JP2010164214A - Open type combustion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an open type combustion device for further improving safety against incomplete combustion. <P>SOLUTION: In this open type combustion device including a thermoelectric couple 13 disposed while being kept into contact with the flame formed by a burner, and outputting a higher value in accordance with increase of a temperature of the flame, an incomplete combustion gas sensor 17 detecting the concentration of a complete combustion gas, and a control means 4 detecting the incomplete combustion of the burner on the basis of detection information of the incomplete combustion gas sensor 17, a predetermined proper usable time of the thermoelectric couple 13 is longer than that of the incomplete combustion gas sensor 17, and a sensor replacement notifying means A is disposed to notify the necessity of replacement of the incomplete combustion gas sensor 17 in a case when the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor 17 is outside of an allowable range set on the basis of the concentration corresponding to the output of the thermoelectric couple, of the incomplete combustion gas determined from the output of the thermoelectric couple 13, when the output of the thermoelectric couple 13 becomes a predetermined set value for discrimination or less. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

The present invention comprises a burner for burning supplied fuel;
A thermocouple equipped in contact with the flame formed by the burner;
An incomplete combustion gas sensor for detecting the concentration of incomplete combustion gas;
The present invention relates to an open-type combustion apparatus provided with control means for detecting incomplete combustion of the burner based on detection information of the incomplete combustion gas sensor.

Such an open-type combustion apparatus is operated in a state where combustion gas of the burner is released into the room, and specific examples include a gas fan heater and a gas stove.
Then, the incomplete combustion of the burner is detected based on the detection information of the incomplete combustion gas sensor for detecting the concentration of the incomplete combustion gas. When the incomplete combustion is detected, the burner is stopped and, for example, an alarm means is provided. Safety measures against incomplete combustion are taken by configuring so as to execute processing such as operation (see, for example, Patent Document 1).

JP 2008-14551 A

  As the use period of the incomplete combustion gas sensor, a proper useable period is set in advance, and when the proper useable period elapses, the incomplete combustion gas sensor is replaced. However, even if the proper usable period has not elapsed, the performance of the incomplete combustion gas sensor may be deteriorated due to factors such as quality variations. For this reason, although the incomplete combustion gas sensor cannot detect the incomplete combustion properly, the incomplete combustion gas sensor may continue to be used. There was room for improvement in further improvement.

  This invention is made | formed in view of this situation, The objective is to provide the open type combustion apparatus which can improve further the safety | security with respect to incomplete combustion.

An open combustion apparatus of the present invention comprises a burner for burning supplied fuel,
A thermocouple that is equipped in contact with the flame formed by the burner and outputs a higher value as the temperature of the flame is higher,
An incomplete combustion gas sensor for detecting the concentration of incomplete combustion gas;
An open type combustion apparatus provided with a control means for detecting incomplete combustion of the burner based on detection information of the incomplete combustion gas sensor,
The first characteristic configuration is a configuration in which a preset proper usable period is longer in the thermocouple than in the incomplete combustion gas sensor,
The incomplete combustion gas in which the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor is obtained from the output of the thermocouple when the output of the thermocouple becomes equal to or lower than a preset determination value. When the concentration is outside the allowable range set based on the thermocouple output corresponding concentration, sensor replacement notification means for notifying that the incomplete combustion gas sensor needs to be replaced is provided.

That is, if the performance of both the incomplete combustion gas sensor and the thermocouple has not deteriorated, the incomplete combustion gas obtained from the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor and the output of the thermocouple The concentration corresponding to the thermocouple output is the same value. Therefore, in this case, the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor is within the allowable range set based on the thermocouple output corresponding concentration of the incomplete combustion gas obtained from the thermocouple output. Become.
The proper usable period is longer for thermocouples than for incomplete combustion gas sensors, so even if the performance of the incomplete combustion gas sensor deteriorates, the concentration corresponding to the thermocouple output of the incomplete combustion gas is determined based on the thermocouple output. It can be determined with sufficient accuracy. Therefore, when only the performance of the incomplete combustion gas sensor is degraded, the incomplete combustion gas concentration detected by the incomplete combustion gas sensor can be calculated from the thermocouple output. It becomes out of the allowable range set based on the concentration, and the sensor replacement notification means notifies that the incomplete combustion gas sensor needs to be replaced. Here, regarding the proper usable period, the fact that the thermocouple is longer than the incomplete combustion gas sensor means that the use period is selected in the above relationship.

Therefore, the set value for discrimination is set to the output value of the thermocouple corresponding to the concentration of the incomplete combustion gas that is higher than the lower limit value of the concentration of the incomplete combustion gas that can be detected by the incomplete combustion gas sensor whose performance has not deteriorated. To do.
When the thermocouple output (corresponding to the concentration of the incomplete combustion gas) falls below the set value for determination, the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor becomes the concentration corresponding to the thermocouple output. By determining whether or not the incomplete combustion gas sensor needs to be replaced based on whether or not it is within an allowable range set on the basis of this, it is possible to appropriately determine whether or not the incomplete combustion gas sensor needs to be replaced.
Therefore, it is possible to accurately determine that the replacement of the incomplete combustion gas sensor is necessary due to the performance degradation, and to notify that the replacement of the incomplete combustion gas sensor is necessary. An open-type combustion apparatus that can be further improved can be provided.

In addition to the first feature configuration, the second feature configuration is
The allowable range on the low concentration side on the low concentration side with respect to the thermocouple output corresponding concentration is set narrower than the allowable range on the high concentration side on the high concentration side with respect to the thermocouple output corresponding concentration. is there.

In other words, the narrower the permissible range, the easier it is to determine that the incomplete combustion gas sensor needs to be replaced. Therefore, it is determined that the replacement is necessary even though the performance has not deteriorated to the extent necessary. As a result, it may be unnecessarily notified that the incomplete combustion gas sensor needs to be replaced.
On the other hand, although the wider the allowable range, the unnecessary notification that the incomplete combustion gas sensor needs to be replaced can be avoided, but the performance is reduced to the extent that it is preferable to replace it. Therefore, it may be determined that the replacement is unnecessary, and the notification that the replacement of the incomplete combustion gas sensor is necessary may be delayed.
And, if the performance of the incomplete combustion gas sensor deteriorates in a state where the concentration of the detected incomplete combustion gas is higher than the actual concentration, it is easy to detect incomplete combustion, so there is a problem in terms of safety. On the contrary, if the performance of the incomplete combustion gas sensor deteriorates in a state where the concentration of the detected incomplete combustion gas is lower than the actual concentration, it is difficult to detect incomplete combustion. May cause problems.
Therefore, even if the allowable range is set based on the thermocouple output corresponding concentration, by setting the allowable range on the low concentration side narrower than the allowable range on the high concentration side, the incomplete combustion gas sensor While suppressing unnecessary notification that the replacement is necessary, it is possible to accurately notify the safety so as not to be impaired.
Accordingly, it is possible to further improve the safety against incomplete combustion while suppressing unnecessary replacement of the incomplete combustion gas sensor.

In addition to the first or second feature configuration, the third feature configuration is
The determination set value can be set to an output of the thermocouple corresponding to a concentration in a predetermined range equal to or lower than an incomplete combustion gas concentration for detecting incomplete combustion of the burner,
The allowable range is set narrower as the set value for determination is set to the output of the thermocouple having a higher concentration of incomplete combustion gas.

That is, the higher the set value for determination, the easier the output of the thermocouple becomes below the set value for determination, and the more frequently the process for determining whether or not the incomplete combustion gas sensor needs to be replaced is performed. By configuring so that the set value for determination can be set to the output of a thermocouple corresponding to a predetermined range of concentrations below the incomplete combustion gas concentration, for example, according to the necessity of determining whether the incomplete combustion gas sensor needs to be replaced Thus, the setting value for determination can be changed and set.
For example, since the performance of the incomplete combustion gas sensor decreases as the usage time of the incomplete combustion gas sensor becomes longer, the set value for determination is set higher as the usage time of the incomplete combustion gas sensor becomes longer. It is preferable to increase the frequency of determining whether or not replacement is necessary.

The detection accuracy of the incomplete combustion gas concentration by the incomplete combustion gas sensor increases as the concentration of the incomplete combustion gas in the air to be detected increases.
Therefore, even if the discriminating set value can be set within a predetermined range, the allowable range becomes narrower as the discriminating set value is set to the output of a thermocouple having a high concentration of incomplete combustion gas. By doing so, it is possible to accurately notify that safety is not impaired while suppressing unnecessary notification that replacement of an incomplete combustion gas sensor is unnecessary.
Accordingly, it is possible to accurately notify that the replacement of the incomplete combustion gas sensor is necessary due to the performance degradation while the setting value for determination can be changed and set.

In addition to the first or second feature configuration, the fourth feature configuration is
The determination set value is set to an output of the thermocouple corresponding to an incomplete combustion gas concentration for detecting incomplete combustion of the burner.

That is, since the detection accuracy of the incomplete combustion gas sensor increases as the concentration of the incomplete combustion gas in the air to be detected increases, the determination setting value is set to the incomplete combustion gas concentration for detecting the incomplete combustion of the burner. By setting the output of the thermocouple corresponding to the above, the allowable range is set as narrow as possible, and safety is impaired while minimizing unnecessary notification that the incomplete combustion gas sensor needs to be replaced. It is possible to make it possible to accurately notify so that it does not occur.
Accordingly, it is possible to further improve the safety against incomplete combustion while suppressing unnecessary replacement of the incomplete combustion gas sensor as much as possible.

In addition to any one of the first to fourth feature configurations described above, the fifth feature configuration is
The incomplete combustion gas sensor is provided in a detachable state,
The sensor replacement notification means is configured to notify that it is necessary to replace the incomplete combustion gas sensor when the time when the proper usable period of the incomplete combustion gas sensor expires is approaching.

  That is, a process for determining whether or not the incomplete combustion gas sensor needs to be replaced depending on whether or not the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor is within an allowable range set based on the thermocouple output correspondence concentration, that is, Based on the actual detection information of the incomplete combustion gas sensor, the need for replacement is determined by the instability of combustion of the burner so that incomplete combustion gas is generated and the thermocouple output is set for discrimination. It is not executed unless it falls below the value.

Therefore, the sensor replacement notification means is configured to notify that the replacement of the incomplete combustion gas sensor is necessary when the appropriate usable period of the incomplete combustion gas sensor expires, so that the actual state of the incomplete combustion gas sensor is The proper usable period of the incomplete combustion gas sensor expires until the next determination process is performed based on the detected information or even if it is determined that the replacement process is not necessary. As time approaches, the sensor replacement notification means will notify that the incomplete combustion gas sensor needs to be replaced.
Incidentally, the proper usable period is set to a period during which the concentration of the incomplete combustion gas can be detected so that the incomplete combustion can be accurately detected, and the incomplete combustion gas sensor can be used appropriately.
Since the incomplete combustion gas sensor is provided in a detachable state, when the sensor replacement notification means informs that the incomplete combustion gas sensor needs to be replaced, the incomplete combustion gas sensor is easily replaced with a new one. Can be exchanged.
Therefore, since the incomplete combustion gas sensor can be replaced accurately before the performance deteriorates to a certain extent that the incomplete combustion cannot be properly detected, the safety against incomplete combustion can be further improved. In addition, the incomplete combustion gas sensor can be easily replaced.

In addition to the fifth feature configuration, the sixth feature configuration is
The sensor replacement notifying means is configured to determine that the time when the appropriate usable period expires is approaching when the accumulated combustion time obtained by integrating the combustion time during which the burner burns reaches a preset notification setting time. There is in point.

That is, when the driving power is supplied to the incomplete combustion gas sensor, the incomplete combustion gas sensor becomes in a detectable state where the concentration of the incomplete combustion gas can be detected. The decrease in performance is faster than when the detection is not performed.
In general, the incomplete combustion gas sensor is brought into a detectable state while the burner is being burned.
Therefore, the sensor replacement notification means is configured to determine that the time when the proper usable period expires has approached when the accumulated combustion time obtained by integrating the combustion time in which the burner burns reaches a preset notification time. Thus, it is possible to accurately notify that the time when the appropriate usable period expires is suppressed from becoming too early.
Therefore, it is possible to replace the incomplete combustion gas sensor accurately before the performance deteriorates to a certain extent while it may be impossible to properly detect incomplete combustion while suppressing unnecessary replacement. .

In addition to any one of the first to sixth feature configurations described above, the seventh feature configuration is
Air outside the casing sucked through an intake port provided in a casing that houses the burner is supplied to the burner as combustion air, and combustion gas of the burner is discharged from a blowout port provided in the casing to the outside of the casing. Blowing means that ventilate so as to blow out is provided,
The incomplete combustion gas sensor is provided at or near the intake port so as to detect the concentration of incomplete combustion gas in the air sucked through the intake port.

That is, when a specific example of the open-type combustion device is a fan heater using gas fuel or liquid fuel as fuel, the air outside the casing sucked through the intake port is supplied to the burner as combustion air by the blowing means, and The space to be heated is heated by blowing the combustion gas of the burner out of the casing from the outlet provided in the casing.
Since the incomplete combustion gas sensor is provided in the intake port or in the vicinity of the intake port so as to detect the concentration of the incomplete combustion gas in the air sucked through the intake port, the incomplete combustion gas sensor is included in the air in the heating target space. It becomes possible to detect incomplete combustion based on the detection information of the complete combustion gas concentration, and it is possible to accurately detect that safety is impaired by incomplete combustion.
Accordingly, it is possible to provide a fan heater that can further improve the safety against incomplete combustion.

It is a vertical side view which shows schematic structure of the open type combustion apparatus which concerns on embodiment. It is a block diagram of the open type combustion apparatus which concerns on embodiment. It is a figure which shows the relationship between the electromotive force of a thermocouple, and the carbon monoxide gas concentration detected by a CO sensor. It is a figure which shows the flowchart of control operation of the open type combustion apparatus which concerns on 1st Embodiment. It is a figure which shows the flowchart of control operation of the open type combustion apparatus which concerns on 2nd Embodiment.

Hereinafter, an embodiment in the case where the present invention is applied to a gas fan heater as an example of an open combustion apparatus will be described with reference to the drawings.
[First Embodiment]
Hereinafter, the first embodiment will be described.
As shown in FIGS. 1 and 2, the gas fan heater includes a burner 1 for burning supplied gas fuel, a thermocouple 13 equipped in contact with a flame formed by the burner 1, and A CO sensor 17 as an incomplete combustion gas sensor for detecting incomplete combustion gas such as carbon monoxide gas generated when the burner 1 is incompletely combusted, and a control unit 4 as control means for controlling the operation of the gas fan heater. Etc. are provided.

  The gas fan heater further ignites the fuel intermittent means V and burner 1 which can be switched between a fuel supply state in which gas fuel is supplied to the burner 1 and a fuel supply stop state in which supply of gas fuel to the burner 1 is stopped. The igniter 2 that performs the operation, the blower 5 that supplies the combustion air to the burner 1, the constant voltage circuit 6 that supplies the driving power for the gas fan heater, and the operation unit 7 that instructs the control unit 4 to give various control commands. Is also provided.

As shown in FIG. 1, the burner 1 is housed in a casing 10 having an intake port 8 on the upper side of the back surface and an outlet port 9 on the lower side of the front surface.
In the casing 10, a part of the air outside the casing sucked through the intake port 8 is guided to the burner 1 as combustion air, and the remaining portion is guided to the outlet port 9 in a state mixed with the combustion gas of the burner 1. Thus, an internal air passage 11 is formed. An air filter 12 is provided at the intake port 8.
The blower 5 is in a state in which the air suction is applied to the air inlet 8 and the discharge part faces the air outlet 9, that is, a part of the air outside the casing sucked through the air inlet 8 is used as the combustion air. 1, and the remaining portion is mixed with the combustion gas of the burner 1, and is provided in the middle of the internal air passage 11 so as to blow air from the outlet 9 to the outside of the casing.
And by the ventilation effect | action of the air blower 5, the combustion gas of the burner 1 is mixed with the air of the heating object space suck | inhaled through the inlet port 8, a warm air is produced | generated, and the warm air blows off from the blower outlet 9 to the heating object space. Thus, the space to be heated is heated.

As shown in FIG. 1, the thermocouple 13 is provided above the flame outlet (not shown) of the burner 1 so that the flame formed by the burner 1 is in contact with the igniter 2. It is provided above.
As shown in FIGS. 1 and 2, the fuel supply passage 14 for supplying gas fuel to the burner 1 has an electromagnetic on-off valve 15 for opening and closing the fuel supply passage 14 and the fuel supply amount to the burner 1. An electromagnetic proportional valve 16 to be adjusted is provided, and the on-off valve 15 and the proportional valve 16 constitute a fuel intermittent means V.
The fuel supply path 14 is connected to, for example, a city gas pipe (not shown) to which city gas (13A or the like, gas mainly composed of methane gas (CH ₄ )) is supplied. It is supplied to the burner 1.

  The CO sensor 17 (corresponding to an incomplete combustion gas sensor) is provided at the intake port 8 of the casing 10 so as to detect the concentration of carbon monoxide gas in the air sucked through the intake port 8.

  The constant voltage circuit 6 is configured to step down and rectify and smooth a commercial AC power supply to obtain a predetermined DC voltage. When the plug 19 of the power cord 18 for supplying device driving power to the gas fan heater is inserted into a power outlet (not shown) to which commercial power is supplied, the constant voltage circuit 6 supplies the control unit 4 with power. Driving power for driving it is configured to be supplied.

Since the CO sensor 17 is well known, a detailed description and illustration thereof will be omitted and will be briefly described.
In this embodiment, for example, a semiconductor sensor is used as the CO sensor 17, and the semiconductor sensor includes a sensor element made of a metal oxide semiconductor such as tin oxide. The sensor element has a characteristic that the resistance value changes in accordance with the concentration when contacting the carbon monoxide gas, and detects the concentration of the carbon monoxide gas based on the resistance value of the sensor element. It is configured.
The CO sensor 17 includes an electric heater (not shown) for heating the sensor element, a heating control unit (not shown) for controlling the heating operation of the electric heater, and the like. The CO sensor 17 includes a constant voltage circuit 6. As the sensor driving power is supplied from the electric heater, heating of the sensor element is started by the electric heater, and thereafter, the heating operation of the electric heater is controlled so that the temperature of the sensor element becomes a predetermined heating target temperature. It is configured as follows.
And if it heats to the heating target temperature set with respect to the sensor element of the CO sensor 17, the CO sensor 17 will be in the detection possible state which can detect the density | concentration of carbon monoxide gas.

The CO sensor 17 is capable of detecting the carbon monoxide gas concentration with sufficient accuracy so that incomplete combustion can be properly detected, and has an appropriate usable period in which it can be used properly. In the first embodiment, the proper usable period is set to 12000 hours, for example.
The CO sensor 17 is provided so as to be detachable from the open-type combustion device so that the CO sensor 17 can be easily replaced.
In other words, the performance of the sensor element of the CO sensor 17 decreases as time elapses when the sensor element is heated by the electric heater to be in a detectable state.
Therefore, the open-type combustion apparatus is configured such that the sensor element and the electric heater are integrally assembled to form a sensor element unit, and the sensor element unit is detachable by insertion into and removal from a socket provided in the open-type combustion apparatus. The CO sensor 17 can be easily replaced.

The temperature of the flame formed by the burner 1 decreases as the concentration of oxygen in the combustion air supplied by the blower 5 decreases, in other words, as the concentration of carbon monoxide gas in the combustion air increases. The output of the thermocouple 13 provided in contact with the flame, that is, the electromotive force, becomes smaller as the temperature of the flame in the portion measured by the thermocouple 13 becomes lower.
Then, the controller 4 detects whether or not the burner 1 has ignited when igniting the burner 1 based on the electromotive force of the thermocouple 13, and after the ignition of the burner 1, the burner 1 performs incomplete combustion. It is configured to detect whether or not to wake up.

In FIG. 3, the burner 1 is burned in a room where the incomplete combustion of the burner 1 can be experimentally caused, and the electromotive force (voltage) of the thermocouple 13 from the ignition time of the burner 1 and the CO sensor 17. The result of having measured change with time progress of each carbon monoxide concentration detected is shown.
It can be seen that the carbon monoxide concentration detected by the CO sensor 17 increases with time after the ignition of the burner 1, and the electromotive force of the thermocouple 13 decreases accordingly.

Then, the burner 1 is burned with different carbon monoxide concentrations in the combustion air in advance, the carbon monoxide concentration in the combustion air is detected by the CO sensor 17, and the electromotive force of the thermocouple 13 is changed. By measuring, the relationship between the detected carbon monoxide gas concentration of the CO sensor 17 and the electromotive force of the thermocouple 13 is obtained, and based on the relationship, the carbon monoxide gas in the air is derived from the electromotive force of the thermocouple 13. The concentration can be determined.
For example, when the relationship between the electromotive force of the thermocouple 13 and the detected carbon monoxide gas concentration of the CO sensor 17 is as shown in FIG. 3, the electromotive force (voltage) of the thermocouple 13 is 15 mV based on the relationship. In this case, the concentration of carbon monoxide gas in the air is determined as 20 ppm.

As shown in FIG. 2, the operation unit 7 includes an operation switch 20 for instructing start and stop of operation of the gas fan heater, a replacement notification lamp 21 that is turned on when the CO sensor 17 needs to be replaced, and incomplete combustion. An abnormality notification lamp 22 that is turned on when the temperature is detected, a temperature setting unit 23 that sets the heating target temperature, a display unit (not shown) that displays various information such as the heating target temperature and the room temperature, and the like are provided.
The operation switch 20 is configured so that an operation start and an operation stop are alternately commanded every time the push operation is repeated.

Hereinafter, the control operation of the control unit 4 will be described.
The control unit 4 sets in advance the incomplete combustion detection concentration set to the carbon monoxide gas concentration for detecting incomplete combustion, and the electromotive force of the thermocouple 13 corresponding to the incomplete combustion detection concentration. The incomplete combustion detection electromotive force, the determination set value set in the electromotive force of the thermocouple 13 for executing the process of determining whether or not the CO sensor 17 needs to be replaced, and the determination The allowable range for determining whether or not the CO sensor 17 needs to be replaced is stored based on the concentration corresponding to the thermocouple output of the incomplete combustion gas obtained from the set value for use.
In this embodiment, the concentration for incomplete combustion detection is set to 30 ppm, for example.

The control unit 4 starts the control operation when the supply of driving power is started as the plug 19 of the power cord 18 is inserted into the power outlet.
Then, when the operation start is commanded by the operation switch 20, the control unit 4 controls the operation of the heating control unit so as to supply power for driving the sensor so that the CO sensor 17 can be detected. The sensor 17 is activated and an ignition process for igniting the burner 1 is executed. After that, when an operation stop command is issued by the operation switch 20, a fire extinguishing process for extinguishing the burner 1 is executed.

  In the ignition process, the control unit 4 operates the blower 5 and, after the blower 5 is activated, activates the igniter 2 and opens the on-off valve 15 and the proportional valve 16 when the pre-purge set time has elapsed. When the ignition of the burner 1 is detected by the electromotive force 13, a process of stopping the operation of the igniter 2 (corresponding to switching to the fuel supply state) is executed, and in the fire extinguishing process, the on-off valve 15 and the proportional valve 16 are closed. (This corresponds to switching to the fuel supply stop state), and after the valves are closed, a process for stopping the blower 5 is executed when the post-purge setting time has elapsed. Incidentally, the pre-purge setting time is set to a time in the range of 4 to 7 seconds, for example, and the post-purge setting time is set to a time in the range of 100 to 160 seconds, for example.

In the present invention, even if the CO sensor 17 is not in the proper usable period, the control unit 4 starts the ignition process in order to detect the performance deterioration of the CO sensor 17 and notify the user of the fact. The concentration of the incomplete combustion gas detected by the CO sensor 17 when the electromotive force E of the thermocouple 13 becomes equal to or less than a preset determination value Es between the time point and the end of the fire extinguishing process. When D is outside the allowable range set based on the thermocouple output corresponding concentration Ds of the incomplete combustion gas obtained from the electromotive force of the thermocouple 13, the replacement notification lamp 21 is turned on.
That is, when the electromotive force E of the thermocouple 13 becomes equal to or less than the set value for determination Es, the concentration D of incomplete combustion gas detected by the CO sensor 17 is set based on the thermocouple output corresponding concentration Ds. A sensor replacement notification means A for notifying that the replacement of the CO sensor 17 is necessary when it is outside the allowable range includes the control unit 4 and the replacement notification lamp 21.

Hereinafter, the setting of the allowable range (the range sandwiched by the one-dot chain line in FIG. 3) will be described based on FIG.
In the first embodiment, regarding the allowable range, the allowable range on the low concentration side where the concentration is lower than the concentration corresponding to the thermocouple output is the allowable range on the high concentration side where the concentration is higher than the concentration corresponding to the thermocouple output. It is set narrower than the range.
The set value for determination is the electromotive force of the thermocouple 13 corresponding to a predetermined range of concentration below the incomplete combustion gas concentration for detecting the incomplete combustion of the burner 1 (that is, the incomplete combustion detection concentration). The allowable range is set narrower as the set value for determination is set to the electromotive force of the thermocouple 13 having a higher concentration of incomplete combustion gas.

The carbon monoxide gas concentration range in which the set value for determination Es can be set is set, for example, from 20 ppm to a range of 30 ppm that is an incomplete combustion gas concentration for detecting incomplete combustion.
Subtract from the upper limit value setting addition value Ka for setting the upper limit value Lmax of the allowable range by adding to the thermocouple output corresponding concentration Ds corresponding to the determination setting value Es, and the thermocouple output corresponding concentration Ds. If the lower limit value setting subtraction value Kd for setting the lower limit value Lmin of the allowable range is equal to the thermocouple output corresponding concentration Ds, the upper limit value setting addition value Ka is larger under the condition that It is set in a state where it decreases as the output corresponding density Ds increases.
Then, the upper limit value Lmax and the lower limit value Lmin of the allowable range are set by the following formula using the lower limit value setting subtraction value Kd and the upper limit value setting addition value Ka.

Lmin = Ds−Kd
Lmax = Ds + Ka

For example, the upper limit setting addition value Ka is in the range of 20 ppm when the thermocouple output corresponding concentration Ds is 20 ppm to 8 ppm when the thermocouple output corresponding concentration Ds is 30 ppm, and the lower limit setting subtraction value Kd is In the range from 10 ppm when the thermocouple output corresponding concentration Ds is 20 ppm to 5 ppm when the thermocouple output corresponding concentration Ds is 30 ppm, the thermocouple output corresponding concentration Ds is set so as to decrease as the thermocouple output corresponding concentration Ds increases.
In the first embodiment, for example, as shown in FIG. 3A, the setting value for determination Es is set to 15 mV, and the thermocouple output corresponding concentration Ds corresponding to the electromotive force of 15 mV is 20 ppm. The upper limit value Lmax of the allowable range is set to 40 ppm, and the lower limit value Lmin of the allowable range is set to 10 ppm.

In addition, the control unit 4 performs a thermocouple incomplete combustion detection process for detecting whether or not incomplete combustion has occurred based on the electromotive force of the thermocouple 13 from the start of the ignition process to the end of the fire extinguishing process. And the sensor utilization incomplete combustion detection process which detects the presence or absence of generation | occurrence | production of incomplete combustion based on the detection information of CO sensor 17 is performed.
And the control part 4 is comprised so that a fire extinguishing process may be performed if the electromotive force of the thermocouple 13 becomes below the electromotive force for imperfect combustion detection in the thermocouple utilization imperfect combustion detection process, and imperfect combustion is detected. Has been.
Further, in the sensor-based incomplete combustion detection process, the control unit 4 performs the fire extinguishing process when the concentration of the incomplete combustion gas detected by the CO sensor 17 exceeds the concentration for incomplete combustion detection and detects incomplete combustion. Is configured to run.

Further, the control unit 4 integrates the time from the start of the ignition process to the end of the fire extinguishing process, that is, the combustion time of the burner 1, and when the accumulated combustion time reaches a preset notification time. The replacement notification lamp 21 is lit.
In the first embodiment, the notification setting time is set to a time (for example, 10,000 hours) that is slightly shorter than the time corresponding to 12000 hours of the proper usable period.
That is, the sensor replacement notification means A is configured to notify that the replacement of the CO sensor 17 is necessary when the time when the proper usable period of the CO sensor 17 expires is approaching.
Further, the sensor replacement notification means A determines that the time when the proper usable period expires has approached when the accumulated combustion time obtained by integrating the combustion time during which the burner 1 burns reaches a preset notification time. It will be configured.

Next, a series of control operations by the control unit 4 will be described based on the flowchart shown in FIG.
When the driving power is supplied as the plug 19 of the power cord 18 is inserted into the power outlet, the control unit 4 starts the control operation.
Then, when the operation start is instructed by the operation switch 20, the control unit 4 executes a sensor activation process to make the CO sensor 17 in a detectable state, and subsequently executes an ignition process for igniting the burner 1 ( Step # 1-3).

After the ignition process is executed, the control unit 4 performs a combustion time integration process for integrating the combustion time of the burner 1 until an operation stop command is issued by the operation switch 20, and whether the integrated combustion time reaches the notification set time. The combustion time discriminating process for discriminating whether the burner 1 burns by adjusting the opening of the proportional valve 16 so that the detected temperature of the room temperature sensor (not shown) for detecting the temperature of the heating target space becomes the heating target temperature. Combustion amount adjustment control to be adjusted, thermocouple use incomplete combustion detection process, thermocouple output discrimination process for judging whether electromotive force E of thermocouple 13 is equal to or less than set value Es for discrimination, sensor incomplete combustion detection using sensor When the operation switch 20 is instructed to stop the operation without detecting the incomplete combustion in either the thermocouple-based incomplete combustion detection process or the sensor-based incomplete combustion detection process, the fire is extinguished. Run the management, as well as, after executing the sensor stop process for controlling the operation of the heating control unit to stop the supply of the sensor drive power to the CO sensor 17, the process returns (step # 4-12).
Incidentally, the control unit 4 executes the combustion time integration process and the combustion amount adjustment control every set period for adjusting the combustion amount, as well as the thermocouple output determination process, the thermocouple use incomplete combustion detection process, and the sensor use incomplete. The combustion detection process is executed every set period for detecting an abnormality.

  When determining that the accumulated combustion time has reached the notification set time in the combustion time integration process of step # 5, the control unit 4 lights the replacement notification lamp 21 in step # 13 and proceeds to step # 6.

  When detecting incomplete combustion in the thermocouple utilizing incomplete combustion detection process in step # 7, the control unit 4 executes a fire extinguishing process, turns on the abnormality notification lamp 22, and issues a reset command by a reset switch (not shown). The system waits until the command is issued. When the reset command is issued, the abnormality notification lamp 22 is turned off, the sensor stop process is executed (steps # 14 to 17, 12), and the process returns.

When determining that the electromotive force E of the thermocouple 13 is equal to or less than the determination set value Es in the thermocouple output determination process in step # 8, the control unit 4 detects the error detected by the CO sensor 17 in step # 18. It is determined whether or not the complete combustion gas concentration D is within the allowable range set based on the thermocouple output corresponding concentration Ds. If the complete combustion gas concentration D is within the allowable range, the process proceeds to step # 9. After the replacement notification lamp 21 is lit in step # 19, the process proceeds to step # 9.
In addition, when the incomplete combustion is detected in the sensor-based incomplete combustion detection process in step # 9, the control unit 4 also performs steps # 14 to 17, 12 as in the case of detecting incomplete combustion in step # 7. After executing the process, return.
That is, when incomplete combustion is detected and the abnormality notification lamp 22 is turned on, the operation start command from the operation switch 20 is not accepted until the reset switch is pressed and a return command is issued.
Incidentally, when the abnormality notification lamp 22 is turned on, the user or the like presses the reset switch after confirming safety.

[Second Embodiment]
The second embodiment will be described below.
The second embodiment describes another embodiment of the setting example of the setting value for determination, and the control operation of the control unit 4 differs from that of the first embodiment as the setting value for determination is different. However, since the overall configuration of the gas fan heater is the same as that of the first embodiment, the control operation of the control unit 4 will be mainly described.

In the second embodiment, the set value for determination is set to the electromotive force of the thermocouple 13 corresponding to the incomplete combustion gas concentration for detecting the incomplete combustion of the burner 1.
For example, when the concentration of incomplete combustion gas for detecting incomplete combustion is 30 ppm as in the first embodiment, the set value for determination is the start of the thermocouple 13 corresponding to the concentration of incomplete combustion gas of 30 ppm. The electric power, that is, the incomplete combustion detection electromotive force is set.
Further, the allowable range for determining whether or not the CO sensor 17 needs to be replaced uses the lower limit value setting subtraction value Kd and the upper limit value setting addition value Ka, as in the first embodiment. Is set.

  In the same manner as in the first embodiment, the control unit 4 determines that the electromotive force E of the thermocouple 13 is set in advance from the start of the ignition process to the end of the fire extinguishing process. When the following occurs, the concentration D of the incomplete combustion gas detected by the CO sensor 17 is set based on the thermocouple output corresponding concentration Ds of the incomplete combustion gas obtained from the electromotive force of the thermocouple 13 When it is out of the range, the replacement notification lamp 21 is lit.

Next, a series of control operations by the control unit 4 will be described based on the flowchart shown in FIG.
In FIG. 5, the control operations of steps # 31 to 33 are the same as the control operations of steps # 1 to # 3 of FIG. 4 described in the first embodiment, and a description thereof will be omitted.
After executing the ignition process, the control unit 4 performs the combustion time integration process, the combustion time determination process, the combustion amount adjustment control, the thermocouple use incomplete combustion detection process, the sensor use failure until the operation stop is instructed by the operation switch 20. When the complete combustion detection process is executed, and the operation switch 20 is instructed to stop the operation without detecting the incomplete combustion in either the thermocouple-based incomplete combustion detection process or the sensor-based incomplete combustion detection process, the fire extinguishing process And the sensor stop process is executed, and then the process returns (steps # 34 to 41).

  When the control unit 4 determines in the combustion time integration process of step # 35 that the integrated combustion time has reached the notification set time, the replacement notification lamp 21 is turned on in step # 42 and the process proceeds to step # 36.

In the thermocouple-use incomplete combustion detection process, when the electromotive force of the thermocouple 13 falls below the incomplete combustion detection electromotive force and the incomplete combustion is detected, the electromotive force E of the thermocouple 13 is set to the determination set value Es. It corresponds to the following.
Therefore, when the controller 4 detects incomplete combustion in the thermocouple-use incomplete combustion detection process in step # 37, the concentration D of the incomplete combustion gas detected by the CO sensor 17 is determined in step # 43 as a thermocouple. It is determined whether or not it is within the allowable range set based on the output corresponding density Ds. If within the allowable range, the fire extinguishing process is executed, the abnormality notification lamp 22 is turned on, and a reset command is issued by the reset switch When the reset command is issued, the abnormality notification lamp 22 is turned off, the sensor stop process is executed (steps # 44 to 47, 41), and the process returns.
If the controller 4 determines in step # 43 that the incomplete combustion gas concentration D detected by the CO sensor 17 is outside the allowable range, the controller 4 turns on the replacement notification lamp 21 in step # 48. After executing steps # 44 to 47, 41, the process returns.
The control unit 4 also returns after performing the processes of steps # 44 to 47.41 even when the incomplete combustion is detected in the sensor-based incomplete combustion detection process of step # 38.

[Another embodiment]
Next, another embodiment will be described.
(A) The specific set value for the discrimination set value is not limited to the values exemplified in the first and second embodiments, and is a value for detecting incomplete combustion of the burner 1. The electromotive force of the thermocouple 13 corresponding to various concentrations within a predetermined range (for example, 20 to 30 ppm) below the complete combustion gas concentration can be set.
In the first and second embodiments described above, the set value for determination is set to one value, but it is within a predetermined range below the incomplete combustion gas concentration for detecting the incomplete combustion of the burner 1. It may be configured to change and set with.
For example, since the performance of the incomplete combustion gas sensor 17 decreases as the usage time of the incomplete combustion gas sensor 17 becomes longer, the setting value for determination is set higher as the usage time of the incomplete combustion gas sensor 17 becomes longer. The frequency of determining whether or not the incomplete combustion gas sensor 17 needs to be replaced may be increased as the use time of the complete combustion gas sensor 17 becomes longer.
In this case, the frequency of determining whether or not the incomplete combustion gas sensor 17 needs to be replaced increases as the performance of the incomplete combustion gas sensor 17 progresses. Can be notified.

(B) The setting method of the allowable range for determining whether or not the CO sensor 17 needs to be replaced is not limited to the setting method exemplified in the above embodiment.
For example, in the above embodiment, the allowable range on the low concentration side on the low concentration side with respect to the thermocouple output corresponding concentration is higher than the allowable range on the high concentration side on the high concentration side with respect to the thermocouple output corresponding concentration. Although set narrowly, the allowable range on the low density side and the allowable range on the high density side may be set to the same width.
Further, by multiplying the thermocouple output corresponding concentration Ds corresponding to the discrimination setting value Es, by multiplying the upper limit value setting coefficient Ra for setting the upper limit Lmax of the allowable range and the thermocouple output corresponding concentration Ds. The lower limit value setting coefficient Rd for setting the lower limit value Lmin of the allowable range decreases as the thermocouple output corresponding concentration Ds increases under the condition that the upper limit value setting coefficient Ra is greater than 1, and the lower limit value setting coefficient Rd. Is set so as to increase as the thermocouple output-corresponding concentration Ds increases under a condition smaller than 1, and the upper limit value Lmax and lower limit of the allowable range are set using the upper limit value setting coefficient Ra and the lower limit value setting coefficient Rd. The value Lmin may be set by the following mathematical formula.

Lmin = Ds × Rd
Lmax = Ds × Ra

For example, the upper limit value setting coefficient Ra is in a range from 2 when the thermocouple output corresponding concentration Ds is 20 ppm to 1.2 when the thermocouple output corresponding concentration Ds is 30 ppm, and the thermocouple output corresponding concentration Ds increases. The lower limit value setting coefficient Rd is set within a range from 0.5 when the thermocouple output corresponding concentration Ds is 20 ppm to 0.9 when the thermocouple output corresponding concentration Ds is 30 ppm. It can be set to increase as the output corresponding density Ds increases.
Further, by setting each of the upper limit value setting coefficient Ra and the lower limit value setting coefficient Rd under the condition of Ra-1> 1-Rd, the lower concentration side where the concentration is lower than the thermocouple output corresponding concentration Ds. Is set narrower than the allowable range on the high concentration side on the higher concentration side with respect to the thermocouple output corresponding concentration Ds.

(C) The specific configuration of the sensor replacement notification means A that notifies that the replacement of the incomplete combustion gas sensor 17 is necessary is limited to the case where the replacement notification lamp 21 as illustrated in the above embodiment is provided. It is not a thing. For example, a speaker that outputs a message that the incomplete combustion gas sensor 17 needs to be replaced by voice or a display device that displays and outputs such a message may be provided. Moreover, you may comprise including any two or all of the replacement | exchange notification lamp 21, the speaker which outputs a message with an audio | voice, and the display apparatus which displays and outputs a message.

(D) In the above embodiment, the operation of the open type combustion device is continued even after the replacement notification lamp 21 is turned on in step # 13. However, after the replacement notification lamp 21 is turned on, the replacement notification lamp 21 is opened. The mold combustion device may be stopped.

(E) The type of the CO sensor 17 is not limited to the semiconductor type as exemplified in the above embodiment, and various types of sensors such as a catalytic combustion type, an infrared type, an electrochemical type, etc. may be used. Is possible.

(F) In the above-described embodiment, the case where the present invention is applied to an open-type combustion apparatus including the burner 1 that uses gas fuel as the fuel has been illustrated. However, the present invention includes the burner 1 that uses liquid fuel as the fuel. The present invention can also be applied to an open combustion apparatus.
In addition, when the present invention is applied to an open combustion apparatus equipped with a burner 1 that uses gas fuel as fuel, the gas fuel is not limited to city gas mainly composed of methane, and may be propane gas, for example.

(G) In addition to the gas fan heater exemplified in the above embodiment, the present invention can be applied to various open-type combustion devices such as a gas stove, an oil fan heater, an oil stove, and a hot water supply device.

  As described above, it is possible to provide an open combustion apparatus that can further improve the safety against incomplete combustion.

DESCRIPTION OF SYMBOLS 1 Burner 4 Control means 5 Blowing means 8 Intake port 9 Outlet 10 Casing 13 Thermocouple 17 Incomplete combustion gas sensor A Sensor replacement notification means

Claims (7)

A burner for burning the supplied fuel;
A thermocouple that is equipped in contact with the flame formed by the burner and outputs a higher value as the temperature of the flame is higher,
An incomplete combustion gas sensor for detecting the concentration of incomplete combustion gas;
An open type combustion apparatus provided with a control means for detecting incomplete combustion of the burner based on detection information of the incomplete combustion gas sensor,
In a configuration in which the preset proper usable period is longer than that of the incomplete combustion gas sensor, the thermocouple,
The incomplete combustion gas in which the concentration of the incomplete combustion gas detected by the incomplete combustion gas sensor is obtained from the output of the thermocouple when the output of the thermocouple becomes equal to or lower than a preset determination value. An open-type combustion device provided with sensor replacement notification means for notifying that the incomplete combustion gas sensor needs to be replaced when it is out of an allowable range set based on the thermocouple output corresponding concentration.   The allowable range on the low concentration side on the low concentration side with respect to the thermocouple output corresponding concentration is set narrower than the high concentration side allowable range on the high concentration side with respect to the thermocouple output corresponding concentration. The open combustion apparatus according to 1. The determination set value can be set to an output of the thermocouple corresponding to a concentration in a predetermined range equal to or lower than an incomplete combustion gas concentration for detecting incomplete combustion of the burner,
The open combustion apparatus according to claim 1 or 2, wherein the allowable range is set narrower as the determination set value is set to an output of the thermocouple having a higher concentration of incomplete combustion gas.   The open combustion apparatus according to claim 1 or 2, wherein the set value for determination is set to an output of the thermocouple corresponding to an incomplete combustion gas concentration for detecting incomplete combustion of the burner. The incomplete combustion gas sensor is provided in a detachable state,
The said sensor replacement notification means is configured to notify that it is necessary to replace the incomplete combustion gas sensor when the time when the proper usable period of the incomplete combustion gas sensor expires is approaching. 5. The open combustion apparatus according to any one of 4 above.   The sensor replacement notifying means is configured to determine that the time when the appropriate usable period expires is approaching when the accumulated combustion time obtained by integrating the combustion time during which the burner burns reaches a preset notification setting time. The open-type combustion apparatus according to claim 5. Air outside the casing sucked through an intake port provided in a casing that houses the burner is supplied to the burner as combustion air, and combustion gas of the burner is discharged from a blowout port provided in the casing to the outside of the casing. Blowing means that ventilate so as to blow out is provided,
The said incomplete combustion gas sensor is provided in the said inlet or the vicinity of the said inlet so that the density | concentration of the incomplete combustion gas in the air inhaled through the said inlet may be detected. An open type combustion apparatus described in 1.

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