Patent ID: 7439733
Filing Date: 2008-10-21
Classification: F15B,G01D

Abstract:
1. A position-sensing system, comprising: a first component; a second component movably coupled to the first component for movement with respect thereto; a magnetically hard layer formed on the second component to provide a recording medium, a plurality of regions of the magnetically hard layer being magnetized to provide an encoding scheme for determining a position of the second component relative to the first component and a second plurality of regions of the magnetically hard layer being magnetized to provide an absolute measurement associated with movement of the second component; and a plurality of magnetic-field sensors coupled to the first component in proximity of the magnetically hard layer to sense the magnetized regions while the second component is moving with respect to the first component, at least two of the magnetic-field sensors being axially positioned to sense the same set of magnetized regions in succession and to generate signals in response to the sensed magnetized regions that can be used to determine a position of the second component.