JP2956868B2 - Electric carpet control equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric carpet and, more particularly, to control of energization of a heater.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram of a conventional electric carpet. Reference numeral 1 denotes an AC power supply. Connected to the second input terminal. The sensor 3 is connected between the connection point between the variable resistor 2 for temperature adjustment and the rectifier diode 4 and the ground. A reference voltage 6 is connected to a first input terminal of the comparator 7. The output of the comparator 7 is connected to a first relay driver 8, and the output of the first relay driver 8 is connected to a heater 9.
The sensor 3 is laid in parallel with the heater of the electric carpet, and the primary side line and the secondary side line of the sensor 3 are provided via an insulating layer. The temperature change of the electric carpet heated by the heater 9 is detected by the sensor 3 and output as a change in resistance value. That is, the resistance value of the sensor 3 decreases as the temperature increases, and increases as the temperature decreases. A resistance value determined by setting the variable resistor 2 to a desired temperature and a detection voltage determined by the resistance value detected by the sensor 3 are input to the second input terminal of the comparator 7 via a series circuit of the rectifier diode 4 and the adjustment resistor 5. You. The comparator 7 compares the input reference voltage 6 with the detection voltage (second input terminal), and outputs an output when the detection voltage is higher than the reference voltage 6,
If it is low, the output signal is stopped. First relay driver 8
When the comparator 7 is outputting, the relay is driven to energize the heater 9, and when the output of the comparator 7 is stopped, the relay is turned off, and the energization to the heater 9 is stopped. Therefore, when the electric carpet starts, as shown in FIG.
The detection voltage starts from the point a, at which point the reference voltage 6
Since it is higher, the heater 9 is turned on and the electric carpet starts to increase in temperature. When the detection temperature 11 of the sensor 3 reaches the set temperature 13, the detection voltage becomes equal to the reference voltage 6 (d
), The first relay drive section 8 operates to cut off the power supply to the heater 9. Therefore, the temperature of the electric carpet starts to decrease, the sensor detection temperature 11 decreases, and the detection voltage starts to increase. Hereinafter, the connection / disconnection of the power supply to the heater 9 is similarly repeated. On the other hand, the surface temperature of the electric carpet, that is, the surface temperature 12 on which a person sits, rises later than the rise of the sensor detection temperature 11, and at a point e after a required time, the set temperature 13
To reach. Since the surface temperature 12 at which the person sits has a considerable temperature difference between the point d and the point e after the required time, even if the temperature is appropriate at the start, it becomes uncomfortable after the required time. In order to solve this, the set temperature 13
Setting, there was a problem such as not getting warm at the start.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and increases the set temperature of an electric carpet at the start and gradually lowers the set temperature automatically over time. The purpose of this is to make the surface temperature at which a person sits constant at all times.

[0004]

In order to solve the above-mentioned problems, according to the present invention, one end of an AC power supply is connected to a second input terminal of a comparator through a series circuit of a power switch, a variable resistor, a rectifier diode and a resistor. , The other end is grounded, a sensor is connected between the connection point of the variable resistor and the rectifier diode and ground, a reference voltage is connected to a first input terminal of the comparator, and a first relay driving unit is output by an output signal of the comparator. A plurality of resistors are connected in parallel between the second input terminal of the comparator and the ground, and a relay for switching the resistors and turning on the power switch are provided. A power start detection unit for detecting, a timer for counting time by a detection signal of the power start detection unit, a storage unit for storing a plurality of time data, And a control unit timer outputs the detected control signal to match the time data of time and the storage unit counted, constituted by the second relay driver for driving said relay the control signal of the same control unit.

[0005]

According to the above arrangement, the detection section detects that the power switch of the electric carpet is turned on, and counts the time by the timer. When the timer time reaches the first time data value stored in the storage unit, the control unit drives the second relay driving unit to switch the relay, and connects the first resistor to the second input terminal of the comparator. Decrease the set temperature. Then, the counting of the timer is continued, and when the time of the timer reaches the second time data value in the storage unit, the control unit drives the second relay driving unit to switch the relay, and the first resistance of the second input terminal of the comparator. Is switched to the second resistor, and the set temperature is changed to a lower value. By the above operation, the surface temperature of the electric carpet is kept constant.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of the electric carpet control device of the present invention, FIG. 2A is a waveform diagram of a reference voltage and a detected voltage of the electric carpet control device of the present invention, and FIG. FIG. 4 is a diagram showing a change over time in the temperature of the control device of the carpet, and those having the same functions as those in FIG. In the figure, the relay 19
Is connected to the second input terminal of the comparator 7 via the resistor 20, the third movable terminal is connected to the second input terminal of the comparator 7 via the resistor 20, and the fixed terminal is grounded. The resistance of the first resistor 20 is set smaller than that of the second resistor 21. Reference numeral 18 denotes a power start detection unit, and a power switch 1
It is detected that the electric carpet is turned on by inputting 0. Reference numeral 15 denotes a timer for counting time. A storage unit 16 stores a plurality of time data. 19 is a relay for switching circuits. Reference numeral 14 denotes a second relay driving unit,
9 is driven and switched. A control unit 17 controls the power start detection unit 18, the timer 15, the storage unit 16, and the second relay driving unit 14.

In the above configuration, the power start detection unit 18 detects when the power switch 10 of the electric carpet is turned on, and the control unit 17 activates the timer 15 by the detection signal of the power start detection unit 18 to count. Let it start. When the time counted by the timer 15 reaches the first data time (point b in FIG. 2) stored in the storage unit 16, the control unit 17
Sends a signal to the second relay drive unit 14. The second relay driving section 14 drives the relay 19 and grounds the first resistor 20 by selecting the terminal of the first resistor 20. As a result, the load on the second input terminal of the comparator 7 increases, and the detected voltage value decreases accordingly. This apparently means that the reference voltage value has moved to the higher level 24, which means that the set temperature 13 has been set to the next lower temperature 22. Subsequently, the timer 15 counts the time, and when the time reaches the second data time (point c in FIG. 2) stored in the storage unit 16, the control unit 17 sends a signal to the second relay driving unit 14. The second relay driving section 14 drives the relay 19 and grounds the second resistor 21 instead of the first resistor 20. As a result, the load on the second input terminal of the comparator 7 becomes larger, and the reference voltage value becomes higher at level 2.
This means that the set temperature 13 has been set to a lower temperature 23. When the power switch 10 of the electric carpet is turned on, energization of the heater 9 is started, the sensor detection temperature 11 rises, and when the point b is reached, the apparent set temperature becomes one step lower than the temperature 22, and the setting is performed. The connection / disconnection of the power supply to the heater 9 is repeated based on the temperature 22. Furthermore, when time elapses and the point c is reached, the apparent set temperature becomes further lower by 23, and the connection / disconnection of power supply to the heater 9 is repeated based on the set temperature 23. As a result, the surface temperature at which a person sits 12
Since the temperature changes almost at the same temperature as that at the start, the temperature difference between when the power is turned on and after a lapse of time is reduced.

[0008]

As described above, according to the present invention, the temperature difference on the surface of the electric carpet after the start of use of the electric carpet and after a lapse of time can be reduced, and low-temperature burn can be prevented. Discomfort due to such a high temperature difference is eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a control device for an electric carpet of the present invention.

FIG. 2 is a waveform diagram of the electric carpet control device of the present invention.

FIG. 3 is a block diagram of a conventional electric carpet.

FIG. 4 is a waveform diagram of a conventional electric carpet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply 2 Variable resistance for temperature adjustment 3 Sensor 4 Diode 5 Resistance 6 Reference voltage 7 Comparator 8 First relay drive unit 9 Heater 10 Power switch 11 Sensor detection temperature 12 Surface temperature on which a person sits 13 Set temperature 14 Second relay drive unit 15 Timer 16 Storage unit 17 Control unit 18 Power start detection unit 19 Relay 20 First resistor 21 Second resistor 22 One step lower temperature 23 One step lower temperature 24 Higher reference voltage value 25 Higher reference voltage value 26 Power switch

Claims (1)

(57) [Claims] An AC power source is connected at one end to a second input terminal of a comparator via a series circuit of a power switch, a variable resistor, a rectifier diode and a resistor, and the other end is grounded to connect the variable resistor and the rectifier diode. In an electric carpet, a sensor is connected between a point and a ground, a reference voltage is connected to a first input terminal of the comparator, and a first relay driving unit is driven by an output signal of the comparator to control energization of a heater. A plurality of resistors connected in parallel between a second input terminal of the comparator and ground; a relay for switching the resistors; a power start detection unit for detecting the turning on of the power switch; A timer for counting the time by a signal, a storage unit for storing a plurality of time data, and one of the time counted by the timer and the time data in the storage unit. A control device for an electric carpet, comprising: a control unit that detects a fault and outputs a control signal; and a second relay driving unit that drives the relay by the control signal of the control unit.