This article is about the type of wheel. For the fictional weapon called a "caster," see Spellgun.

For caster sugar see sugar.

For other uses of castor, see castor.

A caster (or castor) is a type of wheel mounted with an offset steering pivot such that the wheel will automatically swivel to align itself to the direction from which it is pushed. They are commonly found on shopping carts and rolling chairs.

Design

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The key to the function of a caster is a bearing above the wheel assembly that allows the wheel assembly to turn 360 degrees.

See also

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• Caster angle

External links

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• Cast patents.

Mechanical engineering