| 摘要 |
<p>The position of a tape loop in a vacuum chamber is capacitively detected. The capacitive detector includes a flexible electrode that is deflected between a pair of walls parallel to a wall of a vacuum chamber in which the loop is formed by differential pressure in the chamber and by the pressure of a vacuum source having a pressure between the two pressures in the vacuum chamber. Between the flexible electrode and a stationary electrode is a fixed, solid dielectric. The wall includes plural apertures forming separate fluid flow paths. The vacuum source includes a partition with a plurality of apertures forming separate fluid flow paths. The apertures of the wall and partition are aligned and positioned in a direction between opposite ends of the vacuum chamber. The vacuum chamber wall is electrically grounded and an electrical insulator is positioned between an end of the flexible electrode adjacent the wall to maintain the flexible electrode electrically insulated from and a different potential from the grounded wall.</p> |
