| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an active magnetic shielding device capable of solving the problem, wherein when a compensation coil is large, a heavy drive current is required to pass to the compensation coil at all times, and low power consumption of the active magnetic shielding device in conventional methods, or low power consumption for the large active magnetic shielding device cannot be attained. <P>SOLUTION: The active magnetic shielding device 1 includes magnetic materials 101, 102; magnetic field compensation coil 201, 202 arranged contacting magnetic materials 101, 102; a magnetic sensor 300 for measuring an environmental magnetic field; and a drive signal control section 400 for controlling the drive signal Ib which drives magnetic field compensation coil 201, 202, based on a measuring signal Vb from the magnetic sensor 300. When variation in the measuring signal Vb lies within a prescribed range, the drive signal Ib is turned off by the drive signal control section 400, after an interval required for magnetizing the magnetic materials 101, 102. <P>COPYRIGHT: (C)2011,JPO&INPIT |
