Patent ID: 6892587
Filing Date: 2005-05-17
Classification: F16C,G01P,H02K

Abstract:
1. A rotation detecting device which comprises: a rotatable member rotatably supported on a non-rotatable member; an electric power generator for generating an electric power by a relative rotation between the non-rotatable member and the rotatable member; a transmission device for transmitting wireless at least one of a rotational speed detection signal outputted by the electric power generator and an output signal from a sensor that operates using as an electric power source the electric power generated by the electric power generator, said transmission device being of an annular configuration; and a sealing member for sealing a space delimited between the non-rotatable member and the rotatable member; said electric power generator comprising a multi-pole magnet assembly having a plurality of alternating magnetic poles arranged in a circumferential direction, and a magnetic ring assembly accommodating a coil and confronting the multi-pole magnet assembly; said wireless transmission device being disposed axially outwardly, but adjacent to the magnetic ring assembly of the electric power generator; said sealing member being mounted on the wireless transmission device and having a lip member slidingly engaged with a seal contact area defined in the rotatable member; and said magnetic ring assembly and the multi-pole magnet assembly of the electric power generator confronting with each other at a location inwardly of the sealing member.