Patent ID: 6229305
Filing Date: 2001-05-08
Classification: G01D,H02K,H03K

Abstract:
A polar coordinates sensor driven by a poly-phase stator core for generating a polar coordinates signal, the combination comprising:a) a polar coordinates sensor including a high permeability pot core half concentrically inclosing a pick-up coil, the pot core half having the form of an outer cylindrical pole concentrically disposed around a cylindrical central pole leaving an annular pick-up coil space, the central and outer poles joined at one end by an annular base portion, the pick-up coil being wound concentrically around the central pole and having signal leads, the end opposite the base portion forming an annular sensing face portion;b) a toroidal stator having a toroid window, said stator formed of a high permeability material, and wound with poly-phase winding distributions;i) poly-phase excitation being applied to the winding distributions for inducing a rotating driving vector diameter-wise across the toroid window and a fringing hemispherical flux from the stator plane;c) the said polar coordinates sensor being mounted concentrically within the toroid window for coupling the,driving vector to the pot core half, and for coupling a fringing hemispherical flux from the annular sensing face to a workpiece, the driving vector further coupling a magnetic flux coplanar to the pick-up coil turns for an inherent signal null.