Adjustable torque conveyor roller drive

A friction clutch for a conveyor roller bearing apparatus wherein a plurality of small thrust springs are disposed between an adjustable nut and a thrust pad to force a drive sprocket against a back-up friction pad connected to the roller axle shaft. Means such as sleeves around the springs or pins between the nut and thrust pad are provided to minimize or eliminate sideloading on the springs. The faces of the thrust and back-up pads are centrally relieved to concentrate the thrust forces in a band which corresponds with the radial locations of the thrust springs. By this arrangement a very uniform breakaway or release torque characteristic is provided about 360 DEG of relative angular travel between the components.