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When a worm gear is used, a compact and high speed reduction ratio can be obtained as compared with spur gears. The latter type is also called "throated worm gear". The other is the "drum-shaped worm gear" which is a pair consisting of a drum-shaped worm and a worm wheel. One is a cylindrical worm that meshes with a worm wheel as a pair to form the "cylindrical worm gear". There are roughly two types of worm gears.
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Its history is so old that its existence is described by Archimedes in around 250 BC. The set of a worm and worm wheel is called a worm gear. Even though it is compact it can provide a large speed reduction.Ī worm gear is a thread cut into a round bar, and a worm wheel is a gear that meshes with the worm at a shaft angle of 90 degrees. A worm gear is a type of staggered shaft gear that transmits motion between two shafts that are neither intersecting nor parallel.
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