Ball-and-socket joint

A joint between two rods, permitting considerable relative angular movement in any plane. A ball formed on the end of one rod is embraced by a spherical cup on the other. Used in light control systems (e.g., in connecting a pair of bell-cranks which operate in planes at right angles) and in the steering mechanism of motor vehicles, in which both ball and cups are of case- hardened metals. Heavier examples allow a large base plate to be placed under a supporting column in a jack-up pontoon or modified as bridge bearings to allow some articulation. See also ball joint