Timing Belt Drive

A drive that transmits rotation through a toothed belt meshing with toothed pulleys, without slipping.

A timing belt drive has teeth molded into the inside of the belt, which mesh with toothed pulleys to carry rotation from one shaft to another. A plain flat belt transmits force through friction and can slip; a timing belt meshes tooth-to-tooth, so the speed ratio stays fixed — hence “timing.” It's light, quiet, needs no lubrication, and can provide some gear reduction for free if the two pulleys are different sizes. In robots, it's often used to move a motor away from a joint — for example, mounting it near the body to cut the inertia at the end of a leg or arm — and it also shows up in linear stages and desktop robot arms. The downside is that the belt has some elasticity, so it's less stiff than a gear train, and it stretches loose over time and needs re-tensioning.

ExampleThe X and Y axes of a desktop 3D printer commonly use a GT2 timing belt to move the print head.

Also called

Belt Drive, Toothed Belt Drive

Related

Speed Reducer / Gearbox · Gear Ratio · Linkage Transmission · Tendon-Driven Actuation · Intrinsic vs. Extrinsic Actuation (Proximal Actuator Placement) · Reflected Inertia

Sources

Belt (mechanical) - Wikipedia