Timing pulley

toothedflat beltmetal

Timing pulleys have teeth or pockets around the outside diameter of the pulley body. Timing teeth engage holes in the metal belt, while timing pockets engage drive lugs on a belt’s inner circumference. As the name implies, these teeth or pockets are used for timing. The power transmission, or driving motion of the belt, is still accomplished via frictional forces between the flat belt and pulley surfaces. Precise, Durable Results with Our Patented Ball Bearing Timing Teeth Type I and II timing pulleys allow cycle repeatability without any pitch accumulation, also known as belt creep, within very precise tolerances. Repeatability is the ability of a single pitch on successive rotations of a belt to return to a home position within a specified tolerance—typically in the range of 0.002” (0.051 mm) to 0.005” (0.127 mm). In a friction drive system, the pulley moves slightly slower than the belt. If not controlled, belt creep in a friction drive metal belt results in a loss of repeatability, affecting the precision of the application. Using Type I or Type II timing pulleys is the best way to maintain system accuracy. Timing elements—particularly timing teeth—must be highly resilient. The material’s hardness and durability is essential to ensure minimal wear from successive engagements of the belt and pulley. Belt Technologies’ patented timing pulley uses hardened ball bearings as teeth, which are specifically designed to provide added resistance to continuous wear and tear.