JPH06159674A - Warm-air heater - Google Patents

Abstract

PURPOSE:To improve user's convenience while obtaining reliability by effectively setting post-purging time after combustion is finished. CONSTITUTION:A controller 19 has a thermocouple 24 for detecting s burning state of a burner, and post-purge control means 33 for setting a post-purging time after combustion is finished in response to a detected output of the thermocouple 24 and burning time before an operation is started. Thus, when the detected output of the thermocouple 24 before the operation is started is small, even if a burning time is short, the post-purging time is increased, and when the detected output of the thermocouple 24 before the start of the operation is small, the post-purging time is regulated in response to the burning time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a warm air heater, such as a gas fan heater or an oil fan heater, which discharges indoor air heated by combustion gas of a burner as warm air into a room.

[0002]

2. Description of the Related Art Conventionally, for example, in a gas fan heater, as disclosed in Japanese Utility Model Publication No. 63-50602, a burner and this burner are faced in an outer case having an air inlet and a warm air outlet. It is known that a combustion chamber and a blower fan that supplies the air sucked from the air suction port to the burner and discharges the combustion gas from the hot air outlet are provided with a control device that controls combustion in the burner and the blower fan. Has been.

Further, this type of hot-air heater controller is provided with a post-purge control means for operating the blower fan after the end of combustion, and the temperature inside the outer case becomes abnormal due to the residual heat of the combustion chamber after the end of combustion. It does not rise and internal parts are not damaged or deteriorated.

[0004]

By the way, the post-purge time by the post-purge control means is set to a fixed value or is set according to the combustion time. When the post-purge time is set constant, the post-purge time is set to a long time, so that the post-purge operation may be performed more than necessary, and there is a concern that the user may feel uncomfortable. Also, when set according to the combustion time, when the heating operation is repeatedly performed, the residual heat may be large even if the combustion time is short, and if the post-purge time is shortened according to the combustion time,
There was a concern that the temperature inside the outer case would rise after the completion of post-purging, and internal parts would be damaged or deteriorated.

The present invention has been made in view of the above-mentioned facts, and it is an object of the present invention to accurately set the post-purge time after the end of combustion and improve the usability for the user while ensuring reliability.

[0006]

According to the present invention, a burner is provided in an exterior case having an air inlet and a hot air outlet, a combustion chamber facing the burner, and air is introduced into the exterior case from the air inlet. In addition to the above, a hot air heater provided with a blower fan for discharging the air heated by the combustion gas of the burner, and a hot air heater provided with a control device for controlling the combustion and blower fan in the burner, the control device being a burner And a post-purge control means for setting the post-purge time after the end of combustion according to the detection output of the thermocouple before the start of operation and the combustion time.

Further, according to the present invention, the burner is provided in the outer case having the air suction port and the hot air outlet, the combustion chamber facing the burner, and the air is introduced from the air suction port into the outer case. In a warm air heater provided with a blower fan for discharging the air heated by the combustion gas of the burner and having a control device for controlling the combustion in the burner and the blower fan, the control device controls the internal temperature of the outer case. The temperature detector for detection and the post-purge control means for setting the post-purge time according to the temperature detected by the temperature detector and the combustion time are provided.

[0008]

With this configuration, when the thermocouple before the start of operation is small, the post-purge time is lengthened even if the combustion time is short, and when the detection output of the thermocouple before the start of operation is small, the combustion time is adjusted accordingly. The post-purge time can be adjusted, and it is possible to prevent the user from feeling uncomfortable as much as possible and prevent the internal temperature in the outer case from rising abnormally.

Further, according to the second aspect, when the temperature detected by the temperature detector at the end of combustion is high, the post-purge time is lengthened even if the combustion time is short, and the temperature detector at the end of combustion detects the temperature. When the temperature is low, the post-purge time can be adjusted according to the combustion time, and it is possible to prevent the user from feeling uncomfortable as much as possible and prevent the internal temperature in the outer case from rising abnormally.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment in which the present invention is applied to a gas fan heater will be described below with reference to the drawings.

In FIG. 7, reference numeral 1 denotes an outer case having an air inlet 2 having an air filter F attached to the upper rear surface thereof, and a warm air outlet 3 provided to the lower front portion thereof, and 4 is provided in an upper portion of the outer case 1. The combustion chamber 5 is a gas burner provided in the combustion chamber 4, a blower fan 6 is a cross-flow fan provided under the combustion chamber 4, a cover plate 7 covers the upper surface and the front surface of the combustion chamber 4, Is a ventilation passage which is interposed between the combustion chamber 4 and the cover plate 7 and which guides the air flowing in from the suction port 2 and the combustion gas from the combustion chamber 4 to the ventilation fan 6, and 9 warms the warm air from the ventilation fan 6. Fan casing 10 that guides to the air outlet 3
Is an automatic winding type cord reel device provided in a lower space 12 in the outer case 1 partitioned by the fan casing 9.

The cord reel device 10 has a protective cover 13 made of resin so that the power cord 14 can be taken in and out from the lower portion of the rear surface of the outer case 1. Further, the power cord 14 is pulled out manually, and when the power cord 14 is stored, the power cord 14 is pulled and released by hand so that the power cord 14 is automatically wound.

Numerals 15 and 16 designate a rectifying plate which also functions as a heat shield plate provided in an air passage 17 between the cover plate 7 and the outer case 1.
8 is a stand that also serves as the bottom plate of the outer case 1, 19 is a control device, 20 is operation circuit parts such as an operation switch 21, 22 is a room temperature detector made of a thermistor, 23 is a clogging detector made of a thermistor, and 24 is a gas burner. A room temperature detector 22 is arranged near the air inlet 2, a clogging detector 23 is arranged on the cover plate 7, and a thermocouple 24 is arranged near the gas burner 5. There is.

FIG. 1 shows the basic configuration of the control device 19. In FIG. 1, reference numeral 25 is a microcomputer (hereinafter, referred to as a microcomputer) having a built-in A / D converter. Clog detector 2
3 and a thermocouple 24 are provided. Further, on the output side of the microcomputer 25, a source solenoid valve 27 and a proportional control valve 28 inserted in a gas supply pipe (not shown) of the gas burner 5,
An igniter 29, a motor FM for driving the blower fan 6, a filter lamp 30 as a clogging indicator, and an alarm lamp 31 are provided. Further, the microcomputer 25 has a flame discrimination means 32 and a post-purge control means 33 built therein.

The drive motor FM is provided with a rotation speed detector 34, and its detection signal is input to the microcomputer 25. Further, the temperature setting device 26 and the filter lamp 30 are arranged together with the operation switch 21 on the upper front surface of the outer case 1.

When the operation switch 21 is turned on, the microcomputer 25 opens the original solenoid valve 27 and the proportional control valve 28,
The igniter 29 is operated and the drive motor FM of the blower fan 6 is started. At this time, the indoor air is sucked into the exterior case 1 from the air suction port 2 by the blower fan 6, and a part thereof enters the combustion chamber 4 through the intake port 4A. And this air is the original solenoid valve 27 and the proportional control valve 2
It is mixed with the gas fuel supplied via 8 and burned in the gas burner 5.

After the combustion gas of the gas burner 5 is discharged from the exhaust port 4B, the air in the air passage 8 for cooling the outer wall of the combustion chamber 4 and the control device 1 for the upper and front parts of the outer case 1 are formed.
9 and the air that suppresses the temperature rise of the operation circuit component 20 and the air, and are sucked into the blower fan 6. Then, the warm air discharged from the blower fan 6 is guided to the warm air outlet 3 along the fan casing 9 and discharged into the room.

During such a heating operation, the microcomputer 25 determines the fuel consumption amount in the gas burner 5 in accordance with the magnitude of the temperature difference between the temperature set by the temperature setter 26 and the temperature detected by the room temperature detector 22. For example, as shown in FIG. 2, the fuel consumption is 6
In the range of 00 kcal / h to 3000 kcal / h, multi-step or stepless adjustment is performed. Then, the microcomputer 25 uses the proportional control valve 28 to obtain this fuel consumption amount.
The valve opening of the control unit to control the amount of fuel supplied to the gas burner 5 and control the rotation speed of the drive motor FM.
The amount of air supplied to the gas burner 5 by the blower fan 6 is controlled.

The rotation speed of the drive motor FM is controlled by the rotation speed signal from the rotation speed detector 34 and the set rotation speed (here, FIG. 2).
(Set in the range of 550 rpm to 1230 rpm), the voltage control or the phase control of the drive motor FM is performed so that the rotation speed of the blower fan 6 becomes the set rotation speed.

In this way, the fuel consumption in the gas burner 5 is precisely controlled according to the heating load, so that the room temperature is maintained near the set temperature. When the room temperature rises close to the set temperature, the fuel consumption amount in the gas burner 5 becomes the minimum, the rotation speed of the blower fan 6 becomes the minimum, and the operation is performed with low noise.

When the air filter F is clogged,
The temperature detected by the clogging detector 23 rises. Then, when the detected temperature exceeds a predetermined temperature, the microcomputer 2
5 turns on the filter lamp 29 to prompt the customer to clean the air filter-F. Of course, when the air filter F is used as it is without being cleaned, the temperature detected by the clogging detector 23 further rises. When the detected temperature exceeds the high limit temperature, the microcomputer 25
Stops combustion in the gas burner 5 and switches the filter lamp 29 from a lighting state to a blinking state to notify the customer that the gas fan heater has been forcibly stopped.

Flame discriminating means 3 built in the microcomputer 25
2, as shown in FIG. 3, the detection output Tc of the thermocouple 24 and the ignition set value Tb are compared to determine the presence or absence of ignition. Also, during heating operation, the output of the thermocouple 24 is compared with the fire setting value Td, and when the detected output of the thermocouple 24 approaches the fire setting value Td due to a decrease in oxygen concentration, the alarm lamp 31 is turned on, Promote ventilation in the room. As a matter of course, if the thermocouple 24 is used as it is without being ventilated, the detection output Tc of the thermocouple 24 further decreases. Then, when this detection output becomes equal to or less than the fire break setting value Td, the microcomputer 25
Stops the combustion in the gas burner 5 and switches the alarm lamp 31 from a lighting state to a blinking state to notify the customer that the gas fan heater has been forcibly stopped.

As shown in FIG. 4, the post-purge control means 33 stores the detected output Tc of the thermocouple 24 before the heating operation is started, and the post-combustion post-combustion is determined according to the detected output Tc and the combustion time. The purge time is set and the blower fan 6 is operated.

That is, when the detection output Tc of the thermocouple 24 before the start of the heating operation is equal to or higher than the set value Ts smaller than the set ignition value, the post purge time is long (90 seconds) regardless of the combustion time. To In such a case, it is considered that the heating operation is restarted before the internal temperature of the outer case 1 has fallen sufficiently. Therefore, regardless of the combustion time, the post-purge is performed sufficiently to ensure the internal temperature. To prevent the abnormal rise of.

On the other hand, when the detection output Tc of the thermocouple 24 before the start of the heating operation is smaller than the set value Ts, the post purge time is set according to the combustion time. For example, when the combustion time is within 10 seconds, the post-purge time is 10-20.
Seconds, and when the combustion time is between 10 and 60 seconds, the post-purge time is set to 60 seconds and the combustion time is 6 seconds.
When it is 0 seconds or more, the post purge time is set to 90 seconds. For this reason, it is possible to prevent the post-purging from being performed more than necessary, to prevent the user from feeling uncomfortable, and to improve the usability.

FIG. 5 shows another example of the post-purge control means 33. In this embodiment, it is determined whether the temperature To detected by the clogging detector 23 at the end of combustion is equal to or higher than a predetermined value Tx (normal temperature plus several tens of degrees). No Longer post-purge time (90 seconds). In such a case, the outer case 1
Since it is considered that the heating operation is restarted before the internal temperature of the internal combustion engine has sufficiently decreased, the post-purge is sufficiently performed to prevent the abnormal increase of the internal temperature regardless of the combustion time.

On the other hand, when the temperature To detected by the clogging detector 23 at the end of combustion is lower than the predetermined value Tx, the post purge time is set according to the combustion time. For example, when the combustion time is within 10 seconds, the post-purge time is 10-2.
The post-purge time is set to 0 seconds, the post-purge time is set to 60 seconds when the combustion time is between 10 seconds and 60 seconds, and the post-purge time is set to 90 seconds when the combustion time is 60 seconds or more. For this reason, it is possible to prevent the post-purging from being performed more than necessary, to prevent the user from feeling uncomfortable, and to improve the usability.

Incidentally, as shown in FIG. 6, after the post-purging is performed for a time corresponding to the combustion time, the clogging detector 2
Detection temperature Tx of 3 is a predetermined value Ty (normal temperature plus alpha)
The post-purge may be continued until the temperature falls below the temperature, or the post-purge may be ended after a predetermined time after the temperature detected by the clogging detector 23 reaches a predetermined value.

[0029]

EFFECTS OF THE INVENTION Since the present invention is configured as described above, in the one described in claim 1, when the thermocouple before the start of operation is small, the post-purge time can be lengthened even if the combustion time is short, When the detection output of the thermocouple before the start of operation is small, the post-purge time can be adjusted according to the combustion time, and the internal temperature inside the outer case is abnormal while keeping the user as comfortable as possible. Therefore, it is possible to maintain the reliability of the user while maintaining reliability.

Further, according to the second aspect, when the temperature detected by the temperature detector at the end of combustion is high, the post-purge time can be lengthened even if the combustion time is short, and the temperature detector at the end of combustion detects the temperature. When the temperature is low, the post-purge time can be adjusted according to the combustion time to prevent the user from feeling uncomfortable as much as possible and to prevent the internal temperature inside the outer case from rising abnormally. The user-friendliness can be maintained while ensuring the above.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a control device for a gas fan heater to which the present invention is applied.

FIG. 2 is a control characteristic explanatory diagram of the control device.

FIG. 3 is another explanatory view of control characteristics of the control device.

FIG. 4 is a flow chart for explaining the control operation of the control device.

FIG. 5 is a flow chart for explaining another control operation of the control device.

FIG. 6 is a flow chart for explaining another control operation of the control device.

FIG. 7 is a schematic configuration explanatory diagram of a gas fan heater showing an example of a warm air heater.

[Explanation of symbols]

 1 Outer Case 2 Air Suction Port 3 Hot Air Outlet 4 Combustion Chamber 5 Gas Burner 6 Blower Fan 23 Clog Detector (Temperature Detector) 24 Thermocouple 33 Postpurge Control Means

Claims (2)

[Claims] 1. A burner in an outer case having an air inlet and a hot air outlet, and a combustion chamber facing the burner,
A ventilation fan is provided to let air flow into the outer case from the air inlet and to discharge the air heated by the combustion gas of the burner, and to control the combustion in the burner and the control device that controls the ventilation fan. In a wind heater, the control device has a thermocouple that detects the combustion state in the burner, and post-purge control that sets the post-purge time after the end of combustion according to the detection output of the thermocouple and the combustion time before the start of operation. A warm air heater characterized by having means. 2. A burner in a case having an air inlet and a hot air outlet, and a combustion chamber facing the burner,
A ventilation fan is provided to let air flow into the outer case from the air inlet and to discharge the air heated by the combustion gas of the burner, and to control the combustion in the burner and the control device that controls the ventilation fan. In the wind heater, the control device includes a temperature detector that detects the internal temperature of the outer case, and a post-purge control unit that sets the post-purge time according to the temperature detected by the temperature detector and the combustion time. And a hot air heater.