In an automobile, ball joints are spherical bearings that connect the control arms to the steering knuckles. They are used on virtually every automobile made and work similar to the ball and socket design of the human hip joint.
A ball joint consists of a bearing stud and socket enclosed in a casing; all these parts are made of steel. The bearing stud is tapered and threaded, and fits into a tapered hole in the steering knuckle. A protective encasing prevents dirt from getting into the joint assembly. Usually, this is a rubber-like boot that allows movement and expansion of lubricant. Motion control ball joints tend to be retained with an internal spring, which helps to prevent vibration problems in the linkage.
Famous quotes containing the words ball and/or joint:
“The symbolic view of things is a consequence of long absorption in images. Is sign language the real language of Paradise?”
—Hugo Ball (18861927)
“There is no such thing as the Queens English. The property has gone into the hands of a joint stock company and we own the bulk of the shares!”
—Mark Twain [Samuel Langhorne Clemens] (18351910)