Worm Gears

Worm gears are used when huge gear reductions are needed. It is common for worm gears to have got reductions of 20:1, and even up to 300:1 or greater.

Many worm gears have a fascinating property that no additional gear set has: the worm can simply turn the gear, but the gear cannot turn the worm. That is because the position on the worm is indeed shallow that when the apparatus attempts to spin it, the friction between the equipment and the worm retains the worm set up.

This feature is useful for machines such as conveyor Rotary Air Compressor systems, where the locking feature can act as a brake for the conveyor when the motor is not turning. One other very interesting usage of worm gears is definitely in the Torsen differential, which can be used on some high-performance cars and trucks.