Marshall Air 144321

GEAR IDLER 28 TOOTH 20DP

A gear or cogwheel is a rotating machine part having cut teeth or, in the case of a cogwheel, inserted teeth (called cogs), which mesh with another toothed part to transmit torque. Geared devices can change the speed, torque, and direction of a power source. Gears almost always produce a change in torque, creating a mechanical advantage, through their gear ratio, and thus may be considered a simple machine. The teeth on the two meshing gears all have the same shape. Two or more meshing gears, working in a sequence, are called a gear train or a transmission. A gear can mesh with a linear toothed part, called a rack, producing translation instead of rotation.

An idler or idler-wheel is wheel or pulley which serves only to transmit rotation from one shaft to another (or as a to guide or tension a belt), in applications where it is undesirable to connect them directly.