| 摘要 |
PURPOSE:To obtain a rotation detector whose output voltage never varies even if a rotating speed varies by using a couple of thin film magneto-resistance elements which are arranged facing magnets for rotation detection having prescribed pitch and applied with a bias magnetic field. CONSTITUTION:A couple of thin film magnetoresistance elements 8A and 8B formed in folded pattern are installed facing magnets 4 for rotation detection at the outer circumference of a rotor in such a way that their interval T is nearly equal to the pitch of the magnets. Those elements 8A and 8B are applied with the bias magnetic field through a bias magnet 10, and a magnetic field produced by a main magnet as the rotor rotates operate on the elements 8A and 8B opposite to each other around a bias point as a center. Then, a rotation detection waveform which never varies in voltage level while corresponding to only an angle of rotation according to the rotation of the rotor through the magnet 4 is outputted through the elements 8A and 8B. |
