Friction drive
An idler-wheel may be used as part of aIdler pulley
In a belt drive system, idlers are often used to alter the path of the belt, where a direct path would be impractical. Idler pulleys are also often used to press against the ''back'' of a pulley in order to increase the wrap angle (and thus contact area) of a belt against the working pulleys, increasing the force-transfer capacity. Belt drive systems commonly incorporate one movable pulley which is spring- or gravity-loaded to act as aIdler gear
An idler gear is a gear wheel that is inserted between two or more other gear wheels. The purpose of an idler gear can be two-fold. Firstly, the idler gear will change the direction of rotation of the output shaft. Secondly, an idler gear can assist to reduce the size of the input/output gears whilst maintaining the spacing of the shafts.Gear ratio
An idler gear does not affect theApplications
;Reversing An intermediate gear which does not drive a shaft to perform any work is called an idler gear. Sometimes, a single idler gear is used to reverse the direction, in which case it may be referred to as a reverse idler. For instance, the typicalReferences