| 摘要 |
<p>A rotatable capacitance sensor (16) for detecting film thickness of a moving film web, the rotatable sensor (16) having a capacitive element (18) comprising a plurality of capacitive plates arranged to contact the moving web film, the capacitive element (18) electrically connected to projecting shaft ends (24, 28) of the rotatable sensor (16) via wires (42, 46), resilient conductors (32, 34) urged against the respective shaft ends (24, 28), and an electrical shield overlaying the resilient conductors and the rotatable shaft, to electrically isolate capacitance variations caused by shaft wobble from the surrounding housing. The position of the rotatable sensor 16 may also be indexed using embeded magnet 27 and pick-up 31. <IMAGE></p> |
