worm gear

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Last updated

July 15, 2026

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A worm gear is a type of gear system that works in pairs, consisting of a worm (resembling a screw) and a worm wheel (a gear with teeth). This setup is used to transmit motion and torque between shafts that are typically at a right angle (90°) and are nonparallel, nonintersecting.1

Unlike other gear types that require multiple teeth on the pinion for continuous contact, a worm can function with just one thread. This characteristic makes worm gears highly effective for achieving large speed reductions in a single gear pair. If the shafts needed to be parallel, multiple gear pairs would be necessary to achieve a similar ratio.1

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gear
…are usually connected by a worm and gear. The worm resembles a screw, and the gear resembles a quarter section of a long nut that has been bent around a cylinder. The commonest angle between nonparallel shafts, either intersecting or nonintersecting, is a right angle (90°).
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…are usually connected by a worm and gear. The worm resembles a screw, and the gear resembles a quarter section of a long nut that has been bent around a cylinder. The commonest angle between nonparallel shafts, either intersecting or nonintersecting, is a right angle (90°).
Read More