Patent ID: 6400142
Filing Date: 2002-06-04
Classification: B62D,G01D

Abstract:
A steering wheel position sensor comprising:a mounting member; a steering shaft having a threaded section, said steering shaft being rotatable with respect to a mounting member; a nut threadably engaged with said threaded section, said nut axially moving in response to rotation of said steering shaft, said steering shaft having a predetermined range of rotative positions, wherein said predetermined range of rotative positions correspond to a range of axial positions of said nut; a sliding bar connected to said nut; a magnetic irregularity located at said sliding bar; channel means connected with said mounting member for guiding said sliding bar so as to constrain said sliding bar to move axially as said steering shaft rotates relative to said nut; and galvanomagnetic sensor means connected to said mounting member for providing an electrical signal indicative of the axial position of said nut with in response to axial movement of said sliding bar; said galvanomagnetic sensor means comprising a dual element magnetoresistive sensor comprising: a first magnetoresistor element; a second magnetoresistor element adjacent said first magnetoresistor element; and a biasing magnet stationarily affixed with respect to said first and second magnetoresistor elements, said biasing magnet providing a biasing magnetic field which passes through said first and second magnetoresistor elements, the biasing magnetic field having a range of values at said first and second magnetoresistor elements responsive to the axial movement of said magnetic irregularity.