A sprocket[1] or sprocket-wheel[2] is a profiled wheel with tooth, or cogs,[3][4] that mesh with a chain, monitor or other perforated or indented material.[5][6] The name 'sprocket' applies generally to any wheel where radial projections engage a chain moving over it. It is distinguished from a equipment in that sprockets are never meshed together directly, and differs from a pulley in that sprockets have tooth and pulleys are clean.

Sprockets are used in bicycles, motorcycles, cars, tracked vehicles, and other machinery either to transmit rotary movement between two shafts where gears are unsuitable or to impart linear movement to a track, tape etc. Maybe the most common form of sprocket may be within the bicycle, in which the pedal shaft bears a huge sprocket-wheel, which drives a chain, which, subsequently, drives a small sprocket on the axle of the trunk wheel. Early automobiles were also largely driven by sprocket and chain system, a practice generally copied from bicycles.

Sprockets sprocket wheelare of various designs, a maximum of efficiency being claimed for every by its originator. Sprockets typically don't have a flange. Some sprockets used with timing belts have flanges to keep the timing belt centered. Sprockets and chains are also used for power transmission from one shaft to another where slippage isn't admissible, sprocket chains becoming used instead of belts or ropes and sprocket-wheels instead of pulleys. They could be operate at high speed and some types of chain are so built as to be noiseless also at high speed.

en_USEnglish