| 摘要 |
PROBLEM TO BE SOLVED: To set the temperature of an electromagnetic induction heating type fixing device to arbitrary high temperature even during use of magnetic shunt alloy by making it possible to select exhibition of a self-temperature-control function by making a demagnetizing function selectable. SOLUTION: The Curie point of a magnetic shunt layer 3C is made high, and a magnetic core 3H and a demagnetizing material 3K which is sectioned in a semicylindrical shape are provided inside it, the demagnetizing material 3K being made rotatably in the magnetic shunt layer 3C together with the magnetic core 3H. When a function of the demagnetizing material 3K is enhanced, the demagnetizing material 3K is disposed closely to the coil 2 and then the magnetic shunt alloy constituting the magnetic shunt layer 3C loses magnetism to become a nonmagnetic body, thereby exhibiting a high demagnetizing function. The magnetizing material 3K is put away from the coil 2 and then the demagnetizing function is not exhibited since the temperature T of a magnetic shunt alloy layer constituting the magnetic adjusting layer 3C is higher than the Curie temperature Tc and no induced magnetic flux is produced by the demagnetizing material 3K although induced magnetic flux from the coil 2 is transmitted through the magnetic shunt layer 3C, so that the magnetic shunt alloy does not lose the magnetism to remain as a magnetic body. COPYRIGHT: (C)2008,JPO&INPIT |
