| 摘要 |
PROBLEM TO BE SOLVED: To provide an electromagnetic induction cooker prevented from such a hindrance of cooking that the output of an inverter circuit is not stopped caused by non-detection of a pot-less state, by setting an optimum period for detecting the pot-less state against the user's way of usage (shaking or frequent exchanges of the pot). SOLUTION: The electromagnetic induction cooker comprises a phase difference detecting circuit outputting a phase difference detection signal by detecting the phase difference between output voltage and output current of the inverter circuit, and a pot detection circuit determining that the pot is not put on the heater when the value of the phase difference detection signal is higher than a phase difference determining signal, and stopping the drive of an inverter driving circuit and stopping the supply of high frequency current by outputting the pot-less state detection signal. On heating the pot put on an induction heating coil by electromagnetic induction, a time-corresponding pot detection determining circuit stops the drive of the inverter driving circuit when the pot-less state detection signal is output for a period longer than the pot-less state detection judging period, and drives the inverter driving circuit when the pot-less state detection signal is output for a period shorter than the pot-less state detection determing period. The time-corresponding pot detection determining circuit is installed between the pot detection circuit and the inverter driving circuit. COPYRIGHT: (C)2005,JPO&NCIPI |
