Abstract: In a brushless DC motor comprising a stator provided with a plurality of coils, a rotor magnet magnetized so as to possess a plurality of magnetic poles and rotatably disposed as opposed to the coils of the stator, and a magnetic sensor which detects the magnetic poles of the rotor magnet, in which the electric current supplied to said coils of respective phases is controlled based on a detection signal from said magnetic sensor so that the rotor magnet is rotationally driven, the magnetic sensor comprises in combination a giant magnetoresistive element disposed as opposed to the rotor magnet and a magnet disposed on a rear side of the giant magnetoresistive element. The giant magnetoresistive element is formed of a magnetic particle dispersion type giant magnetoresistive material, an artificial lattice type giant magnetoresistive material, or a colossal magnetoresistive material.

Abstract: A detector for the rotational angle of a motor and a small brushless or stepping motor having the detector built therein are disclosed. A sensor probe of the detector is provided with a wire configuration comprising a giant magnetoresistive element (sensor element) enabled to read a change in magnetic field up to at least 10 kOe, a first sensor lead and a second sensor lead connected one each to the opposite terminals of the magnetoresistive element, and an insulating layer interposed between the two sensor leads. The sensor probe of the detector is disposed inside a motor housing as approximated closely to the magnetic teeth of a rotor of the motor. The giant magnetoresistive element is formed of a magnetic particle dispersion type giant magnetoresistive material, an artificial lattice type giant magnetoresistive material, or a colossal magnetoresistive material.

Abstract: A detector for the rotational angle of a motor and a small brushless or stepping motor having the detector built therein are disclosed. A sensor probe of the detector is provided with a wire configuration comprising a giant magnetoresistive element (sensor element) enabled to read a change in magnetic field up to at least 10 kOe, a first sensor lead and a second sensor lead connected one each to the opposite terminals of the magnetoresistive element, and an insulating layer interposed between the two sensor leads. The sensor probe of the detector is disposed inside a motor housing as approximated closely to the magnetic teeth of a rotor of the motor. The giant magnetoresistive element is formed of a magnetic particle dispersion type giant magnetoresistive material, an artificial lattice type giant magnetoresistive material, or a colossal magnetoresistive material.