JP3345216B2 - Hot air heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot air heater such as a gas fan heater.

[0002]

2. Description of the Related Art For example, a hot air heater such as a gas fan heater includes a burner and a convection fan provided in a main body case disposed in a room. The convection fan causes convection of room air and the convection of the room air. It is generally known that room air is heated by combustion heat of a burner in the process.
In addition, this type of hot air heater includes a room temperature sensor, and controls a burner combustion amount such that a room temperature detected by the room temperature sensor matches a target room temperature set by a user or the like. For example, when the detected room temperature becomes higher than the target room temperature only by controlling the combustion amount of the burner, the combustion of the burner is performed intermittently, whereby the temperature is controlled so that the detected room temperature matches the target room temperature. A device that performs control is known.

In this type of hot air heater, the burner combustion and the operation of the convection fan are started by turning on an operation switch provided in a main body case or the like. When the operation switch is turned off, the burner combustion is stopped. Although it is stopped immediately, in order to prevent overheating of the main body case and the like due to the residual heat of the combustion hot air before the burner is stopped, the convection fan is operated continuously for an appropriate time after the burner is stopped,
A so-called post purge is performed. In this case, the time of the post-purge and the rotation speed of the convection fan at that time are generally set to a predetermined fixed time and a fixed rotation speed. However, the higher the combustion amount immediately before the burner is stopped, the higher the post-purge. It takes time to release the residual heat, and if the post-purging time is increased unnecessarily or the rotation speed of the convection fan is increased, the user may be given a feeling of cool air. For this reason, the combustion state immediately before the burner stops,
Post-purge time according to the internal temperature of the body case, etc.
Alternatively, a device for appropriately setting the rotation speed of the convection fan at that time has also been proposed by the present applicant (see, for example, JP-A-1-150748, JP-A-5-296571, and JP-A-1-256755). .

[0004] Such post-purging is also performed in a case where the combustion of the burner is temporarily stopped during the above-mentioned temperature control.

[0005] However, in the conventional hot air heater, the case where the combustion of the burner is temporarily stopped during the temperature control and the case where the combustion of the burner is stopped by operating the operation switch are the same. It has been found by the inventors of the present application that the following inconvenience occurs because the post-purge is performed.

That is, when the burner combustion is stopped by operating the operation switch, the user intends to stop the operation of the hot air heater, and the post-purge by the convection fan is immediately terminated. It is desirable to do.

However, if the post-purge accompanying the stoppage of the burner is terminated earlier, the combustion of the burner is automatically stopped temporarily during the temperature control. The operation of the convection fan is stopped at a point substantially before the point at which is automatically restarted in response to a decrease in the detected room temperature. And, in the state where the operation of the convection fan is stopped, since the room air does not convect, the room temperature distribution becomes non-uniform, and the detection of the room temperature by the room temperature sensor is likely to be inaccurate. If the restart time of the heating operation according to the detected room temperature is too early or too late, it is likely that it is difficult to perform accurate temperature control.

[0008] Contrary to the above, if the post-purge accompanying the stop of the burner is performed for a long time in order to solve such inconvenience, the burner combustion is stopped by operating the operation switch, for example, when the user tries to go out. If you try to confirm the complete stoppage of the hot air heater when it is caused, it will take time until the hot air heater finally stops completely (stops the convection fan), and the usability is poor. turn into.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a warm air heater capable of solving such inconveniences and performing accurate post-purging in accordance with the stoppage of the operation of a heat source such as a burner. And

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a heat source unit provided in a main body case, a convection fan for heating room air by the heat source unit and causing convection, and detecting a room temperature. A room temperature detecting means, an operation switch for instructing the start / stop of the heating operation, and a temperature control according to the detected room temperature in order to perform a temperature adjustment control for making the room temperature detected by the room temperature detecting means substantially coincide with the target room temperature during the heating operation. A heat source unit control means for intermittently performing the operation / stop of the heat source unit, and when the stop of the heating operation is instructed by the operation switch during the operation of the heat source unit, to stop the operation of the heat source unit; and The convection fan is operated during the operation of the heat source section, and when the heat source section is stopped by the heat source section control means, the convection fan is continuously operated even after the heat source section is stopped. A convection fan control unit that stops the convection fan after performing the top purge.The convection fan control unit is configured to control the convection fan when the heat source unit is stopped in the temperature control control. The post-purging is a first post-purging, and the post-purging by the convection fan when the heat source section is stopped by the instruction of the operation switch is a second post-purging. The time of the first post-purging is the second post-purging. A post-purge control means for controlling the convection fan so as to be longer than the time is provided.

Further, the post-purge control means controls the rotation speed of the convection fan in the first post-purge to be lower than the rotation speed of the convection fan in the second post-purge.

The post-purge control means includes a timer for measuring an elapsed time from the start of the first and second post-purges. The post-purge control means controls the elapsed time measured by the timer. The first post-purge and the second post-purge are respectively performed by the convection fan until a predetermined time predetermined in each of the two post-purges has elapsed.
The post-purge is set to be longer than a predetermined time.

Alternatively, there is provided a temperature detecting means for detecting a temperature in the main body case near the heat source portion at the time of the first and second post-purges, and the post-purge control means detects the temperature by the temperature detecting means. The first post-purge and the second post-purge by the convection fan are performed until the temperature to be reduced falls below a predetermined temperature.

[0014]

According to the present invention, in the first post-purge when the operation of the heat source section is stopped by the heat source section control section in the temperature control, the convection fan control section is controlled by the post purge control section. The convection fan is operated for a relatively long time. This allows the room air to convect for a relatively long time even after the operation of the heat source unit is stopped, so that the room temperature becomes uniform, and the room temperature detected by the room temperature detection means reliably indicates the actual room temperature. Thus, the restart of the operation of the heat source unit according to the detected room temperature can be performed at an appropriate timing. Then, in the second post-purge when the operation of the heat source unit is stopped by the heat source unit control unit according to the instruction of the operation switch, the convection fan control unit controls the operation of the convection fan by the post purge control unit. Since the operation is completed in a relatively short time, the final operation stop of the warm air heater can be performed early.

Further, when the rotation speed of the convection fan in the first post-purge is set to be lower and the rotation speed of the convection fan in the second post-purge is set to be higher, the temperature of the heat source section is controlled in the temperature control. Since the temperature of the main body case and the like by the first post-purge when the operation is stopped is performed relatively slowly, even if the time of the first post-purge is lengthened as described above, the convection fan A situation in which the user gives a feeling of cool air by the air blowing can be avoided. At the same time, when the operation of the heat source unit is stopped by the instruction of the operation switch, the temperature of the main body case and the like by the second post-purge is rapidly reduced by a large air volume at a relatively high rotation speed of the convection fan. Therefore, it is possible to shorten the time of the second post-purge.

The control of the time between the first post-purge and the second post-purge by the post-purge control means is as follows.
For example, when the timing means is provided, the first post-purge and the second post-purge are performed until the elapsed time measured by the timing means elapses a predetermined time separately set in the first and second post-purges, At this time, by setting the predetermined time of the first post-purge to be longer and the predetermined time of the second post-purge to be shorter, the control of the time of the first and second post-purging is performed as described above. Will be

Alternatively, when the rotation speed of the convection fan in the first post-purge is set lower than the rotation speed of the convection fan in the second post-purge, when the temperature detecting means is provided, the By performing the first post-purge and the second post-purge until the temperature detected by the detecting means drops below the same predetermined temperature determined by the first and second post-purging, until the temperature drops below the predetermined temperature. Is longer for the first post-purge with a lower convection fan speed and shorter for the second post-purge with a higher convection fan speed,
As described above, the control of the first and second post-purge times is performed.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One example of the present invention will be described with reference to FIGS. FIG. 1 is a system configuration diagram of the hot air heater of the present embodiment,
FIG. 2 is a block diagram of a main part of the hot air heater of FIG. 1, and FIG.
4 is a flowchart for explaining the operation of the warm air heater of FIG.

Referring to FIG. 1, the hot air heater of the present embodiment is, for example, an FF gas hot air heater, and a burner 2 as a heat source is provided in a main body case 1 disposed in the room. The housed combustion chamber 3 and a heat exchange unit 3a connected to the combustion chamber 3
And a convection fan 4 for convection of the room air via the heat exchange unit 3a. In FIG. 1, the main body case 1 and the like are shown in a plan view.

An air supply cylinder 5 is connected to the combustion chamber 3 and extends outside the main body case 1.
The exhaust pipe 6 extending outside is connected via a heat exchange section 3a. Note that the air supply cylinder 5 and the exhaust cylinder 6 may have a coaxial double structure. The burner 2 in the combustion chamber 3 is provided in the supply cylinder 5.
Is provided with a combustion fan 7 for supplying combustion air, and a combustion fan motor 8 for rotating the combustion fan 7 is connected to the combustion fan 7. The open ends of the supply cylinder 5 and the exhaust cylinder 6 are led out.

The burner 2 in the combustion chamber 3 is constituted by a plurality of mixing sections 12 which are respectively opposed to a plurality of nozzles 11 provided in a gas supply pipe 9 which is piped and introduced from outside the main body case 1. I have. Each mixing unit 12 sucks and mixes the fuel gas ejected from each nozzle 11 and the combustion air introduced into the combustion chamber 3 from the air supply cylinder 5, ejects the mixture from the tip, and burns the mixture. . And the combustion chamber 3
Inside, a sparker 13 for igniting the burner 2 and a frame rod 14 for detecting the presence or absence of misfire or misfire of the burner 2 are provided facing the front end side of the mixing section 12.

The gas supply pipe 9 has two on-off solenoid valves 1
5, 16 and a gas proportional valve 17 are interposed.

The convection fan 4 is provided in the main body case 1 so as to face a suction port 18 formed on the back surface of the main body case 1, and is connected to a convection fan motor 19 for rotating the convection fan. The convection fan 4 sucks the room air through the suction port 18 by the rotation thereof, and sends out the sucked air to the air passage 20 in the main body case 1 in which the heat exchange part 3a is formed. Further, the air passage 2
The air heated by the heat of combustion of the burner 2 in the heat exchanger 3a is blown into the room from an outlet 21 formed in the front part of the main body case 1, thereby convection the room air. A filter 22 is attached to the suction port 18, and a louver 23 for adjusting the blowing direction of hot air is provided to the outlet 21.
Has been assembled.

A room temperature sensor 24 (room temperature detecting means) for detecting the temperature (room temperature) of the room air sucked by the convection fan 4 is provided at a rear portion in the main body case 1 so as to face the suction port 18.

Referring to FIG. 1 and FIG. 2, the gas hot air heater of the present embodiment further includes a controller 25 for controlling the heating operation, and a user instructing the start / stop of the heating operation. And an operation device 28 having a room temperature setting switch 27 and the like.

As shown in FIG. 2, the controller 25
A microcomputer 29 (hereinafter referred to as a microcomputer 29) and drive circuits 30 to 34 for driving the sparker 13, the open / close solenoid valves 15, 16, the gas proportional valve 17, the combustion fan motor 8, and the convection fan motor 19, respectively. Have.

The microcomputer 29 has a combustion control section for controlling the combustion of the burner 2 via a sparker driving circuit 30, an electromagnetic valve driving circuit 31, a proportional valve driving circuit 32 and a combustion fan driving circuit 33 as its main functional components. 35 (heat source control means) and a convection fan control section 36 (convection fan control means) for controlling the operation of the convection fan motor 19 via a convection fan drive circuit 34. Further, the convection fan control unit 36 has a post purge control unit 37 (post purge control means) for controlling the post purge by the convection fan 4 when the burner 2 stops burning. The system includes a rotation speed setting unit 38 for setting the rotation speed of the convection fan 4, a time setting unit 39 for setting the post-purge time, and a timer 40 (time measuring means) for measuring the elapsed time of the post-purge.

The microcomputer 29 receives signals from the frame rod 14, the room temperature sensor 24, the operation switch 26 of the operation device 28, the room temperature setting switch 27, etc., to indicate whether or not the burner 2 has misfired, and to indicate the detected room temperature. ,
In addition, a signal indicating the stop / instruction of the heating operation by the user, a signal indicating the target room temperature, and the like are provided, and based on those signals, the operation of the warm air heater through the respective drive circuits 30 to 34 as described later. Perform control.

Next, the operation of the gas warm air heater of this embodiment will be described.

Referring to FIG. 3, when the operation switch 26 of the operation device 28 is turned ON (STEP 1), the operation device 28 is turned on.
From the controller 25 to the microcomputer 29 of the controller 25. The microcomputer 29 receiving this signal
First, the combustion control unit 35 drives the combustion fan motor 8 via the combustion fan drive circuit 33 to start the rotation operation of the combustion fan 7 (STEP 2). To perform pre-purge of the combustion chamber 3 (STEP 3). This pre-purge is performed by rotating the combustion fan 7 at a predetermined number of revolutions determined for pre-purge for a predetermined time.

After performing the pre-purge of the combustion chamber 3, the combustion control unit 35 of the microcomputer 29 drives the sparker 13 via the sparker driving circuit 30 (STEP 4), and further, the solenoid valves 15 and 16 of the gas supply pipe 9. Is opened via the electromagnetic valve drive circuit 31 and the proportional valve drive circuit 32 supplies electricity to the gas proportional valve 17 to supply a predetermined amount of fuel gas to the burner 2 for ignition of the burner 2 ( (STEP 5). Thus, the ignition process of the burner 2 is performed. During the ignition process, the combustion fan 7
The combustion engine 3 is rotated at a predetermined rotation speed so that an amount of air corresponding to a predetermined amount of fuel gas supplied to the burner 2 is supplied to the combustion chamber 3.

At the time of this ignition processing, the microcomputer 29
According to the signal obtained from the frame rod 14, the burner 2
Is monitored (STEP 6), and if the ignition is detected and the combustion of the burner 2 is confirmed (YES in STEP 6), the convection fan control unit 36
Convection fan motor 19 via convection fan drive circuit 34
To start the rotation operation of the convection fan 4 (STE
P7) Also, the operation of the sparker 13 is stopped by the combustion control unit 35 via the sparker driving circuit 30 (STE).
P8). Thereby, the convection of the room air by the convection fan 4 is started, and the room air sucked by the convection fan 4 from the suction port 18 of the main body case 1 at the time of the convection flows through the blowing passage 20 in the main body case 1 to the outlet 21. In the process of flowing toward the burner 2, it is heated via the heat exchange section 3a heated by the combustion heat of the burner 2, and is blown out from the outlet 21 as warm air.

When the combustion of the burner 2 and the operation of the convection fan 4 are started, the microcomputer 29 performs a temperature control (STEP 9).

In this temperature control, the microcomputer 29
The combustion control unit 35 controls the combustion amount of the burner 2 so that the target room temperature set by the user with the room temperature setting switch 27 of the operating device 28 matches the room temperature detected by the room temperature sensor 24. The rotation speed of the convection fan 4 is controlled (500 to 1000 rpm) via the convection fan drive circuit 34 and the convection fan motor 19 by the convection fan control unit 36 in accordance with the combustion amount and the like, and Controls the amount of hot air blown. Combustion control unit 3
5 controls the amount of gas supplied to the burner 2 according to the amount of electricity supplied to the gas proportional valve 17 and the amount of air supplied to the combustion chamber 3 according to the rotation speed of the combustion fan 7, respectively. Proportional valve drive circuit 3 according to the deviation between the detected room temperature and the target room temperature
2 and control via the combustion fan drive circuit 33. In this case, basically, the room temperature sensor 24
As the detected room temperature approaches the target room temperature, the combustion amount of the burner 2 is reduced, and the rotation speed of the convection fan 4 is reduced to reduce the amount of hot air blown.

In this temperature control, even if the combustion amount of the burner 2 is controlled as described above, the room temperature sensor 2
When the detected room temperature in Step 4 becomes higher than the target room temperature, for example, when the detected room temperature becomes higher than the target room temperature + 0.33 ° C. (YES in STEP 10), the microcomputer 29 temporarily stops the combustion of the burner 2 (STEP 11). When the combustion of the burner 2 is stopped, the combustion control unit 35 of the microcomputer 29 closes the open / close solenoid valves 15 and 16 via the solenoid valve drive circuit 31 and the gas proportional valve 1 by the proportional valve drive circuit 32.
7, the supply of gas to the burner 2 is cut off,
In addition, the combustion fan 7 is stopped via the combustion fan drive circuit 33, whereby the combustion of the burner 2 is stopped.

On the other hand, the convection fan controller 3 of the microcomputer 29
6, when the combustion of the burner 2 is stopped in this way, the post-purge control unit 37 keeps the operation of the convection fan 4 continued even after the combustion of the burner 2 is stopped.
A post-purge (first post-purge) is performed to release residual heat in the inside (STEPs 12 to 14). In the first post-purge, the post-purge control unit 37 controls the rotation number setting unit 38 to set the rotation speed of the convection fan 4 to a relatively low predetermined rotation speed (lower than the second post-purging described later) (for example, 5 rotations).
00 rpm) and a relatively long post-purge time (for example, 180 seconds) is set by the time setting unit 39 (e.g., longer than a second post-purge described later), and the convection fan 4 is set at the set rotation speed (500 rpm). Then, the convection fan motor 19 is controlled via the convection fan drive circuit 34 so as to rotate, and the timer 40 is started simultaneously with the start of the control (STEP 12).

The post-purge control unit 37 determines that the time measured by the timer 40 is equal to the post-purge time (180
Second) (YES in STEP 13), the convection fan 4 is stopped via the convection fan drive circuit 34 and the convection fan motor 19 (STEP 14). By performing such post-purging, the residual heat in the main body case 1 is discharged while the convection of the indoor air is continued, and the main body case 1
Overheating is prevented.

Next, after stopping the combustion of the burner 2, the microcomputer 29 determines that the room temperature detected by the room temperature sensor 24 drops below the target room temperature (YES in STEP 15),
The processing from EP1 is performed again. As a result, the burner 2 is ignited again and its combustion is resumed as described above, and further, temperature control is performed, and control of the combustion amount of the burner 2 and stop of the combustion are appropriately performed according to the detected room temperature. Will be If the detected room temperature drops below the target room temperature during the first post-purging, the microcomputer 29 (ST
YES in EP16), the post-purge control unit 3
7 is interrupted, and the processing from STEP 1 is restarted as in the above case.

In such a heating operation, especially when combustion of the burner 2 is restarted after the end of the first post-purge by the convection fan 4, convection of the room air by the convection fan 4 is not performed. Room temperature sensor 24 in state
Although the combustion of the burner 2 is restarted in accordance with the detected room temperature, the time (180 seconds) during which the first post-purge is performed is a relatively long time, so that the room temperature distribution in the room is sufficiently uniform. I have. Therefore, the detected room temperature obtained by the room temperature sensor 24 after the end of the first post-purge correctly indicates the actual room temperature. Therefore, it is necessary to surely restart the combustion of the burner 2 or the like at an appropriate time. Can be. Further, the convection fan 4 in the first post-purge is used.
Since the rotation speed (500 rpm) is relatively low, the removal of the residual heat in the main body case 1 is performed gently. Therefore, even if the first post-purging time is relatively long, It is possible to avoid a situation in which a low-temperature air that gives the user a feeling of cool air is blown during the one-post purging.

During the first post-purge, the burner 2
When the combustion or the like is restarted, the convection of the indoor air by the convection fan 4 is performed, so that the actual room temperature can be correctly detected by the room temperature sensor 24, and therefore, it is ensured. Burning of the burner 2 can be restarted at an appropriate time.

On the other hand, referring to FIG. 4, when the operation switch 26 is turned off (STEP 17) while the burner 2 is burning in the heating operation as described above,
The microcomputer 29 stops the combustion of the burner 2 similarly to the case of STEP 11 in FIG. 3 (STEP 18), and further performs a post-purge (second post) to the convection fan 4 by the post-purge control unit 37 of the convection fan control unit 36. purge)
(STEPs 19 to 21). In the second post-purge, the post-purge control unit 37 controls the rotation number setting unit 38 to set the convection fan 4 to a relatively high (e.g., higher than the first post-purge) predetermined rotation speed (for example, 80).
0 rpm) and a relatively short post-purge time (for example, 120 seconds) is set by the time setting unit 39 (shorter than the above-mentioned first post-purge), and the convection fan 4 is set at the set rotation speed (800 rpm). The convection fan motor 19 is controlled via the convection fan drive circuit 34 so as to rotate, and the timer 4 is started simultaneously with the start of the control.
0 is started (STEP 19).

The post-purge control unit 37 determines that the time measured by the timer 40 is equal to the post-purge time (120
Second) (YES in STEP 20), the convection fan 4 is stopped via the convection fan drive circuit 34 and the convection fan motor 19 (STEP 21). Thereby, the operation of the warm air heater is completely stopped.

In such a second post-purge,
Since the time (120 seconds) is relatively short, the user can turn off the operation switch 26 and confirm the complete stoppage of the operation of the hot air heater in a short time, which is convenient. Although the post-purge time (120 seconds) is relatively short, the rotation speed (80
0 rpm) is relatively high, so that the residual heat in the main body case 1 can be sufficiently dissipated within the post-purge time.

In this embodiment, the post-purging time and the rotation speed of the convection fan 4 are kept constant in the first post-purge and the second post-purge, respectively. However, immediately before the combustion of the burner 2 is stopped. Burner 2 burner and body case 1
The post-purging time and the rotation speed of the convection fan 4 may be variably set for the first post-purge and the second post-purge, respectively, according to the internal temperature of the refrigerator. However, in this case, the first post-purge time is set to the first post-purge time and the second post-purge as long as the burner 2 combustion amount immediately before the burner 2 is stopped is the same. The post-purging time is set to be longer than the two-post purging time, and if necessary, the rotation speed of the convection fan 4 in the first post-purging is lower than the rotation speed of the convection fan 4 in the second post-purging. For this purpose, the rotation speed of the convection fan 4 is set. Further, during the post-purge, the rotation speed of the convection fan 4 may be gradually decreased with time.

Next, another example of the hot air heater of the present invention is shown in FIG.
This will be described with reference to FIG. FIG. 5 is a block diagram of a main part of the hot air heater of the present embodiment, and FIG. 6 is a flowchart for explaining the operation of the hot air heater of the present embodiment.
The basic configuration of the hot air heater of the present embodiment is the same as that of the gas hot air heater of FIG. 1, and the same components are denoted by the same reference numerals and will be described in detail. Omitted.

Referring to FIG. 5, the gas hot air heater of the present embodiment is, for example, a heat exchanger 3a in the main body case 1 of FIG.
And a temperature sensor 41 (temperature detecting means) for detecting the temperature of the controller 25. The temperature detected by the temperature sensor 41 is supplied to the microcomputer 29 of the controller 25. Then, the post-purge control unit 37 of the convection fan control unit 36 of the microcomputer 29
Is configured to control post-purge according to the temperature detected by the temperature sensor 41 as described later. in this case,
The post-purge control unit 37 includes a rotation speed setting unit 38 as in the embodiment of FIG. 1, but does not include a time setting unit and a timer. Other configurations are exactly the same as those of the embodiment of FIG.

Next, the operation of the gas hot air heater of the present embodiment will be described. The operation of the gas hot air heater of this embodiment is different from that of the embodiment of FIG. 1 only in the operation of the post-purge. Therefore, only the operation of the post-purge will be described, and other operations will be described. Description is omitted.

Referring to FIG. 6A, when the combustion of the burner 2 is stopped by the above-described temperature control, the microcomputer 29 controls the post-purge control unit 3 of the convection fan control unit 36.
7, the first post-purge is performed as follows.

That is, the post-purge control unit 37 sets a relatively low predetermined rotation speed (500 rpm) of the convection fan 4 by the rotation speed setting unit 38 and rotates the convection fan 4 at the set rotation speed (500 rpm). The convection fan motor 19 is controlled via the convection fan drive circuit 34 so as to perform the first post-purge.
(STEP 22).

When the temperature detected by the temperature sensor 41 drops below a predetermined temperature (for example, 35 ° C.) (YES in STEP 23), the post-purge control unit 37 sends the convection fan drive circuit 34 and the convection fan motor 19 via the convection fan motor 19. The convection fan 4 is stopped (STEP 24). The predetermined temperature is determined, for example, as a temperature in a state where the residual heat in the main body case 1 is appropriately discharged. Then, after the completion of the first post-purge, or the microcomputer 29,
During the first post-purge, the room temperature detected by the room temperature sensor 24 drops below the target room temperature (STEP 25 or 26).
And YES), the combustion of the burner 2 and the like are restarted as in the above-described embodiment.

In such a first post-purge,
Since the rotation speed (500 rpm) of the convection fan 4 is set to a lower rotation speed, the temperature detected by the temperature sensor 41 gradually decreases, and as a result, the time required for the temperature to drop below the predetermined temperature is consequently increased. Is relatively long. Therefore, similarly to the case of the above-described embodiment, especially when the combustion of the burner 2 is restarted after the end of the first post-purge, the room temperature distribution at the time of the restart becomes uniform, and
The detected room temperature obtained by the room temperature sensor 24 correctly indicates the actual room temperature, whereby the combustion of the burner 2 can be surely restarted at an appropriate time. In addition, since the rotation speed (500 rpm) of the convection fan 4 in the first post-purge is relatively low, a low-temperature wind that gives a feeling of cool air to the user during the first post-purge is blown. This avoids the situation.

On the other hand, referring to FIG. 6B, the burner 2 is turned off by operating the operation switch 26 while the burner 2 is burning.
Is stopped, the post-purge control unit 37 of the microcomputer 29 performs the second post-purge as follows.

That is, the post-purge control unit 37 sets a relatively high predetermined rotation speed (800 rpm) of the convection fan 4 by the rotation speed setting unit 38 and rotates the convection fan 4 at the set rotation speed (800 rpm). Then, the second post-purge is performed. (STEP 27).

When the temperature detected by the temperature sensor 41 drops below the predetermined temperature (35 ° C.) (YES in STEP 28), the post-purge controller 37 stops the convection fan 4 (STEP 29), The operation of the machine stops completely.

In such a second post-purge,
Since the rotation speed (800 rpm) of the convection fan 4 is set to a higher rotation speed, the temperature detected by the temperature sensor 41 rapidly decreases, and as a result, the time until the temperature decreases to the predetermined temperature or less is consequently obtained. Is relatively short. Therefore,
As in the case of the above-described embodiment, the usability of the warm air heater can be improved.

In the first and second post-purges of the gas hot air heater of this embodiment, as long as the temperature detected by the temperature sensor 41 when the burner 2 stops combustion is the same.
Although the former post-purging time is longer than the latter, the higher the temperature detected by the temperature sensor 41, the longer the post-purging time of both. For this reason, the remaining heat can be accurately dissipated with a post-purge time suitable for the temperature due to the remaining heat in the main body case 1.

In the present embodiment, the rotation speed of the convection fan 4 is kept constant between the first post-purge and the second post-purge, however, the combustion of the burner 2 immediately before the combustion of the burner 2 is stopped. The rotation speed of the convection fan 4 may be variably set for each of the first post-purge and the second post-purge according to the amount, the internal temperature of the main body case 1 and the like. However, in this case, as long as the combustion amount of the burner 2 immediately before the combustion of the burner 2 is stopped in the case of the first post-purge and the case of the second post-purge, the convection fan 4 in the first post-purge is used. Is set lower than the rotation speed of the convection fan 4 in the second post-purge, and the rotation speed of the convection fan 4 is set. During the post-purge, the rotation speed of the convection fan 4 may be gradually reduced in accordance with the degree of decrease in the temperature detected by the temperature sensor 41.

In each of the embodiments described above,
Although an FF type hot air heater has been described as an example, the present invention can of course be applied to, for example, a fan heater, and a petroleum burner or an electric heater other than a gas burner is used as a heat source. The present invention can be applied to such a hot air heater.

[0059]

As is apparent from the above description, according to the present invention, when the operation of the heat source unit is stopped by the temperature control, the post-purging is performed by the first post-purge, and the operation of the heat source unit is instructed by the operation switch. The post-purge when the operation is stopped is distinguished as the second post-purge, and the time of the first post-purge is set to be longer than the time of the second post-purge. When the operation of the heat source unit can be resumed at an appropriate timing according to the detected room temperature by the room temperature detection means, while the operation of the heat source unit is stopped by the operation switch The second post-purge can be completed in a short time, the usability can be improved, and an accurate post-purge according to the stopped state of the operation of the heat source section can be performed. It can be.

Further, by setting the rotation speed of the convection fan in the first post-purge lower than the rotation speed of the convection fan in the second post-purge, the temperature control can be performed even if the time of the first post-purge is relatively long. Thus, it is possible to avoid a situation in which the first post-purge gives the user a feeling of cool air before the operation of the heat source unit is restarted, and at the same time, the operation of the heat source unit is stopped by the operation switch. In this case, the second post-purge allows the residual heat in the main body case to be quickly and quickly dissipated in a short time,
The second post-purge can be completed in a shorter time.

The first and second post-purges may be performed for a predetermined period of time, respectively. However, the rotation speed of the convection fan of the first post-purge may be reduced by the rotation speed of the convection fan of the second post-purge. If the temperature is lower than the predetermined temperature, the temperature is detected by temperature detecting means provided in the vicinity of the heat source unit, and the first temperature is detected until the detected temperature falls below a predetermined temperature.
By performing the second post-purging, the time of the first post-purging can be made longer than the time of the second post-purging with a simple configuration, and the temperature due to the residual heat in the main body case 1 can be reduced. With a suitable post-purging time, the remaining heat can be properly dissipated.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a gas warm air heater according to an example of the present invention.

FIG. 2 is a block diagram of a main part of the hot air heater of FIG. 1;

FIG. 3 is a flowchart for explaining the operation of the warm air heater of FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the warm air heater of FIG. 1;

FIG. 5 is a block diagram of a main part of a gas hot air heater according to another example of the present invention.

FIG. 6 is a flowchart for explaining the operation of the warm air heater of FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Body case, 2 ... Burner (heat source part), 4 ... Convection fan, 24 ... Room temperature sensor, 26 ... Operation switch, 35 ... Combustion control part (Heat source part control means), 36 ... Convection fan control part, 37 ... Post Purge control unit, 40 ... time measuring means, 41
... Temperature sensor.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F24H 3/04 305 F23N 5/24 106 F24H 3/06 304

Claims (4)

(57) [Claims] 1. A heat source provided in a main body case, a convection fan for convection while heating room air by the heat source, a room temperature detecting means for detecting a room temperature, and an operation of a heating operation.
An operation switch for instructing a stop, and intermittently operating / stopping the heat source unit in accordance with the detected room temperature in order to perform a temperature control that substantially matches a room temperature detected by the room temperature detection unit with a target room temperature during a heating operation. When the heating switch is instructed by the operation switch to stop the heating operation during the operation of the heat source unit, the heat source unit control means for stopping the operation of the heat source unit, and the convection fan during the operation of the heat source unit. Convection fan control for operating the convection fan when the heat source unit is stopped by the heat source unit control means, continuing the operation of the convection fan even after the heat source unit is stopped, performing post-purging, and then stopping the convection fan Means, the convection fan control means performs post-purging by the convection fan when the heat source section is stopped in the temperature control control. One post purge, a post purge by the convection fan when the heat source unit is stopped by an instruction of the operation switch is a second post purge, and the time of the first post purge is longer than the time of the second post purge. A hot air heater comprising a post-purge control means for controlling the convection fan. 2. The post-purge control means controls the rotation speed of the convection fan in the first post-purge to be lower than the rotation speed of the convection fan in the second post-purge. Hot air heater. 3. A post-purge control means for measuring an elapsed time from the start of said first and second post-purges, wherein said post-purge control means measures the elapsed time measured by said time-measuring means. The first post-purge and the second post-purge are respectively performed by the convection fan until a predetermined time predetermined in each of the two post-purges has elapsed. The predetermined time of the first post-purge is the predetermined time of the second post-purge. The hot air heater according to claim 1 or 2, wherein the length is set to be longer. 4. A temperature detecting means for detecting a temperature in the main body case near the heat source part at the time of the first and second post-purges, wherein the post-purge control means detects the temperature by the temperature detecting means. The first convection fan operates until the temperature of the convection fan drops below a predetermined temperature.
3. The hot air heater according to claim 2, wherein the post-purge and the second post-purge are performed.