Patent ID: 6016055
Filing Date: 2000-01-18
Classification: G01P,H02K

Abstract:
A device for measuring the rotation speed or detecting the direction of rotation of a rotary magnetic field, comprising:a rotating rotor spindle;a magnet wheel secured on said rotor spindle, said magnet wheel having a permanent magnet with magnet poles for generating a rotary magnetic field, said poles disposed in a radial plane perpendicular to said rotor spindle;a printed circuit board disposed approximately perpendicular to said rotor spindle for receiving an electronic circuit;a Hall sensor secured as an integrated component on said printed circuit board, said Hall sensor having a sensor surface extended parallel to said printed circuit board; anda magnetic flux guide element of high permeability disposed in the vicinity of said magnet wheel and substantially perpendicular to said sensor surface of said Hall sensor, for deflecting the magnetic field of said magnet wheel in an axial direction to increase magnetic flux density in the vicinity of said Hall sensor, said magnetic flux guide element extending in an axial direction along an imaginary longitudinal axis and disposed so that the axis passes through said surface of said Hall sensor.