worm gear reducer

grabcad

A screw engages with and drives a toothed wheel when attached to a shaft with a spiral thread. Worm gears, an old style of gear, date back to ancient times and represent one of the six simple machines. Essentially, a worm gear is a standard spur gear fitted with slightly angled and curved teeth that resemble a screw. This gear modification alters rotational movement by 90 degrees, also shifting the plane of movement due to the worm's position on the wheel. Typically, a steel worm mates with a brass wheel in this design.