Magnetic encoder for detection of incremental and absolute value displacement

摘要

A magnetic encoder for detecting the speed of an actuator adapted to carry out rotational movement or linear movement by a magneto-resistor is disclosed. This magnetic encoder is intended to carry out output conversion by using a stripe-shaped magneto-resistor located close to a magnetic medium with respect to a periodic magnetic field coming out of the magnetic medium on which at least one track of magnetization patterns are recorded by a pitch p in order to generate the periodic magnetic field depending on the required position reading accuracy. When the unit stripe length of the magneto-resistor is represented by l and the closest distance between the magnetic medium and the magneto-resistor is represented by g, the angle alpha defined between the longitudinal direction of the stripe and the surface of the magnetic medium located at the closest part ranges from <IMAGE> to 90 degrees and the lateral direction of the stripe is oriented parallel to the direction of the magnetic field from the magnetization patterns.