JP2012229847A - Hot-air heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-air heater which accurately carries out control based on information relating to a temperature change and operation state of each device inside the hot-air heater even when a temperature inside the hot-air heater increases higher than usual in a case that power feed is stopped in a state that a post purge after a finish of operation is not completely ended, and next operation is immediately started.SOLUTION: The hot-air heater includes a burner, a blower, an operation switch, a storage means, and a control device. Operation status information relating to a start and end of the post purge is written in the storage means, and the operation status information is retained by the storage means even when power feed is stopped after the operation ends. When the operation is started, it is determined whether the power feed is stopped or not in a period from when the post purge is started to when the post purge is ended in a previous operation. Blowing operation for operating the blower before ignition of the burner is carried out based on a determination result.

Description

  The present invention relates to a hot air heater that performs heating with hot air, and more particularly to a combustion-type hot air heater that incorporates a burner.

  Conventionally, there has been known a hot air heating apparatus having a structure in which a burner and a blower are built in a housing, a flame is generated by the burner, and combustion gas generated at the time of the flame is diluted with a large amount of air and released to the outside of the housing. It has been.

Such a hot air heating apparatus includes a hot air heating apparatus that includes a control device and temperature detection means, and controls each device such as a burner, a blower, and an electromagnetic valve based on temperature information detected by the temperature detection means. . In such a warm air heater, heating operation according to the difference between the set target room temperature and the detected current room temperature is possible, and the indoor ambient temperature can be efficiently raised and maintained.
There is also a hot air heater that includes a control device, an internal temperature detection means, and various sensors, and acquires information related to temperature changes and operation states of each device during operation. In such a warm air heater, when a failure has occurred in any of the devices, error information relating to the failure that has occurred can be displayed. Therefore, it is easy to identify a device in which a failure has occurred during repair or inspection prior to repair, and the cost of inspection and repair can be reduced.

  However, in this type of hot air heating device, when a power failure occurs during operation, there is a problem that the acquired target room temperature information, room temperature information, information on temperature changes and operation states of each device are erased. . That is, in the heating operation device, gas or the like is supplied to the burner via a normally closed electromagnetic valve that is open when energized. Therefore, when a power failure occurs, the solenoid valve is automatically closed and the burner is extinguished. Moreover, in order to improve the safety at the time of use of a warm air heating apparatus, even if a power supply returns, a solenoid valve does not return automatically, but a burner is ignited again by performing artificial operation. Here, in the conventional hot air heating apparatus, the information regarding the operation state is erased by a power failure. For this reason, when restarting after recovery from a power failure, the user has to set the target temperature again. In addition, erroneous error information is displayed, which makes it difficult to identify a device that has failed during repair.

  As a technique for solving such a problem, there is a technique disclosed in Patent Document 1. In the hot air heating device disclosed in Patent Document 1, various information acquired during operation is written in the nonvolatile storage means. Then, when a power failure occurs during operation, the power is then re-energized, and when the user performs a manual operation to re-ignite the burner, the operation is resumed based on the nonvolatile storage means. Thus, even if a power failure occurs during operation, the operation can be continued after re-energization in the same manner as before the power failure.

JP-A-11-344222

  However, in the hot-air heating device disclosed in Patent Document 1, when a power failure occurs during operation, the operation can be continued after re-energization, but again after the burner operation is completed by human operation. When the power supply is stopped before the ignition of the burner is started, there is a problem that the operation state during that time cannot be taken over.

  More specifically, when a hot air heater is used in a general household, the hot air heater during operation (combustion) is temporarily moved to another place for reasons such as the user cleaning the room. After moving to, it may be returned to its original position and used again. At this time, the user turns off the operation switch, extinguishes the hot air heater, removes the plug from the outlet, and stops power supply to the hot air heater. Then, after the hot air heater is moved and cleaned, the hot air heater is returned to its original position. Then, the plug is inserted into the outlet, the operation switch is turned on again, and the operation of the hot air heater is started.

  That is, when the hot air heater is used, there is a situation where the combustion operation of the burner is stopped and then the combustion operation is restarted in a short time, and the energization is temporarily stopped during that time.

  In the hot air heater, so-called post purge is performed after the operation is completed (after the burner is extinguished). Post purge is an operation in which ventilation and cooling are performed by blowing air for a certain period of time inside the casing and in the combustion case in a state where the combustion operation in the burner is stopped. Specifically, after the operation switch of the hot air heater is turned on and the combustion operation is started, the combustion operation is ended by turning off the operation switch. At this time, after the operation switch is turned off, the post-purge is performed for the purpose of removing the combustion gas remaining in the hot air heating device or removing the residual heat inside.

  Therefore, if power supply is stopped immediately after combustion of the burner is stopped, power supply to the hot air heater is stopped during post purge. Here, when the post-purge is being performed, the combustion of the burner is stopped. For this reason, even if the power supply is stopped, the operation status is not taken over after the power re-supply. As a result, even if power supply is stopped during post-purge execution, post-purge is not continuously performed after power re-supply.

  As a result, when the power supply is stopped immediately after the combustion of the burner is stopped, and when the combustion of the burner is started immediately after the power is supplied again, the next combustion operation is started in a state where the post purge is not completely completed. As a result, the combustion operation is started while the internal temperature of the warm air heater is considerably increased. However, if the hot air heater is operated in such a state, the sensor such as the internal temperature detecting means detects a value different from the normal state. There is a problem that control based on information cannot be performed accurately. That is, in many cases, the control device recognizes that the device is out of order, an error is displayed, and the subsequent operation is automatically stopped.

  Accordingly, the present invention has been made in view of the above-described problems of the prior art, and the object of the present invention is to stop power supply in a state where post-purge after completion of the combustion operation is not completely completed, and immediately It is an object of the present invention to provide a warm air heating device that can accurately perform control based on information on temperature changes and operation states of each device during operation even when the combustion operation of is started.

  The invention according to claim 1 for solving the above-mentioned problem has a burner, a blower, an operation switch, a storage means, and a control device, and starts heating operation based on an input signal from the operation switch. And the heating operation stop, and when the heating operation is stopped, the blower is operated to perform the post purge, and the control device stores the operation status information related to the start and end of the post purge. When the heating is started by the signal from the operation switch after the energization from the external power supply is stopped and the heating operation is started by the signal from the operation switch, the post-purge is started in the operation before the re-energization. In the hot air heating apparatus, the control device determines whether or not the energization is stopped before the post purge is completed.

  The hot air heating apparatus of the present invention can acquire and store information related to the operation status of the post purge after the burner burns. Specifically, it is possible to store information related to whether or not post-purge has been started, whether or not post-purge is being executed, and whether or not post-purge has been completed based on storage means. When the power supply from the external power supply is stopped after the start of the post-purge, and then the heating operation is started after the power supply is re-supplied after that, the post-purge ends normally before the power supply stops based on the information in the storage device It can be determined whether or not. That is, when the energization is stopped before, it can be determined whether or not it is from the start of the post purge to the end of the post purge. Therefore, for example, the air blowing operation can be performed based on the determination result. Therefore, even if energization is stopped during the post-purge, the post-purge can be substantially completed by the hot air heating device performing the air blowing operation when the operation is resumed. Therefore, the combustion gas remaining in the hot air heating device and the residual heat can be reliably removed, so that the operation can be performed without causing problems caused by these. Moreover, since the warm air heating device can be sufficiently cooled, the inside of the warm air heating device can be shifted from a considerably heated state to a normal state. From this, since various sensors can be operated in a normal state, an accurate value can be detected, and control based on information on temperature change and operation state of each device during operation can be accurately performed. Moreover, the threshold value of the detection value detected by various sensors can be changed or the subsequent operation procedure can be changed based on the determination result.

  The invention according to claim 2 includes first temperature detecting means for detecting the internal temperature of the hot air heater and second temperature detecting means for detecting the temperature of the burner or the vicinity of the burner, and the second temperature detecting means. The burner is ignited on the condition that the detected value is lower than the predetermined ignition reference value, and energized between the start of the post purge and the end of the post purge. When the ignition is stopped by the burner after the air blowing operation, the ignition reference value is set to the normal heating operation based on the temperature detected by the first temperature detecting means or the second temperature detecting means. It is set as the re-ignition reference value larger than the said ignition reference value at the time of a start, It is a warm air heating apparatus of Claim 1 characterized by the above-mentioned.

  According to this configuration, when ignition is performed in the burner after the air blowing operation, the ignition reference value is set to a re-ignition reference value larger than the ignition reference value at the start of normal heating operation, based on the temperature detected by the temperature detecting means. To do. Therefore, after the air blowing operation, when the internal temperature of the hot air heater becomes a specific temperature, the ignition operation can be performed even if the temperature is higher than the normal reference temperature. In other words, since the power supply is stopped without completing the post-purge, the ignition operation can be reliably performed even when the internal temperature of the hot air heater is relatively high. In addition, since the ignition operation can be performed without waiting until the internal temperature of the hot air heater becomes below the normal reference temperature from a state where the internal temperature of the hot air heater is relatively high, quick ignition is possible when the operation is resumed after energization. Operation is possible.

  According to a third aspect of the present invention, the second temperature detecting means is a burner sensor that generates a voltage according to a burner or a temperature in the vicinity of the burner, and the ignition reference value is a predetermined reference voltage value, (2) The burner is ignited on the condition that the voltage value of the voltage generated by the temperature detecting means is below the ignition reference value, and the post purge is completed after the post purge is started. If the energization has been stopped until the start, the reference voltage is determined based on the temperature detected by the first temperature detection means or the second temperature detection means when ignition by the burner is performed after the air blowing operation. The warm air heating device according to claim 2, wherein the value is set to a reignition reference value larger than the ignition reference value at the start of normal heating operation.

  According to such a configuration, the second temperature detection means is a burner sensor (for example, a thermocouple) that generates a voltage corresponding to the temperature of the burner or the vicinity of the burner. Therefore, the present invention is implemented at a relatively low cost compared to other sensors. be able to. In addition, highly accurate and stable measurement can be performed in a high temperature range.

  In the invention according to claim 4, when energization is stopped between the start of the post purge and the end of the post purge, the blowing operation is performed. The warm air heating device according to claim 2 or 3, wherein the cooling operation is started on condition that the first temperature detecting means has reached a predetermined cooling operation start temperature or more.

  According to such a configuration, the cooling operation is started when the internal temperature of the hot air heater reaches a predetermined cooling operation start temperature after the air blowing operation. As a result, even if the inside of the hot air heater cannot be cooled within a predetermined time by the air blowing operation, the internal temperature of the hot air heater is not excessively raised. It can be used more safely.

  The hot air heating apparatus of the present invention can store operating status information after the operation is completed. For this reason, even if the power supply is stopped during post-purge after the end of operation, it can be appropriately dealt with, and the operation is not stopped silently. For example, the post purge can be substantially completed by performing the air blowing operation based on the information before the power supply is stopped after the operation is resumed. From this, even if the operation is started in a state in which the inside of the hot air heating apparatus is considerably heated, there is an effect that the inside of the hot air heating apparatus can be shifted from the state in which it is considerably heated to the normal state. is there. As a result, various sensors can be operated in a normal state, so that there is an effect that the control based on the information on the temperature change and the operation state of each device during operation can be accurately performed.

It is a perspective view which shows the warm air heating apparatus concerning embodiment of this invention. It is a perspective view which shows the state which looked at the warm air heating apparatus of FIG. 1 from another direction. It is a front view which shows the state which removed the member which comprises a front surface from the warm air heating apparatus of FIG. 1, and opened the front. It is a schematic side sectional view of the hot air heating device of FIG. It is a flowchart which shows the procedure of the overheating condition confirmation control in the warm air heating apparatus of FIG. It is a flowchart which shows the procedure of the excessive temperature rising prevention control in the overheating condition confirmation control of FIG. It is a flowchart which shows the procedure of the safety confirmation control before ignition among the overheating condition confirmation controls of FIG.

  Embodiments of the present invention will be further described below. In the following description, the vertical / horizontal / front / rear relationship will be described with reference to the vertical / horizontal / front / rear relationship in FIG.

The hot air heating device 1 of this embodiment is a gas fan heater that is used by being placed on an indoor floor, and includes a substantially rectangular parallelepiped casing 2 as shown in FIGS. The casing 2 incorporates a combustion case 3, a blower 4, a control device 5, a room temperature detection thermistor 6, and an internal temperature detection thermistor 7 (first temperature detection means) as main members.
And this hot air heating apparatus 1 becomes a structure by which electric power is supplied from the electric power feeding system (for example, code | cord | chord with a power plug and outlet) which is not shown in figure, each apparatus, such as the air blower 4, and control apparatus 5 grade | etc., Operate.

  As shown in FIGS. 1 and 2, the housing 2 is provided with an operation panel 9 on its top surface. Further, a housing side exhaust port 10 is provided on the front side (see FIG. 1), and a housing side intake port 11 is provided on the back side (see FIG. 2). All of these communicate the internal space of the housing 2 with the outside.

  The operation panel 9 includes various input devices including the operation switch 8 and a display device. The operation panel 9 is connected to the control device 5 inside the housing 2 and can transmit information input by the user through various input devices to the control device 5. Further, the information transmitted from the control device 5 can be displayed on the display device. The operation switch 8 is a switch for starting or stopping a heating operation described later when pressed.

  As shown in FIG. 1, the housing-side exhaust port 10 is provided in the lower part of the front surface of the housing 2 and is located below the decorative plate 12. The housing-side exhaust port 10 is covered from the outside by a louver 13 having a substantially rectangular shape in front view. Although not shown, the housing-side exhaust port 10 has a substantially rectangular shape that is shorter in the left-right direction (width direction) than the louver 13 and slightly shorter in the up-down direction (height direction). . And the housing side exhaust port 10 is provided in the position from the left end from the center part (not shown). That is, the housing-side exhaust port 10 is an opening that extends from the vicinity of the left end to a position slightly closer to the center in the width direction than the right end in the lower front portion of the housing 2.

  As shown in FIG. 2, the housing-side intake port 11 has a substantially rectangular shape and is provided over most of the back surface of the housing 2. At this time, the housing-side intake port 11 is provided at a position from the left end (position from the right end in FIG. 2), and is provided at a position slightly above the center in the height direction. The housing side intake port 11 is covered from the outside by the filter 14 over the entire surface.

  As shown in FIG. 3, the combustion case 3 has a substantially rectangular parallelepiped shape that is shorter in the left-right direction (width direction) than the housing 2 and slightly shorter in the vertical direction (height direction) and depth direction (front-rear direction). It is a box body. And the combustion case 3 is distribute | arranged to the part from the left end in the housing 2. As shown in FIG.

Further, as shown in FIG. 4, the combustion case 3 incorporates a combustion mechanism including a burner 17, a thermocouple 18 (second temperature detecting means), a spark plug 19, and the like. The burner 17 can be supplied with fuel gas from a gas supply path and a gas nozzle (not shown).
Further, a blower 4 is built in the vicinity of the lower end of the combustion case 3. That is, the lower part of the combustion case 3 constitutes a fan case, and the combustion case 3 is a combustion case integrated with a fan case.

  Here, a substantially rectangular case-side exhaust port 22 is provided in the lower front portion of the combustion case 3. The case-side exhaust port 22 penetrates the front surface of the combustion case 3 and communicates the inside and the outside of the combustion case 3. In addition, this case side exhaust port 22 is formed in the front of the part in which the air blower 4 is incorporated, and exists in the position which opposes the above-mentioned housing side exhaust port 10 of the housing 2 mentioned above.

  Further, as shown in FIG. 4, a case side intake port 23 for supplying primary air and secondary air to the inside of the combustion case 3 is provided on the back side of the combustion case 3. The inside and the outside of the combustion case 3 are in communication with each other through 23. Although not shown, the case-side intake port 23 has a substantially rectangular shape, is in a position facing the housing-side intake port 11, and has an opening area smaller than that of the housing-side intake port 11.

  The blower 4 is a so-called DC fan, and includes a DC fan motor 4a and a substantially cylindrical impeller 4b as shown in FIG. 3, and the rotation of the DC fan motor 4a. Accordingly, the air is caused to flow by rotating the impeller 4b. At this time, the rotational speed (rotational speed) per unit time of the DC fan motor 4a and the impeller 4b can be varied, and the amount of air blown out is increased or decreased in proportion to the rotational speed.

  The control device 5 has a control board including a microcomputer (not shown) for controlling the hot air heating device 1 and a non-volatile storage means 25 (storage means), and the operation of each part of the hot air heating device 1 Can be controlled.

Specifically, the control device 5 can acquire signals from various temperature sensors (thermistors) of the hot air heater 1, the thermocouple 18, etc., and the ignition information such as the presence / absence of flame of the burner 17 and the combustion amount, It is possible to acquire temperature information such as the temperature inside the housing 2, the room temperature of the room in which the hot air heater 1 is installed, operation status information related to the operation of each part, and the like. And each part of the warm air heating apparatus 1 can be controlled based on the acquired information.
Furthermore, the control device 5 is connected to the DC fan motor of the blower 4 and can vary the rotational speeds of the DC fan motor 4a and the impeller 4b of the blower 4.
The control device 5 is connected to a burner 17, various control valves (not shown) such as an electromagnetic valve and a proportional valve provided in a gas supply path for supplying fuel gas to the burner 17, and an ignition plug 19. Yes. Thereby, a combustion start operation, a combustion stop operation, and an operation for increasing or decreasing the combustion amount can be performed on the burner 17.

  The nonvolatile storage means 25 is a nonvolatile memory in which stored information is not erased even when power supply to the hot air heating device 1 is stopped, and more specifically, is an EEPROM.

  The room temperature detection thermistor 6 is provided in the vicinity of the right end (left end in FIG. 2) of the housing-side intake port 11 as shown in FIGS. That is, it is provided at a position away from the combustion case 3 and is not easily affected by the radiant heat of the combustion case 3. The room temperature detecting thermistor 6 is a room temperature detecting means capable of acquiring the atmospheric temperature of the room (space) in which the hot air heater 1 is installed.

  As shown in FIGS. 1 to 3, the internal temperature detection thermistor 7 is placed on the upper surface of the combustion case 3, more specifically, a portion from the left end of the combustion case 3, in the front-rear direction. It is provided slightly ahead of the center. The internal temperature detection thermistor 7 can acquire the temperature of the combustion case 3 or the vicinity thereof.

Next, the outline | summary of operation | movement of the warm air heating apparatus 1 shown to this embodiment is demonstrated.
The warm air heating device 1 of this embodiment can start and stop the warm air heating device 1 by operating the operation switch 8. When the operation switch 8 is turned on, the burner 17 is ignited by a signal from the operation switch 8 to enter a heating operation state in which the room temperature is raised and maintained. Moreover, it switches to the heating operation stop state which waits in the state which the burner 17 and the air blower 4 stopped according to predetermined conditions, such as room temperature rising. That is, when the hot air heating apparatus 1 is in the heating operation state, the burner 17 burns fuel gas, and the blower 4 blows out hot air generated by stirring the generated combustion gas and air (hereinafter referred to as combustion operation). The temperature of the room can be raised to a set temperature. In the heating operation state, when the room temperature reaches the set temperature, the combustion operation and the operation for temporarily stopping the combustion of the fuel gas in the burner 17 (hereinafter referred to as the combustion stop operation) are alternately performed. By carrying out, the room temperature can be maintained at the set temperature. This will be specifically described below.

  When the operation switch 8 of the operation panel 9 is pressed and the heating operation of the hot air heater 1 is started, the control device 5 writes the operation status information related to the start of the heating operation into the nonvolatile storage means 25. To implement. First, overheat status confirmation control (details will be described later) is performed. When it is confirmed in the overheat state confirmation control that the previous burner combustion operation has ended normally and the post purge has ended normally, the warm air heating device 1 performs the heating operation start operation in a normal state. carry out. More specifically, when it is confirmed that the operation switch 8 is artificially operated to stop the combustion and the post purge is performed for a predetermined time, the warm air heating device 1 is in a normal state. The start operation of the heating operation in is performed. At this time, the control device 5 starts the blower 4 and, after a predetermined time has elapsed, energizes a solenoid valve (not shown), supplies gas to the burner 17, operates the spark plug 19, and forms a flame in the burner 17. Perform the ignition operation. When performing the ignition operation, if the voltage value of the voltage generated by the thermocouple 18 exceeds the ignition reference value A1 (for example, 3 mV) for a predetermined time (for example, 60 seconds) or more, some abnormality has occurred. Judgment is made and the ignition operation is stopped. In short, when the voltage generated by the thermocouple 18 is high, it means that the temperature of the portion where the thermocouple 18 is inserted is high, and there is a possibility that afterburning occurs in the burner 17. In this case, the ignition operation is stopped because there is a fear of a serious failure. Also, in principle, an error operation is performed and it is not possible to proceed to the subsequent steps.

  On the other hand, when the ignition operation is normally performed and the control device 5 confirms that a flame is formed in the burner 17, the blower 4 is operated to start the combustion operation.

  At this time, by operating the blower 4, an air flow that circulates through the housing 2 is formed in the vicinity of the warm air heating device 1. More specifically, as shown in FIG. 4, air is taken into the housing 2 from the housing intake port 11, and the air taken into the housing 2 is further fed into the combustion case 3 from the case-side intake port 23. It is taken in. A part of the air taken into the combustion case 3 is used for the combustion operation of the burner 17 as primary air or secondary air. Further, another part of the taken-in air is agitated with the combustion gas generated from the burner 17 and becomes hot air. Then, the air that has become warm air flows downward of the combustion case 3, blows out from the case side exhaust port 22 to the outside of the combustion case 3, and blows out from the case side exhaust port 10 to the outside of the case 2.

  Thus, in the warm air heating apparatus 1 of this embodiment, indoor temperature can be raised by taking in indoor air, heating it, and blowing it out.

  Here, the control device 5 continues to acquire the room temperature by the room temperature detection thermistor 6 when the hot air heating device 1 is in the heating operation state. That is, while the warm air heating device 1 is performing the heating operation, the control device 5 performs an operation of acquiring the room temperature at regular time intervals (or always).

  Then, during the combustion operation, the control device 5 compares the acquired room temperature with the target room temperature, and varies the rotational speed of the blower 4 based on the comparison result.

  In addition, the control device 5 compares the room temperature acquired by the room temperature detection thermistor 6 with the set target room temperature at regular intervals (or always) while the warm air heating device 1 is in the heating operation, and compares Based on the result, either the combustion operation or the combustion stop operation is performed. Specifically, for example, when the room temperature acquired during the combustion operation reaches the target room temperature, the control device 5 closes various control valves (not shown) provided in the gas supply path to the burner 17. As a result, the supply of the fuel gas to the burner 17 is shut off, the combustion in the burner 17 is stopped, and the operation is switched to the combustion stop operation. When the room temperature acquired during the combustion stop operation falls below the target room temperature beyond the predetermined temperature range, various control valves (not shown) provided in the gas supply path to the burner 17 are opened again, and the burner 17 is re-ignited to switch to combustion operation.

  When the burner 17 is re-ignited, the burner 17 is re-ignited on the condition that the voltage value of the voltage generated by the thermocouple 18 is lower than the re-ignition reference value A2 (for example, 10.5 mV). . At this time, if the condition is not satisfied within the predetermined time, it is determined that some abnormality has occurred, and the re-ignition operation is stopped.

  That is, the warm air heating device 1 of the present embodiment can prevent the room temperature from excessively rising by temporarily performing the combustion stop operation during the combustion operation, and can maintain the room temperature at the target room temperature. At this time, when the burner 17 is re-ignited, the ignition operation is performed even at a higher temperature than during normal ignition.

  When the operation switch is turned off and the heating operation of the hot air heater 1 is finished, the control device 5 closes various control valves (not shown) provided in the gas supply path to the burner 17. Then, the supply of the fuel gas to the burner 17 is shut off, and the combustion in the burner 17 is stopped. Then, with the combustion of the burner 17 stopped, the blower 4 is operated at a predetermined rotational speed, and post purge is started. At this time, the control device 5 writes the operation status information related to the end of the heating operation and the start of the post purge to the nonvolatile storage means 25. Then, post purge is performed. When the predetermined time has elapsed and the post purge is normally completed, the control device 5 writes the operation status information related to the completion of the post purge to the nonvolatile storage means 25.

  Here, in the warm air heating device 1 of the present embodiment, when the operation switch 8 is pressed again and the heating operation is started again, first, the overheat status confirmation control for confirming the overheat status inside the warm air heating device 1 is performed. To do. The overheat status confirmation control, which is a characteristic operation of the present embodiment, will be described in detail below with reference to FIGS.

  In the overheating state confirmation control of the present embodiment, the safety confirmation control before ignition is performed after the excessive temperature rise prevention control is performed. When an abnormality is detected in either the excessive temperature rise prevention control or the safety confirmation control before ignition, a safety operation is performed, and the operation is terminated without performing the heating operation.

  When the operation switch 8 is pressed and the heating operation is started, as shown in step 1 of FIG. 5, the control device 5 performs the previous operation based on the operation state information stored in the nonvolatile storage means 25. It is determined whether the power supply is stopped during the post purge. That is, when the energization is stopped between the post purge start time and before the post purge end time and the operation is terminated, it is determined that the power supply is stopped during the post purge. Specifically, only the information that the post purge is started is stored, and if the information that the post purge is completed is not stored, it is determined that the power supply is stopped during the post purge.

  Here, when it is confirmed that the post-purge has been completed in the previous operation, the routine proceeds to step 7 and the ignition operation similar to the normal state is performed. Then, the heating operation is performed (step 6), and the excessive temperature rise prevention control is terminated.

  On the other hand, when the post purge is not completed in the previous operation, there is a possibility that heat remains in the apparatus. The various sensors detect the heat and execute a predetermined operation. However, if the heat remains and the temperature sensor (for example, the thermocouple 18 or the internal temperature detection thermistor 7) detects a high temperature. Even that is not a temperature sensor abnormality. Also, there is no residual fire, and it is not a malfunction of the solenoid valve or the like. Therefore, if it is clear that the equipment has stopped in a state where post-purge has not been completed, if the threshold values of various temperature sensors are left as they are, the abnormal or Determined to be a failure. Therefore, in this embodiment, when it is clear that the device has stopped in a state where the post-purge is not completed, an operation different from the normal operation is executed, and the threshold value of each temperature sensor is changed. Specifically, the process proceeds to step 2 to perform excessive temperature rise prevention control. The excessive temperature rise prevention control of this embodiment will be described in detail with reference to FIG.

  When the excessive temperature rise prevention control is started, the operation of the blower 4 is first started (step 21), and the air blowing operation is started. At this time, the rotation speed of the blower 4 is lower than that of the pre-purge.

  When the air blowing operation is started, the control device 5 first compares the internal temperature Tx of the housing 2 detected by the internal temperature detection thermistor 7 at the start with a first reference temperature Ta (for example, 80 degrees Celsius) ( Step 22). At this time, if the internal temperature Tx is equal to or lower than the first reference temperature Ta (YES in step 22), the excessive temperature rise prevention control is terminated.

  On the other hand, when the internal temperature Tx is higher than the first reference temperature Ta (NO in step 22), the control device 5 causes the internal temperature detection thermistor 7 until a predetermined time ta (for example, 50 seconds) elapses. The internal temperature Tx of the housing 2 detected by the above is compared with the second reference temperature Tb (cooling operation start temperature, for example, 75 degrees Celsius) at regular intervals (or always) (step 23). The second reference temperature Tb is lower than the first reference temperature Ta.

  Here, when the internal temperature Tx becomes equal to or lower than the second reference temperature Tb until the predetermined time ta elapses (when YES in step 23), the excessive temperature rise prevention control is terminated. On the other hand, the internal temperature Tx does not become the second reference temperature Tb or less during the predetermined time ta, and the predetermined time ta elapses after the start of the air blowing operation (NO in step 23, YES in step 24). ), The controller 5 confirms that an abnormal temperature rise has occurred (step 25), and ends the excessive temperature rise prevention control. In other words, if the internal temperature Tx does not decrease despite the air blowing for a certain period of time, it can not be said that the post-purge is not completed, but it is not the cause of the abnormal temperature rise. Is expected. Therefore, in this case, the excessive temperature rise prevention operation is terminated.

  When the excessive temperature rise prevention control is completed, the routine proceeds from step 2 to step 3 in FIG. When an abnormal temperature rise is confirmed by the excessive temperature rise prevention control (passed through step 25 in FIG. 6), a safety operation is performed (step 8) and the overheat status confirmation control is terminated. In this case (step 8), the safety operation is specifically a cooling operation. More specifically, the cooling operation is an operation for cooling the inside of the housing 2, and specifically, the inside of the housing 2 is cooled by operating the fan 4 at a higher rotational speed than the air blowing operation. .

  On the other hand, when the abnormal temperature rise is not confirmed by the excessive temperature rise prevention control (the process does not pass step 25 in FIG. 6), the process proceeds to step 4 and the safety confirmation control before ignition is performed. The safety confirmation control before ignition according to the present embodiment will be described in detail with reference to FIG.

  When the pre-ignition safety confirmation control is started, the internal temperature Tx of the housing 2 detected by the internal temperature detection thermistor 7 at that time is compared with a third reference temperature Tc (for example, 40 degrees Celsius) (step 31). ). The third reference temperature Tc is lower than the first reference temperature Tb described above. That is, the temperature decreases in the order of the first reference temperature Ta, the second reference temperature Tb, and the third reference temperature Tc.

  If the internal temperature Tx is equal to or lower than the third reference temperature Tc (YES in step 31), the ignition reference value X is set to the ignition reference value A1 (for example, 3 mV) (step 32). On the other hand, when the internal temperature Tx is higher than the third reference temperature Tc (NO in step 31), the ignition reference value X is set to the re-ignition reference value A2 (for example, 10.5 mV) (step 36). At this time, the re-ignition reference value A2 is larger than the ignition reference value A1. In other words, the standard (threshold) for ignition is lowered (specifically, the threshold is increased) to create an environment in which ignition is easy. That is, when the internal temperature Tx is high, only heat remains in the device, and there is no abnormality in the device, so that the ignition operation may be performed by the burner 17.

  When the value of the ignition reference value X is determined in step 32 or step 36, the process proceeds to step 33, and the voltage value Ax of the voltage generated by the thermocouple 18 at this time is compared with the determined ignition reference value X. Here, when the voltage value Ax is equal to or less than the ignition reference value X (in the case of YES at step 33), the control device 5 supplies gas to the burner 17 and operates the spark plug 19 to perform the ignition operation (step). 37). Then, the safety confirmation control before ignition ends.

  On the other hand, when the voltage value Ax is larger than the ignition reference value X (NO in step 33), the control device 5 does not operate until the predetermined time tb (for example, 60 seconds) elapses (step 34). The voltage value Ax generated by the pair 18 and the ignition reference value X are compared at regular time intervals (or always). In the meantime, if the voltage value Ax is equal to or less than the ignition reference value X, an ignition operation is performed (step 37), and the pre-ignition safety confirmation control is terminated.

  Here, when the voltage value Ax does not become the ignition reference value X or less even after the predetermined time tb (for example, 60 seconds) has elapsed, the control device 5 confirms that an abnormality has occurred (step 35), End the safety confirmation control before ignition. That is, when the temperature in the vicinity of the burner 17 does not show any signs of lowering even though the air is blown for a certain period of time, it cannot be said that the post-purge is not completed. It is expected that there will be. Therefore, also in this case, an error is generated and the pre-ignition safety confirmation control is terminated without performing the ignition operation and the heating operation.

  When the pre-ignition safety confirmation control is completed, the routine proceeds from step 4 to step 5 in FIG. And when abnormality is confirmed by the safety confirmation control before ignition (step 35 of FIG. 7 is passed), that is, in the case of YES in step 5, an operation for safety is performed (step 9) and the overheating state Confirmation control ends. In this case (step 9), the operation for safety specifically ends when an error occurs in the operation panel 9 without performing the ignition operation and the heating operation.

  When the ignition operation is performed in the safety confirmation control before ignition (passed through step 37 in FIG. 7), the heating operation is performed (step 6), and the overheat condition confirmation control is ended.

  In the above-described embodiment, the blowing operation performed at the start of the overheating state confirmation control is continued until the ignition operation is performed or the safety operation is performed.

  In the above-described embodiment, two controls, the excessive temperature rise prevention control and the pre-ignition safety confirmation control, are performed in the overheating state confirmation control, but the overheating state confirmation control of the present invention is not limited to this. For example, the configuration may be such that only the excessive temperature rise prevention control is performed and the ignition operation is performed after the control.

  In the above-described embodiment, an example in which the safety operation (cooling operation) is performed in step 8 and then finished without performing the heating operation has been described, but the overheating state confirmation control of the present invention is not limited to this. For example, the normal heating operation is started when it is confirmed by the internal temperature detection thermistor 7 and the control device 5 that the internal temperature of the hot air heating device has decreased after the safety operation (cooling operation) is completed. It doesn't matter.

  Moreover, although the example which employ | adopted the non-volatile memory | storage means 25 as a memory | storage means was shown in above-described embodiment, the warm air heating apparatus of this invention is not restricted to this. For example, a volatile memory may be adopted as the storage unit. Even if the power supply is independent from the normal power supply system (power plug, etc.) for supplying power to each device such as the control device and the blower, and the volatile memory is connected to the power supply as a storage means Good. That is, it is only necessary that the stored information can be held when the power supply by the normal power supply system is stopped.

  Furthermore, in the above-described embodiment, an example in which the operation switch 8 is arranged on the operation panel 9 provided on the top surface of the casing 2 has been described, but the hot air heating device of the present invention is not limited to this. The operation panel may be provided in any part of the housing. Further, various input devices such as operation switches may be provided not only on the operation panel but also on an external remote controller.

  In the above-described embodiment, the example in which the thermocouple 18 in the combustion case 3 is the second temperature detection means has been described, but the hot air heating device of the present invention is not limited to this. For example, a thermistor may be employed as the second temperature detecting means and disposed outside the combustion case.

  In the embodiment described above, based on the result of comparing the internal temperature Tx of the housing 2 detected by the internal temperature detection thermistor 7 (first temperature detection means) and the third reference temperature Tc (for example, 40 degrees Celsius). Although an example in which the ignition reference value X is either the ignition reference value A1 or the re-ignition reference value A2 has been shown, the hot air heating apparatus of the present invention is not limited to this. For example, based on the temperature (value) detected by the thermocouple 18 (second temperature detection means) instead of the internal temperature detection thermistor 7 (first temperature detection means), the ignition reference value X is changed to the ignition reference value A1 or The configuration may be any one of the ignition reference values A2. That is, it is sufficient if the ignition reference value X can be selected based on the internal temperature rise state, and the internal temperature rise detection method is not limited at all.

  Furthermore, in the above-described embodiment, an example in which the present invention is applied to a so-called floor-mounted gas fan heater that is used by being placed on an indoor floor is shown. However, the hot air heating apparatus of the present invention is not limited thereto. It is not a thing. The present invention may be applied to a hot air heating apparatus that generates hot air by burning liquid fuel such as petroleum, not limited to burning gaseous fuel such as gas.

DESCRIPTION OF SYMBOLS 1 Hot air heating apparatus 4 Blower 5 Control apparatus 7 Thermistor for internal temperature detection (1st temperature detection means)
8 Operation switch 17 Burner 18 Thermocouple (second temperature detection means)
25 Nonvolatile storage means (storage means)

Claims (4)

A burner, a blower, an operation switch, storage means, and a control device;
Based on the input signal from the operation switch, it is possible to switch between heating operation start and heating operation stop,
When the heating operation is stopped, the blower is operated to perform the post purge.
The control device can write operation status information regarding the start and end of the post purge to the storage means,
When energization from the external power supply is stopped and then re-energized, and heating operation is started by a signal from the operation switch,
In the operation before re-energization, the controller determines whether or not energization is stopped between the start of post-purge and the end of post-purge. A first temperature detecting means for detecting the internal temperature of the hot air heater, and a second temperature detecting means for detecting the temperature of the burner or the vicinity of the burner,
With one of the conditions that the value detected by the second temperature detection means is below a predetermined ignition reference value, the burner is ignited.
When the energization is stopped between the start of the post purge and the end of the post purge, the first temperature detection means or the second temperature detection means is used when the burner is ignited after the air blowing operation. The warm air heating device according to claim 1, wherein the ignition reference value is set to a re-ignition reference value larger than the ignition reference value at the start of normal heating operation based on the temperature detected by the engine. The second temperature detection means is a burner sensor that generates a voltage corresponding to a temperature of a burner or a temperature near the burner, and the ignition reference value is a predetermined reference voltage value,
With one of the conditions that the voltage value of the voltage generated by the second temperature detecting means is below the ignition reference value, the burner is ignited.
When the energization is stopped between the start of the post purge and the end of the post purge, the first temperature detection means or the second temperature detection means is used when the burner is ignited after the air blowing operation. The warm air heating device according to claim 2, wherein the reference voltage value is set to a reignition reference value that is larger than the ignition reference value at the start of normal heating operation based on the temperature detected by.   When the energization is stopped between the start of the post purge and the end of the post purge, the air blowing operation is performed. After the air blowing operation is performed, the first temperature detecting means is set to a predetermined value. The hot air heating device according to claim 2 or 3, wherein the cooling operation is started on condition that the temperature reaches a cooling operation start temperature or more.

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