| 摘要 |
PURPOSE:To reduce power loss and enable a non-load state to be surely detected by holding reference value and load value at the time of finishing continuous time only until a switching means turns ON in the next working period. CONSTITUTION:A substance to be heated is heated by making the substance to be heated to generate electromagnetic induction while generating resonance voltage according to ON and OFF of a switching means corresponding to the operation of the switching means. When there exists no substance to be heated, a non-load detection means 21 compares reference value with load value so as to detect a non-load state. Further, the holding means 25 and 35 surely hold the reference value and the load value at the time of finishing continuous time of electromagnetic induction during the period until the switching means turns ON at a next period. Thereby, crossing of the load value and the reference value is not generated in the stop control period of a heating means 7 in the state of heating the substance to be heated, further, in the operation control period of the heating means 7, a non-load detection means 21 surely detects a nonload state. |
