Patent ID: 6851324
Filing Date: 2005-02-08
Classification: G01L

Abstract:
1. A variable reluctance rotational displacement sensor comprising: an annular sleeve; a coil coaxially aligned within said sleeve; a first ring shaped toothed structure m magnetic communication with said sleeve, coaxially aligned and configured to rotate relative to said sleeve, said first ring including a first plurality of axially directed teeth arranged substantially equidistant about a circumference of said ring on a front portion thereof; a second ring shaped toothed structure in magnetic communication with said first ring and said sleeve, said second ring coaxially aligned and configured to rotate relative to said first ring and said sleeve and including a second plurality of axially directed teeth configured substantially the same as said first plurality of axially directed teeth and oriented adjacent to said first plurality of axially directed teeth on a rear portion of said second ring; wherein said coil generates a signal responsive to a differential rotational displacement between said first ring and said second ring; and wherein said annular sleeve includes an internal flange configured to maintain a selected magnetic air gap with a rear portion of said first ring shaped toothed structure.