Patent ID: 8542007
Filing Date: 2013-09-24
Classification: G01D

Abstract:
1. An inductive position sensor, particularly a rotational-angle sensor, for determining the position of a movable element, said sensor comprising: two first transmitter units for generating two site-dependent first alternating fields having an identical first frequency, said first alternating fields being phase-shifted relative to each other by substantially 90°, two second transmitter units for generating two site-dependent second alternating fields having an identical second frequency differing from said first frequency, said second alternating fields being phase-shifted relative to each other by substantially 90°, a first and a second oscillating circuit arranged on or in an element which is movable within the total alternating field generated by said first and second oscillating circuits and the position of which is to be determined, said first oscillating circuit configured to be energized by the first total alternating field generated by said first transmitter units and to generate a first oscillating-circuit alternating field having said first frequency, and said second oscillating circuit configured to be energized by the second total alternating field generated by said second transmitter units and to generate a second oscillating-circuit alternating field having said second frequency, a first receiver unit receiving said first oscillating-circuit alternating field, a second receiver unit receiving said second oscillating-circuit alternating field, a first evaluating unit for determining the phase shift between said first oscillating-circuit alternating field and at least one of said two first alternating fields, and a second evaluating unit for determining the phase shift between said second oscillating-circuit alternating field and at least one of said two second alternating fields, said two first transmitter units, said first oscillating circuit, said first receiver unit and said first evaluating unit forming a first subsystem, and said two second transmitter units, said second oscillating circuit, said second receiver unit and said second evaluating unit forming a second subsystem, wherein said subsystems, without being galvanically connected to each other, are coupled to each other in such a manner that one said subsystem is configured to detect when no alternating fields are generated anymore in another subsystem or in the other subsystems and said first transmitter units and said second transmitter units are alternately controllable to alternately generate said first and second alternating fields based on detecting when no alternating fields are generated.