RPM-measuring system with a revolving areawide magnetized rotor disposed on a magnetizable support

摘要

An rpm-measuring system with at least one sensor disposed in a motor vehicle on a wheel support arranged at a distance from a component to form a gap between the wheel support and the component, includes at least one magnetized rotor attachable to a motor vehicle wheel or a rotating component, so that the rotor is magnetically shielded from dirt pollution by magnetizable particles or flakes, and a magnetizable support on which the rotor is disposed and which has a back facing the gap between the wheel support or the to cover the gap and to shield the rotor from magnetizable dirt.