Patent ID: 7116098

Claim:
A limit and position sensing system, comprising: a sensor assembly including (i) a first electrical conductor arranged in a first plane and having first and second ends, said first electrical conductor coiled outwardly in a clockwise fashion starting at said first end to form a first coil region, said first electrical conductor coiled outwardly in a clockwise fashion starting at said second end to form a second coil region with uniform spacing being defined between rings of said first coil region and said second coil region along an axis of said first plane, (ii) a second electrical conductor arranged in a second plane parallel to said first plane, said second electrical conductor forming a single coil with rings thereof being uniformly-spaced and with portions of said rings of said single coil that lie between said first end and said second end of said first electrical conductor being parallel to said axis, and (iii) ferromagnetic material arranged in a third plane parallel to said first plane and said second plane, said ferromagnetic material aligned with said first coil region, said second coil region and said single coil such that said ferromagnetic material spans beyond (a) said first end and said second end of said first electrical conductor, and (b) said portions of said rings of said single coil; and an emitter spaced apart from said sensor assembly for transmitting a periodic electromagnetic wave towards said sensor assembly to be incident on said first electrical conductor and said second electrical conductor prior to being incident on said ferromagnetic material.