Patent ID: 7898245

Claim:
A magnetic encoder equipped with a disc-shaped or ring-shaped permanent magnet attached to a rotor and magnetized in one direction perpendicular to an axial direction of the rotor, a magnetic field detecting element attached to a stator so as to face the permanent magnet via a gap, and a signal processing circuit for processing a signal from the magnetic field detecting element, characterized in that the magnetic field detecting element comprises Hall sensors of phase A 1 , phase B 1 , phase A 2 and phase B 2 sequentially arranged at intervals of 90 degrees and Hall sensors of phase C 1 , phase D 1 , phase C 2 and phase D 2 respectively arranged at positions α degrees away from the Hall sensors of phase A 1 , phase B 1 , phase A 2 and phase B 2 , wherein α=360/N or α=180/N (N is an odd number of 3 or above), and output terminals of the Hall sensors of phase A 1 , phase B 1 , phase A 2 and phase B 2 and output terminals of Hall sensors of phase C 1 , phase D 1 , phase C 2 and phase D 2 are connected in parallel, respectively.