| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a physical quantity measuring apparatus capable of easily obtaining superior measurement signal, without having to adjust sensor mounting position, and to provide a magnetic levitation apparatus equipped with the physical quantity measuring apparatus and a vacuum pump. <P>SOLUTION: A sensor for measuring a physical quantity, based on high-frequency voltage amplitude-modulated by the inductance change of a coil, is adjustable in sensor sensitivity, without requiring adjustment of the mounting position of a coil or its core, by providing the coil with an adjusting means for frequency characteristics of modulated high-frequency voltage or the frequency of high frequency voltage. A differential means is provided for outputting the difference between a measurement signal and an adjustable reference value signal. Power consumption is thereby reduced, and a low saturation amplifier can be used. Furthermore, the adjusting means is arranged at a magnetic bearing or a mechanism part of the vacuum pump to thereby improve the interchangeability of the mechanism part and a controller. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
