| 摘要 |
PROBLEM TO BE SOLVED: To improve temperature distribution and avoid an increase in the outer diameter or the weight of a coil part. SOLUTION: An inner peripheral side heating coil 1b and an outer peripheral side heating coil 1a are arranged and installed so as to be separated by a prescribed distance, and an inner peripheral side heating coil 1c of a second stage is arranged and installed so as to be wound up in plural stages together with the inner peripheral side heating coil 1b, and a heating coil 1 in which an outer peripheral side heating coil 1d of the second stage is arranged and installed so as to be wound up in plural stages together with the outer peripheral side heating coil 1a, the central part magnetic material 6 arranged and installed nearer to the inner periphery of the inner peripheral side heating coil 1b and the inner peripheral side heating coil 1c of the second stage over the stage direction, and a lower face magnetic material 7 which is arranged and installed downward of the heating coil 1 and whose inner peripheral side end part makes contact or is adjacent to the central part magnetic material 6 are equipped. |
