| 摘要 |
PURPOSE: To eliminate necessity for a cable between itself and a heating device by connecting a coil of detecting magnetic flux generated by a heating coil in parallel to a display part of one set or more wherein a resistor, Zener diode and a light emitting diode are connected in series. CONSTITUTION: A display circuit 2 is constituted by parallelly connecting one set or more, for instance, three sets of luminous parts 3a to 3c, to be connected to a coil 1 of detecting magnetic flux generated by a heating coil. In each luminous part, resistors 4a to 4c, Zener diodes 5a to 5c and light emitting diodes 6a to 6c are connected in series. When voltage generated in the coil 1 exceeds Zener voltage of the diodes 5a to 5c, light is emitted in the diodes 6a to 6c. Because each Zener voltage is set to a value increased stepwise, a diode of emitting light is different in accordance with an output condition of a heating device, to provide four stages of light emitting displays including in the case of not emitting at all in all the diodes. In this way, the circuit 2 is simply constituted by only a passive element, further to eliminate necessity for connection to the heating device, so as to enhance reliability. |
