Sensor for measuring relative movement between a vehicle and a track by sensing magnetic field distortions

An apparatus for measuring a relative movement between a magnetically levitated vehicle and a track on which said vehicle can travel, by sensing distortions in a magnetic field to produce measured values representing said relative movement comprising a rail (4) of magnetically conducting material with uniformly spaced teeth in said rail forming part of said track, magnetic sensor means carried by said vehicle, said sensor means comprising magnetic transmitter means including at least one alternating current energized transmitter coil for generating a magnetic field having normally undisturbed field line extending in a given direction, magnetic receiver means including at least one receiver coil for sensing said distortions, said magnetic receiver coil and said magnetic transmitter coil each having a respective preferred coil axis, said magnetic receiver coil being located in such a position in said generated magnetic field that said preferred axis of said magnetic receiver coil extends approximately perpendicularly to said undisturbed field lines, said coil axes being spaced from each other by a predetermined spacing, said coil axes being located in a common plane parallel to said rail for measuring said relative movement.