JP4043426B2 - Combustion equipment - Google Patents

Description

  The present invention relates to a combustion device.

  Here, an oil fan heater will be described as an example of a conventional combustion device. When the oil fan heater is ignited, first the vaporizer heater is turned on, the electromagnetic pump is operated to supply fuel from the fuel tank to the vaporizer, the fuel in the vaporizer is heated and gasified, and above the burner Turn on the ignition heater provided. And the solenoid provided in the vaporizer drives, a nozzle opens, and the gasified fuel is injected to a burner. Thus, a combustion flame is formed by the burner 0.5 seconds to 1 second after the normal solenoid is driven.

  The oil fan heater is provided with a flame detection electrode so as to be positioned in the combustion flame during normal combustion of the burner, and a voltage is applied between the flame detection electrode and the burner. For example, the potential of the flame detection electrode is set to + 24V, and the potential of the burner is set to 0V. If a combustion flame is formed at this time, a flame current that is an ionic current flows through the combustion flame from the flame detection electrode located in the combustion flame toward the burner.

  Then, the flame current flowing between the flame detection electrode and the burner is detected, and the presence or absence of the combustion flame is determined based on the comparison between the value corresponding to the detected flame current and the reference value. After a predetermined time (for example, 5 seconds) has elapsed from the determination, the ignition heater is turned off and the blower is turned on. Then, the ignition determination is performed after a predetermined time (for example, 60 seconds) has elapsed since the operation of the electromagnetic pump to start the fuel supply. A flame current flowing between the flame detection electrode and the burner is detected, and the presence or absence of ignition is determined based on a comparison between a value corresponding to the detected flame current and a reference value.

If it is determined in the ignition determination that ignition has occurred, the routine proceeds to normal operation. In normal operation, the combustion output and the fan speed are adjusted according to the difference between the room temperature and the set temperature. Further, in normal operation, the indoor oxygen concentration is monitored, and when the indoor oxygen concentration falls below a predetermined value (for example, 18%), a lamp is turned on to indicate that ventilation is required, a message display, etc. Fire extinguishing of the combustion apparatus (hereinafter referred to as ventilation fire extinguishing) is performed so that the oxygen concentration in the room does not further decrease due to combustion and / or combustion. When the oxygen concentration in the room decreases, the combustion state deteriorates and the flame current flowing between the flame detection electrode and the burner becomes smaller. Therefore, the oil fan heater reduces the flame current flowing between the flame detection electrode and the burner. And detecting whether or not the indoor oxygen concentration is less than the predetermined value based on a comparison between a value corresponding to the detected flame current and a predetermined value (ventilation reference value), If it is determined that the oxygen concentration is less than the predetermined value, ventilation warning and / or ventilation fire extinguishing is performed.
Japanese Patent Laid-Open No. 9-112894 JP-A-9-105521 JP-A-9-119632

  Silicon contained in cosmetics etc. floats in the room where combustion equipment such as oil fan heater is used. When this floating silicon enters the combustion flame, it burns and oxidizes, and burners and It adheres to the frame detection electrode. When silicon oxide adheres to the burner or the flame detection electrode, the flame current decreases as compared with the case where silicon oxide does not adhere. Accordingly, although the indoor oxygen concentration is not actually lower than the predetermined value, it is erroneously determined that the indoor oxygen concentration is lower than the predetermined value, and ventilation warning and fire extinguishing are unnecessary.

  In view of the above-mentioned problems, the present invention provides a combustion device (for example, a fan) that can reduce the problem of unnecessary ventilation warning and fire extinguishing due to silicon oxide adhering to the frame detection electrode and the burner. The object is to provide a heater.

In order to achieve the above object, a combustion apparatus according to the present invention includes a combustion device that generates heat by burning fuel, flame current detection means that detects a flame current of a combustion flame formed by the combustion device, and Silicon oxide adhesion amount estimation means for estimating the amount of silicon oxide adhering to the electrode through which the flame current flows, and a ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means Whether the oxygen concentration in the room in which the combustion equipment is installed is less than a predetermined value by comparing the ventilation reference value with the ventilation reference value changing means for changing the value and the value according to the signal from the flame current detection means determination means for determining whether, with the room temperature detecting means for detecting the temperature in the room where the combustion equipment is installed, the ventilation reference value changing means, room temperature is less than the predetermined value detected by said room temperature detecting means Ventilation reference value is varied according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means only in some cases, and when the room temperature detected by the room temperature detection means is a predetermined value or more, The ventilation reference value is set to a predetermined value regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means .

  According to such a configuration, since the ventilation reference value is changed according to the silicon oxide adhesion amount, it is erroneously determined that the indoor oxygen concentration is less than the predetermined value even though the indoor oxygen concentration is not less than the predetermined value. The possibility of being reduced can be reduced. Therefore, it is possible to reduce the possibility of unnecessary ventilation warning and ventilation fire extinguishing.

  If the oxygen concentration in the room is reduced due to the combustion of the combustion device before estimating the silicon oxide deposition amount, the flame current is reduced and the silicon oxide deposition amount is estimated too much. However, according to such a configuration, when the room temperature is equal to or higher than a predetermined value, the ventilation reference value is kept at a predetermined value regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means. Therefore, even when the indoor oxygen concentration is less than the predetermined value, it is possible to prevent a problem that the indoor oxygen concentration is not determined to be less than the predetermined value. In place of the room temperature detection means, a vaporizer temperature detection means for detecting the temperature of the vaporizer in the combustion apparatus is provided. May be. In addition to the room temperature detecting means, a vaporizer temperature detecting means for detecting the temperature of the vaporizer in the combustion apparatus is provided, and the case is classified depending on whether both the room temperature and the temperature of the vaporizer are less than a predetermined value. Also good. Further, in addition to the room temperature detecting means, a vaporizer temperature detecting means for detecting the temperature of the vaporizer in the combustion apparatus is provided, and the case classification is made depending on whether or not the value obtained by subtracting the room temperature from the temperature of the vaporizer is less than a predetermined value. May be.

  According to the present invention, it is possible to reduce the problem of unnecessary ventilation warning and fire extinguishing due to the silicon oxide adhering to the frame detection electrode and the burner.

  An embodiment of the present invention will be described with reference to the drawings. Here, an oil fan heater will be described as an example of the combustion device according to the present invention. FIG. 1 is a perspective view of an oil fan heater according to the present invention. The oil fan heater 1 has a vertically long, substantially rectangular parallelepiped shape, and a blowout port 2 for blowing warm air into the room is formed at the center of the front surface. Further, a suction port (not shown) for sucking indoor air is formed on the back surface of the oil fan heater 1. Further, an operation unit 3 provided with a display device for performing temperature display and error display, an operation switch, an operation display lamp, a temperature setting switch, and the like is formed on the oil fan heater 1.

  FIG. 2 is a schematic sectional side view of the oil fan heater 1. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. When the fan 5 rotates, air is sucked from the suction port 4, and the sucked air is discharged from the blower outlet 2 through the passage 6. The burner 7 burns the gasified fuel to generate heat, and warms the air passing through the passage 6. When the fan 5 rotates, part of the air from the fan travels downward from the back side of the combustion chamber, is sent to the burner side through the hole in the burner partition plate, and is supplied to the burner as primary air for combustion.

  FIG. 3 shows a control block diagram of the oil fan heater 1. In FIG. 3, the same parts as those in FIG. 2 are denoted by the same reference numerals, and detailed description thereof is omitted. The control unit 8 composed of a microcomputer responds to a signal output from the operation switch 9, a signal output from the temperature setting switch 10, a signal output from the room temperature sensor 11, and a signal output from the frame detection unit 12. The combustion device 13 and the motor 14 (hereinafter referred to as the fan motor 14) on which the fan 5 is attached to the rotating shaft are controlled. The combustion device 13 includes a fuel tank, an electromagnetic pump, a vaporizer, a vaporizer heater, a burner, and an ignition heater. The flame detection electrode of the flame detector 12 is provided so as to be positioned in the combustion flame when the burner is normally burned.

  The control operation of the control unit 8 will be described with reference to the control flowcharts of FIGS. 4 and 5. When the user presses the operation switch 9 of the oil fan heater 1 in the operation stop state, the control unit 8 inputs the output signal of the operation switch 9 and starts the control operation. First, the control unit 8 turns on the operation lamp of the operation unit 3 (step S10).

  The control unit 8 detects the room temperature detected by the room temperature sensor 11 (step S20), turns on the vaporizer heater (step S30), operates the electromagnetic pump, and supplies fuel from the fuel tank to the vaporizer. The fuel in the carburetor is heated and gasified, and the ignition heater provided above the burner 7 is turned on (step S40). And the solenoid provided in the vaporizer drives, a nozzle opens, and the gasified fuel is injected to a burner (step S50). Thus, a combustion flame is formed by the burner 0.5 seconds to 1 second after the normal solenoid is driven.

  The controller 8 applies a voltage between the frame detection electrode of the frame detector 12 and the burner of the fuel device 13 (step S50). For example, the potential of the flame detection electrode is set to + 24V, and the potential of the burner is set to 0V.

  The controller 8 measures the time T that has elapsed since the start of fuel supply by operating the electromagnetic pump using an internal timer, and determines whether or not the time T has reached 60 seconds (step S60). . If the time T has reached 60 seconds (Yes in step S60), the process proceeds to step S100 described later. On the other hand, if the time T has not reached 60 seconds (No in step S60), the control unit 8 sets the frame based on the value of the flame current flowing between the frame detection electrode and the burner detected by the frame detection unit 12. The impedance between the detection electrode and the burner is calculated, and it is determined whether or not the impedance is less than a reference value (6.3 MΩ) (step S70). The reference value is stored in advance in the memory of the control unit 8. If the impedance between the flame detection electrode and the burner is less than the reference value (Yes in step S70), the control unit 8 determines that there is a combustion flame (step S80), and proceeds to step S60. When it is determined that the combustion flame is present for the first time, the control unit 8 turns off the ignition heater of the combustion device 13 and rotates the fan motor 14 after a predetermined time (for example, 5 seconds) has elapsed from the determination time. On the other hand, if the impedance between the flame detection electrode and the burner is not less than the reference value (No in step S70), it is determined that there is no combustion flame (step S90), and the process proceeds to step S60.

  In step S100, the presence or absence of ignition is determined based on the determination of the presence or absence of the combustion flame. If not ignited (No in step S100), the operation of the combustion device 13 is stopped, the rotational drive of the fan motor 14 is stopped, and an error is displayed on the display device of the operation unit 3 (step S110). On the other hand, if it is ignited (Yes in step S100), the process proceeds to step S120 shown in FIG.

  If the indoor oxygen concentration has already fallen to some extent because the combustion device has burned before estimating the silicon oxide deposition amount, the flame current will decrease, so the silicon oxide deposition amount will actually be small. However, if the amount of silicon oxide attached is large, it is erroneously determined, the ventilation reference value becomes a large value, and there is a possibility that the ventilation warning and the fire extinguishing are not performed even if the indoor oxygen concentration becomes less than the predetermined value. For this reason, in step S120, it is determined whether the room temperature detected in step S20 is larger than a threshold value. The reference value is stored in advance in the memory of the control unit 8. If the room temperature detected in step S20 is larger than the threshold (Yes in step S120), there is a possibility that even if the silicon oxide adhesion amount is small, it may be erroneously determined that the silicon oxide adhesion amount is large. The value is kept at a predetermined value (1.0 MΩ in this embodiment), and the process proceeds to step S140. On the other hand, if the room temperature detected in step S20 is not larger than the threshold value (No in step S120), the control unit 8 estimates the amount of silicon oxide adhering to the frame detection electrode and the burner, and the estimated silicon oxide The ventilation reference value is varied according to the amount of adhesion (step S130). Specifically, the control unit 8 forces the combustion device 13 to perform combustion at a constant output heat quantity for a certain period of time immediately after the ignition determination, and the flame detection electrode and burner detected by the flame detection unit 12 at that time. The impedance between the flame detection electrode and the burner is calculated based on the value of the flame current flowing between and the silicon oxide, and the silicon oxide adhesion amount is estimated based on the impedance. If the impedance is large, it is estimated that the silicon oxide deposition amount is large, and if the impedance is small, it is estimated that the silicon oxide deposition amount is small. A data table corresponding to the ventilation reference value for each predetermined range of the silicon oxide adhesion amount is stored in advance in the memory of the control unit 8, and the control unit 8 estimates the silicon oxide adhesion amount based on the data table. Change the ventilation reference value accordingly. In this embodiment, if the estimated silicon oxide adhesion amount is less than a predetermined value, the ventilation reference value is set to a predetermined value of 1.0 MΩ, and if the estimated silicon oxide adhesion amount is equal to or greater than the predetermined value, ventilation is performed. The reference value is 2.0 MΩ. Then, after step S130, the process proceeds to step S140.

  The second silicon oxide adhesion amount estimation method may be adopted instead of the above-described silicon oxide adhesion amount estimation method (hereinafter referred to as the first silicon oxide adhesion amount estimation method). In the second silicon oxide adhesion amount estimation method, the control unit 8 measures the operation time of the combustion device using an internal timer, stores the accumulated operation time of the combustion device in the internal memory, and based on the accumulated operation time. Estimate the amount of silicon oxide attached. If the cumulative operation time is long, it is estimated that the silicon oxide adhesion amount is large, and if the cumulative operation time is short, it is estimated that the silicon oxide adhesion amount is small. However, since the amount of floating silicon differs depending on the place of use and the like, the second silicon oxide adhesion amount estimation method lacks accuracy compared to the first silicon oxide adhesion amount estimation method. When the second silicon oxide adhesion amount estimation method is employed, the processing in step S20 and step S120 is not necessary.

  Further, a third silicon oxide adhesion amount estimation method may be employed instead of the first or second silicon oxide adhesion amount estimation method. In the third silicon oxide deposition amount estimation method, the time until the controller 8 determines that there is a combustion flame after the solenoid is driven (from step S40 shown in FIG. 4 to step S70). The time until this process is performed, hereinafter referred to as the combustion flame detection time) is measured, and the silicon oxide adhesion amount is estimated based on the combustion flame detection time. If the combustion flame detection time is long, it is estimated that the silicon oxide adhesion amount is large, and if the combustion flame detection time is short, it is estimated that the silicon oxide adhesion amount is small.

  Here, three types of silicon oxide adhesion amount estimation methods have been described, but other methods may be used as long as the silicon oxide adhesion amount can be estimated.

  Then, the control unit 8 determines whether the impedance between the frame detection electrode and the burner is less than the ventilation reference value (step S140).

  If the impedance is not less than the ventilation reference value (No in step S140), it is determined that the oxygen concentration in the room is less than the predetermined value, and the fire extinguishing is performed (step S150). Display is performed (step S160). In addition, you may give a ventilation warning with ventilation fire extinguishing.

  On the other hand, if it is determined in step S140 that the impedance is less than the ventilation reference value (Yes in step S140), the control unit 8 determines that the indoor oxygen concentration is equal to or higher than the predetermined value, and does not perform ventilation fire extinguishing. Controls the output heat quantity of the combustion device 13 and the rotational speed of the fan motor 14 in accordance with the difference between the set temperature input by pressing the temperature setting switch 12 and the room temperature detected by the room temperature sensor 11 (step S170). ). That is, when the difference between the set temperature and the room temperature is large, the control unit 8 increases the output heat amount of the combustion device 13 and the rotational speed of the fan motor 14, and when the difference between the set temperature and the room temperature is small, the control unit 8 The output heat amount and the rotational speed of the fan motor 14 are reduced.

  In subsequent step S180, control unit 8 determines whether or not the room temperature is higher than the set temperature and whether or not pressing of operation switch 9 is detected. If it is determined that the room temperature is not higher than the set temperature and the pressing of the operation switch 9 is not detected (No in step S180), the process proceeds to step S140. On the other hand, if it is determined that the room temperature is higher than the set temperature and / or the pressing of the operation switch 9 is detected (Yes in Step S180), the control unit 8 extinguishes the combustion device 13 (Step S190). Specifically, according to the control command from the control unit 8, the combustion device 13 stops the electromagnetic pump and stops the supply of fuel from the fuel tank to the vaporizer.

  After a predetermined period has elapsed since the combustion device 13 extinguished, the control unit 8 stops the rotational drive of the fan motor 14 (step S200). The interior of the main body can be cooled by rotating the fan motor 14 until a predetermined period elapses after the combustion device 13 is extinguished.

  In continuing step S210, it is determined whether the control part 8 detected pressing-down of the operation switch 9. FIG. If it is determined that pressing of the operation switch 9 is detected (Yes in step S210), the operation lamp of the operation unit 3 is turned off (step S220), and the operation ends. On the other hand, if it is determined that pressing of the operation switch 9 is not detected (No in step S210), the control unit 8 determines whether the room temperature is lower than the set temperature by a predetermined value or more (step S230). If it is determined that the room temperature is lower than the set temperature by a predetermined value or more (Yes in step S230), the process proceeds to step S30 shown in FIG. If it is determined that the room temperature is not lower than the set temperature by a predetermined value or more (No in step S230), the process proceeds to step S210.

  Since the control unit 8 performs the control operation as described above, the ventilation reference value is determined according to the silicon oxide adhesion amount, so that the indoor oxygen concentration is not less than the predetermined value. It is possible to reduce the possibility of being erroneously determined to be less than the predetermined value. Therefore, it is possible to reduce the possibility of unnecessary ventilation warning and ventilation fire extinguishing. In the control flowcharts of FIGS. 4 and 5, the operation shifts to the ignition determination 60 seconds after the electromagnetic pump is started to start the fuel supply, the reference value is set to 6.3 MΩ, and the ventilation reference value is set to 2.0 MΩ. However, the number of levels of these specific values and ventilation reference values is only an example, and it is preferable to set optimum values according to the structure of the oil fan heater.

  However, when the control unit 8 performs the control operation according to the control flowcharts of FIGS. 4 and 5, it is caused by the fact that there is a combustion flame due to silicon oxide adhering to the flame detection electrode and the burner. The defect cannot be reduced. Therefore, it is desirable for the control unit 8 to perform any of the control operations described below.

  For example, the memory table of the control unit 8 stores in advance a data table in which the ventilation reference value and the reference value correspond to each predetermined range of the silicon oxide adhesion amount, and the room temperature detected by the control unit 8 in step S20 is stored. A step (hereinafter referred to as a reference value changing step) of changing the reference value according to the silicon oxide deposition amount (silicon oxide deposition amount estimated in step S130) based on the data table when it is less than the threshold value is performed in step S50. And step S60. Accordingly, it is possible to reduce the possibility that it is determined that the ignition is not ignited in spite of the formation of the combustion flame.

  Further, the control unit 8 may perform the control operation according to the control flowchart shown in FIG. 6 instead of the control flowchart shown in FIG. In FIG. 6, the same steps as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  Steps S10 to S50 are the same as those in the flowchart shown in FIG. The control unit 8 uses the internal timer to operate the electromagnetic pump to measure the time T that has elapsed since the start of fuel supply, and determines whether the time T has reached 60 seconds (step S240). . If the time T has reached 60 seconds (Yes in step S240), the process proceeds to step S310 described later. On the other hand, if the time T has not reached 60 seconds (No in step S340), the control unit 8 sets the frame based on the value of the flame current flowing between the frame detection electrode and the burner detected by the frame detection unit 12. The impedance between the detection electrode and the burner is calculated, and it is determined whether or not the impedance is less than the first reference value (5.9 MΩ) (step S250). The first reference value is stored in advance in the memory of the control unit 8. If the impedance between the flame detection electrode and the burner is less than 5.9 MΩ (Yes in step S250), the control unit 8 determines that there is a combustion flame (step S260), and proceeds to step S280. When it is determined that the combustion flame is present for the first time, the control unit 8 turns off the ignition heater of the combustion device 13 and rotates the fan motor 14 after a predetermined time (for example, 5 seconds) has elapsed from the determination time. On the other hand, if the impedance between the flame detection electrode and the burner is not less than 5.9 MΩ (No in step S250), it is determined that there is no combustion flame (step S270), and the process proceeds to step S240.

  In step S280, it is determined whether time T has reached 60 seconds. If the time T has reached 60 seconds (Yes in step S280), the process proceeds to step S310 described later. On the other hand, if the time T has not reached 60 seconds (No in step S280), it is determined whether or not the impedance between the frame detection electrode and the burner is less than the second reference value (7.4 MΩ). (Step S290). The second reference value is stored in advance in the memory of the control unit 8. If the impedance between the flame detection electrode and the burner is not less than 7.4 MΩ (No in step S290), the control unit 8 determines that there is no combustion flame (step S300), and proceeds to step S240. On the other hand, if the impedance between the flame detection electrode and the burner is less than 7.4 MΩ (Yes in step S290), the process proceeds to step S260 and it is determined that there is a combustion flame.

  In step S310, the presence or absence of ignition is determined based on the determination of the presence or absence of a combustion flame. If it is ignited (Yes in step S310), the process proceeds to step S120 shown in FIG. On the other hand, if not ignited (No in step S310), the operation of the combustion device 13 is stopped, the rotational drive of the fan motor 14 is stopped, and an error is displayed on the display device of the operation unit 3 (step S320).

  Whether or not the control unit 8 performs the control operation as described above to shift from the state without the combustion flame to the state with the combustion flame determines whether the impedance between the flame detection electrode and the burner is the first reference value. (5.9 MΩ) and whether the transition from the state with the combustion flame to the state without the combustion flame is determined by the impedance between the flame detection electrode and the burner and the second reference value (7 .4 MΩ). That is, hysteresis is provided in the determination of the presence or absence of the combustion flame.

  Here, FIG. 7 shows the relationship between the impedance between the flame detection electrode and the burner and the time T that has elapsed since the start of fuel supply by operating the electromagnetic pump. When ignition fails, the impedance between the flame detection electrode and the burner remains infinite (see characteristic line A). When silicon oxide is not attached to the burner or the flame detection electrode, immediately after the ignition, the impedance between the flame detection electrode and the burner becomes less than the first reference value (5.9 MΩ). Since the flame is unstable, even if the impedance between the flame detection electrode and the burner fluctuates, it does not exceed the first reference value (5.9 MΩ) (see characteristic line B). On the other hand, when silicon oxide adheres to the burner or the flame detection electrode, the flame current decreases, so that the impedance between the flame detection electrode and the burner is set to the first reference value (5.9 MΩ) by ignition. Since the flame is unstable immediately after ignition, the impedance between the flame detection electrode and the burner may fluctuate and exceed the first reference value (5.9 MΩ). (See characteristic line C). However, if the impedance between the flame detection electrode and the burner is not equal to or higher than the second reference value (7.4 MΩ), it is not determined that the combustion flame is present and the combustion flame is absent. The possibility that it is determined that the ignition is not ignited in spite of the formation of the flame can be reduced.

  After the room temperature becomes higher than the set temperature and the combustion apparatus is extinguished, when the room temperature becomes lower than the set temperature by a predetermined value or more, the combustion apparatus is re-ignited (see FIG. 5). In this case, since it is already in the operation state, the control unit 8 performs the control operation after step S30. Further, in the control flowchart of FIG. 6, 60 seconds after starting the fuel supply by operating the electromagnetic pump, the process proceeds to the ignition determination, the first reference value is set to 5.9 MΩ, and the second reference value is set to 7 However, these set values are merely examples, and optimal values may be set according to the structure of the oil fan heater.

  Further, the control unit 8 may perform the control operation according to the control flowchart shown in FIG. 8 instead of the control flowchart shown in FIG. In FIG. 8, the same steps as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  Steps S10 to S50 are the same as those in the control flowchart shown in FIG. The control unit 8 uses the internal timer to operate the electromagnetic pump to measure the time T that has elapsed since the start of fuel supply, and determines whether the time T has reached 50 seconds (step S330). . If the time T has reached 50 seconds (Yes in step S330), the control unit 8 rotates the fan motor 14 if the fan motor 14 is not driven to rotate and the ignition heater is turned on. The heater is turned off (step S340), and the process proceeds to step S350. On the other hand, if the time T has not reached 50 seconds (No in step S330), the process directly proceeds to step S350.

  In step S350, it is determined whether or not the time T has reached 60 seconds. If the time T has reached 60 seconds (Yes in step S350), the process proceeds to step S390 described later. On the other hand, if the time T has not reached 60 seconds (No in step S350), the control unit 8 detects the frame based on the value of the current flowing between the frame detection electrode and the burner detected by the frame detection unit 12. The impedance between the working electrode and the burner is calculated, and it is determined whether or not the impedance is less than the reference value (6.3 MΩ) (step S360). The reference value is stored in advance in the memory of the control unit 8.

  If the impedance between the flame detection electrode and the burner is less than the reference value (Yes in step S360), the control unit 8 determines that there is a combustion flame (step S370), and proceeds to step S330. If it is determined for the first time that there is a combustion flame, the controller 8 will burn if the fan motor 14 is not driven to rotate and the ignition heater is on after a predetermined time (for example, 5 seconds) has elapsed since the determination. The ignition heater of the device 13 is turned off, and the fan motor 14 is driven to rotate. On the other hand, if the impedance between the flame detection electrode and the burner is not less than the reference value (No in step S360), it is determined that there is no combustion flame (step S380), and the process proceeds to step S330.

  In step S390, the presence / absence of ignition is determined based on the determination of the presence / absence of the combustion flame. If it is ignited (Yes in step S390), the process proceeds to step S120 shown in FIG. On the other hand, if not ignited (No in step S390), the operation of the combustion device 13 is stopped, the rotational drive of the fan motor 14 is stopped, and an error is displayed on the display device of the operation unit 3 (step S400).

  By performing the control operation as described above, the control unit 8 performs a predetermined time (50 seconds) after starting the fuel supply by operating the electromagnetic pump at the latest regardless of the determination result of the presence or absence of the combustion flame. By the time, the fan motor 14 is driven to rotate. When silicon oxide is attached to the burner or flame detection electrode, the flame current decreases, so the impedance between the flame detection electrode and the burner is the reference value (even if there is a combustion flame). It may be determined that there is no combustion flame without being less than 6.3 MΩ), but even if it is determined that there is no combustion flame, the electromagnetic pump is operated and fuel supply is started. When a predetermined time (50 seconds) elapses, the fan motor 14 rotates and a part of the air from the fan travels downward from the back side of the combustion chamber and is sent to the burner side through the hole of the burner partition plate. The burner is supplied as combustion primary air, and the combustion flame is stabilized. This stabilization of the combustion flame reduces the impedance between the flame detection electrode and the burner. Accordingly, it is possible to reduce the possibility that it is determined that the ignition is not ignited in spite of the formation of the combustion flame.

  However, if the fan motor 14 is driven to rotate before the combustion flame is formed, the air flow hinders ignition. Therefore, the determination reference time (50 seconds) in step S330 is from the fuel tank of the combustion device 13 to the vaporizer. It is desirable that the time slightly longer than the time from the start of operation of the electromagnetic pump to the time when the gasified fuel is injected into the burner in a state where no fuel remains in the pipe.

  In the control flow chart of FIG. 8, the fan motor 14 is driven to rotate and the ignition heater is turned off by 50 seconds after starting the fuel supply by operating the electromagnetic pump at the latest to operate the electromagnetic pump. 60 seconds after starting the fuel supply, the ignition shift is made and the reference value is set to 6.3 MΩ. However, these set values are only examples, and optimum values are set according to the structure of the oil fan heater. Good.

  Further, the control unit 8 may perform the control operation according to the control flowchart shown in FIG. 9 instead of the control flowchart shown in FIG. In FIG. 9, the same steps as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  Steps S10 to S50 are the same as those in the flowchart shown in FIG. The control unit 8 counts the time T that has elapsed since the start of fuel supply by operating the electromagnetic pump using an internal timer, and determines whether or not the time T has reached 50 seconds (step S410). . If the time T has reached 50 seconds (Yes in step S410), the control unit 8 rotates the fan motor 14 if the fan motor 14 is not driven to rotate and the ignition heater is on, and the ignition is performed. The heater is turned off (step S420), and the process proceeds to step S430. On the other hand, if the time T has not reached 50 seconds (No in step S410), the process directly proceeds to step S430.

  In step S430, it is determined whether or not the time T has reached 60 seconds. If the time T has reached 60 seconds (Yes in step S430), the process proceeds to step S500 described later. On the other hand, if the time T has not reached 60 seconds (No in step S430), the control unit 8 sets the frame based on the value of the flame current flowing between the frame detection electrode and the burner detected by the frame detection unit 12. The impedance between the detection electrode and the burner is calculated, and it is determined whether or not the impedance is less than the first reference value (5.9 MΩ) (step S440). The first reference value is stored in advance in the memory of the control unit 8. If the impedance between the flame detection electrode and the burner is less than 5.9 MΩ (Yes in step S440), the control unit 8 determines that there is a combustion flame (step S450), and proceeds to step S470. When it is determined that the combustion flame is present for the first time, the control unit 8 turns off the ignition heater of the combustion device 13 and rotates the fan motor 14 after a predetermined time (for example, 5 seconds) has elapsed from the determination time. On the other hand, if the impedance between the flame detection electrode and the burner is not less than 5.9 MΩ (No in step S440), it is determined that there is no combustion flame (step S460), and the process proceeds to step S410.

  In step S470, it is determined whether or not the time T has reached 60 seconds. If the time T has reached 60 seconds (Yes in step S470), the process proceeds to step S500 described later. On the other hand, if the time T has not reached 60 seconds (No in step S470), it is determined whether or not the impedance between the frame detection electrode and the burner is less than the second reference value (7.4 MΩ). (Step S480). The second reference value is stored in advance in the memory of the control unit 8. If the impedance between the flame detection electrode and the burner is not less than 7.4 MΩ (No in step S480), the controller 8 determines that there is no combustion flame (step S490), and proceeds to step S410. On the other hand, if the impedance between the flame detection electrode and the burner is less than 7.4 MΩ (Yes in step S480), the process proceeds to step S450 and it is determined that there is a combustion flame.

  In step S500, the presence or absence of ignition is determined based on the determination of the presence or absence of a combustion flame. If it is ignited (Yes in step S500), the process proceeds to step S110 shown in FIG. On the other hand, if not ignited (No in step S500), the operation of the combustion device 13 is stopped, the rotational drive of the fan motor 14 is stopped, and an error is displayed on the display device of the operation unit 3 (step S510).

  Whether or not the control unit 8 performs the control operation as described above to shift from the state without the combustion flame to the state with the combustion flame determines whether the impedance between the flame detection electrode and the burner is the first reference value. (5.9 MΩ) and whether the transition from the state with the combustion flame to the state without the combustion flame is determined by the impedance between the flame detection electrode and the burner and the second reference value (7 .4 MΩ). That is, hysteresis is provided in the determination of the presence or absence of the combustion flame.

  When silicon oxide is attached to the burner or flame detection electrode, the flame current decreases, so that the impedance between the flame detection electrode and the burner is less than the first reference value (5.9 MΩ) by ignition. Since the flame is unstable immediately after ignition, the impedance between the flame detection electrode and the burner may fluctuate and exceed the first reference value (5.9 MΩ). However, if the impedance between the flame detection electrode and the burner is not equal to or higher than the second reference value (7.4 MΩ), it is not determined that the combustion flame is present and the combustion flame is absent. The possibility that it is determined that the ignition is not ignited in spite of the formation of the flame can be reduced.

  Further, the fan motor 14 is driven to rotate until a predetermined time (50 seconds) elapses after the operation of the electromagnetic pump is started and fuel supply is started at the latest regardless of the determination result of the presence or absence of the combustion flame. . When silicon oxide is attached to the burner or the flame detection electrode, the flame current is reduced. Therefore, even if there is a combustion flame, the impedance between the flame detection electrode and the burner is the second. Although it may be determined that there is no combustion flame when the reference value (7.4 MΩ) or more is reached, even if it is determined that there is no combustion flame, the electromagnetic pump is operated to start supplying fuel. When the time (50 seconds) elapses, the fan motor 14 rotates and a part of the air from the fan travels downward from the back side of the combustion chamber and is sent to the burner side through the hole in the burner partition plate. Is supplied as primary air for combustion, and the combustion flame is stabilized. This stabilization of the combustion flame reduces the impedance between the flame detection electrode and the burner. Therefore, it is possible to further reduce the possibility that it is determined that the ignition is not ignited in spite of the formation of the combustion flame.

  However, if the fan motor 14 is driven to rotate before the combustion flame is formed, the air flow hinders ignition. Therefore, the determination reference time (50 seconds) in step S410 is from the fuel tank of the combustion device 13 to the vaporizer. It is desirable that the time slightly longer than the time from the start of operation of the electromagnetic pump to the time when the gasified fuel is injected into the burner in a state where no fuel remains in the pipe.

  In the control flowchart of FIG. 9, the fan motor 14 is driven to rotate and the ignition heater is turned off by 50 seconds after starting the fuel supply by operating the electromagnetic pump at the latest to operate the electromagnetic pump. 60 seconds after the start of fuel supply, the process shifts to ignition determination, the first reference value is set to 5.9 MΩ, and the second reference value is set to 7.4 MΩ. However, these set values are examples. An optimal value may be set according to the structure of the oil fan heater.

  As shown in FIG. 10, a vaporizer temperature sensor 15 that detects the temperature of the vaporizer may be added to the configuration of FIG. In the oil fan heater having such a configuration, the above-described step S20 is replaced with the step of detecting the temperature of the vaporizer detected by the vaporizer temperature sensor 15, and the above-described step S120 is replaced with the substitute step of step S20. The same effect can be obtained even if it is replaced with the step of determining whether the temperature is higher than the threshold value. Further, in the oil fan heater having such a configuration, the above-described step S20 is replaced with a step of detecting the room temperature detected by the room temperature sensor 11 and the temperature of the vaporizer detected by the vaporizer temperature sensor 15, and the above-described step S120. Even if it replaces with the step which determines whether at least 1 of the room temperature detected by the substitution step of step S20 and the temperature of a vaporizer is larger than a threshold value, the same effect can be acquired. Further, in the oil fan heater having such a configuration, the above-described step S20 is replaced with a step of detecting the room temperature detected by the room temperature sensor 11 and the temperature of the vaporizer detected by the vaporizer temperature sensor 15, and the above-described step S120. If the value obtained by subtracting the room temperature detected in the substitute step in step S20 from the temperature of the vaporizer detected in the substitute step in step S20 is larger than the threshold value, the same effect can be obtained.

  Although the oil fan heater has been described as an example in the present embodiment described above, the present invention can also be applied to other combustion devices (for example, a gas fan heater).

These are the perspective views of the oil fan heater which concerns on this invention. These are schematic sectional side views of the oil fan heater which concerns on this invention. These are the control block diagrams of the oil fan heater which concerns on this invention. These are the first half parts of the control flowchart of the oil fan heater according to the present invention. These are the second half part of the control flowchart of the oil fan heater which concerns on this invention. These are the first half parts of the other control flowchart of the oil fan heater which concerns on this invention. These are figures which show the impedance between the electrode for flame | frame detection at the time of the control flow shown in FIG. 6, and a burner. These are the first half parts of the other control flowchart of the oil fan heater which concerns on this invention. These are the first half parts of the other control flowchart of the oil fan heater which concerns on this invention. These are the other control block diagrams of the oil fan heater which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Petroleum fan heater 2 Outlet 3 Operation part 4 Inlet 5 Fan 6 Passage 7 Burner 8 Control part 9 Operation switch 10 Temperature setting switch 11 Room temperature sensor 12 Flame | frame detection part 13 Combustion apparatus 14 Fan motor 15 Vaporizer temperature sensor

Claims (4)

A combustion device for generating heat by burning fuel;
Flame current detection means for detecting a flame current of a combustion flame formed by the combustion device;
Silicon oxide adhesion amount estimating means for estimating the amount of silicon oxide adhering to the electrode through which the flame current flows;
A ventilation reference value changing means for varying a ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means;
A determination means for comparing the value according to the signal from the flame current detection means and the ventilation reference value to determine whether or not the oxygen concentration in the room where the combustion equipment is installed is less than a predetermined value;
Room temperature detecting means for detecting the temperature of the room where the combustion equipment is installed,
The ventilation reference value changing means sets the ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means only when the room temperature detected by the room temperature detection means is less than a predetermined value. If the room temperature detected by the room temperature detecting means is greater than or equal to a predetermined value, the ventilation reference value is a predetermined value regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means. burning appliance characterized in that it remain. A combustion device for generating heat by burning fuel;
Flame current detection means for detecting a flame current of a combustion flame formed by the combustion device;
Silicon oxide adhesion amount estimating means for estimating the amount of silicon oxide adhering to the electrode through which the flame current flows;
A ventilation reference value changing means for varying a ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means;
A determination means for comparing the value according to the signal from the flame current detection means and the ventilation reference value to determine whether or not the oxygen concentration in the room where the combustion equipment is installed is less than a predetermined value;
And a vaporizer temperature detection means for detecting the temperature of the vaporizer before Symbol in a combustion apparatus,
The ventilation reference value changing means responds to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means only when the vaporizer temperature detected by the vaporizer temperature detection means is less than a predetermined value. If the temperature of the vaporizer detected by the vaporizer temperature detection means is equal to or higher than a predetermined value, the ventilation reference value is varied, regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means. Combustion equipment characterized in that the ventilation reference value is kept at a predetermined value. A combustion device for generating heat by burning fuel;
Flame current detection means for detecting a flame current of a combustion flame formed by the combustion device;
Silicon oxide adhesion amount estimating means for estimating the amount of silicon oxide adhering to the electrode through which the flame current flows;
A ventilation reference value changing means for varying the ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means;
A determination means for comparing the value according to the signal from the flame current detection means and the ventilation reference value to determine whether or not the oxygen concentration in the room where the combustion equipment is installed is less than a predetermined value;
Room temperature detecting means for detecting the temperature of the room in which the combustion equipment is installed, and vaporizer temperature detecting means for detecting the temperature of the vaporizer in the combustion device,
The amount of silicon oxide deposition is only when the ventilation reference value changing means has both the room temperature detected by the room temperature detecting means and the temperature of the vaporizer detected by the vaporizer temperature detecting means being less than a predetermined value. The ventilation reference value is varied in accordance with the silicon oxide adhesion amount estimated by the estimation means, and at least one of the room temperature detected by the room temperature detection means and the temperature of the vaporizer detected by the vaporizer temperature detection means is predetermined. If the value is equal to or greater than the value, the ventilation reference value remains at a predetermined value regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means. A combustion device for generating heat by burning fuel;
Flame current detection means for detecting a flame current of a combustion flame formed by the combustion device;
Silicon oxide adhesion amount estimating means for estimating the amount of silicon oxide adhering to the electrode through which the flame current flows;
A ventilation reference value changing means for varying the ventilation reference value according to the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means;
A determination means for comparing the value according to the signal from the flame current detection means and the ventilation reference value to determine whether or not the oxygen concentration in the room where the combustion equipment is installed is less than a predetermined value;
Room temperature detecting means for detecting the temperature of the room in which the combustion equipment is installed, and vaporizer temperature detecting means for detecting the temperature of the vaporizer in the combustion device,
The ventilation reference value changing means attaches the silicon oxide only when the value obtained by subtracting the room temperature detected by the room temperature detecting means from the temperature of the vaporizer detected by the vaporizer temperature detecting means is less than a predetermined value. A value obtained by subtracting the room temperature detected by the room temperature detecting means from the temperature of the vaporizer detected by the vaporizer temperature detecting means by varying the ventilation reference value according to the silicon oxide adhesion amount estimated by the quantity estimating means. If the air pressure is greater than or equal to a predetermined value, the ventilation reference value is kept at a predetermined value regardless of the silicon oxide adhesion amount estimated by the silicon oxide adhesion amount estimation means.

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