ELECTRIC MOTOR

摘要

An electric motor 1 includes: a shaft 3 formed of a magnetic member; a rotor 5 and a sensor target 21 that rotate integrally with the shaft 3; stators 7, 8 with an armature winding 6 and by its energization, generating a rotating magnetic field; a field magnet 9 sandwiched by the stators 7, 8 to magnetize the rotor 5; and a rotation sensor 20 placed in the side of the stators 7, 8 to determine a rotational position of the shaft 3. The rotation sensor 20 incorporates a sensor magnet that generates a magnetic field passing across a sensor target 21 and a sensor element that detects a magnetic flux of the sensor magnet that varies according to a rotational position of the sensor target 21, and is placed so that the magnetic flux direction of the sensor magnet is the same as that of the field magnet 9.

主权项

1. An electric motor comprising:
a rotating shaft formed of a magnetic member; a rotor to rotate in a unified manner with the rotating shaft; a stator that is wound with an armature winding and by its energization, generates a rotating magnetic field; a field magnet that is placed with the stator to magnetize the rotor; a sensor target formed of a magnetic member to rotate in a unified manner with the rotating shaft; a sensor magnet that is placed in a side of the stator to generate a magnetic field passing across the sensor target; and a rotation sensor that is placed in the side of the stator to detect a magnetic flux of the sensor magnet that varies according to a rotational position of the sensor target, wherein a magnetic flux direction of the field magnet is the same as that of the sensor magnet.