INDUCTION HEATING APPARATUS

To provide an induction heating apparatus capable of heating an inner side and an outer side of a heated material with good balance.SOLUTION: An induction heating apparatus 10 comprises: a first coil 14 provided inside of an inner peripheral surface 12a of a cylindrical heated material 12 and its extension surface 12ax, and wound along a direction of a shaft J of the heated material 12; and a second coil 16 provided at an outer side of an outer periphery surface 12b of the heated material 12 and its extension surface 12bx, and wound along the direction of the shaft J. The first coil 14 and the second coil 16 are connected in series, and an AC current I is supplied by one inverter 20. A phase of a magnetic flux generated when a current flows in the first coil 14 and the second coil 16 becomes the same in the heated material 12. A shaft direction length A1 of the first coil 14 is equal to a shaft direction length H1 of the inner peripheral surface 12a or larger, and a shaft direction length A2 of the second coil 16 is equal to a shaft direction length H2 of the outer periphery surface 12b or larger.SELECTED DRAWING: Figure 2 【課題】被加熱物の内側と外側とをバランスよく加熱することのできる誘導加熱装置を提供する。【解決手段】誘導加熱装置１０は、筒状の被加熱物１２の内周面１２ａとその延長面１２ａｘの内側に設けられ、被加熱物１２の軸Ｊの方向に沿って巻回された第１コイル１４と、被加熱物１２の外周面１２ｂとその延長面１２ｂｘの外側に設けられ、軸Ｊの方向に沿って巻回された第２コイル１６とを備える。第１コイル１４と第２コイル１６とは直列に接続され、１つのインバータ２０によって交流電流Ｉが供給される。第１コイル１４と第２コイル１６とは電流を流した際に発生させる磁束の位相が被加熱物１２内で同相となる。第１コイル１４の軸方向長さＡ１は、内周面１２ａの軸方向長さＨ１と等しくまたはそれ以上であり、第２コイル１６の軸方向長さＡ２は、外周面１２ｂの軸方向長さＨ２と等しくまたはそれ以上である。【選択図】図２