Patent ID: 7735612

Claim:
A brake adapted to be rotationally coupled with an output shaft, the brake comprising a housing including a first surface having a plurality of depressions circumferentially spaced about an axis, a rotatable actuator having a second surface, said second surface having a plurality of depressions circumferentially spaced about said axis, said first surface depression and said second surface depression being adjacent to and facing each other, and a ball positioned between each said first depression and each said second depression, a disc assembly including a plurality of stationary discs and a plurality of rotatable discs positioned between said stationary discs and carried by the output shaft, a bearing interposed between and in contact with said rotatable actuator and one of said stationary discs of said disc assembly, stationary discs of said disc assembly, a lip extending from said rotatable actuator, said lip including a tapered surface, said bearing is an annular roller bearing positioned between and in contact with said rotatable actuator and one of said stationary discs, said lip radially locating said annular roller bearing on said rotatable actuator, and biasing means centered about and biasing means centered about said axis and adapted to bias said rotatable actuator toward said housing, such that when said rotatable actuator rotates, said rotatable actuator moves axially away from said housing, causing a braking force to be applied to the output shaft.