JPH11264614A - Combustion type fan forced heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion type fan forced heater which can continue the temperature control operation when it goes out during forced combustion operation after reignition by temperature control operation. SOLUTION: This heater is equipped with a combustor 4, a blow fan 3 which blows out hot air, a room temperature detection means 13, a room temperature setting means 28, an operation switch 27, a combustion control means 7 which performs temperature control operation during heating operation and performs forced combustion operation with the quantity of combustion smaller than the maximum quantity of combustion at the time of reignition by temperature control operation, and a combustion state detection means 20. This system is provided with a flame failure treatment means which detects flame failure and stops the forced combustion operation when the output level of the combustion state detection means 20 falls below the specified level during forced combustion operation, and performs reignition when the temperature of the room detected by a room temperature detection means 13 falls under the temperature control reignition temperature based on the set temperature of the room temperature setting means 28. A combustion control means 7 starts the forced, combustion operation with the maximum quantity of combustion at the time of reignition after detecting the flame failure during forced combustion operation. The said specified level is set to the output level higher than the abnormal flame failure level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a combustion type hot air heater such as a gas hot air heater.

[0002]

2. Description of the Related Art A combustor is accommodated in a main body case, such as a gas warm air heater, which is disposed indoors, and a combustion fan provided in the main body case draws room air into the main body case while burning the combustor. In a combustion-type hot-air heater that blows hot air heated by heat into a room, a room temperature is detected using a room temperature sensor, and the detected room temperature substantially matches a set room temperature set by a user or the like. The temperature control operation is performed as described above. In such a combustion type hot air heater, the temperature control operation controls the combustion amount of the combustor and the air volume of the blower fan, and furthermore, the room temperature rises above the set room temperature only by controlling the combustion volume and the air volume. In some cases, the fire extinguishing / reignition of the combustor is intermittently repeated (the fire extinguishing / reignition of the combustor is automatically repeated).

In this type of combustion type hot air heater, if an abnormal misfire occurs during the combustion operation of the combustor, the misfire is detected by abnormal misfire detection means and the combustor is stopped. Further, in order to stabilize the combustion of the combustor at an early stage and prevent a misfire from occurring, at the beginning of the start of the combustion operation of the combustor, a first predetermined period (for example, 1
(0 seconds), a fixed-quantity combustion operation for burning the combustor at its maximum combustion amount is performed. In this case, the first
Is determined so that combustion of the combustor can be reliably stabilized regardless of various operating environments of the combustor or variations in the type of fuel or the fuel component. Such quantitative combustion operation is performed not only at the time of ignition (at the start of heating operation) in accordance with the turning on of the operation switch of the hot air heater, but also at the time of re-ignition of the combustor in the temperature control control (at the time of combustion operation). At the time of resumption). Also, if fire extinguishing / reignition is frequently repeated by the temperature control, the user may feel uncomfortable due to ignition noise or the like. In some cases, a so-called temperature control operation in which the combustion amount is determined according to the difference between the two is forcibly performed for a second predetermined time (for example, 50 seconds) after the quantitative combustion operation. That is, in this case, the quantitative combustion operation for the first predetermined time from the start of ignition or the start of re-ignition, and the second combustion
For a predetermined time (for example, 6
For 0 second), the forced combustion operation for forcibly burning the combustor is performed.

In such a conventional combustion type hot air heater,
At the time of ignition (at the start of heating operation) according to the turning on of the operation switch of the hot air heater, since the room temperature is generally low, the combustion of the combustor is performed early by performing the above-mentioned forced combustion operation of the combustor. Not only stabilization, but also room temperature can be raised quickly. However, at the time of re-ignition of the combustor in the subsequent temperature control control operation (when restarting combustion), since the room temperature is already close to the set room temperature, the quantitative combustion operation of the maximum combustion amount is performed at that time. Thus, there is a problem that the room temperature easily rises excessively with respect to the set temperature within the predetermined period.

[0005] In order to solve the above-mentioned problem, the re-ignition of the combustor by the temperature control operation is performed by performing the fixed-quantity combustion operation with a combustion amount smaller than the maximum combustion amount. Can be considered.

However, if the combustion amount in the quantitative combustion operation is uniformly smaller than the maximum combustion amount at the time of reignition of the combustor by the temperature adjustment control operation, the temperature adjustment control operation in the forced combustion operation may be performed due to environmental conditions or the like. If the misfire is detected by the abnormal misfire detection means, it is determined that the apparatus itself is mechanically abnormal, the combustor itself is stopped, and the temperature control operation is continued. The inconvenience of not being able to do it occurs.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a combustion type temperature control system for repetitively extinguishing and reigniting a combustor in a temperature control operation for resolving such inconvenience and making a room temperature substantially coincide with a set temperature. In a wind heater, a combustion-type warm air that can continue the temperature control operation without stopping the combustor itself even when a misfire occurs during the forced combustion operation after re-ignition by the temperature control operation. It is intended to provide a heater.

[0008]

In order to achieve the above object, a combustion type hot air heater according to the present invention comprises a combustor housed in a main body case and a room air drawn into the main body case. A blower fan that blows out hot air heated by the combustion heat of the combustor from the main body case, a room temperature detecting unit that detects a room temperature, a room temperature setting unit that sets a room temperature, and an instruction to start and stop a heating operation. An operating switch for igniting and extinguishing the combustor, and a room temperature set by the room temperature setting unit so that the detected room temperature detected by the room temperature detecting unit during the heating operation substantially matches the set temperature. Extinguishing the combustor when the temperature exceeds the temperature regulation extinguishing temperature based on the temperature control, and reignites the combustor when the detected temperature falls below the temperature regulation reignition temperature based on the room temperature set by the room temperature setting means. Warm Combustion control means for performing a control operation and performing a forced combustion operation for burning the combustor with a combustion amount smaller than a maximum combustion amount of the combustor for a predetermined time after re-ignition of the combustor by the temperature control control operation; When,
Combustion state detection means for detecting a combustion state of the combustor and outputting a signal of an output level corresponding to the combustion state, wherein the combustion state detection is performed during the forced combustion operation. A misfire is detected when the output of the means falls below a predetermined level, the forced combustion operation is stopped, and when the detected room temperature detected by the room temperature detecting means falls below the temperature control re-ignition temperature, A misfire treatment means for reigniting the combustor is provided.

According to the combustion type hot air heater of the present invention, the forced combustion operation is performed for a predetermined time after the reignition of the combustor by the temperature control operation. Since combustion is started at a combustion amount smaller than the maximum combustion amount of the combustor, for example, a medium combustion amount between the maximum combustion amount and the minimum combustion amount, a misfire may occur due to environmental conditions or the like. However, this misfire often depends on the environmental conditions as described above, and it is often unnecessary to abnormally stop the combustor.

Therefore, the present invention provides the misfire processing means, wherein the misfire detection means sets the output level of the combustion state detection means to a predetermined level or less during the forced combustion operation at the time of reignition by the temperature control control operation. When it detects that
The misfire processing means determines that this is a misfire due to the environmental conditions or the like, stops the forced combustion operation, and detects a room temperature detected by the room temperature detection means at a temperature at which reignition in the temperature control operation is to be started. When the temperature falls below the temperature regulation reignition temperature, the combustor is reignited in the same manner as in the temperature regulation control operation.

Therefore, according to the present invention, even if a misfire occurs during the forced combustion operation after re-ignition by the temperature control operation, the combustor is stopped as an abnormal misfire due to a mechanical abnormality of the device itself. Instead, the combustor can be reignited and the temperature control operation can be continued.

Also, in the combustion type hot air heater according to the present invention, the combustion control means may start the forced combustion operation at a maximum combustion amount of the combustor when the misfire treatment means reignites the combustor. It is characterized by.

When the misfire is detected by the misfire treatment means, there is a cause of misfire due to environmental conditions or the like. After the misfire treatment means stops the forced combustion operation, the misfire treatment is performed in the same manner as in the temperature control operation. When re-igniting the combustor, the cause of the misfire may not be eliminated yet.

Therefore, according to the present invention, when the misfire treatment means detects the misfire and performs the forced combustion operation after reigniting the combustor, the combustion amount is set as the maximum combustion amount of the combustor. By starting the combustion, the combustion of the combustor can be reliably stabilized.

Further, the combustion type hot air heater of the present invention detects the abnormal misfire when the output level of the combustion state detecting means falls below the abnormal misfire level during the combustion operation of the combustor. An abnormal misfire processing means for stopping the operation of the vessel, wherein the predetermined misfire level is an output level higher than the abnormal misfire level.

The combustion-type hot-air heater of the present invention includes the abnormal misfire processing means, so that the abnormal misfire can be detected and the combustor can be stopped during the combustion operation of the combustor. However, in this case, even when a misfire occurs due to the environmental conditions or the like during the forced combustion operation, there is a possibility that the abnormal misfire processing means operates to stop the operation of the combustor. Therefore, according to the present invention, by setting the predetermined level for detecting misfire due to the environmental condition or the like to a level higher than the abnormal misfire level, the misfire treatment means is given priority during the forced combustion operation. To stop the operation of the combustor due to the operation of the abnormal misfire treatment means.

[0017]

Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is a system configuration diagram of the warm air heater of the present embodiment,
FIG. 2 is a block diagram showing the configuration of the control unit shown in FIG. 1,
3 to 5 are flowcharts showing the operation of the hot air heater shown in FIG.

Referring to FIG. 1, the hot air heater of the present embodiment is, for example, a gas fan heater, and includes a duct 2, a blower fan 3, a gas burner (combustor) 4 in a main body case 1 disposed indoors. , A duct 5, a gas supply pipe 6, and a control unit 7 (combustion control means).

The duct 2 constitutes an air passage for hot air. The air inlet 8 for taking in the room air is opened at the back of the main body case 1, and the hot air outlet is provided at the lower front part of the main body case 1. 9 is open. In order to prevent dust and dirt from flowing into the duct 2, the air filter 1
0 is detachably attached. A movable louver 11 for adjusting the opening degree is attached to the outlet 9,
Gad motor 1 for driving this movable louver 11
2 are provided. In addition, the intake port 8 inside the duct 2
A room temperature sensor 13 (room temperature detecting means) constituted by a thermistor facing the air inlet 8 is attached to a nearby location, and the room temperature sensor 13 outputs a signal corresponding to the room temperature to the control unit 7.

The blower fan 3 has a fan motor 14 whose number of revolutions changes in proportion to the energizing current, and rotating blades 15 arranged in the duct 2 facing the air outlet 9 and driven to rotate by the fan motor 14. Then, the indoor air s is sucked into the duct 2 from the intake port 8 by the rotation of the rotary blade 15. Then, the sucked room air s is mixed with the combustion exhaust gas h of the gas burner 4 incorporated in the duct 2 and blown out as warm air m from the outlet 9 into the room. This blower fan 3
A rotation speed sensor 16 constituted by a Hall element or the like for detecting the rotation speed is provided. The rotation speed sensor 16 outputs a signal corresponding to the rotation speed of the fan motor 14 to the control unit 7.
Output to

Gas burner 4 incorporated in duct 2
Has an ignition electrode 19 for arranging a combustion plate 18 in a combustion cylinder 17 and igniting a mixture of combustion air and fuel gas.
Is disposed downstream of the combustion plate 18. The combustion cylinder 17 of the gas burner 4 is disposed in the duct 2, and the combustion exhaust h is discharged from the combustion cylinder 17 into the duct 2. Further, a thermocouple 20 (combustion state detecting means) for detecting the presence or absence of a combustion flame is disposed downstream of the combustion plate 18, and the thermocouple 20 is activated when exposed to the combustion flame of the gas burner 4. Electric power is generated and output to the control unit 7 as the combustion state of the gas burner 4.

The duct 5 is a passage for supplying the indoor air s (combustion air) and the fuel gas to the gas burner 4, and communicates with the inside of the combustion cylinder 17 of the gas burner 4 and the duct 2
Is incorporated in the main body case 1 and the main body case 1
Has an air intake port 21 for room air s which is open at the back of the vehicle. A nozzle 22 attached to the tip of the gas supply pipe 6 is provided at a location on the gas burner 4 side of the duct 5. The indoor air s is sucked into the duct 5 from the intake port 21 by the rotation of the blower fan 3, and the sucked indoor air s is mixed with the fuel gas ejected from the nozzle 22 of the gas supply pipe 6. The mixture is supplied to the gas burner 4. The air inlet 21 is covered by the air filter 10 together with the air inlet 8 of the duct 2.

The gas supply pipe 6 is provided with electromagnetic valves 24 and 25 and an electromagnetic proportional valve 26 in this order from the upstream side. The solenoid valves 24 and 25 are opened by energization, and shut off the passage of fuel gas in a closed state where energization is stopped. The electromagnetic proportional valve 26 is a valve whose opening increases with the magnitude of the energizing current, and the energizing current is proportional to the amount of gas supplied to the gas burner 4.

An operation switch 2 is provided on the outer surface of the main body case 1.
7, a room temperature setting switch 28 and a filter lamp 29 are provided. The operation switch 27 has its ON / OFF
The operation instructs the control unit 7 to start or end the heating operation. The room temperature setting switch 28 is an operation switch for setting the room temperature, and instructs the control unit 7 by increasing or decreasing the set temperature T by, for example, 1 ° C. by a predetermined operation. The filter lamp 29 is controlled by the power supply control of the control unit 7 when the air volume at the time of the rotation operation of the blower fan 3 becomes smaller to some extent as compared with the normal operation, such as when the clogging of the air filter 10 is progressing. The air filter is turned on, and the user is notified of the necessity of cleaning the air filter 10 by the lighting.

Next, referring to FIG.
Is configured using a microcomputer or the like. The major functional components can be roughly classified into a combustion control unit 30, a fan control unit 31, an abnormal misfire detection unit 32, a forced combustion misfire detection unit 33, and Timers 34, 35, 36, 3
7, 38 are provided. The misfire processing means of the present invention includes a forced combustion misfire detection unit 33, a combustion control unit 30, and a fan control unit 31, and the abnormal misfire processing means of the present invention includes an abnormal misfire detection unit 32, a combustion control unit 30 and a fan control unit 31.

The combustion control unit 30 is provided with instruction signals of the operation switch 27 and the room temperature setting switch 28 and the room temperature sensor 1
Based on the detection signals of the thermocouple 3 and the thermocouple 20, the ignition, extinguishing, and adjustment of the combustion amount of the gas burner 4 (adjustment of the supply amount of the fuel gas).
For example, combustion control of the gas burner 4 is performed. In this case, in the present embodiment, during the combustion operation including the ignition operation of the gas burner 4, the combustion control unit 30 adjusts the combustion amount (fuel gas supply amount) of the gas burner 4 to the 1st to 12th speed (the 12th speed is the maximum combustion). (Corresponding to the amount).

The fan control unit 31 is provided with instruction signals for the operation switch 27 and the room temperature setting sensor 28 and the room temperature sensor 1
3. Based on the detection signals of the rotation speed sensor 16 and the thermocouple 20, the fan motor 14 is energized to control the rotation speed of the blower fan 3, thereby controlling the rotation of the blower fan 3 including the combustion air to the gas burner 4. Control the air volume. During the combustion operation including the ignition operation of the gas burner 4, the fan control unit 31 controls the blowing fan 3 according to the combustion amount of the gas burner 4.
Can be set in 12 stages of 1 to 12 speeds (12 speeds correspond to the maximum rotation speed of the blower fan 3 corresponding to the maximum combustion amount).

The combustion amount (fuel gas supply amount) of the gas burner 4 at each speed described above and the blowing fan 3 corresponding thereto
Is determined in advance. The control by the combustion control unit 30 and the fan control unit 31 is as follows.
The details are performed according to a predetermined sequence described later.

The abnormal misfire detection unit 32 monitors the output of the thermocouple 20 during the combustion operation including the ignition / reignition operation of the gas burner 4, and when the output becomes lower than the abnormal misfire level, the gas burner 4 It is determined that a misfire has occurred, and the combustion control unit 30 and the fan control unit 31 are instructed to stop the gas burner 4 abnormally.

The forced combustion misfire detection unit 33 monitors the output of the thermocouple 20 during the forced combustion operation of the gas burner 4 corresponding to the reignition by the temperature control operation, and the output becomes lower than a predetermined forced combustion misfire level. When it is determined that the gas burner 4 has misfired, the combustion control unit 30 and the fan control unit 3
1 is instructed to stop the gas burner 4 and re-ignition by the temperature control operation. Since the forced combustion misfire level is set to a value higher than the abnormal misfire level, the forced combustion misfire detection unit 33 can operate prior to the abnormal misfire detection unit 32 during the forced combustion operation.

In a pre-purge prior to the start of the combustion operation of the gas burner 4, the timer 34 controls the combustion control unit 30 and the fan control unit 31 based on the output of the rotation speed sensor 16.
Time for determining whether the rotation of the blower fan 3 is equal to or higher than the minimum rotation level (for example, 1
0 seconds). Further, the timer 34 is a gas burner 4
After the ignition / reignition of the engine is started at a predetermined combustion amount (for example, 10 minutes from the start of the ignition / reignition).
Seconds).

The timer 35 sets a time (for example, for the ignition / reignition operation) for the abnormal misfire detection unit 32 to judge whether the gas burner 4 is ignited or non-ignited based on the output of the thermocouple 20 when the gas burner 4 is ignited / reignited. (30 seconds from the start).

In an initial state prior to the start of the combustion operation of the gas burner 4, the timer 36 controls the combustion control unit 30 and the fan control unit 31 based on the output of the thermocouple 20,
A time for determining the normal / abnormal state of 0 (for example, 50 seconds after the operation switch 27 is turned on) is measured.

The timer 37 measures the time (for example, 60 seconds) for performing the forced combustion operation after the ignition / reignition of the gas burner 4.

The timer 38 measures the time (for example, 8 minutes) from the stop of the combustion operation due to the temperature control operation to the restart of the combustion operation of the gas burner 4.

Hereinafter, these timers 34, 35, 36,
37 and 38 are referred to as a 10-second timer 34, a 30-second timer 35, a 50-second timer 36, a 60-second timer 37, and an 8-minute timer 38, respectively.

Next, a first mode of operation of the gas hot air heater according to the present embodiment will be described with reference to FIGS.

First, referring to FIG. 3, when the user turns on the operation switch 27 to perform the heating operation (STE).
P1), and accordingly, the combustion control unit 30 of the control unit 7
First, the temperature control flag for identifying that the temperature control operation is being performed and the misfire flag for identifying that a misfire has occurred during the forced combustion operation corresponding to the reignition by the temperature control operation are both turned off. (Step 2). Next, the combustion control unit 30 operates the 50-second timer 36 (STEP 3).
At the same time, the output of the thermocouple 20 is compared with a predetermined initial check level (for example, 10 mV) (STEP 4). If the 50-second timer 36 times out before the output of the thermocouple 20 becomes equal to or lower than the initial check level (STEP 5), the output of the thermocouple 20 is stopped abnormally as an error. On the other hand, if the output of the thermocouple 20 becomes equal to or less than the initial check level in STEP 3 before the time of the 50-second timer 36 expires, it is determined that the output of the thermocouple 20 is normal, and the process proceeds to STEP 6.

In STEP 6, the fan control unit 31 controls the energization of the fan motor 14 so that the blower fan 3 is operated at a predetermined rotation speed (for example, a rotation speed corresponding to the 12th speed) for a certain period of time. Pre-purge is performed.
At the same time, the combustion control unit 30 activates the 10-second timer 34, and based on the output of the rotation speed sensor 16,
It is determined whether or not the rotation speed is normal (STEP 4).
7). Then, the rotation of the blower fan 3 indicated by the output of the rotation speed sensor 16 reaches the minimum rotation level (for example, 6 rpm).
If the time of the 10-second timer 34 has expired (STEP 8) before the time does not reach m) or more, the rotation of the blower fan 3 is abnormally stopped as an error. On the other hand, a 10-second timer 34
If the rotation of the blower fan 3 becomes equal to or higher than the minimum rotation level in STEP 6 before the time is up, it is determined that the rotation of the blower fan 3 is normal, and the process proceeds to STEP 9.

In STEP 9 after the prepurge, the combustion control unit 30 energizes the solenoid valves 24 and 25 to open them, and controls the energization of the solenoid proportional valve 26 so that the fuel gas is equivalent to the eighth speed (medium). (Amount of combustion) to the gas burner 4, and furthermore, the ignition electrode 19 is energized so as to generate a spark discharge for a predetermined time. At the same time, the fan control unit 31 controls the energization of the fan motor 14 so as to continue to operate the blower fan 3 from the pre-purge, so that the number of revolutions of the fan motor 14 is equivalent to the eighth speed (medium rotation).

Next, the combustion control unit 30 sets a 30-second timer
Is activated (STEP 10), and the abnormal misfire detection unit 32 compares the output of the thermocouple 20 with an abnormal misfire level (for example, 14 mV) (STEP 11). Then, the abnormal misfire detection unit 3
If the 30-second timer 35 times out (STEP 12) before detecting that the output of the thermocouple 20 has become equal to or higher than the abnormal misfire level, an error is determined as a misfire (non-ignition) by the ignition electrode 19. Stop. on the other hand,
Before the 30-second timer 35 expires, the STE
If the output of the thermocouple 20 becomes equal to or higher than the abnormal misfire level at P11, it is determined that the ignition has been performed well and the ignition electrode 1
Then, the energization to 9 is stopped (STEP 13), the combustion operation is started, and the process proceeds to STEP 14.

In STEP 14, the temperature control flag is turned on.
It is determined whether the state is the state or not. When the ignition is performed by the ON operation of the operation switch 27, since the temperature control flag is OFF in STEP2, the process proceeds to STEP15 in FIG. Control unit 3
In order to stabilize the combustion of the gas burner 4 at an early stage and to quickly raise the room temperature, 1 performs a fixed amount combustion operation for a predetermined time at a maximum combustion amount corresponding to the 12th speed. Here, during the initial period of the start of the combustion operation of the combustor, the combustion of the combustor can be reliably performed at an early stage regardless of various operating environments of the combustor or variations in fuel type or fuel component. (For example, 10 seconds).

When the quantitative combustion operation is started in STEP 15, first, the combustion control unit 30 controls the energization of the electromagnetic proportional valve 26 so that the fuel gas supplied to the gas burner 4 becomes equivalent to the 12th speed (maximum combustion amount). At the same time, the fan control unit 31 controls the energization of the fan motor 14 so that the rotation speed of the blower fan 3 becomes equivalent to the 12th speed (maximum rotation speed). Next, the combustion control unit 30 controls the 10-second timers 34 and 6
The zero-second timer 37 is operated (STEP 16), and the 10-second timer 34 starts measuring the duration of the quantitative combustion operation based on the maximum combustion amount. The 60-second timer 37 controls the quantitative combustion operation and the first temperature control described later. Start timing of the total duration of the control operation.

During the quantitative combustion operation, the abnormal misfire detection unit 32
Compares the output of thermocouple 20 with the abnormal misfire level (STE
P17) Upon detecting that the output of the thermocouple 20 has fallen below the abnormal misfire level, some mechanical abnormality has occurred in the device itself, and it is determined that abnormal misfire has occurred, and an error is stopped. On the other hand, if the 10-second timer 34 times out before the abnormal misfire detection unit 32 detects the abnormal misfire (S
(TEP18), the quantitative combustion operation ends, and the temperature control operation starts (STEP19).

As described above, after the fixed amount operation is completed, the temperature control operation is started. In this embodiment, the ignition and re-ignition of the gas burner 4 is prevented in order to prevent the fire from being frequently repeated. A predetermined time (for example, 6
(0 second), the gas burner 4 is not extinguished (stopped combustion) by the temperature control operation. That is, in the temperature control operation of the present embodiment, the room temperature t detected by the room temperature sensor 13 substantially coincides with the set temperature T set by the room temperature setting switch 28 until the predetermined time elapses from the start of ignition / reignition. The combustion amount (fuel gas supply amount) of the gas burner 4 and the air volume (rotation speed) of the blower fan 3 are controlled as described above. However, even when the room temperature t exceeds the temperature regulation and extinguishing temperature based on the set temperature T, the gas burner 4 is extinguished. The first temperature control operation is not performed, and the combustion amount of the gas burner 4 and the air volume of the blower fan 3 are controlled so that the room temperature t after the lapse of the predetermined time substantially matches the set temperature T, and the room temperature t is based on the set temperature T. This is distinguished from the second temperature control operation in which the gas burner 4 extinguishes the fire when the temperature exceeds the temperature control fire extinguishing temperature. The combination of the quantitative combustion operation and the first temperature control operation corresponds to the forced combustion operation of the present invention.

In the first temperature control operation, the combustion control unit 3
0 and the fan control unit 31 determine the combustion amount of the gas burner 4 and the fan 3 so that the room temperature t substantially matches the set temperature T.
Of the electromagnetic proportional valve 26 and the fan motor 14 so that the air volume of
Is controlled (STEP 20). During the first temperature control operation, the abnormal misfire detection unit 32 compares the output of the thermocouple 20 with the abnormal misfire level (STEP 21), and when it detects that the output of the thermocouple 20 has fallen below the abnormal misfire level, If any mechanical abnormality occurs in the device itself, it is determined that an abnormal misfire has occurred, and the device stops with an error. On the other hand, the abnormal misfire detection unit 3
When the timer 37 has timed out before the abnormal misfire has been detected by the control unit 2 (STEP 22), the first temperature control operation ends, and the process shifts to the second temperature control operation.

In the second temperature control operation, the combustion control unit 30 and the fan control unit 31 continue operating from the first temperature control operation and operate the gas burner 4 so that the room temperature t substantially matches the set temperature T. The combustion amount and the air volume of the blower fan 3 are each set to 1
The electromagnetic proportional valve 26 and the fan motor 14 are controlled so as to gradually decrease from the second speed to the first speed. Then, during the second temperature control operation, the abnormal misfire detection unit 32 compares the output of the thermocouple 20 with the abnormal misfire level (STEP 2).
3) When it is detected that the output of the thermocouple 20 has fallen below the abnormal misfire level, some mechanical abnormality has occurred in the device itself, and it is determined that abnormal misfire has occurred, and an error is stopped. On the other hand, while the abnormal misfire detection unit 32 does not detect the abnormal misfire, the room temperature t detected by the room temperature sensor 13 exceeds the set temperature T set by the room temperature setting switch 28 at a predetermined temperature control and extinguishing temperature (for example, T + 1 ° C.). ) (STEP 24), the combustion control unit 30 sets the electromagnetic proportional valve 2
It is determined that the room temperature tends to be excessively increased only by controlling the temperature of the fan 6 and the fan motor 14, and the combustion operation of the gas burner 4 is stopped (STEP 25). At this time,
Since the stop of the combustion operation is based on the second temperature control operation and presupposes that the gas burner 4 is re-ignited under a predetermined condition, the combustion control unit 30 identifies that the temperature control operation is being performed. The eight minute timer 37 is activated at the same time as turning on the temperature control flag.

When the combustion operation is stopped by the second temperature control operation, the combustion control unit 30 stops the energization control for the electromagnetic proportional valve 26 and the electromagnetic valve 2
The energization to 4, 25 is stopped and the valve is closed. At the same time, the fan control unit 31 controls the energization of the fan motor 14 so as to operate the blower fan 3 at a predetermined rotation speed (for example, a weak rotation corresponding to the first speed) for a certain period of time.
5 and then the power supply to the fan motor 14 is stopped to stop the blower fan 3 (ST
EP26).

When the combustion operation is stopped as described above, the room temperature t detected by the room temperature sensor 13 gradually decreases. Therefore, the combustion control unit 30 monitors the room temperature t, and before the 8-minute timer 37 times out, the room temperature sensor 13
When the room temperature t detected at the time falls below the set temperature T (temperature control re-ignition temperature) set by the room temperature setting switch 28 (ST
In EP27), the flow returns to STEP3 in FIG. Also,
Even if the room temperature t detected by the room temperature sensor 13 does not fall below the set temperature T set by the room temperature setting switch 28, when the eight minute timer 37 times out (STEP 28), the process returns to STEP 3 in FIG.

As a result, the operations of STEP 3 to STEP 13 are repeated, and the gas burner 4 is re-ignited. When the gas burner 4 is re-ignited by the second temperature control operation, the temperature control flag is turned ON in STEP 25, and in STEP 14, the process proceeds to STEP 29 in FIG.

In STEP 29, the misfire flag is turned on.
It is determined whether or not the state is a state. At the first time of the temperature control control operation, since the misfire flag is kept OFF in STEP2, the process proceeds to STEP30 and proceeds to STEP3.
When the value is 0, the combustion control unit 30 and the fan control unit 31 perform the fixed amount combustion operation for a predetermined time with the combustion amount smaller than the maximum combustion amount. By performing the fixed-quantity combustion operation after re-ignition by the second temperature control operation with a combustion amount smaller than the maximum combustion amount as described above, an excessive rise in room temperature can be avoided.

When the quantitative combustion operation is started in STEP 30, the combustion control unit 30 first controls the energization of the electromagnetic proportional valve 26, and the fuel gas is supplied to the gas burner 4 at an eighth speed (medium combustion amount). And at the same time, the fan control unit 31
Controls the energization of the fan motor 14 so that the rotation speed of the blower fan 3 becomes equivalent to the eighth speed (medium rotation speed).

Next, the combustion control unit 30 sets the 10-second timer
And the 60-second timer 37 is activated (STEP 31).
The 0 second timer 34 starts measuring the duration of the quantitative combustion operation based on the medium combustion amount, and the 60 second timer 37
As a result, the measurement of the total duration of the fixed combustion operation and the subsequent first temperature control operation, that is, the duration of the forced combustion operation of the present invention, is started.

During the quantitative combustion operation, the forced combustion misfire detection section 33 compares the output of the thermocouple 20 with the forced combustion misfire level (for example, 18 mV) (STEP 32), and makes the output of the thermocouple 20 fall below the forced combustion misfire level. When it is detected that the misfire has occurred, it is determined that a misfire has occurred due to environmental conditions or the like irrespective of the mechanical abnormality of the apparatus itself. Further, the forced combustion misfire detection unit 3
If the 10-second timer 36 times out before Step 3 detects the misfire (STEP 33), the quantitative combustion operation is terminated and the temperature control operation is started (STEP 34).

In the temperature control operation of the present embodiment, the first temperature control operation and the second temperature control operation are distinguished as described above. First, the first temperature control operation is performed.

In the first temperature control operation after the re-ignition, the combustion control unit 30 and the fan control unit 31 determine the combustion amount of the gas burner 4 and the fan 3 so that the room temperature t substantially matches the set temperature T. The electromagnetic proportional valve 26 and the fan motor 14 are controlled so that the air volume is gradually decreased from the eighth speed to the first speed (STEP 35). During the first temperature control operation, the forced combustion misfire detection unit 33 compares the output of the thermocouple 20 with the forced combustion misfire level (STEP 36), and determines that the output of the thermocouple 20 has fallen below the forced combustion misfire level. If detected, it is determined that a misfire has occurred due to environmental conditions or the like, regardless of the mechanical abnormality of the device itself. If the 60-second timer 37 times out before the forced combustion misfire detection unit 33 detects the misfire (STEP 37), the first
The temperature control operation ends, and the process proceeds to the second temperature control operation. The operations in STEPS 23 to 28 in FIG. 4 are repeated.

When the misfire occurs in STEP 32 or STEP 36, the output of the thermocouple 20 gradually decreases from a normal combustion state. In the present embodiment, the forced combustion misfire level is higher than the abnormal misfire level. Since it is set to the level, first, the forced combustion misfire level is reached, and the forced combustion misfire detection unit 32 operates preferentially.

If the forced combustion misfire is detected by the forced combustion misfire detection section 33 in STEP 32 or STEP 36, the combustion control means 30 turns on the misfire flag (STEP 38), and proceeds to STEP 25 in FIG. As a result, after the combustion stop operation by the second temperature regulation control operation is performed in STEP25 to STEP28,
3 and the operations of STEP3 to STEP13 are repeated, and the gas burner 4 is re-ignited. At the time of this reignition,
Since the temperature control flag is ON, the process proceeds to STEP 29 in FIG. 5 in STEP 14, and in STEP 29, the process proceeds to STEP 29.
Since the misfire flag has been turned ON at step 38,
F (STEP 39), and the flow proceeds to STEP 15 in FIG. In this case, since the forced combustion misfire has been detected in the previous forced combustion operation and the cause of the misfire may not be eliminated yet, the combustion control unit 30 and the fan control unit 31 correspond to the 12th speed in STEP15. The fixed amount combustion operation is performed for a predetermined time at the maximum combustion amount. And STEP16 ~
The operation of STEP 28 is repeated.

When the re-ignition is performed by the second temperature control operation after performing the quantitative combustion operation of the maximum combustion amount,
Since the misfire flag has been turned off in step 39, the process proceeds to step 30 again in step 29 of FIG. 5, and the quantitative combustion operation based on the medium combustion amount is performed, whereby an excessive rise in room temperature due to the forced combustion operation can be avoided.

The above-mentioned STEP 32 or STEP 3
When the forced combustion misfire is detected by the forced combustion misfire detection unit 33 in step 6, if the cause of the misfire is an abnormality of the apparatus, the combustion stop operation by the second temperature control control operation in STEP25 to STEP28 of FIG. Then, STEP3 to S in FIG.
When re-igniting the gas burner 4 in STEP 13,
No ignition is confirmed in 11 to 12, and an error is stopped.

In the present embodiment, when the forced combustion misfire is detected, the quantitative combustion operation is performed at the maximum combustion amount at the time of subsequent reignition.
The quantitative combustion operation may be performed with the medium combustion amount as in ep 29 to 33. In this case, step 38 is omitted, and the misfire flag is not turned on. Further, when the forced combustion misfire is detected, the quantitative combustion operation may be always performed with the maximum combustion amount at the time of subsequent reignition.

In this embodiment, the fixed combustion operation and the first temperature control operation are described as the forced combustion operation. However, only the fixed combustion operation may be the forced combustion operation. In this case, there is no distinction between the first temperature control operation and the second temperature control operation in the temperature control operation, and only the mode of the second temperature control operation of the present embodiment is performed as the temperature control operation.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a hot air heater according to an embodiment.

FIG. 2 is a block diagram showing a configuration of a control unit shown in FIG.

FIG. 3 is a flowchart showing the operation of the hot air heater shown in FIG. 1;

FIG. 4 is a flowchart showing the operation of the hot air heater shown in FIG. 1;

FIG. 5 is a flowchart showing the operation of the warm air heater shown in FIG. 1;

[Explanation of symbols]

1 ... body case, 3 ... blower fan, 4 ... combustor,
7: combustion control means, 13: room temperature detection means, 20: combustion state detection means, 27: operation switch, 28: room temperature setting means, 30, 31, 32: abnormal misfire treatment means, 3
0, 31, 33: misfire treatment means.

Claims (3)

[Claims] 1. A combustor housed in a main body case, a blower fan for blowing hot air generated by heating by combustion heat of the combustor from the main body case while sucking room air into the main body case, A room temperature detecting means for detecting a room temperature, a room temperature setting means for setting a room temperature, an operation switch for instructing operation / stop of a heating operation to ignite and extinguish the combustor, and the room temperature detecting means during a heating operation. In order to make the detected room temperature substantially coincide with the set temperature, the combustor is extinguished when the detected temperature exceeds a temperature control extinguishing temperature based on the room temperature set by the room temperature setting means, and the detected temperature becomes Performing a temperature control operation for reigniting the combustor when the temperature falls below a temperature control reignition temperature based on the room temperature set by the room temperature setting means, and starting from the reignition of the combustor by the temperature control operation. Time is combustion control means for performing a forced combustion operation for burning the combustor with a combustion amount smaller than the maximum combustion amount of the combustor, and detecting a combustion state of the combustor and setting an output level corresponding to the combustion state. A combustion state detecting means for outputting a signal, wherein the combustion state detecting means detects misfire when the output of the combustion state detecting means falls below a predetermined level during the forced combustion operation. Combustion characterized by providing a misfire treatment means for stopping the forced combustion operation and reigniting the combustor when the detected room temperature detected by the room temperature detection means falls below the temperature control reignition temperature. Hot air heater. 2. The combustion control means starts the forced combustion operation at the maximum combustion amount of the combustor when the misfire treatment means reignites the combustor.
The combustion-type hot air heater described. 3. An abnormal misfire processing means for detecting an abnormal misfire when the output level of the combustion state detecting means falls below an abnormal misfire level during the combustion operation of the combustor and stopping the operation of the combustor. The combustion type hot air heater according to claim 1 or 2, wherein the predetermined misfire level is an output level higher than the abnormal misfire level.