Patent ID: 7632188
Filing Date: 2009-12-15
Classification: F16D,Y10S

Abstract:
1. A universal coupling for interconnecting a first element and a second element rotatable about respective axes that intersect at varying angles, said coupling comprising: a single pair of spherical gears comprising: each of said gears having a respective pitch surface in the form of a respective large theoretical pitch sphere, said large pitch spheres being concentric and having radii which are substantially identical, the pitch circle of each of said gears being a great circle on one of said respective large pitch spheres and said pitch circles effectively intersecting with each other at two pole points separated by 180°; each respective tooth of said gears being formed within one of a plurality of individual smaller theoretical spheres arranged in a circle so that each successive smaller theoretical sphere is tangent to the next smaller theoretical sphere at points of contact falling on the surface of said large pitch spheres, the distance between said points of contact on each smaller sphere defining the normal chordal thickness of each respective tooth; and the axes of said elements intersecting at the center of said large pitch spheres at all times when said gears are rotating in a driving and driven relationship as said axes variably intersect throughout a continuous range from 180° to an angle differing from 180° by a predetermined maximum angle x° so that said elements intersect over a continuous maximum range of 2x°; wherein the surface of each said internal tooth face is tangent to its respective individual smaller sphere at said points of contact shared between said smaller spheres, and wherein the circular shape of the lengthwise curvature of each said internal tooth face is either: