| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a detector for a rotor having detection elements with their temperatures not exceeding their respective operable temperatures, with facilitated positional adjustment of the elements, and not requiring disposing the elements in at least two positions. SOLUTION: Whether the rotor exists or not is judged and the rotational speed of the rotor is measured by observing a change in electric capacity between a dielectric element so provided on the rotor as to be decentered by a prescribed distance from its axis of rotation and a conductor provided on a holding mechanism for holding the rotor and in a position confronting the dielectric element on the rotor.</p> |
