| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve usability by excluding inverter operation at an unintended drive frequency. <P>SOLUTION: For induction heat of a load 5 in a state in which initially determined drive frequencies of first and second switching means 4a and 4d change as the load 5 changes in material or shape determined at the start of the heating, material determination means 10 determines the material of the load again if ambient temperature or temperature change, which is detected by temperature detecting means 11 provided on a printed wiring board 13, of the first and second switching means 4a and 4d, a radiator 12, a conductor foil connected to terminals of the first and second switching means 4a and 4d, or the printed wiring board 13 exceeds a predetermined threshold when the first and second switching means 4a and 4b are made to generate turn-on currents to make operation ready, thereby obtaining drive frequencies of the first and second switching means 4a and 4d suitable to the changed electric state of the load 5. <P>COPYRIGHT: (C)2012,JPO&INPIT |
