention is a means for solving the problem with a configuration in which a detection data setting unit for setting the negative pressure detection data and the negative pressure release detection data is provided.

Further, a ninth invention is directed to the fifth or sixth invention.
Or, in those provided with the configuration of the seventh or eighth invention,
The burner is burned using gas as fuel, and negative pressure detection data and negative pressure release detection data are given for each gas type of fuel, and a gas type setting unit for setting a gas type to be used is provided. The gas type setting information is taken in, and negative pressure detection data and negative pressure release detection data are set according to the type of gas to be used.

In a tenth aspect based on the ninth aspect, the gas type setting section is formed by a gas type changeover switch, and the gas type changeover switch is operated in conjunction with the gas type changeover switch. This is a means for solving the problem by adopting a configuration in which the negative pressure detection data and the negative pressure release detection data according to the type are set by the detection data setting unit.

Further, an eleventh invention is directed to the fifth or eighth invention.
Or, in those provided with the configuration of the ninth or tenth invention,
A time measuring unit is provided, and a reference time for negative pressure detection and negative pressure release detection is given in advance to the data storage unit, and the negative pressure combustion state detecting unit detects all the reference time periods for the negative pressure detection. When the frame current detection value exceeds the upper threshold value which is the negative pressure detection data over a period of time, the negative pressure detection signal is sent to the lower pressure which is the negative pressure release detection data over the entire section of the judgment reference time for negative pressure release detection. The configuration is such that a negative pressure release detection signal is output when the threshold value is exceeded, thereby solving the problem.

Further, the twelfth invention is directed to the sixth or seventh embodiment.
Alternatively, in the apparatus having the configuration of the eighth, ninth, or tenth aspect, a time measuring means is provided, and a reference time for negative pressure detection and negative pressure release detection is given to the data storage unit in advance and the negative time is provided. The pressure-combustion-state detecting unit outputs a negative pressure detection signal when the amount of increase in the flame current detection value within the judgment reference time for negative pressure detection exceeds the reference value of the upward change. The configuration is such that a negative pressure release detection signal is output when it exceeds the threshold value, which is a means for solving the problem.

Further, the thirteenth invention is characterized in that the eighth to twelfth inventions
In the apparatus having the configuration of any one of the inventions described above, a delay time from when the combustion heat amount change command is issued to when the flame rod current change corresponding to the change in the combustion heat amount is taken into the frame current detection unit is anticipated. Data of the system delay time is given in advance, the negative pressure combustion state detecting unit detects the frame current detected at the present time and the negative pressure detection data corresponding to the combustion heat amount at the time before the current time by the system delay time and This is a means for solving the problem by adopting a configuration for comparing with negative pressure release detection data.

Further, a fourteenth aspect of the present invention is the one provided with the configuration of the thirteenth aspect, wherein the combustion heat amount of the burner is monitored, and the system delay time is changed in a direction to increase as the combustion heat amount increases. This is a means for solving the problem with a configuration in which a system delay time change setting unit is provided.

Further, a fifteenth aspect of the present invention is the apparatus according to the twelfth aspect, wherein the frame rod current take-in delay from the output of the frame rod current by the frame rod to the detection by the frame current detection unit. The time is given in advance, and the negative pressure combustion situation detecting unit is more than the current time when the rising change reference value of the flame rod current is given as the negative pressure detection data and the falling change reference value is given as the negative pressure release detection data. The time instant before the flame rod current capture delay time is the reference point, and the frame current detection value captured at the current time and the frame current of the frame rod current output from the frame rod within the determination reference time earlier than the reference point. The detected change is compared with the current change in frame current detected value that exceeds the change reference value within the judgment reference time. This is a means for solving the problem by outputting a negative pressure detection signal when a negative pressure has occurred, and outputting a negative pressure release detection signal when a downward change below a downward change reference value has occurred.

Further, the sixteenth invention is directed to the fifth to fifteenth aspects.
In one of the above configurations, when one of the negative pressure detection signal and the negative pressure release detection signal is output, the other signal is output until the cancellation time given in advance from the signal output time elapses. This is a means for solving the problem with a configuration in which a reverse signal output canceling unit for stopping the signal output on the side is provided.

Further, a seventeenth invention is directed to the first to sixteenth aspects.
Monitoring the change in the amount of combustion heat, and when the change in the amount of combustion heat exceeds a predetermined heat amount change set value, the change in the amount of combustion heat falls within a predetermined allowable range. This is a means for solving the problem with a configuration in which a negative pressure condition detection interrupting unit for interrupting the operation of the negative pressure combustion condition detecting unit is provided.

Further, an eighteenth invention is directed to the first to seventeenth aspects.
A negative pressure mode operation control unit that performs a predetermined negative pressure mode operation when a negative pressure detection signal is output from the negative pressure combustion state detection unit. It is a means to solve the problem with the configuration described.

Further, a nineteenth invention is directed to the first to eighteenth embodiments.
The present invention has a configuration in which a notifying means for notifying the negative pressure combustion state is provided while the negative pressure detection signal is output from the negative pressure combustion state detection unit. It is a means to solve.

In a twentieth aspect based on the nineteenth aspect, the negative pressure combustion condition detecting section detects a negative pressure in accordance with an excess of the flame current detection value exceeding the negative pressure detection data. A signal is output, and the notifying means is configured to take in the information of the negative pressure detection signal and to discriminate and notify the degree of the negative pressure combustion, thereby solving the problem.

Further, a twenty-first invention is directed to the sixth or twelfth invention.
Alternatively, in the apparatus having the configuration according to the eighteenth, nineteenth, or twentieth invention, a CO sensor for detecting the CO concentration in the exhaust gas is provided on the exhaust side of the combustion device. As the CO concentration detected by the CO sensor increases, a fan air volume control data switching control unit that switches the fan air volume control data to the air volume increasing side is provided, and the fan air volume control data switching control unit increases the CO concentration. In addition to the basic function of switching the fan airflow control data to the airflow-up side, the fan rod airflow control data is switched to the airflow-up side when the frame rod current exceeds the preset upper threshold value. When the preset lower threshold is exceeded, the fan air volume control data is switched to the air volume down side. Function to switch the fan air flow control data to the air flow up side when the rising change amount of the frame rod current exceeds the rising change reference value within the preset reference time, and the falling change amount of the frame rod current is One or more additional functions of a function of switching the fan air volume control data to the air volume down side when the descending change reference value is exceeded within a preset reference time are provided.
Means for solving the problem is that the fan air volume control data is switched and controlled by a combination of the basic function and the additional function during a combustion operation within a low combustion capacity range equal to or less than a specified value within the combustion heat amount control range.

In the present invention, the frame rod current output from the frame rod is detected by the frame current detector, and the detected frame current value is combined with the predetermined negative pressure detection data and negative pressure release detection data. Be compared. When the flame current detection value exceeds the negative pressure detection data, it is determined that the combustion environment is in a negative pressure state, and a negative pressure detection signal is output from the negative pressure combustion state detection unit. When the flame current detection value falls below the negative pressure release detection data, it is determined that the negative pressure state of the combustion environment has been eliminated, and a negative pressure release detection signal is output from the negative pressure combustion state detection unit.

When the negative pressure detection signal and the negative pressure release detection signal are output, the notification means notifies the combustion environment state. On the other hand, when the negative pressure detection signal is output, for example, the combustion fan When the fan air volume control data is switched in the air volume up direction and the negative pressure release detection signal is output, the operation in the negative pressure mode is performed such as switching the fan air volume control data of the combustion fan in the air volume down direction. .

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows a mechanical configuration of a combustion device according to an embodiment of the present invention. The combustion device of the present embodiment relates to a water heater,
The main body 4 of the water heater is accommodated therein. In addition,
An air supply port 5 is provided in the instrument case 3, and air is guided from the air supply port 5 to an air inlet 6 of the main body 4 through a filter (not shown).

The main body 4 has a combustion chamber 7.
A burner 8 such as a semi-bunsen burner that burns using primary air and secondary air is installed at the lower side of the fuel cell. A gas passage 10 is connected to the burner 8, and fuel gas is passed through the gas passage 10. Is supplied to the burner 8.

The gas passage 10 has an electromagnetic valve 1 for opening and closing the passage.
There is provided a proportional valve 13 for controlling the gas supply to the burners 8 based on the valve opening amount. The proportional valve 13 has a configuration in which the valve opening amount (gas supply amount), that is, the amount of combustion heat (combustion capacity) of the burner 8 is controlled in accordance with the magnitude of the valve opening drive current controlled and applied by the control device 14. Things.

An ignition plug 15 for igniting the burner 8 and a frame rod 16 for detecting a flame of the burner 8 are provided near the burner 8. This frame rod 16 is shown in FIG.
As shown in FIG. 3, the flame is generated at the height where the internal flame of the flame generated in the burner 8 comes into contact. When a voltage is applied to the frame rod 16, ions ionizing the internal flame propagate and the flame rod 16 The frame rod current flows through the grounding end 17 on the side. That is, the frame rod 16 functions as a flame detection sensor that outputs a flame rod current by coming into contact with the flame.

A hot water supply heat exchanger 18 is provided above the combustion chamber 7.
A hot water supply pipe 20 is connected to the inlet side of the hot water supply heat exchanger 18, and a hot water supply pipe 21 is connected to the outlet side of the hot water supply heat exchanger 18. This hot water supply pipe 21 is connected to an external pipe,
The external piping is guided to a desired hot water supply place such as a kitchen, and a hot water tap (not shown) is provided at an outlet side. In the figure,
Reference numeral 22 denotes a feedwater flow rate sensor that detects a feedwater flow rate, 23 denotes a feedwater temperature sensor that detects a feedwater temperature, 24 denotes a feedwater temperature sensor that detects a tapwater temperature, and 25 denotes a water quantity control valve that controls the feedwater flow rate.

On the upper side of the combustion chamber 7, a combustion fan 26 for supplying and exhausting burner combustion is provided. The rotation of the combustion fan 26 is detected by a fan rotation detection sensor 27.

A CO sensor 28 is provided in the exhaust passage on the downstream side of the combustion fan 26.
, The CO concentration in the exhaust gas is detected. When the water heater of this embodiment is installed indoors, an exhaust duct is connected to the outlet side of the exhaust passage 30,
As shown in FIG. 10, the exhaust gas is discharged outside the room.

A remote controller 31 is connected to the controller 14 by signal. The remote controller 31 includes a temperature setting device for setting a hot water supply temperature, and a display section for displaying appropriate information (for example, a hot water supply temperature and an error signal) from the control device 14.

FIG. 1 shows the main parts of the control device 14, and includes a combustion control unit 32, an air flow control unit 33, a combustion heat amount monitoring unit 34,
A frame current detection unit 35, a data storage unit 36, a negative pressure combustion state detection unit 37, a reverse signal output cancellation unit 38, a timer 39 as time measuring means, a system delay time change setting unit 40, Situation detection suspending unit 41 and detection data setting unit 42
, A gas type setting unit 43, and a negative pressure mode operation control unit 44.

The combustion control unit 32 controls the feed water temperature by remote control.
The total heat quantity obtained by adding the feedforward heat quantity required to increase the hot water supply set temperature set at 31 or the like and the feedback heat quantity for correcting the difference between the hot water supply temperature and the hot water supply set temperature is calculated, and the combustion heat quantity of the burner 8 is calculated. Controls the proportional valve current (valve opening drive current) to the proportional valve 13 so that the total amount of heat is obtained.

That is, the combustion control unit 32 is provided with combustion control data indicating the relationship between the proportional valve opening and the amount of combustion heat (combustion capacity) as shown in FIG. The proportional valve opening is controlled within the range of the combustion capacity between Max and the minimum combustion heat amount Min. For example, when the amount of combustion heat obtained by the calculation is P, the proportional valve opening is obtained as Q from the control data of FIG. 9, and the proportional valve current is supplied to the proportional valve 13 so that the proportional valve opening Q is obtained. It is controlled as much as possible. In the control data shown in FIG. 9, the proportional valve opening corresponding to the minimum amount of combustion heat is set to 0%, the proportional valve opening corresponding to the maximum amount of combustion heat is set to 100%, and the proportional valve opening is set to 0%.
A control mode is employed in which control is performed within the range of 100% to 100% to obtain a combustion heat amount within the range of the minimum combustion heat amount and the maximum combustion heat amount.

The air volume control unit 33 has air volume control data as shown in FIG. 8 and uses the control data of A to correspond to the proportional valve opening during normal combustion operation when the room is not under a negative pressure environment. The number of fan rotations (fan airflow) to be performed is obtained, and the rotation of the combustion fan 26 is controlled so as to obtain the fan rotation speed (fan airflow). By this air volume control, an air volume corresponding to the amount of combustion heat (gas supply amount) is obtained, and the combustion control in which the amount of combustion heat matches the amount of air is achieved.

The combustion calorie monitoring unit 34 monitors a control command value (computed value) of the proportional valve current supplied to the proportional valve 13, and constantly monitors the proportional valve current value during the combustion operation to monitor a change in the combustion calorie. And the monitoring result is set to the system delay time change setting unit 40.
Are added to the negative pressure condition detection interrupting unit 41 and the detection data setting unit 42, respectively.

The data storage unit 36 is constituted by a memory and stores negative pressure detection data, negative pressure release detection data, flame rod current take-in delay time data, and system delay time data. The negative pressure detection data is data serving as a criterion for detecting whether or not the room is in a negative pressure state during the combustion operation of the water heater, and the negative pressure release detection data is a negative pressure in the room. Is data that serves as a criterion for detecting that the state has been released from. In the present embodiment, the negative pressure detection data and the negative pressure release detection data are classified into two types, and at least one of the data is stored in the data storage unit 36.
The negative pressure detection data and negative pressure release detection data of the first class are given by the threshold value of the flame rod current.
In this case, an upper threshold value is given as negative pressure detection data, and a lower threshold value is given as negative pressure release detection data.

According to an experimental study by the present inventor, when the interior of the room becomes negative pressure and the amount of air supplied by the combustion fan 26 decreases when the flame rod is set at an appropriate position, the flame shown in FIG. As the flame rod current increased and, conversely, the negative pressure in the room was eliminated, the flame shrunk back to its original state, and the phenomenon that the flame rod current decreased was found.

For example, from the state where the flame rod 16 detects the external flame of the combustion flame shown in FIG. 11 when the combustion state is good, a negative pressure state is generated, and there is a shortage of air due to the negative pressure state. In the combustion state, both the outer flame and the inner flame extend, and the frame rod 16 detects the inner flame.

Since the external flame has a high electric resistivity and the internal flame has a low electric resistivity, the frame rod 16 is changed from the external flame detecting state to the internal flame detecting state due to the generation of the negative pressure state as described above. The electrical resistance decreases and the flame rod
The flame rod current value detected and output from 16 increases.

That is, in FIG. 3, for example, when the combustion is performed well with the combustion capacity within the low combustion capacity range lower than the combustion capacity (proportional valve opening degree) X, it is located in the outer flame and the negative pressure state When the combustion flame rises and the combustion flame rises, the frame rod 16 is attached to the height position located at the inner flame, so that the
The rising change of the flame rod current value detected and output from 16 becomes clearer, and the occurrence of the negative pressure state is detected earlier than the detection of the negative pressure state in the room based on the CO concentration in the exhaust gas. Can be.

By setting the mounting position of the frame rod 16 as described above, the frame rod current value increases when the room is in a negative pressure state. Therefore, when the frame rod current value increases, the room is in a negative pressure state. Can be detected. Focusing on this point, the lower threshold value of the flame rod current is given as negative pressure release detection data, and the upper threshold value larger than that is given as negative pressure detection data.

FIG. 3 shows an example of setting the data of the upper threshold value and the lower threshold value. In the example of FIG. 3, the upper threshold is given by an upper fixed threshold and an upper variable threshold, and the lower threshold is given by a lower fixed threshold and a lower variable threshold. The upper fixed threshold value and the lower fixed threshold value are given as fixed values that do not change depending on the proportional valve opening. In the present embodiment, a constant gas amount is supplied when the burner 8 is ignited, that is, Since point ignition is performed with a fixed proportional valve opening, fixed upper and lower thresholds are used at the time of point ignition, which means that the upper fixed threshold and lower fixed threshold are used. Is given.

The upper variable threshold value and the lower variable threshold value are used as threshold values after the point ignition, and these variable threshold values become larger as the proportional valve opening increases.
It is provided as data that changes in the direction of increase as the amount of combustion heat increases. The reason why the upper and lower threshold values are given in the form of variable data is based on the results of experiments that have confirmed that the flame rod current increases as the amount of combustion heat increases. In the example of FIG. 3, the upper threshold is given by a fixed threshold and a variable threshold, but may be given by one threshold, and the lower threshold is also fixed. And one of the variable threshold value and the variable threshold value.

The data of the second classification of the negative pressure detection data and the negative pressure release detection data is provided with a reference value of a rising change of the frame rod current as negative pressure detection data and a reference value of a falling change of the frame rod current is detected as a negative pressure release detection data. This is given as data. That is, when the interior of the room changes from the normal state to the negative pressure state, attention is paid to the fact that the flame elongates and the flame rod current rises and changes. The reference data is used to determine that the room has been released from the negative pressure state when the amount of decrease in the flame rod current exceeds the reference value of the decrease, and the data is stored. The unit 36 includes at least one of a pair of an upper threshold value and a lower threshold value of the first class and a pair of a rising change reference value and a falling change reference value of the second class as negative pressure detection data and negative pressure. Stored as release detection data.

The negative pressure detection data and negative pressure release detection data of each of these classes may be given without considering the gas type of the gaseous fuel to be used. However, it has been confirmed that the flame rod current value differs depending on the gas type (for example, the gas type 13A has a larger flame rod current than the gas type 12A). L ₁ (6B, 6C, 7A),
L ₂ (5A, 5B, 5AN), L ₃ (4A, 4B, 4
The values of the negative pressure detection data and the negative pressure release detection data are given for each gas type such as C), 6A, 5C, and LPG.

The proportional delay 13 is operated after the combustion control unit 32 outputs the control signal of the amount of combustion heat,
The combustion gas corresponding to the operation of the proportional valve 13 is ejected from the burner 8, the combustion flame is detected by the flame rod 16, and the flame time is detected by the flame current detection unit 35. For example, a value of 0.8 seconds is stored in the data storage unit 36 as the system delay time.

The frame rod current take-in delay time is a delay time until the frame rod current output from the frame rod is detected by the frame current detection unit 35. For example, the delay time is given a margin. For example
The value of 0.3 seconds is stored in the data storage unit 36.

The frame current detector 35 is a frame rod.
The frame rod current output from 16 is, for example, 0.1
It is captured and detected at a sampling interval of seconds, and the detected value is added to the negative pressure combustion state detection unit 37.

The system delay time change setting section 40 changes and sets the system delay time stored in the data storage section 36 according to the amount of combustion heat. In other words, the proportional valve 13 may have a difference in responsiveness of operation depending on the position of the valve opening. The system delay time is changed or set continuously or stepwise, for example, 1 second when the proportional valve opening is less than 40%, 0.8 second when the proportional valve opening is 40% or more and less than 70%,
When it is 70% or more and 100% or less, the system delay time is changed and set to a value corresponding to the amount of combustion heat, such as 0.8 seconds, and the value is added to the negative pressure combustion state detection unit 37. Note that the system delay time change setting unit 40 may be omitted in some cases.

The gas type setting section 43 is provided, for example, on a control board of the control device 14.
The gas type to be used is set.For example, a plurality of tact switches and the like may be provided, and the gas type to be used may be set by each tact switch, but in this embodiment, the gas type is provided in a normal water heater or the like. Type changeover switch that changes the gain of the proportional valve for each gas type (Japanese Patent Publication No. 57-3)
844) is used as the gas type setting unit 43. The gas type setting unit _{43, 13A, 12A, L 1 (} 6B, 6C,
7A), L ₂ (5A, 5B, 5AN), L ₃ (4A, 4
B, 4C), 6A, 5C, LPG, etc., are selected and set by operating a switch.

The detection data setting section 42 includes the gas type setting section
The gas type setting information of 43 is taken in, and from the negative pressure detection data and negative pressure release detection data for each gas type stored in the data storage unit 36, according to the gas type set in the gas type setting unit 43. Negative pressure detection data and negative pressure release detection data are selected in conjunction with the operation of the gas type changeover switch.
Further, negative pressure detection data and negative pressure release detection data corresponding to the amount of combustion heat detected by the combustion heat amount monitoring unit 34 are set.
For example, negative pressure detection data that changes depending on the amount of combustion heat (proportional valve opening) is given as the upper variable threshold in FIG.
When the negative pressure release detection data is given by the lower variable threshold value and the amount of combustion heat is R at the value of the proportional valve opening,
The value of P _P is set as the value of the upper variable threshold, the value of P _L is set as the value of the lower variable threshold. Similarly, when the negative pressure detection data and the negative pressure release detection data are given by the ascending change reference value and the ascending change reference value, the data value corresponding to the combustion heat amount (the value decreases slightly as the combustion heat amount increases). Is set in the detection data setting unit 42, and the set data is added to the negative pressure combustion state detection unit 37.

The negative pressure combustion status detecting section 37 takes in the detected value of the flame rod current (the detected value of the frame current) from the frame current detecting section 35 and releases the negative pressure detection data set by the detection data setting section 42 and the negative pressure release. Based on the detection data, it is detected whether or not the indoor combustion environment of the water heater is in a negative pressure state.
For example, when the negative pressure detection data is given by the upper threshold value and the negative pressure release detection data is given by the lower threshold value, as shown in FIG. It compares the current detection value F _a and the current from the system delay time T _S only previous upper threshold P _U1 and lower threshold point P _L1 of the frame current detection value F _a is the upper threshold value T When the value exceeds _U1, for example, it is determined that the ventilation fan or the range hood has been activated and the indoor combustion environment has reached a negative pressure state.
_{When the temperature} falls below _L1 , it is determined that the indoor combustion environment has returned to the negative pressure release state, for example, when the ventilation fan and the range hood have stopped.

When a gas amount control command, that is, a command signal of a proportional valve current value is output from the combustion control unit 32, an upper threshold value and a lower threshold value corresponding to the magnitude of the proportional valve current (combustion heat amount). Since the value of the value is set by the detection data setting unit 42, the upper threshold value and the lower threshold value are set without delay to the gas amount control command. Until the flame rod current at the time of the gas amount control command is detected by the frame current detection unit 35, a delay of the system delay time T _S is involved. This means that the data corresponding to the control command at the point in time before the delay time T _S has been fetched. Therefore, the frame current detection value F _A fetched at the present time is compared with the threshold value just before the time T _S. To do There.

If the current frame current detection value is compared with the current upper and lower threshold values without considering such a system delay time, for example, FIG.
In as when the gas amount control command is issued indicating Since flame current detection value F _A detected by the flame current detecting unit 35 at the present time exceeds the upper threshold P _U1 ',
Actually, there is a problem that the combustion environment is erroneously determined to be in a negative pressure state even when the combustion environment is not in a negative pressure state. In the present embodiment, in order to solve such a problem caused by the system delay time, the system delay time T _S is considered, and as described above, the frame current detection value detected at the present time and the system delay time are used. The indoor combustion environment state is detected by comparing the upper threshold value and the lower threshold value at the previous time.

Upon detecting the negative pressure combustion environment, a negative pressure detection signal is output immediately when it is determined that the flame current detection value has exceeded the upper threshold value at a point in time. The negative pressure release detection signal may be output immediately when it is determined that the value is lower than the predetermined value at one point in time. However, in the present embodiment, the time width for detecting the negative pressure state and the negative pressure release state is determined by the determination criterion. Given as time (this judgment reference time may be given at the same time or at different times for the upper threshold value and the lower threshold value), and all (or the average value) of the frame current detection values are When the upper threshold value is exceeded over the entire section of the determination reference time (for example, 0.5 seconds), a negative pressure detection signal is output, and all (or the average value) of the frame current detection values are determined by the determination reference time (for example, 0.1 second). Seconds) Over when had exceeded the lower side it is arranged to output a negative pressure releasing detection signal. In addition,
The data of the judgment reference time for negative pressure detection (judgment reference time for the upper threshold value) and the data for the judgment reference time for negative pressure release detection (judgment reference time for the lower threshold value) are given to the data storage unit 36 in advance. Negative pressure combustion status detector
It is good to have 37.

When the detection of the negative pressure combustion environment in the room is detected using the rising change reference value which is the negative pressure detection data and the lower change reference value which is the negative pressure release detection data, for example, as shown in FIG. A rising change reference value F _th1 (eg, 1.1 μA) and a judgment reference time (judgment reference time for negative pressure detection) T _th1 (eg, 0.6 seconds) given to the rising change reference value;
A negative pressure state and a negative pressure release state are determined and detected based on data of a falling change reference value F _th2 and a determination reference time (a determination reference time for negative pressure release detection) T _th2 given to the falling change reference value. . That is, the negative pressure combustion state detection unit 37
The frame current detection value is fetched from the frame current detection unit 35, and when the rising change amount of the frame current detection value exceeds the rising change reference value _Fth1 within the determination reference time _Tth1 , for example, the ventilation fan or the range hood is activated. It is determined that a negative pressure combustion environment state has occurred, and a negative pressure detection signal is output. If the amount of decrease in the flame current detection value exceeds the decrease reference value F _th2 within the determination reference time T _th2 , for example, Then, the ventilation fan and the range hood are stopped and the indoor combustion environment is determined to have released the negative pressure, and a negative pressure release detection signal is output. F _th1 and F _th2 may be fixed values, but within the range of the combustion amount 0 to X%, the judgment value is small on the large combustion amount side (X% side), and the judgment value is small on the small combustion amount side (0% side). The judgment value may be increased.

When the negative pressure combustion state is detected using the rising change reference value and the falling change reference value, similarly to the case where the negative pressure combustion environment state is detected using the threshold value, the system delay time is detected. In consideration of T _S , the flame current detection value detected at the present time may be compared with an ascending change reference value and a descending change reference value corresponding to the amount of combustion heat at a point in time preceding the system delay time T _S. The change amount of the rising change reference value and the falling change reference value with respect to the change is smaller than the upper threshold value and the lower threshold value, so that signal processing can be performed without considering the system delay time. , In which case,
In the present embodiment, signal processing is performed as follows.

That is, there is a delay time (for example, 0.1 to 0.2 seconds) from when the frame rod 16 outputs the frame rod current to when it is detected by the frame current detection unit 35. In this embodiment, this delay time is defined as Given the frame rod current take-in delay time _TG considered, as shown in FIG.
A time point earlier than the present time by a delay time _TG is set as a reference point, and a judgment reference time T _th (T _th1 ,
The frame rod current output from the frame rod in the section of T _th2 ) is determined, and specifically, the frame current detection value detected at the present time, that is, the frame rod current output from the frame rod earlier by _TG than the present time. The frame current detection value of the frame rod current is compared with the frame current detection value of the frame rod current output from the frame rod within the determination reference time _Tth . And the flame rod current value detected from the flame rod is larger than any of the flame rod current values output from the flame rod within the range of the time T _th (or larger than the average value), and the time T
_When the current value at the start point of _th1 exceeds the rising change reference value F _th1 , a negative pressure detection signal is output, and the detected frame current value detected at the present time is the time T before the reference point.
_th (T _th2 ), which is smaller than any of the flame rod current values output from the frame rod (or the average value at that time), and which is lower than the current value at the start point of the time T _th2 , the change reference value F _th2. , A negative pressure release detection signal is output.

The negative pressure combustion state detector 37 compares the flame current detection value with the upper and lower threshold values as described above, or compares the amount of change in the flame rod current with the reference value for ascending and descending. Then, the generation of the negative pressure and the release of the negative pressure in the indoor combustion environment are detected. In the present embodiment, the detection of the negative pressure and the release of the negative pressure is performed by detecting the flame rod current stably and with high sensitivity. A range of values, that is,
The flame rod current is controlled within a range surrounded by the upper and lower limits of the flame rod current which can be detected stably and with high sensitivity. Of course, without being limited to the range between the upper limit value and the lower limit value, the generation of the negative pressure and the release of the negative pressure may be detected by comparing the flame rod current with a threshold value or a change reference value.

According to the study of the inventor of the present invention, the range in which the shortage of air supply due to the negative pressure in the room caused by the activation of the ventilation fan or the range hood affects the combustion performance is remarkable on the low combustion heat (low combustion capacity) side. (Fire is easy to extinguish), and the effect is small in a region where the amount of heat of combustion is large. In consideration of this point, the mounting position of the frame rod electrode is set in advance within the control range of the combustion heat quantity (combustion capacity) (for example, a value of 0 to X% in the proportional valve opening), and the frame rod 16 It is set at a position where it goes into a flame or an outside flame (see FIG. 3), and the negative pressure combustion state detection unit 37 detects the generation of the negative pressure and the release of the negative pressure in the indoor combustion environment and the combustion heat quantity is low. A configuration in which the heat treatment is performed in the range of the amount of heat (low combustion capacity) may be employed.

The negative pressure condition detection interrupting section 41 is a combustion heat quantity monitoring section.
If the change in the amount of combustion exceeds a predetermined change in the amount of heat of combustion received from the monitoring signal of the amount of combustion heat from 34, the negative pressure combustion state detection unit 37 until the predetermined stop time elapses.
Interrupt the operation of. More specifically, as shown in FIG. 7, taking into account a delay time T _{D of,} for example, 0.1 second, at which the gas amount control command output from the combustion control unit 32 propagates on the circuit,
In a time of T _W judgment time from the reference point before T _D time from the current time (e.g., within 2.5 seconds), the difference between the maximum and minimum proportional valve opening degree corresponding to the heat of combustion is heat changes the set value (proportional valve opens (For example, 10% of the degree), the operation of the negative pressure combustion state detecting section 37 is interrupted.

This is because when the amount of combustion heat greatly changes beyond the set value of the amount of heat change, the change in the amount of combustion heat appears as a change in the flame rod current. It is impossible to distinguish whether the change is caused by the change in the combustion heat amount or the change in the combustion heat amount, and the change in the flame rod current due to the change in the combustion heat amount is the negative pressure generation (or the negative pressure release). In order to prevent misjudgment, when the change in the amount of heat of combustion exceeds the set value of the amount of change in heat, the negative pressure and the negative pressure release detection operation of the negative pressure combustion status detection unit 37 are controlled by the change in the proportional valve opening. Within the allowable range (for example, 3
% Fluctuation range), the operation of the negative pressure combustion state detection unit 37 is interrupted to prevent erroneous judgment due to the change in the amount of combustion heat.

The notifying means 45 discriminates and notifies the negative pressure detection signal output from the negative pressure combustion state detecting section 37 and the negative pressure release detection signal. For example, the notification means 45 is configured using a display unit or the like of the remote controller 31, and displays a negative pressure detection signal and a negative pressure release detection signal on the liquid crystal display screen of the display unit using different symbols or the like, or When a negative pressure detection signal is output from the negative pressure combustion status detection unit 37, the lamp is turned on or blinks to notify the lamp, and when the negative pressure release detection signal is output, the lamp is turned off. The detection signal and the negative pressure release detection signal are notified separately.

The negative pressure mode operation control section 44 switches the normal combustion operation mode to a predetermined negative pressure mode operation when the negative pressure detection signal is output from the negative pressure combustion state detecting section 37. . Various control modes can be adopted as the operation in the negative pressure mode. For example, as an operation mode in the first negative pressure mode, a change control of the fan airflow is performed. In this fan air volume change control, for example, as shown in FIG. 8, control lines C, B, D, and E are provided in a direction in which the fan air volume increases in addition to the control line A of the normal combustion control data. When the negative pressure detection signal is output during the combustion on the control line A, the fan air flow control line is shifted from A to, for example, the B control line in order to eliminate the shortage of the fan air flow. When the negative pressure detection signal is output again when the negative pressure detection signal is output again when the combustion is performed on the control line B, the control flow shifts to the control line D on the air flow increasing side. When the negative pressure release detection signal is output,
This is a control mode in which the air flow is returned to the control line on the air flow reduction side to perform air flow control.

As described above, when the negative pressure detection signal is output, by controlling the rotation of the combustion fan to increase the air flow, the shortage of air supply due to the negative pressure in the room is eliminated and the combustion is improved. Can be done.

As can be seen from the data shown in FIG.
At the minimum input (at the time of the minimum proportional valve opening degree), when the fan air volume control data of B to E is switched, the fan rotation speed changes greatly, whereas at the maximum input, the fan rotation speed does not change much. This is different from the general method of burning with a constant air-fuel ratio, and is uniquely found by the present applicant. In other words, the burner originally uses a burner that can be burned at the maximum input (rated input) and controls the air volume so that the burner does not disappear even if the fuel is reduced. In other words, this means that the lower the input (lower the amount of combustion heat), the less the air flow control is performed. In other words, in the correlation with a constant air-fuel ratio, the lines are parallel, but in the present application, the distance between the lines increases as the proportional valve opening decreases, and the distance between the lines decreases as the proportional valve opening increases. (Each line does not need to converge at one point, and the imaginary line of each line intersects somewhere in the direction of the large proportional valve opening).

In the second mode of operation in the negative pressure mode, as shown in FIG. 8, for example, the control range of the proportional valve opening is from the range of 0% to 100% to the range of 10% to 100%. Is cut to reduce the control range of the amount of combustion heat. When a negative pressure detection signal is output from the negative pressure combustion state detection unit 37, the control range of the combustion heat amount is narrowed by undercut so that the minimum opening of the proportional valve is increased. Even in the case where the pressure in the room is reduced, the flame of the burner 8 is prevented from going out due to insufficient air volume.

The operation mode of the third negative pressure mode is the burner 8
In this case, the ignition is started on the control line on the airflow increasing side when the combustion of the fuel is started. For example, in the normal operation, the ignition is performed on the line of the air flow control data A in FIG. 8. For example, a negative pressure detection signal is output from the negative pressure combustion state detection unit 37 during the previous combustion operation before the combustion is stopped. When the control is performed, the ignition operation is performed on the control line B on the air flow increasing side. In this manner, by performing ignition on the side where the air volume is increased, it is possible to prevent an ignition error due to insufficient air supply and to reliably perform ignition.

The fourth operation mode in the negative pressure mode is a water heater having a function of stabilizing the re-watering temperature of the hot water heater.
This embodiment employs a control mode in which the number of revolutions of the combustion fan during the post-purge period after stopping the combustion is increased toward the air flow increasing side. After the stoppage of the hot water supply, the combustion fan 26 is continuously rotated for a predetermined time after the stoppage of the hot water supply in order to reliably exhaust the exhaust gas in the combustion chamber 7. The heater estimates the degree of cooling of the hot water temperature in the hot water supply heat exchanger 18 due to the rotation of the combustion fan during the post-purge period, and takes into account the conditions of the fan cooling to control the control of the re-starting hot water temperature. However, in an environment where the room is under negative pressure, even if the combustion fan 26 is rotated at the same fan speed, the air flow decreases, so the degree of cooling of the hot water supply heat exchanger 18 is small. As a result, a deviation occurs in the control constant for re-stabilizing hot water temperature.

In the fourth negative pressure mode operation mode, when the negative pressure detection signal is output from the negative pressure combustion status detecting section 37 before the previous hot water supply combustion operation is stopped, the combustion fan in the post-purge period is output. By increasing the rotation to the side where the air volume is increased, the decrease in the air volume due to the negative pressure in the room is compensated, and the same air volume as that of the normal combustion fan when the room is not in the negative pressure state is obtained. It is possible to prevent a deviation of the control constant of the tapping water temperature stabilization, and to prevent instability of the tapping water temperature due to indoor negative pressure.

The negative pressure mode operation control section 44 controls the negative pressure mode operation mode via the combustion control section 32 and the air volume control section 33 in accordance with a predetermined negative pressure mode operation mode. The reverse signal output cancel unit 38 monitors the output status of the negative pressure detection signal and the negative pressure release detection signal output from the negative pressure combustion status detection unit 37, and outputs one of the negative pressure detection signal and the negative pressure release detection signal. Is output, the signal output on the other side is stopped until the cancel time given in advance elapses. When the negative pressure mode operation is performed by the negative pressure mode operation control unit 44 according to the signal output of the negative pressure combustion state detection unit 37, for example, during the hot water supply combustion operation, the ventilation fan or the range hood is activated, and the indoor pressure is reduced. When the negative pressure detection signal is output from the negative pressure combustion state detection unit 37 and the negative pressure mode operation control unit 44 controls the combustion fan to change to the air flow increasing side, the flame rod current decreases. Negative pressure combustion status detector
37 outputs a negative pressure release detection signal.

By the output of the negative pressure release detection signal, the fan speed is returned to the original state before the air volume was increased. However, if the ventilation fan or the range hood is driven, the shortage of the air supply again immediately thereafter. As a result, a hunting phenomenon occurs in which the negative pressure detection signal and the negative pressure release detection signal are alternately output within a short time, such that the negative pressure detection signal is output again from the negative pressure combustion state detection unit 37, By providing the reverse signal output canceling unit 38, when one of the negative pressure detection signal and the negative pressure release detection signal is output, the output of the other signal is canceled until the cancellation time elapses. Since the output is stopped, the hunting phenomenon can be prevented, and the combustion control can be stabilized.

Next, the operation of the water heater of this embodiment will be briefly described. First, the water tap is opened and the water supply flow sensor
When running water is sensed by 22, the combustion fan 26 rotates. When the fan rotation speed reaches a predetermined rotation speed, discharge of the igniter electrode (not shown) starts, the electromagnetic valves 11 and 12 are opened, the proportional valve 13 is opened, and fuel gas is supplied to the burner 8. Then, the gas ejected from the burner 8
The ignition operation by 15 is performed, and the burner 8 is ignited. The amount of combustion heat of the burner 8 is controlled by the combustion control unit 32 of the control device 14 so that the supply water temperature becomes the set hot water supply temperature, and the hot water produced by the hot water supply heat exchanger 18 is guided to a desired hot water supply place such as a kitchen. Then, the hot water is used.

During the combustion operation, the flame rod current output from the flame rod 16 is applied to the flame current detector.
The detected value of the flame current is detected at 35 and is applied to the negative pressure combustion state detecting section 37.

As described above, the negative pressure combustion situation detecting section 37 compares the flame current detection value with the negative pressure detection data and the negative pressure release detection data, and determines whether the indoor combustion environment is in a negative pressure state or not. A negative pressure detection signal is output when it is determined that the vehicle is in the negative pressure state, and a negative pressure release detection signal is output when it is determined that the vehicle is not in the negative pressure environment state.

The negative pressure detection signal and the negative pressure detection release signal output from the negative pressure combustion status detecting section 37 are notified separately by the notification means 45. On the other hand, when the negative pressure mode operation control section 44 outputs a negative pressure detection signal from the negative pressure combustion state detection section 37, the control of the predetermined negative pressure mode operation mode is performed.

During the combustion operation, the CO concentration in the exhaust gas is detected by the CO sensor 28, and when the detected value of the CO concentration reaches the predetermined CO danger value, the safety against CO such as the stop of combustion is determined. Perform the operation.

Incidentally, the fan air volume control data is shown in FIG.
As shown in FIG. 13, in addition to the fan air flow control data of X = 0 corresponding to the fan air flow control data A of FIG. It may be provided in the form of parallel control lines like control data.

Next, the operation mode of the first negative pressure mode will be described in more detail. The negative pressure mode operation control unit 44 has a fan air volume control data switching control unit 50,
The fan air volume control data switching control unit 50 receives signals from the CO sensor 28 and the negative pressure combustion state detecting unit 37,
The fan air volume control data used by the air volume control unit 33 is used to determine the CO concentration detected by the CO sensor 28 and the frame rod.
The fan air volume control data is switched and controlled in accordance with the negative pressure state of the indoor combustion environment detected by the negative pressure combustion state detection unit 37 based on the 16 currents, and has one or more of the following functions.

The first function is a function of switching and setting the fan airflow control data to the fan airflow increasing side stepwise as the CO concentration detected by the CO sensor 28 increases. An operation example of this function will be described with reference to the flowchart of FIG. 13. First, at step 101, it is determined whether or not the CO concentration is equal to or higher than the upper limit value. Enhanced. In this flowchart, the fan air volume control data shown in FIG. 12 is described as an example, and the number X in the flowchart corresponds to the X value of each fan air volume control data shown in FIG.

Note that the upper limit of the CO concentration may be given as a time to reach the dangerous CO concentration when a person is exposed to the atmosphere having the CO concentration detected by the CO sensor 28, or , A high CO concentration threshold,
Alternatively, assuming that a person has been exposed to the atmosphere having the CO concentration detected by the CO sensor 28, the CO
The concentration may be obtained and given as the upper limit of the integrated value of the ratio t / T of the blood hemoglobin CO concentration calculated per unit time t to the dangerous arrival time T and the unit time t.

If the CO concentration is less than the upper limit value in step 101, it is determined in step 103 whether the CO concentration is equal to or less than the specified value. Switch to At this time, at step 105, the fan air volume control data is set to X = 0.
It is determined whether or not the data of the fan air volume control data is X = 0.
The fan air volume is set to the data of X = 1 one step higher than the data of 0.

In step 107, it is determined whether or not the value of X = 5 has been reached by switching the fan air volume control data to the one-stage air volume increasing side in step 102. Even if the air volume is increased, the prevention of generation of high-concentration CO gas cannot be expected.
At 108, the combustion is stopped.

If X does not reach 5 in step 107, the fan speed (fan air volume) corresponding to the combustion volume (combustion heat volume) is determined based on the fan air volume control data in which the air volume is increased by one step in step 102. At step 110, the value of X is registered as the negative pressure intensity in the room by rotating the combustion fan. In step 111, it is determined whether an ON signal is supplied from the feedwater flow sensor 22. When the ON signal is supplied, the operation from step 101 is repeated. On the other hand, when an off signal is output from the feedwater flow sensor 22, it is determined that the hot-water tap is closed, and the combustion is stopped. Then, in step 112, the elapsed time from when the combustion was stopped is measured using a timer or the like, and it is determined whether or not the time is within 10 minutes after the stop of the combustion. When the combustion operation is restarted within 10 minutes after the combustion is stopped, the negative pressure state in the room becomes the above-described step 11
0, it is assumed that the value is the same as the registered X value, and the combustion operation is performed using the fan air volume control data of the registered X value. The fan air volume control data of X = 0, which is the fan air volume control data, is set to prepare for the next combustion operation.

In the flowchart shown in FIG. 13, when a negative pressure is generated in the room, a shortage of air supply occurs, and the CO concentration increases in accordance with the degree of the negative pressure in the room.
Detects an increase in the O concentration, selects and designates fan air volume control data according to the intensity of indoor negative pressure, eliminates insufficient air supply due to negative pressure in the room, and performs good combustion operation. .

The second function of the fan air volume control by the fan air volume control data switching control unit 50 is a negative pressure combustion state detecting unit.
According to 37, when negative pressure detection or negative pressure release detection is performed using the upper threshold value and the lower threshold value, the fan air volume control data is received in response to the negative pressure detection signal or negative pressure release detection signal. This is a function to set switching. That is, the fan air volume control data switching control unit 50 performs the operation of the second function when the frame rod current exceeds the upper threshold value and a negative pressure release detection signal is applied from the negative pressure combustion state detection unit 37. Then, it is determined that the room is in a negative pressure condition, and the fan air volume control data is switched to the air volume up side, and the frame rod current falls below the lower threshold value (exceeds below).
When a negative pressure release detection signal is applied from the negative pressure combustion status detection unit 37, it is determined that the negative pressure in the room has changed in the release direction, and the fan air volume control data is switched to the fan air volume down side.

FIG. 14 is a flowchart showing the operation of the second function of the fan air volume control data switching section 50 together with the operation of the negative pressure combustion state detecting section 37. That is, step
At 201, the negative pressure combustion state detecting section 37 determines whether or not the frame rod current has exceeded the upper threshold, and when the flame rod current has exceeded the upper threshold, the fan air flow control data switching control section 50 sends the fan air flow control data to the fan. Similarly, when it is determined in step 203 that the frame rod current has exceeded the lower threshold value, it is determined that the negative pressure condition in the room has been released, and the fan air volume control is performed. The data is switched and set to the one-step fan air volume down side. The up / down switching operation of the fan air volume control data is the same as the operation of the flowchart shown in FIG. 13, and the same operations are denoted by the same step numbers and overlapping description will be omitted.

A third function of the fan air volume control configuration by the fan air volume control data switching control unit 50 is that the negative pressure combustion state detection unit 37 uses the frame rod current rising and falling reference values to reduce the negative pressure. When the detection or the negative pressure release detection is performed, the function is to switch and set the fan air volume control data in response to the negative pressure detection signal or the negative pressure release detection signal. That is, the fan air volume control data switching control unit
50, as shown in FIG. 4, the rising change amount of the flame rod current is within the reference time T _th1 and the rising change reference value F
_{When the} pressure exceeds _th1 , the negative pressure combustion state detecting unit 37 detects the negative pressure release signal from the detecting unit 37. Is determined to be a negative pressure, and the fan air volume control data X is switched and set to the air volume up side ((X + 1) side).

Further, the fan air volume control data switching control unit 50 determines that the negative pressure combustion state detecting unit detects that the decreasing change amount of the frame rod current exceeds the descending change reference value _Fth2 within the determination time _Tth2. 37
When the negative pressure release detection signal is added from 37, it is determined that the indoor negative pressure state has been released (or changed in the negative pressure decreasing direction), and the fan air flow control data X is output to the fan air flow down side ((X-1 ) Side). In addition, A, B, and D of the frame rod current in FIG.
Corresponds to the current value at the point position.

The fan air volume control data switching control unit
When the fan air volume control data is set to be switched by any of the functions according to 50, the air volume control unit 33 controls the air volume of the combustion fan 26 using the switched fan air volume control data.

The fan air volume control data switching control unit 50 is provided with one or more of the above-mentioned functions to set the fan air volume control data according to the negative pressure in the room. In a low combustion capacity range in which the amount of combustion heat (proportional valve opening) is, for example, less than a specified value in the control range (for example, 30% in proportional valve opening), the combustion performance is more easily affected by the negative pressure in the room. In the capacity range, CO
The first function (basic function) based on the CO detection signal of the sensor and the one or more functions (additional function) based on the frame rod current are combined, and the fan airflow based on the detection of about the negative pressure in the room by the CO sensor By using both the control data setting and the switching setting of the fan air flow control data based on the detection of the indoor negative pressure level by the frame rod current, more accurate fan air flow control according to the indoor negative pressure level can be performed. .

That is, in a region where the amount of heat of combustion is low (proportional valve opening is small), if CO is collected by a CO sensor to detect the deterioration of combustion due to deterioration of combustion due to insufficient air volume, the deterioration of combustion is detected. It takes time from the generation of CO to the detection by the CO sensor, and there is a possibility that a fire may occur during this time. In this regard, the flame rod current instantaneously reacts to the deterioration of combustion, and the change of the flame rod current is used to quickly detect the deterioration of combustion, and the amount of air is quickly controlled in the direction of improving combustion to prevent misfire. . On the other hand, the flame rod has a relationship between the flame rod mounting position and the combustion amount at which the combustion deterioration can be detected with high sensitivity. When the combustion amount is out of this range, the detection sensitivity of the combustion deterioration is reduced. On the calorific value side), the deterioration of combustion can be detected satisfactorily by the CO sensor.
Negative pressure detection based on flame rod current on low input side (low combustion calorie side) and CO on high input side
By using the sensor together with the negative pressure detection based on the CO concentration detection signal, it is possible to accurately detect the negative pressure condition of the indoor combustion environment in the entire range of combustion calorie control, and to provide a more accurate fan according to the degree of the negative pressure in the room. Air volume control becomes possible.

By the way, in this embodiment, the burner 8 is constituted by a burner such as a semi-bunsen burner which burns using primary air and secondary air. By using this type of burner, the burner 8 shown in FIG. As shown in the figure, a region surrounded by the upper limit value and the lower limit value is formed. By detecting a change in the flame rod current in this region, the degree of negative pressure in the indoor combustion environment is detected with high sensitivity, and the degree of negative pressure is detected. It is possible to effectively control the fan airflow according to the condition.

On the other hand, when the burner 8 is constituted by an all-primary air combustion type burner, the flame rod current is a unique value determined by the air-fuel ratio with respect to the proportional valve opening as shown in FIG. In other words, the characteristic relation of the flame rod current to the proportional valve opening becomes one straight line,
A change region of the flame rod current surrounded by the upper limit value and the lower limit value as shown in FIG. 3 of the present embodiment does not occur, and therefore, as in the present embodiment, the change in the flame rod current is detected and the indoor It is impossible to judge the degree of the negative pressure and switch and control the fan air volume control data. In the present embodiment, as described above, the burner 8 is constituted by a burner of a type that uses primary air and secondary air to burn, and changes in a region surrounded by the upper limit and the lower limit of the flame rod current. By detecting the flame rod current, the degree of negative pressure in the room can be detected with high sensitivity, and based on this, an epoch-making effect of controlling the supply of air flow suitable for the negative pressure of the indoor combustion environment is achieved. Things.

Note that the present invention is not limited to the above-described embodiment, but can adopt various embodiments. For example,
In the above-described embodiment, the negative pressure detection signal and the negative pressure release detection signal output from the negative pressure combustion state detection unit 37 are notified by the notification unit 45, but the notification method is further developed, and the negative pressure When a negative pressure detection signal is output from the combustion state detecting section 37, the magnitude of the negative pressure may be discriminated and notified. In this case, the negative pressure combustion state detection unit 37
When the frame current detection value is compared with the negative pressure detection data, a negative pressure detection signal corresponding to the degree that the frame current detection value exceeds the negative pressure detection data, for example, the frame current detection value is negative pressure detection By outputting a negative pressure detection signal whose output voltage is increased according to the magnitude exceeding the data, the notifying unit 45 is configured to change the notification mode according to the voltage level of the negative pressure detection signal, The degree of the negative pressure can be notified separately.

Further, in the above embodiment, the detection of the negative pressure combustion state in the room is performed in the proportional valve opening section of 0 to X% of the combustion calorie control range. For example, as shown in FIG. Valve opening from 0% to X% or proportional valve opening from X%
It may be performed within the range of 100%. According to the examination of the experiment of the present inventor, it is difficult for a semi-bunsen (Bunsen) flame to cover the entire range of the control range of the calorific value with one frame rod (frame rod electrode).
When the external flame covers the frame rod at the time of 0 to X%, the flame rod No. 1 and the flame rod N is placed at a position where the external flame at normal time and the internal flame at negative pressure when X to 100%.
o. 2 is desirably installed. In addition, the CO sensor detects this due to a change in the negative pressure in the room, and extinguishes the fire before switching the fan airflow control data to the airflow up side to improve combustion. It is desirable to detect the negative pressure by using the reacting flame rod current and the detection signal of the CO sensor together. Further, in the range where the amount of combustion heat (proportional valve opening) is large, even if the combustion is not improved by the change in the flame rod current with respect to the negative pressure change, the fire does not immediately extinguish, and the combustion is improved by the CO sensor. We have obtained experimental results that are sufficient in time. Focusing on this point, CO combustion sensor can be improved within the range of small combustion heat (proportional valve opening) by improving the combustion by flame rod current that is sensitive to the negative pressure change in the room. It is desirable that the operation of the negative pressure combustion state detection unit 37 based on the flame rod current be used to take measures for improving the combustion before the fire is extinguished. In the study by the inventor of the above experiment,
A value of 30 is obtained as the value of X. When the proportional valve opening is within 30% or less, negative pressure detection using the flame rod current is used together with the negative pressure change in the room, and the proportional valve opening is 30%. For the portion exceeding%, only the CO sensor is used. Based on the results of this experiment, it is particularly effective to perform the operation of the negative pressure combustion state detection unit 37 in the range where the proportional valve opening is 30% or less.

Further, in the present embodiment, a description has been given by taking a water heater as an example of a combustion device.
The present invention is applied to various combustion devices other than a water heater using gas or oil as a fuel, for example, a bath kettle, a heating device, a cooling device, a cooling / heating device, a fan heater, a gas dryer, and the like.

Further, in the above embodiment, as shown in FIG. 2, the combustion fan 26 is provided on the exhaust side and is of the suction type. However, for example, the combustion fan 26 may be provided on the lower side of the burner 8 and may be of the extrusion type. .

Further, the fan air volume control data shown in FIG. 8 may be given by the relationship between the proportional valve opening and the fan speed, or may be given by the relationship between the proportional valve opening and the fan air volume. In the latter case, an air flow sensor (for example, a wind speed sensor) for detecting a fan air flow is provided, and a control mode for controlling the fan speed so that the detected air flow becomes a target air flow corresponding to the proportional valve opening is adopted.

Further, in the embodiment shown in FIGS. 13 and 14, when the fan air volume control data is sequentially increased to the air volume up side, X = 0, X = 1, X = 2, X = 3, X =
X is sequentially increased by 1 such as 4, and when the fan air volume control data is reduced to the air volume down side, X = 4.
X is successively decreased by one, such as X = 3, X = 2, X = 1, but the order of ascending and descending of these fan air volume control data is not necessarily limited to this. When increasing the control data, X =
0, X = 2, X = 3, X = 4 may be raised in the procedure.

Further, in this embodiment, the burner 8 is constituted by a burner such as a semi-bunsen type which burns by using primary air and secondary air. Since the rich burner receives the air from the light burner and burns, the combustion of the rich burner approximates the combustion mode of the semi-bunsen burner. Since the flame rod current can be changed within a relatively wide range between the upper limit and the lower limit in response, the burner 8 may be constituted by a gray burner.

[0108]

According to the present invention, the upper threshold value of the frame rod current is given as negative pressure detection data, the lower threshold value is given as negative pressure release detection data, and the flame rod current output from the frame rod is given. When the flame current detection value exceeds the negative pressure detection data (when it exceeds the negative pressure detection data), the combustion environment is determined to be in a negative pressure state and a negative pressure detection signal is output, and the flame current detection value is released from the negative pressure. When the detection data falls below (when the detection data falls below), a negative pressure release detection signal is output assuming that the negative pressure combustion state has been released. When a combustion device such as a water heater is burning, the ventilation fan and the range hood are activated, and it is possible to reliably detect that the indoor combustion environment has been reduced to a negative pressure. By being sealed, it is possible to reliably detect that the indoor combustion environment is negative pressure releasing.

Further, even in the invention in which the reference value of the change in the flame rod current is given as the negative pressure detection data and the reference value of the falling change is given as the negative pressure release detection data, the increase in the change amount of the flame current detection value increases. When the change reference value is exceeded (exceeds), the room is determined to be in a negative pressure combustion environment state and a negative pressure detection signal is output. When the amount of decrease in the flame current detection value exceeds the decrease change reference value, Since the negative pressure release detection signal is output as a release of the negative pressure combustion state in the room, the negative pressure detection data and the negative pressure release detection data are given by a threshold value. Similarly, it is possible to reliably detect the negative pressure state and the negative pressure release state of the indoor combustion environment.

In particular, by providing the negative pressure detection data and the negative pressure release detection data as the reference values for the rise and fall of the frame rod current, the negative pressure detection and the negative pressure open detection can be detected with high accuracy over a long period of time. The effect that it can be obtained is obtained. That is,
When the combustion apparatus is used for a long period of time, exhaust gas and the like become clogged with the exhaust gas, which acts in a direction to decrease the supply of air, so that the flame rod current gradually increases with aging. For this reason, when given by the negative pressure detection data and the negative pressure release detection data, the flame rod current moves toward the upper threshold value side, which is the negative pressure detection data, due to aging, and is the negative pressure release detection data. Since it gradually moves away from the lower threshold, the accuracy of negative pressure detection and negative pressure release detection may decrease.However, the negative pressure detection data and negative pressure release detection data are used to determine whether the flame rod current rises or falls. By providing the reference value, the negative pressure detection and the negative pressure release detection can be performed with high accuracy over a long period of time without being affected by such aging. .

Further, in the configuration in which the negative pressure detection data and the negative pressure release detection data are given as variable data corresponding to the amount of combustion heat of the burner, correct data can be obtained without being affected by the change of the combustion heat of the burner. Since the indoor negative pressure combustion environment state and the negative pressure release state can be detected, the detection accuracy of the combustion environment state can be improved.

Further, the invention has a configuration in which negative pressure detection data and negative pressure release detection data are given for each gas type of fuel, and negative pressure detection data and negative pressure release detection data are set according to the type of gas used. Therefore, negative pressure detection data and negative pressure release detection data can be set according to the type of gas used, so that regardless of the type of gas used at the destination, the negative pressure combustion state in the room and the negative pressure release combustion can be correctly set. The state can be detected.

Further, a reference time for comparing the detected frame current value with the negative pressure detection data and the negative pressure release detection data is provided, and the frame current detected value is negative over the entire section of the negative pressure detection reference time. The negative pressure detection signal is output when the pressure detection data exceeds the upper side, and the negative pressure detection signal is output when the frame current detection value exceeds the negative pressure release detection data over the entire period of the reference time for negative pressure release detection. The invention configured to output the release detection signal has an effect that the negative pressure combustion state and the negative pressure release state in the room can be accurately detected without being affected by sudden changes in the frame current such as noise. can get.

Similarly, a judgment reference time is given, and when the rising change amount of the frame current detection value within this judgment reference time exceeds the rising change reference value, the negative pressure detection signal is sent, and the falling change amount becomes the falling change reference value. In this case, the negative pressure release detection signal is output when the pressure exceeds the threshold value. Since the detection is performed, the negative pressure combustion state and the negative pressure release state can be accurately detected without being affected by sudden changes in the flame current detection value such as noise or momentary blackout.

Further, a delay time from when the combustion heat amount change command is issued to when the flame rod current change is captured by the frame current detection unit is given as a system delay time. In the invention configured to compare the negative pressure detection data and the negative pressure release detection data at a point in time just before the time,
Since the flame current detection value captured at the present time can be compared with the negative pressure detection data and the negative pressure release detection data corresponding to the amount of combustion heat at the time when the flame current detection current is output, the change in the flame rod current can be compared with the flame current detection value. The effect of being able to accurately detect the indoor negative pressure combustion state and the negative pressure combustion release state without being affected by the delay time until the air is taken into the chamber.

Further, in the invention in which the system delay time is changed according to the amount of combustion heat of the burner, the system delay time is accurately set according to the magnitude of the amount of combustion heat. By utilizing this, it is possible to more accurately detect the indoor negative pressure combustion state and the negative pressure combustion release state.

Further, when one of the negative pressure detection signal and the negative pressure release detection signal is output, the signal output on the other side is stopped until the cancellation time given in advance from the output of the signal. In the invention, the hunting phenomenon that the negative pressure detection signal and the negative pressure release detection signal are alternately output in a short time can be prevented, and the combustion control using the negative pressure detection signal and the negative pressure release detection signal can be prevented. Can be improved in stability.

Further, the change in the amount of combustion heat is monitored, and when the change in the amount of heat of combustion exceeds a predetermined change in the amount of heat, the operation of the negative pressure combustion state detection unit is continued until the change in the amount of heat of combustion falls within a predetermined allowable range. In the invention in which the combustion current is interrupted, the flame current detection value changes due to a large change in the amount of combustion heat, and this is erroneously determined to be a change in the flame current due to negative pressure release or negative pressure in the indoor combustion environment. The phenomenon can be prevented, and thereby the reliability of the detection of the negative pressure combustion state can be improved.

Further, in the invention in which the negative pressure detection data and the negative pressure release detection data are given by either the threshold value of the flame rod current or the change reference value, the negative pressure detection signal is output from the negative pressure combustion state detecting section. In this case, when the negative pressure detection signal is used as a trigger to perform a predetermined negative pressure mode operation, the combustion is performed in accordance with the occurrence of the negative pressure state in the room and the release of the negative pressure state. Since the control of the device can be improved, it is possible to eliminate the adverse effects caused by the change in the indoor combustion environment due to the generation and cancellation of the negative pressure combustion state in the room, and to operate the combustion device satisfactorily.

Further, when the negative pressure detection signal is output from the negative pressure combustion status detection section, the negative pressure combustion status is notified by the notification means. It is possible to notify the user of the negative pressure combustion state, and to urge the user to ventilate or not to uselessly drive the ventilation fan or the range hood. In particular, in the configuration in which the degree of the negative pressure in the negative pressure combustion state is notified separately, the user can be clearly notified of the degree of the negative pressure combustion state, so that the user can also use the negative pressure. It is convenient in use because measures can be taken according to the degree.

Further, the present invention is configured to use a flame rod to determine the state of negative pressure combustion and the state of negative pressure release. This flame rod is a general combustion sensor as a sensor for detecting the burner flame. Since this frame rod can be used as it is as a sensor to detect the occurrence and release of the negative pressure combustion environment, a special sensor for detecting the negative pressure combustion environment is installed. Therefore, there is an effect that the configuration of the present invention can be constructed with a simple configuration.

Further, the degree of indoor negative pressure is detected based on the CO concentration detection signal of the CO sensor and the flame rod current output from the frame rod, and the fan air volume control data is changed according to the degree of indoor negative pressure. The invention has a configuration in which a fan air volume control data switching control unit is provided for switching and setting the air volume upward direction when the degree of indoor negative pressure is large and in the air volume downward direction when the indoor negative pressure is released (or reduced). Since the fan airflow is controlled according to the degree of the negative pressure in the room, the insufficient air supply due to the negative pressure in the room is eliminated by increasing the airflow, and when the negative pressure in the room is released, the airflow is reduced. As a result, it is possible to perform a good combustion operation without being affected by a change in the negative pressure condition in the room. In particular, by using the detection of the degree of negative pressure in the room based on the CO concentration detection signal of the CO sensor and the detection of the degree of negative pressure in the room based on the flame rod current in combination, over the entire control range of the amount of combustion heat (combustion capacity). The degree of indoor negative pressure can be accurately detected, and more accurate fan air volume control according to the degree of indoor negative pressure can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main configuration of an embodiment of the present invention.

FIG. 2 is a system configuration diagram of an embodiment of a combustion device according to the present invention.

FIG. 3 is an explanatory diagram of a setting example of an upper threshold value and a lower threshold value in the embodiment.

FIG. 4 is an explanatory diagram showing an operation state of indoor negative pressure combustion detection and negative pressure release detection using a frame rod current rising reference value and a falling reference value in the embodiment;

FIG. 5 is an explanatory diagram showing a relationship between a frame current detection value and a threshold value in consideration of a system delay time in the embodiment.

FIG. 6 is an explanatory diagram showing a relationship between a delay time of capturing a frame rod current and a time width of a detected frame rod current in the embodiment.

FIG. 7 shows the amount of heat of combustion (proportional valve opening) in the embodiment.
FIG. 7 is an explanatory diagram showing a monitoring state of a change in the state.

FIG. 8 is an explanatory diagram of control data of a fan air volume showing a relationship between a proportional valve opening and a fan rotation speed.

FIG. 9 is an explanatory diagram of control data indicating a relationship between a proportional valve opening and a combustion heat amount.

FIG. 10 is an explanatory diagram of a state in which a combustion device such as a water heater is installed indoors.

FIG. 11 is an explanatory diagram of a detection state of a flame by a frame rod.

FIG. 12 is an explanatory diagram of another example of the fan air volume control data.

FIG. 13 is a flowchart of an operation of detecting an indoor negative pressure state based on the CO concentration and performing air volume control.

FIG. 14 is a flowchart of an operation of detecting an indoor negative pressure state based on a frame rod current and performing air volume control.

FIG. 15 is a characteristic diagram showing a relationship between a proportional valve opening and a frame rod current when an all-primary air combustion type burner is used.

[Explanation of symbols]

 16 Flame rod 34 Combustion calorie monitoring unit 35 Flame current detection unit 37 Negative pressure combustion status detection unit 38 Reverse signal output cancellation unit 41 Negative pressure status detection interruption unit 42 Detection data setting unit 44 Negative pressure mode operation control unit

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Masaharu Itagaki 3-4 Fukamidai, Yamato-shi, Kanagawa Prefecture Inside Gaster Co., Ltd. (72) Inventor Kikuo Okamoto 3-4 Fukamidai, Yamato-shi, Kanagawa Prefecture Gastar Corporation ( 72) Inventor Kazuyuki Iizumi 3-4 Fukamidai, Yamato City, Kanagawa Prefecture Inside Gaster Co., Ltd. (72) Inventor Akihiro Nirasawa 3-4 Fukamidai Yamato City, Kanagawa Prefecture Inside Gaster Co., Ltd. 3-4 Fukamidai, Yamato-shi

Claims (21)

[Claims] 1. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying and exhausting burner combustion, and an air volume control unit for controlling a fan air volume according to a burner combustion amount. In the equipped combustion device,
A data storage unit in which an upper threshold value of the frame rod current is given as negative pressure detection data, a frame current detection unit that detects the frame rod current, and a detection value of the frame rod current as a frame current detection value A combustion device comprising: a negative pressure combustion state detection unit that outputs a negative pressure detection signal when the flame current detection value exceeds the upper threshold value. 2. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying and exhausting burner combustion, and an air flow control unit for controlling a fan air flow in accordance with a burner combustion amount. In the equipped combustion device,
A data storage unit in which a lower threshold value of the frame rod current is given as negative pressure release detection data, a frame current detection unit that detects the frame rod current, and a frame current detection value And a negative pressure combustion state detection unit that outputs a negative pressure release detection signal when the flame current detection value exceeds the lower threshold value below. 3. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying and exhausting burner combustion, and an air flow control unit for controlling a fan air flow according to a burner combustion amount. In the equipped combustion device,
A data storage unit in which the reference value of the rise change of the frame rod current is given as negative pressure detection data, a frame current detection unit for detecting the frame rod current, and a detected value of the frame rod current as a frame current detection value A combustion apparatus comprising: a negative pressure combustion state detection unit that outputs a negative pressure detection signal when the amount of increase in the detected frame current exceeds the reference value of the increase. 4. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and an air volume control unit for controlling a fan air volume according to a burner combustion amount. In the equipped combustion device,
A data storage unit in which the reference value of the drop change of the frame rod current is given as negative pressure release detection data, a frame current detection unit that detects the frame rod current, and a detected value of the frame rod current as a frame current detection value A combustion apparatus comprising: a negative pressure combustion state detection unit that outputs a negative pressure release detection signal when a falling change amount of the fetched frame current detection value exceeds the falling change reference value. 5. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying / exhausting burner combustion, and an air volume control unit for controlling a fan air volume according to a burner combustion amount. In the equipped combustion device,
A data storage unit in which the upper threshold value of the frame rod current is provided as negative pressure detection data, and the lower threshold value is provided as negative pressure release detection data, and a frame current detection unit that detects the frame rod current. A negative pressure detection signal is obtained when the detected value of the frame rod current exceeds the upper threshold value, and a negative pressure detection signal is output when the detected frame current value exceeds the upper threshold value. A combustion device comprising: a negative pressure combustion state detection unit that outputs a pressure release detection signal. 6. A flame rod for detecting a flame of a burner and outputting a flame rod current, a combustion fan for supplying and exhausting burner combustion, and an air volume control unit for controlling a fan air volume according to a burner combustion amount. In the equipped combustion device,
A data storage unit in which the rising change reference value of the frame rod current is given as negative pressure detection data, and a falling change reference value is given as negative pressure release detection data, and a frame current detection unit that detects the frame rod current. The detected value of the flame rod current is taken as the detected value of the frame current, and when the rising change amount of the detected frame current value exceeds the rising change reference value, the negative pressure detection signal is output, and the falling change amount exceeds the falling change reference value. A combustion device including a negative pressure combustion state detection unit that sometimes outputs a negative pressure release detection signal. 7. An upper limit value and a lower limit value of a flame rod current given to a combustion heat amount and a designated value of the combustion heat amount are set, and a negative pressure detection signal and / or a negative pressure by a negative pressure combustion state detecting unit are set. 7. The output of the release detection signal according to any one of claims 1 to 6, wherein the output is such that the combustion heat amount is equal to or less than the specified value and the flame rod current is within a range surrounded by the upper limit value and the lower limit value. The combustion device according to claim 1. 8. The negative pressure detection data and the negative pressure release detection data are given as variable data corresponding to the amount of combustion heat of the burner, and the amount of combustion heat of the burner is detected to detect the negative pressure detection data and the negative pressure. 8. The combustion apparatus according to claim 5, further comprising a detection data setting section for setting release detection data. 9. The burner is burned using gas as fuel, negative pressure detection data and negative pressure release detection data are given for each gas type of fuel, and a gas type setting unit for setting a gas type to be used is provided. 7. A configuration in which the gas type setting information of the gas type setting section is fetched and negative pressure detection data and negative pressure release detection data are set according to the gas type used. Item 10. The combustion device according to Item 8. 10. The gas type setting unit is formed by a gas type changeover switch. Negative pressure detection data and negative pressure release detection data corresponding to the gas type are linked to the switch operation of the gas type changeover switch. The combustion device according to claim 9, wherein the combustion device is configured to be set by: 11. A time measuring means, a judgment reference time for negative pressure detection and a negative pressure release detection is given in advance to a data storage part, and a negative pressure combustion state detecting part judges the negative pressure detection. When the frame current detection value exceeds the upper threshold value, which is negative pressure detection data, over the entire section of the reference time, a negative pressure detection signal is generated, and negative pressure release detection is performed over the entire section of the negative pressure release detection determination reference time. 10. A negative pressure release detection signal is output when a lower threshold value, which is data, is exceeded in a lower direction.
A combustion device as described. 12. A time measuring means, wherein a judgment reference time for negative pressure detection and a negative pressure release detection is given in advance to a data storage section, and a negative pressure combustion state detecting section is provided with a judgment reference for the negative pressure detection. A configuration in which a negative pressure detection signal is output when the rising change amount of the frame current detection value within the time exceeds the rising change reference value, and a negative pressure release detection signal is output when the falling change amount exceeds the falling change reference value. The combustion device according to claim 6, 7 or 8, or 9 or 10. 13. A system delay time data in which a delay time from when a combustion heat amount change command is issued to when a flame rod current change corresponding to the change in combustion heat amount is taken into a frame current detection unit is given in advance. The negative pressure combustion state detection unit compares the detected flame current value taken at the present time with the negative pressure detection data and the negative pressure release detection data corresponding to the combustion heat amount at the time before the current time by the system delay time. Claims 8 to 12 are configured.
The combustion device according to any one of the above. 14. The combustion apparatus according to claim 13, further comprising a system delay time change setting unit that monitors the amount of combustion heat of the burner and changes the system delay time in a direction to increase as the amount of combustion heat increases. 15. A flame rod current take-in delay time from when the flame rod outputs a flame rod current to when the flame rod current is detected by the flame current detector is given in advance, and the negative pressure combustion state detector detects an increase in the flame rod current. When the reference value is given as the negative pressure detection data, and when the falling change reference value is given as the negative pressure release detection data, the time point earlier by the flame rod current take-in delay time than the current time is the reference point, and The frame current detection value taken in is compared with the frame current detection value of the frame rod current output from the frame rod within the judgment reference time before the reference point, and the current frame current detection value is within the judgment reference time. When a rising change exceeding the rising change reference value has occurred, a negative pressure detection signal is output, and the value falls below the falling change reference value. Combustion apparatus according to claim 12 configured to output a negative pressure releasing detection signal when the fall change has occurred. 16. A reverse signal for stopping the output of the signal on one side of the negative pressure detection signal and the negative pressure release detection signal until the cancellation time given in advance from the output of the signal when the signal on the one side is output. The combustion device according to any one of claims 5 to 15, further comprising an output cancel unit. 17. A change in the amount of combustion heat is monitored, and when the change in the amount of combustion heat exceeds a predetermined heat amount change set value, the operation of the negative pressure combustion state detection unit until the change in the amount of combustion heat falls within a predetermined allowable range. 17. A negative pressure condition detection interrupting unit for interrupting the operation is provided.
The combustion device according to any one of claims 1 to 3. 18. A negative pressure mode operation control unit that performs a predetermined negative pressure mode operation when a negative pressure detection signal is output from the negative pressure combustion state detection unit. 18. The combustion device according to any one of items 17. 19. The system according to claim 1, further comprising: a notifying unit that notifies the negative pressure combustion state while the negative pressure detection signal is being output from the negative pressure combustion state detection unit. A combustion device as described. 20. The negative pressure combustion status detecting section outputs a negative pressure detection signal in accordance with an excess of the flame current detection value exceeding the negative pressure detection data, and the notifying means takes in the information of the negative pressure detection signal and outputs a negative pressure. 20. The combustion device according to claim 19, wherein the degree of pressure combustion is notified separately. 21. The exhaust side of the combustion device includes CO in the exhaust gas.
A CO sensor for detecting the concentration is provided, and in the combustion operation after the burner ignition, a fan air volume control data switching control unit for switching the fan air volume control data to the air volume up side as the CO concentration detected by the CO sensor increases is provided. In addition to the basic function of switching the fan air volume control data to the air volume up side as the CO concentration increases, the fan air volume control data switching control unit also increases the upper threshold value at which the frame rod current is set in advance. A function to switch the fan air volume control data to the air volume down side when the frame rod current exceeds a preset lower threshold value to the lower side when the frame rod current exceeds a preset lower threshold value; Rod current rise change amount exceeds the rise change reference value within the preset reference time Function to switch the fan air volume control data to the air volume up side when the fan air volume control data changes to the air volume down side when the falling change amount of the frame rod current exceeds the descent change reference value within the preset reference time. One or more additional functions are provided for switching the fan air volume control data by a combination of the basic function and the additional function during a combustion operation in a low combustion capacity range equal to or less than a specified value in the combustion heat amount control range. Combustion device configured to be controlled.