Fabrication and Implementation of a Rotation Sensor Using a Separated Structure Consisting of Magnetic Wire and a Pick-up Coil

Abstract

  A new structure for a rotation sensor using magnetic wires is proposed. The sensor consists of magnetic wires attached directly to a rotating shaft. A pick-up coil and exciting magnets are separately located outside of the rotor. This sensor structure and configuration offers advantages over the conventional structure, whose pick-up coil iswound around a magnetic wire. The location of the pick-up coil and magnets in the proposed method was optimized. It was found that multiple output pulses could be obtained for every turn of the rotating shaft simply by placing corresponding numbers of wires on the shaft. The implementation of this sensor in an electrical vehicle was examined, and an output pulse voltage with an S/N ratio sufficiently high for practical use was observed.