Sughrue, Mion, Zinn, Macpeak & Seas
Rotational angle sensor having a magnetic member mounted on a rotatable shaft
 A rotational angle sensor includes a cylindrical bobbin, a freely-rotatable shaft provided at the center portion of the bobbin so as to extend in a direction vertical to the central axis of the bobbin, two coils which are wound between the center portion of the bobbin and one side portion thereof and between the center portion of the bobbin and the other side portion thereof, respectively, and a magnetic (or non-magnetic) member which is linked to the shaft so as to be freely rotatable in the bobbin such that a rate at which the magnetic member is deviationally located at one side of the two coils is varied in accordance with a rotational angle, whereby the rotation of the shaft is reflected to the variation of the inductance ratio of the two coils. When the non-magnetic member is used, magnetic fluid is filled in the bobbin. 
Zexel Corporation
G G
G01D G01B
inventional inventional
Hajime
Takahashi