System and method for measuring rotational movement of a component from regions magnetized in a magnetically hard layer of the component

Abstract

A position-sensing system magnetically senses the position of a piston rod moving with respect to a cylinder. A magnetically hard layer on the piston rod provides a recording medium. A track comprised of a plurality of magnetized regions is magnetized in the magnetically hard layer. A plurality of magnetic-field sensors is coupled to the cylinder in proximity of the magnetically hard layer to sense the magnetized track while the piston rod is moving with respect to the cylinder. A first one of the magnetic field sensors is positioned over the track to sense the magnetized regions of the track serially and a second one of the magnetic field sensors is positioned radially to one side of the track. The magnetic field sensors generate signals, in response to sensing the magnetized regions, for use in measuring rotational movement of the piston rod.

Dependencies are inferred from the claim text.