Patent ID: 6310473
Filing Date: 2001-10-30
Classification: G01D

Abstract:
A magnetic rotational position sensor for sensing each degree of rotation of a control shaft about a first rotational axis over a definable range of rotation, said magnetic rotational position sensor comprising:a loop pole piece including a plurality of pole pieces serially adjoined in a closed configuration to define an air gap area, a first pole piece of said plurality of pole pieces having an inner surface swept out over the definable range of rotation by an outer end of a first radius having its opposite end located on a second rotational axis, a second pole piece of said plurality of pole pieces having an inner surface swept out over the definable range of rotation by an outer end of a second radius having its opposite end located on said second rotational axis;a magnet having a first pole surface and a second pole surface to generate magnetic flux, said magnet disposed within said air gap area of said loop pole piece,wherein said first pole surface of said magnet faces said inner surface of said first pole piece and said second pole surface of said magnet faces said inner surface of said second pole piece to enclose said magnetic flux within said loop pole piece whereby a magnetic field is established throughout said air gap area,wherein said first pole surface of said magnet spatially faces said inner surface of said first pole piece to define a working air gap area of said air gap area therebetween, andwherein said loop pole piece and said magnet are adjoined to the control shaft to synchronously rotate about said second rotational axis for each degree of rotation of the control shaft about the first rotational axis over the definable range of rotation whereby each degree of rotation of the control shaft about the first rotational axis over the definable range of rotation exclusively corresponds to a distinct degree of synchronized rotation of said magnetic field about said second rotational axis over the definable range of rotation; anda magnetic flux sensitive transducer disposed within said working air gap area, said magnetic flux sensitive transducer being operable to sense a magnetic flux density of any portion of said magnetic flux passing through said magnetic flux sensitive transducer, wherein said inner surface of said first pole piece and said first pole surface of said magnet are contoured to arcuately configure said working air gap area therebetween whereby said magnetic flux sensitive transducer is operable to sense a different magnitude of magnetic flux density for each degree of said synchronized rotation of the control shaft and said magnetic field over the definable range of rotation.