Drive belt pulley

摘要

A drive belt pulley (1) is mounted on a support shaft by a ball race (2) in which the balls are held in a cage ring with uneven spacing of the ball pockets. The ratio of the mean angles subtended by adjacent pockets is (n+2) : (n+1) where n is a whole number, e.g. 6. The cage ring is made of plastics molded with the pockets open to one edge, or is made of rolled metal sheet. The bearing is used for drive pulleys as well as tensioning pulleys.