Patent ID: 7307415

Claim:
A contactless angular position sensor comprising: a rotatable shaft, a first magnet connected for rotation responsive to rotation of the shaft, the first magnet establishing a first continuously varying magnetic field as the shaft rotates; a first gear train having an input connected for rotation with the first magnet and an output responsive to rotation of the input according to a first rotational ratio therebetween; a second magnet connected for rotation with the output of said gear train, the second magnet establishing a second continuously varying magnetic field as the output of the gear train rotates; first and second magnetic field sensors positioned to sense the first and second continuously varying magnetic fields, respectively, of said magnets as they rotate, said magnetic field sensors having respective output signals indicative of the magnetic fields sensed; one of said output signals being course indicative of the angular position of the shaft and the other of said output signals being fine indicative of the angular position of the shaft; and a signal processing block receiving said output signals and operative to determine an indication of the angular position of said magnets therefrom, and to provide a resultant signal indicative of the rotational angle of the shaft as a function of the rotational ratio of the gear train and the angular positions of the magnets.