MAGNETIC SENSOR AND MOTOR WITH MOUNTED MAGNETIC SENSOR

摘要

PURPOSE:To provide a magnetic sensor which is used to enhance the position control and the speed control of a motor. CONSTITUTION:The magnetic flux of a magnetic pole on one side of a cylindrical magnetic drum 1 in which N-poles and S-poles are magnetized continuously at equal intervals is detected by a plurality of pole teeth of a first magnetic substance 9, and it is converged by the main magnetic pole of the magnetic substance 9. In addition, the magnetic flux of a magnetic pole on the other side is detected by a plurality of magnetic teeth of a second magnetic substance 10 which is arranged so as to be deviated by the width of the magnetic pole from the first magnetic substance 9, and it is converged by the main magnetic pole of the magnetic substance 10. Then, a change in the magnetic flux between the first magnetic substance 9 and the second magnetic substance 10 is converted into an electric signal by Hall elements 7, and a motor is controlled by using the obtained electric signal whose amplitude difference is small and whose signal accuracy is good.