JPS63213727A - Heating apparatus - Google Patents

Abstract

PURPOSE:To avoid the re-conduction of a heating apparatus when the failure of power supply occurs after a timer operates to cut power off, by a method wherein a power control element for temperature control is put ON or OFF by the output of a power switch condition detecting circuit and the output of a single pulse generating circuit, which outputs the pulse when the power switch is switched from OFF to ON, and the condition is indicated. CONSTITUTION:When a timer 7 is operated and a set time has come, the output of the timer 7 is inputted into a time-up flip flop 9 and the operation of the timer 7 is stopped. 'OFF' is indicated on an indicator LCD27 by the output of a frequency divider 6 and the output of an AND gate 25 and a transistor 35 is operated to put a relay controlling transistor 117 OFF. When the failure of power supply has occurred under the condition of a power switch ON and re-conduction is effected, all flip flops are reset by the reset signal A of a reset signal generating circuit; therefore, the indication of 'OFF' is shown on the indicator LCD27 and the relay driving transistor 117 is turned OFF.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to heating appliances such as electric blankets or electric carpets.

BACKGROUND OF THE INVENTION When using a conventional heating appliance of this type, for example a carpet, when electrical timer control is performed, when the timer setting time arrives, the temperature control power control element that controls the energization of the heating element is turned off. After the power is turned on, there is a power outage, and when the power is turned on again, the device is turned on, or the temperature setting is set to zero, and all displays are turned off.

Problems to be Solved by the Invention However, in the above-mentioned conventional technology, the carpet should be turned off after the timer is activated, but the carpet is turned on due to a power outage, giving the user a sense of anxiety.

In addition, in order to eliminate this feeling of anxiety, the system is configured so that if there is a power outage after the timer is activated, the temperature setting will be set to zero when the power is turned on again, and all displays such as the pilot lamp will be turned off after the timer is activated. However, when the power is turned on again, or when the power switch is turned on and the power plug is connected to the power outlet for the first time, there is no display or operation, so the user may think that it is malfunctioning. I sometimes made mistakes. In this case, there was a major problem in that in order to operate normally, the power switch had to be turned off, then turned on again, and then the temperature setting had to be increased from zero to the desired setting.

Means for Solving the Problems In order to solve the above problems, the present invention provides an output of a power switch state detection circuit that detects whether the power switch is on or off, and a power switch state detection circuit that detects whether the power switch is turned on or off. hour 1
The power control element for temperature control is turned on or off by the output of a single pulse generation circuit that generates a pulse, and a control circuit is added to display this state.

Function: With the above-described configuration, the present invention provides a sense of security to the user without having to turn on the power again in the event of a power outage after the power switch is turned on and the timer operates and the power is turned off. Also, when the power switch is on and the power plug is connected to the power outlet, the off state is displayed, so there is no mistaking it as a malfunction.

Embodiment FIG. 1 is a circuit diagram showing an embodiment of the heating appliance of the present invention. In FIG. 1, 1 is a power plug, 2 is a power transformer or step-down resistor, and a step-down rectifier circuit that rectifies its output.
3 is a stabilized power supply circuit, and 4 is a reset signal generation circuit that outputs a reset signal when the output of the stabilized power supply circuit decreases, that is, when the power plug 1 is unplugged from the power outlet or during a power outage. 5 is an oscillator such as an astable multivibrator, 6 is a frequency divider, and L is an indicator.
A rectangular wave is supplied to the segment terminal and common terminal of the CD27. It is also a frequency divider at the front stage of the timer 7 (which is also a divider, but will be referred to as a timer hereinafter).

The power switch consists of a switch 50-1, 50-2,
They are linked internally. When the power switch is turned off, the switch 50-1 has contacts 50-1-2 and 50-1.
-3 is connected and the terminal 501-2 is at the GND level of the circuit, so the output of the OR gate 11 is Low (
(described below), all logic IC outputs are reset, the display LCD 27 becomes blank, and the contacts 50-2-1 and 50-2-2 of the switch 50-2
Since the relay 116 is open, the power to the relay 116 that controls the energization of the heating element 119 is cut off, so that everything becomes inactive.

When the power switch is turned on from this state, switch 60-1
The contacts 50-1-2 and 50-1-1 are connected, and current begins to flow through the capacitor 16 and resistor 15 until the capacitor 16 is fully charged, so the signal waveform diagram at each part shown in FIG. A switch state signal C and a one-shot pulse signal B are generated when the power switch is turned off. 13 and 14 are resistors, and when the power switch is turned off, the resistor 13 sets C to the GND level, and the resistor 14 is for discharging the capacitor 16.

17.36.20 is an inverter t) -Haha A/
The signal B is the output of the inverter 17. 19.21 is a NOR gate, which is input to the T terminal of the switch state detection flip-flop (hereinafter referred to as switch state detection FF) 8 and the R terminal of the reset terminal, and the output d becomes L and AN
The DNO gate 25, the OR gate 24, and the exclusive OR gate 26 show the display LCD 27.
OFF” is not displayed. Also, the base of the transistor 35 is also L.
Therefore, the relay driving transistor 117 is controlled by the output of the temperature control comparator 112.

At this time, when the timer button 33 is pressed, the output of the switch pulse generation circuit a1 generates a switch pulse signal as shown in the signal waveform diagram of each part shown in FIG. ，
30, it is input to the timer button flip-flop (hereinafter referred to as timer button FF) 100T terminal, and this Q output becomes H, and the timer 7 starts operating by the output of the ANDNO gate. When the set time comes, the output of the timer 7 is input to the set terminal S of the time-up flip-flop (hereinafter referred to as time-up FF) 9, and the Q output becomes H.
, the Q output becomes L, the output of exclusive 0R30 is input to the T4 terminal of the timer button FF10, the Q output of the timer - button FFl0 becomes L, the output of the AND gate 12 becomes L, and the operation of the timer 7 is stopped. .

Also, since the output Q of the time-up FF 9 becomes L, the switch state detection FF is activated by the output of the NOR gate 19.
8's output becomes H, and the output of AND gate 23 becomes )I,
The output of the OR gate becomes H and is ANDed with the output of the frequency divider 6.
The output, that is, the output of the AND gate 25 causes the display LCD2
“Off” is displayed at 7. Further, the transistor 35 operates to turn off the relay control transistor 117 regardless of the output of the temperature control comparator 112.

When the power switch is unplugged from the outlet for more than 1 minute and then plugged back in, or when the power is turned on again after a power outage, the power switch is turned off by the reset signal A of the reset signal generation circuit.
Since F is reset, the 6th output of the switch state detection FF8 becomes H, and the display LCD 27 shows "
"OFF" appears and relay drive transistor 117 is turned off.
shall be.

100 is a carpet temperature control circuit; 102.1
04.106.110.113.115 is a resistance,
107 and 108 are capacitors. 105.109,
114 is a diode.

103 is a temperature detection sensor. 118 is relay 11
This is the 6th point of contact. Day 1 is a temperature film constant variable resistor.

When the transistor 35 is OFF, the impedance change of the humidity detection sensor is extracted as a voltage change by components 102 to 107, a reference voltage is generated by 108 to 111, and inputted to the temperature control comparator, and the relay is activated by the comparator output. The drive transistor 117 is operated and the relay 116 is operated to control the energization of the heating element 119. Effects of the Invention As described above, according to the present invention, when there is a power outage while the timer is out of operation, the power is re-energized. Even if the switch is turned off, it will turn off again and the "off" state will be displayed, so it is safe and gives the user a great sense of security, and is extremely useful in practice.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a heating appliance according to an embodiment of the present invention, and FIG. 2 is a signal waveform diagram of each part of FIG. 1. 50-1.50-2...Switch, 8...
...Switch state detection FF, 27...Display device,
100...Temperature control circuit, 116...
Relay, 119...Heating element.

Claims (4)

[Claims] (1) A power switch state detection circuit that detects the state of the power switch, and when the power switch is turned on from off,
A single pulse generation circuit that generates a single pulse, a control circuit that turns on or off a power control element for temperature control based on the output of the power switch state detection circuit and the output of the single pulse generation circuit, and a temperature control circuit. A heating appliance characterized by having a heating element. (2) The heating appliance according to claim 1, wherein the control circuit includes a display device and a display circuit for indicating an on or off state. (3) The heating appliance according to claim 2, which displays the characters "off" or "on" as a display. (4) The heating appliance according to claim 2, which has a blinking indicator.