Description

Definition. Timing pulleys that are designed with an millimeter-based pitch designation. Timing pulleys mate with same-pitch timing belts in synchronous drives. ... These synchronous belt drive systems are durable, highly efficient, and suitable for many different applications. Timing pulleys are specialized pulleys that have either 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. These teeth or pockets are used only for timing, not for power transmission. Timing belt pitch is the distance in millimeters and/or inches between two adjacent tooth centers as measured on the pitch line of the timing belt. History. The first known timing belt was used in 1945. In the 1950s, Bill Devin built a Panhard racing special with a highly modified engine using Norton Manx cylinders and heads and a toothed rubber belt driving the overhead camshaft on each Norton cylinder head.