Position detector.

摘要

A position detector which provides improved reference position detecting precision by stabilizing the output signal from magnetoelectric transducers in a reference position part. A rotor (2) has a magnetized surface (5) alternately provided with different magnetic poles and a reference positional part (5a) in which magnetic poles provided on the magnetized surface (5) are partly omitted. A rotational angle sensor (6) has MR elements (7A and 7B) laid out thereon in opposition to the magnetized surface (5) of the rotor (2) to output the voltage signal VS according to the magnetic field intensity in the magnetized surface (5) due to the rotation of the rotor (2). A waveform processing circuit (11) and a pulse signal processing signal (12) shape the waveform of the voltage signal (VS) from the rotational angle sensor (6), and also generate the rotational angle pulse signal (Ne) and a reference position pulse signal (G) according to the waveform reforming signal. The reference positional part (5a) is arranged so that the magnetic field intensity therein can be within the saturation magnetic field region of the Mr elements (7A and 7B). <IMAGE>