JPH06100337B2 - Hot air heater - Google Patents

Description

TECHNICAL FIELD The present invention relates to room temperature control of a hot air heater.

2. Description of the Related Art Generally, as shown in FIGS. 5 and 6, the set value of the warm air heater is set such that the combustion start set value T _ON is equal to the set value T _H for controlling the heating output, or T _L > set in the relationship of T _oN> T _{H, H}
i-Lo-OFF The average value of temperature control when burning is stable.

Problems to be Solved by the Invention FIG. 4 shows a configuration diagram of a warm air heater. 1 is a burner, 2 is a heat exchanger, 3 is a blower fan, 4 is a room temperature detecting element, 5 is an outer case of a warm air heater, 6 is an air filter, 7 and 8 are flows on the suction side of indoor air, and 9 is discharge. It is the flow of air.

In the above configuration, when the room temperature setting unit (not shown) sets a predetermined room temperature, the temperature detected by the room temperature detecting element 4 becomes
A temperature control circuit (not shown) controls the combustion amount of the burner 1 and the air amount of the blower fan 3 so that the set temperature is reached. When the outside air temperature is low, the device operates at Hi-Lo output, and in this case, the blower fan 3 continues to rotate, so the room temperature detection element 4 is
It is in the intake air flow 7 and 8 of the room air, and can detect a temperature almost equal to room temperature. However, at the end of autumn when the outside air temperature becomes high and the season of early spring, the Hi-Lo-OFF control is performed as shown in FIG.

At the time of stop, the blower fan 3 stops, and as shown in FIG.
The room temperature detection element 4 that was in the flow of room air until then,
Overshoot due to radiant heat and convective heat from the outer case 5 due to the amount of heat accumulated in the warm air heater, causing a deviation between the detected temperature T _TH of the room temperature detection element and the actual room temperature T _{ROOM that} is felt as a room temperature. Is decreased and T _TH is the combustion start set value T
_When turned on, the temperature of T _ROOM becomes even lower, and as a result, it feels chilly, making it an inconvenient hot air heater.

The present invention solves the above-mentioned conventional problems, and provides a warm air heater having a simple structure and being easy to use and comfortable.

Means for Solving the Problems In the warm air heater of the present invention, when the detection temperature T _TH of the room temperature detection element reaches the combustion stop set value T _OFF but still overshoots, the detection temperature T _{TH of the} room temperature detection element Continues to rise and then reverses in the descending direction (temperature detected by the room temperature detection element
T _TH )-(combustion stop set value T _OFF ) = T _α calculated maximum value T _A, and temperature kT _A proportional to T _A is set to combustion start set value T _ON
To be added to.

Action The warm air heater of the present invention obtains the maximum value T _A of the overshoot temperature after the detection temperature T _TH of the room temperature detection element reaches the combustion stop set value T _OFF , and burns the temperature kT _A proportional to T _A with the arrangements as to be added to the starting setpoint T _oN, Ki out to reduce the temperature differential of the combustion stop setting value T _OFF and the combustion start setting value T _oN, resulting, stop burning,
When the room temperature decreases, it becomes possible to start combustion again at a room temperature at which chills are not felt.

Embodiment An embodiment of the present invention will be described below with reference to FIGS.
In FIG. 1, the upper figure shows the heating output state, and the lower figure shows the room temperature control state with the vertical axis as a temperature scale and the position of each set temperature and the horizontal axis as a time scale.

Now, when the outside air temperature is low, such as 0 ° C or less, the appliance repeats the heating output Hi-Lo and the blower fan 3 continues to rotate, so the room temperature detection element detects the same temperature as the room temperature and controls the temperature. Is executed faithfully to the set value (not shown). Next, when the outside air temperature is as high as 5 ° C to 10 ° C, the room temperature rises even with the heating output Lo, so the detected temperature of the room temperature detecting element 4 becomes T _OFF.
When it exceeds, the instrument stops burning (OFF). After that, the blower fan 3 was stopped, and the temperature detected by the room temperature detection element 4 followed the locus shown in Fig. 1 T _TH due to the radiant heat and convective heat from the outer case 5 due to the amount of heat accumulated in the equipment, and T _TH reached the maximum value. The overshoot T _A ℃ is read into the control circuit (Fig. 2). As a constant of proportionality k, T _β = kT _a in the control circuit,
_T'ON = T _ON + T _β is calculated, and the combustion start set value T _ON is T
Only _{β is} corrected. As a result, after the combustion is stopped, the room temperature is lowered, and after the detected temperature T _TH of the room temperature detection element 4 reaches the corrected combustion start point T ′ _ON = T _ON + T _β , the appliance starts the combustion. At this time, the temperature T _ROOM felt as a sensation is about T _β ℃ lower, but the original combustion start set temperature T _ON
The temperature is almost equal to, and the temperature control is equivalent to being faithfully executed according to the original set values T _OFF , T _L , and T _H. FIG. 2 shows an example of the control circuit. To set the room temperature, the key signal from the key signal generator 11 is read as the key input of the microcomputer 10, and the microcomputer 10 outputs a 4-bit LED output control signal to D4 to D7 to drive the display circuit 12, Display the set temperature.

At the same time, inside the microcomputer 10, the set values T _OFF , T _ON , T _L and T _H shown in FIG. 1 are set and stored as calculation results.

At room temperature, the resistance value change of the room temperature detecting element T _H 4 is converted into an electric potential, and the comparator 14 sequentially compares the 6-bit ladder output which is composed of the microcomputer 10 and the D / A converter 13 and is output, It is input to the T _h terminal of the computer 10.

SV _0, SV ₁ pin of the microcomputer 10, the output to the electromagnetic valve driving circuit 15, the room temperature is controlled by the microcomputer 10 from the relationship set temperature, at Lo combustion SV ₁
Is turned off, SV ₀ and SV ₁ are both turned on during Hi combustion, and SV is turned off when combustion is stopped.
It is configured to turn off both V ₁ and SV ₁ .

FIG. 3 illustrates the above control procedure with a flowchart.

In other words, after the ignition sequence is completed, if the detected temperature T _TH of the room temperature detection element is smaller than the set value T _L (T _TH <T _L ), H _I
Combustion occurs, and the detected temperature T _TH is between the set value T _L and T _OFF (T _L
When <T _TH <T _OFF ), Lo combustion occurs.

Next, the detected temperature T _TH exceeds the set value T _OFF (T _TH
When ≧ T _OFF ), combustion stops. And T _TH continues to rise.

After the combustion is stopped, the calculated value T _A is set to 0, and then (detected temperature
T _TH )-(set temperature T _OFF ) = T _α is calculated and
Compared with _A , T _A <T _α is stored in T _A as T _A = T _α , and when T _A ≧ T _α , T _A becomes the maximum value and T ′ _ON
Calculate and store = T _ON + kT _A. After that, T _TH continues to fall, and when T _TH ≤T ' _ON , the ignition sequence is returned to again.

Effect of the Invention As described above, the combustion start set temperature T _ON is set to T ′ _ON = T _ON + kT
_By setting _A , the temperature T detected by the room temperature detection element 4 after combustion is stopped
_{Even if TH} overshoots the combustion stop set value T _OFF , it is possible to correct the combustion start set value T _ON by the overshoot temperature, and when the room temperature decreases, you do not feel chilly as a sensation. Combustion can be restarted at room temperature, and extremely comfortable temperature control can be realized throughout the heating season from autumn to winter to spring.

[Brief description of drawings]

FIG. 1 is a diagram for explaining temperature control in one embodiment of the hot air heater of the present invention, FIG. 2 is a diagram for explaining a part of a control circuit of the hot air heater, and FIG. FIG. 4 is a flow chart of the control procedure of the temperature control circuit of the hot air heater, FIG. 4 is a configuration diagram of the hot air heater, and FIGS. 5 and 6 are diagrams for explaining conventional temperature control. 3 ... Blower fan, 4 ... Room temperature detector, 10 ... Microcomputer.

Claims (1)

[Claims] 1. A set temperature is compared with room temperature to control the heating output of the equipment from combustion stop to full output, and the temperature T _TH detected by the room temperature detection element reaches the combustion stop set value T _OFF to stop combustion. However, if it still overshoots, the temperature T _TH detected by the room temperature detector continues to rise, and then, until it reverses in the descending direction,
(Detection temperature T _TH of room temperature detection element)-(Combustion stop set value T
_OFF ) = The maximum value T _A of the calculated values of T _α is found, and this maximum value T _A
A hot-air heater equipped with means for correcting a combustion start point by adding a temperature kT _A proportional to the combustion start set value T _ON .