JPH0534442U - Open heater - Google Patents

Abstract

(57) [Summary] [Purpose] Oxygen concentration is accurately detected over a long period of time,
Allow efficient ventilation. [Structure] The output value of the O2 sensor 1 is corrected by the correction means 6 to a value at a predetermined temperature. This correction value is input to the alarm means 7, and an alarm is output when it is lower than the reference value, so ventilation is performed. If the room becomes equal to normal air after extinguishing the fire, the storage means 9 stores the correction value. Since the updating means 10 updates the reference value based on the stored correction value, the accuracy of the O2 sensor 1 can be maintained good for a long period of time.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 This invention relates to an open type heater such as an oil fan heater.

[0002]

[Prior Art]

 In general, this type of open-type heater consumes oxygen in the indoor air for its combustion, and at the same time, the combustion gas is discharged indoors. For this reason, especially in a well-sealed room, the oxygen concentration gradually decreases due to continued combustion, causing incomplete combustion. Ventilation should be performed occasionally (1-2 times per hour) to obtain fresh air. The user is instructed to replenish the fuel. ..

[0003]

[Problems to be solved by the device]

 By the way, when ventilating, it is necessary to endure cold for a short time when cold air flows in, and the comfort of the room is impaired because the indoor temperature is not stable for a while. Therefore, I would like to avoid ventilation if possible, but since information such as the oxygen concentration in the room is not provided, it is the actual situation that ventilation is performed even in a room where the oxygen concentration does not decrease. The present invention has been made in view of the above-mentioned problems, and the purpose thereof is to detect the oxygen concentration with high accuracy and provide the information to the user to enable efficient ventilation. To provide a machine.

[0004]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention detects the oxygen concentration in a room in an open type heater that takes in indoor air and burns it, discharges the resulting combustion gas into the room, and maintains the room temperature at a set temperature. An O2 sensor, a correction means for correcting the output value of the O2 sensor to a value at a predetermined temperature, and an alarm means for comparing the correction value and a reference value and outputting an alarm when the correction value <reference value. After the fire is extinguished, a configuration is adopted that has a storage unit that stores a correction value when the room is in a state that can be regarded as almost normal air, and an updating unit that updates the reference value based on the stored correction value. Is.

[0005]

[Action]

 With such a configuration, it is only necessary to open a window or the like when the alarm means outputs an alarm, so that efficient ventilation can be performed. Further, even if the output value of the O2 sensor is temperature-corrected and the reference value is updated using normal air even if the O2 sensor changes over time, the oxygen concentration detection accuracy can be kept good for a long time. Become.

[0006]

【Example】

 An embodiment of the present invention will be described in detail below with reference to the accompanying drawings. In FIGS. 1 and 2, 1 is a galvanic battery type O 2 sensor which is provided on the rear surface of the housing 3 of the fan heater 2 and detects the oxygen concentration in the room, and 4 is a temperature sensor which detects the room temperature. It is connected to the control unit 5. The control unit 5 has a correction means 6 for correcting the output value from the O2 sensor 1 to a value at a predetermined temperature (for example, 20 ° C.), and compares this correction value with a reference value (for example, a numerical value corresponding to an oxygen concentration of 19.5%). Then, an alarm means 7 for outputting an alarm when the correction value <reference value, a storage means 9 for storing the correction value when the interior of the room becomes almost normal air after the burner 8 is extinguished, and a memory. An updating unit 10 and the like that updates the reference value based on the corrected value is configured. Reference numeral 11 is a warm air fan, and 12 is an outlet.

Next, the operation of the above configuration will be described. When an operation switch (not shown) is operated, the burner 8 starts combustion for a while. Then, by driving the warm air fan 11, warm air is discharged from the air outlet 12 to heat it, and the heating power of the burner 8 changes so as to maintain the room temperature at the set temperature, and the oxygen concentration in the room is consumed by the combustion. . Therefore, the output value of the O 2 sensor 1 gradually decreases according to the characteristics shown by the solid line in FIG. 3, but the output value also changes depending on the room temperature as shown in FIG. 4, so in order to eliminate this influence. The correction means 6 temperature-corrects the output value to a value at a predetermined temperature.

When combustion continues and the correction value finally becomes equal to or less than the reference value, the alarm means 7 operates. At this time, an appropriate alarm such as a display and a sound is output, and the user performs ventilation, so that the oxygen concentration is quickly restored to 21% which is the concentration in normal air, and complete combustion is continued. Of course, when the oxygen concentration does not decrease due to poor room airtightness, etc., no alarm is output, so it is not necessary to ventilate.

When the operation switch is operated again to extinguish the burner 8, the oxygen concentration gradually increases thereafter as shown in FIG. 5 due to natural ventilation. When a considerable amount of time has passed since the fire was extinguished, the output value of the O2 sensor 1 becomes constant, and it is determined that the indoor air has become equal to normal air. After such a determination is made, the storage means 9 stores the correction value, and executes the operation at any time to store a predetermined number of correction values from the newest storage time. Note that it is desirable to store the correction value not immediately after the output of the O2 sensor 1 stabilizes, for example, immediately after the operation is started, in order to sufficiently secure the natural ventilation time. .

When the storage unit 9 stores a predetermined number or more of correction values as described above, the updating unit 10 selects the maximum correction value and uses this value to update the reference value. That is, the O2 sensor 1 changes with time, that is, the characteristics gradually change from the solid line to the dotted line in FIG. 3, and if the reference value is not calibrated, the oxygen concentration is slightly lowered and an alarm is output. This is because. The reason for using the highest correction value for calibration is to output an alarm on the safe side where the oxygen concentration is high, and to ensure a more complete match with normal air.

By thus updating the reference value at any time, the influence of the change over time of the O 2 sensor 1 can be eliminated, and in combination with the temperature correction of the correction means 6 described above, the oxygen concentration can be maintained for a long time. It will be possible to detect accurately over the entire range. Then, the new reference value is stored and used for the subsequent operation of the alarm means 7.

Although the number of reference values is one in the above-mentioned embodiment, a plurality of reference values may be used, and the first reference value is used for the output determination of the alarm as described above, and the second reference value is used for ventilation, that is, The configuration used for determining whether or not the oxygen concentration has become sufficiently high is arbitrary. Even in such a case, needless to say, each reference value is updated by the updating means 10.

[0013]

[Effect of the device]

 As described above, the open type heater of the present invention has an O2 sensor for detecting the oxygen concentration in the room, a correction means for correcting the output value of the O2 sensor to a value at a predetermined temperature, and the correction value and the reference value. Comparing the correction value <reference value, an alarm means for outputting an alarm, a storage means for storing the correction value when the room is considered to be almost normal air after extinguishing the fire, and a stored correction value And updating means for updating the reference value based on the above. Therefore, by opening a window etc. according to the output of the alarm, ventilation can be performed efficiently, the error due to the temperature of the O2 sensor is eliminated, and the reference value is updated at any time. It can be maintained satisfactorily.

Further, since the storage means stores a predetermined number or more from the newest correction value, and the updating means updates the reference value using the highest stored correction value, an alarm is issued on the safe side with a high oxygen concentration. Can be output, and the sensitivity of the O 2 sensor can be accurately corrected by achieving a more complete match with normal air, and so on.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating an open type heater according to an embodiment of the present invention.

FIG. 2 is a sectional view of an open type heater according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a relationship between oxygen concentration and an output value of an O 2 sensor.

FIG. 4 is a diagram illustrating a relationship between room temperature and an output value of an O 2 sensor.

FIG. 5 is a time series diagram for explaining changes in the oxygen concentration in the room.

[Explanation of symbols]

 1 O 2 sensor 6 correction means 7 alarm means 9 storage means 10 updating means

Claims (2)

[Scope of utility model registration request] 1. An open-type heater that takes in indoor air and burns it, discharges the resulting combustion gas into the room, and keeps room temperature at a set temperature. A correction means for correcting the output value to a value at a predetermined temperature, an alarm means for comparing the correction value with a reference value and outputting an alarm when the correction value is smaller than the reference value, and after the fire is extinguished, the room can be regarded as almost normal air. An open-type heater having a storage unit that stores a correction value when the state is reached, and an updating unit that updates the reference value based on the stored correction value. 2. The open type heating machine according to claim 1, wherein the storage means stores a predetermined number or more of the correction values from the newest one, and the updating means updates the reference value by using the maximum value of the stored correction values.