Patent ID: 6871554

Claim:
Device for determining the absolute angular position of a turning device with respect to a fixed structure, where said device includes: an encoder adapted for rotation together with the turning device, said encoder includes a main multipolar track and a top turn track which are concentric, said top turn track includes M angular distributed singularities; a fixed sensor arranged with regard to a gap distance of the encoder including at least three sensing elements where at least two are positioned with regard to the main multipolar track so as to deliver two periodic signals S 1 , S 2 in quadrature and at least one is positioned with respect to the top turn track so as to deliver an electrical signal S 3 , the sensor includes an electronic circuit capable of delivering, starting from the signals S 1 , S 2 and S 3 , two squared digital position signals (A, B) in quadrature which are representative of the angular position of the turning device and one top turn signal (C) in the form of M pulses per revolution of the encoder; one processing device of the signals (A, B, C) which includes an appropriate means of counting, to determine, starting from an initial position, variations of the angular positions of the encoder; in which the M singularities are angularly distributed so that the top turn signal (C) is arranged so as to define, together with the signals (A, B), the binary sequences which are each representative of an absolute angular position of the encoder, the processing device includes means for updating the initial position which, at the time of detecting a binary sequence, are suitable to assign, with regard to the initial position, the absolute angular position value associated with each binary sequence.