JPS62248930A - Electric foot warmer - Google Patents

Abstract

PURPOSE:To attempt to save energy of the foot warmer and to improve the safety thereof by providing a control circuit controlling to slightly lower the temperature within the foot warmer when a heater of the foot warmer produces a predetermined output which is reduced from the rated output thereof or the foot warmer keeps a predetermined temperature for a predetermined period of time. CONSTITUTION:When power is supplied to a heater 1 of the foot warmer, the temperature of the foot warmer rises and reaches a set value in a short period of time. At the same time, the output of the heater is gradually reduced to a low output. Furthermore, whether he temperature within the foot warmer or the output condition of the heater 1 holds a predetermined value or a predetermined output value reduced from the rated output or is under a varied unstable condition, is judged by a control process such as the temperature check of a control unit having a control circuit 10 within an external controller 9 or the secondary side voltage check of a current transformer. For example, when the output of the heater is of an output value reduced from the rated output of the heater or the condition of the temperature within the foot warmer is constant for a predetermined period of time, such a temperature control in performed as lowering it to a value which is slightly lower than the originally set temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application P The present invention relates to an electric kotatsu for heating a general household in winter.

Prior Art The temperature inside the electric kotatsu was controlled in the following manner. Generally, a heating unit consisting of a heater, blower, etc. is installed in the center of the back of the tower, but a temperature sensor is installed inside this heating unit to monitor the temperature inside the kotatsu. This temperature sensor monitors the
The heater was controlled and maintained at the desired temperature.

Heater control devices associated with this temperature sensor include those that use a thermostat to directly control the energization of the heater 1, and those that use a semiconductor sensor to measure the temperature and input to the heater using an electronic circuit such as a nine-phase control method. It was something to control. There are other methods such as controlling the air volume.

If you set the phase control method to a certain temperature scale and look at the temperature change inside the kotatsu and the change in the output of the heater after turning on the switch, all methods will produce a temperature as shown by the dotted line in Figure 2. Alternatively, the output characteristics were as shown in 3P.

In other words, when you turn on the switch, the heater and air blower operate, the temperature inside the kotatsu rises, and when the desired temperature is reached, the controller controls the input to the heater.
It worked to keep the temperature inside the kotatsu constant from then on.

Problems to be Solved by the Invention In the conventional technology as described above, the temperature of the electric kotatsu has a function to maintain the set temperature after turning on the switch and changing the temperature to the desired temperature. It was something like that.

Therefore, the temperature inside the kotatsu remains at the set temperature forever, regardless of whether or not someone is warming the kotatsu.

Therefore, it would be fine if there was always someone there to take the temperature, but in daily life there are many chances of the temperature being maintained at the set scale even without someone taking the temperature.

Especially when the temperature is set at a high temperature, it will be warm and comfortable when someone is there to take the heat, but maintaining a high temperature when there is no one to take the heat means high electricity bills and energy loss. In addition, high temperatures have adverse effects such as reducing safety and shortening the lifespan of each component.

Means to Solve the Problems In order to solve the problems seen in the conventional example, we installed a heat generating unit using an air blower at the bottom. When the kotatsu warms up, the temperature of the air flowing through this air path remains constant at the set temperature, and the output of the heater, which correlates to this temperature, also remains constant, making it easy for the person taking the heat to enter and exit the kotatsu. Pay attention to the fact that the temperature of the air flowing through this air path and the output of the heater will change when the heater is moving inside or outside the room. Depending on whether the output or temperature inside the kotatsu is constant or unstable, the temperature inside the kotatsu can be maintained or changed. A control circuit is also installed that controls the output to a certain level or lowers the temperature slightly when the temperature inside the kotatsu remains constant for a certain period of time.
This problem can be solved by P digits.

action With the above configuration, it is possible to detect whether there is a person taking heat.

The kotatsu temperature is further controlled, and its function is as follows.

When you turn on the power, the heater is energized, warming the inside of the kotatsu, and the temperature sensor monitors the temperature.

When the set temperature is reached, the heater is controlled to maintain the set temperature constant.

Here, the air inside the kotatsu is sucked into the heat generating unit by the blower, and is eventually blown out using the inside as an air path, so the air inside the kotatsu is easily stirred and the temperature inside the kotatsu is evened out.

At this time, by installing a temperature sensor in the air path, especially in the suction air path, the temperature inside the kotatsu can be accurately and more sensitively detected.

In other words, the temperature inside the kotatsu detected by the temperature sensor installed in the air passage is either constant, rising, falling, or changing up and down. The system determines the state of the heater's output and controls whether the temperature inside the kotatsu is maintained at the set temperature, lowered below the set temperature, or raised to the set temperature.

As a result, when there is no one taking the heat, the temperature of the kotatsu will eventually become constant at the set temperature, and the output of the heater, which correlates to this, will also be lower than the rated output and remain constant, so you can control it by lowering it slightly below the set temperature. The temperature is controlled to be lukewarm than the set temperature, and the person who takes the heat can enter and exit the kotatsu.
When the kotatsu is moving to collect heat, the temperature inside the kotatsu will drop or become unstable, and the corresponding heater output will also become unstable. Control to maintain temperature.

Example An embodiment of the present invention will be described below with reference to the drawings.

Reference numeral 1 denotes a lamp-shaped heater made of a rod-shaped quartz tube, which is formed on both sides of a blower device 27 P consisting of a fan 3 and a motor 4. 5 is a temperature sensor, which controls the temperature inside the kotatsu and is a signal source for controlling heater 1, and is a signal source for heater 1, blower 2, and temperature sensor 5.
It is installed in the air passage 6 of the suction port 61 part in the heating element unit Z consisting of the above. A suction port 61 is provided in the center of the guard 63 provided on the lower surface of the heating element unit 7.
An air outlet 62 is provided on the outer periphery of the air outlet. It is a tower with legs on each of the 8 corners.

A nine heating element unit 7 is attached to the center back surface.

(a) shows the flow of air in the heating element unit 7 portion by the blower 2. 81 Kefuton.

←) shows the air flow inside the kotatsu when it is operating as a kotatsu. Reference numeral 9 denotes a controller, which includes a control device 1) having a control circuit 10 for controlling the heater 1 to set the temperature inside the kotatsu using a signal from the temperature sensor 5.

The operation of the above configuration will be explained next.

The temperature inside the kotatsu using the temperature sensor 5 is controlled as follows. As shown in Figure 2, the kotatsu heater 1
When power is applied to the kotatsu, the temperature of the kotatsu rises and eventually reaches the set temperature. Along with this.

The output of the heater 1 is also gradually reduced to a low output. Furthermore, whether the temperature inside the kotatsu or the output state of the heater 1 is kept at a constant temperature, a constant output that is lower than the rated output, or is in an unstable state where it is changing, can be determined by external control. Control circuit 1 in controller 9
This is determined by control processing such as checking the temperature of the control device 1) having 0 or checking the secondary side voltage of the current transformer. When doing so, the temperature is controlled to be slightly lower than the initially set temperature.

The temperature sensor 5 is installed in the air passage 6 where it can most sensitively detect the temperature inside the kotatsu, and on the side of the suction port 61, so it can monitor the kotatsu temperature most accurately.

Effects of the Invention According to the present invention, the temperature of the kotatsu is controlled to always maintain a constant temperature as in the past. The temperature of the kotatsu is further controlled by determining whether it is in a constant output or constant temperature state.

The temperature inside the kotatsu is maintained at the set temperature, and the warmth during heating is the same as before, but there are no 9 people inside, and the temperature inside the kotatsu is already a constant output that is lower than the set temperature or the rated output of the heater. When held for a certain period of time,
Since the temperature of the kotatsu is lowered, there is no need to use wasted electricity to maintain a high temperature when 9 people are not in the room.
It saves energy.

Furthermore, it is safe because it automatically lowers the temperature of the kotatsu when no one is around, and it is a useful function when you forget to turn it off.

In order to determine whether someone is taking warmth or not, we monitor two characteristics: the temperature inside the kotatsu, which is detected by a temperature sensor, and the output of the heater, which is phase-controlled by a control circuit and changes almost continuously. Therefore, it is possible to accurately determine whether there is a person taking warmth.

0P Furthermore, by keeping an eye on these two characteristics.

The presence/absence determination can be speeded up, and the determination can be made moment by moment without having to carefully determine one characteristic.

[Brief explanation of drawings]

Fig. 1 is a sectional view of essential parts of an electric kotatsu showing an embodiment of the present invention, Fig. 2 is a characteristic diagram of temperature and output of electric kotatsu showing a conventional example and an embodiment of the present invention, and Fig. 3 is a diagram of the main parts of an electric kotatsu showing an embodiment of the present invention. FIG. 4 is a cross-sectional view of a main part of an electric kotatsu showing an entire embodiment of the invention, and FIG. 4 is a block diagram of a control device used in the electric kotatsu. 1. Heater, 2. Air blower. 5. Temperature sensor, 7 Heating unit. 10... Control circuit.

Claims (1)

[Claims] A heating element unit (7) consisting of an air blower (2), a heater (1), and a temperature sensor (5) that detects the temperature inside the kotatsu, and receives a signal from the temperature sensor (5) to control the heater (1). In an electric kotatsu consisting of a control circuit (10), the output of the heater (1) and the temperature inside the kotatsu are electrically monitored via a temperature sensor (5), and the output of the heater (1) is lower than the rated output. With reduced output,
Determine whether the constant output or the temperature inside the kotatsu is saturated at the set temperature, or whether the output of the heater (1) or the temperature inside the kotatsu is changing and unstable, and then adjust the output from the rated output. A control circuit (10) that controls the internal temperature of the kotatsu to be slightly lowered when the kotatsu is kept at a constant output or constant temperature for a certain period of time.
An electric kotatsu characterized by being equipped with.