US Patent 7579829 Inductive multi-turn encoder

According to one embodiment, there is provided an inductive multi-turn encoder which employs inductive means to determine the number of revolutions a central shaft operably connected to the module has turned. The inductive coils comprise emitter coils and receiver coils, which are operably associated with and opposed to corresponding geared circular disks, which in turn are arranged to implement a predetermined gear reduction ratio. The inductive multi-turn encoder is capable of operating under high temperature conditions and withstanding the effects of various environmental contaminants. The inductive multi-turn encoder disclosed herein is also amenable to miniaturization and low cost manufacturing.