- ball bearing
—ball-bearing, adj.Mach.1. a bearing consisting of a number of hard balls running in grooves in the surfaces of two concentric rings, one of which is mounted on a rotating or oscillating shaft or the like.2. any of the balls so used.[1880-85]
* * *One of the two types of rolling, or antifriction, bearings (the other is the roller bearing).Its function is to connect two machine members that move relative to one another so that the frictional resistance to motion is minimal. In many applications, one of the members is a rotating shaft and the other a fixed housing. Each ball bearing has three main parts: two grooved, ringlike races and a number of balls. The balls fill the space between the two races and roll with negligible friction in the grooves. The balls may be loosely restrained and separated by means of a retainer or cage.
* * *one of the two members of the class of rolling, or so-called antifriction, bearings (the other member of the class is the roller bearing). The function of a ball bearing is to connect two machine members that move relative to one another in such a manner that the frictional resistance to motion is minimal. In many applications one of the members is a rotating shaft and the other a fixed housing.There are three main parts in a ball bearing: two grooved, ringlike races, or tracks, and a number of hardened steel balls. The races are of the same width but different diameters; the smaller one, fitting inside the larger one and having a groove on its outside surface, is attached on its inside surface to one of the machine members. The larger race has a groove on its inside surface and is attached on its outside surface to the other machine member. The balls fill the space between the two races and roll with negligible friction in the grooves. The balls are loosely restrained and separated by means of a retainer or cage.The most common ball bearing, with one row of balls, is usually classified as a radial ball bearing (i.e., one designed to carry loads perpendicular to the axis of rotation), but its capacity for carrying an axial, or thrust, load (i.e., a load parallel to the axis of rotation) may exceed its radial capacity. The angular-contact bearing has one side of the outer-race groove cut away to allow the insertion of more balls, which enables the bearing to carry large axial loads in one direction only. Such bearings are usually used in pairs so that high axial loads can be carried in both directions. The clearances in a single-row ball bearing are so small that no appreciable misalignment of a shaft relative to a housing can be accommodated. One type of self-aligning bearing has two rows of balls and a spherical inner surface on the outer race. For pure thrust loads there are ball thrust bearings that consist of two grooved plates with balls between. The outstanding advantage of a ball bearing over a sliding bearing is its low starting friction. At speeds high enough to develop a load-carrying oil film, however, the friction in a sliding bearing may be less than in a ball bearing.
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ball bearing — ► NOUN 1) a bearing in which the parts are separated by a ring of small metal balls which reduce friction. 2) a ball used in such a bearing … English terms dictionary
ball bearing — ball bearings also ball bearing N COUNT Ball bearings are small metal balls placed between the moving parts of a machine to make the parts move smoothly … English dictionary
ball bearing — n. 1. a bearing in which the moving parts revolve or slide on freely rolling metal balls so that friction is reduced 2. any of such metal balls … English World dictionary
ball bearing — n 1.) small metal balls that move in a ring, to make a part inside a machine turn more easily 2.) one of these metal balls … Dictionary of contemporary English
ball bearing — ball ,bearing noun count one of several small hard metal balls that are used between moving parts of a machine to help the parts move smoothly … Usage of the words and phrases in modern English
Ball bearing — For individual balls that are sometimes called ball bearings , see Ball (bearing). Working principle for a ball bearing … Wikipedia
ball bearing — noun bearings containing small metal balls • Syn: ↑needle bearing, ↑roller bearing • Hypernyms: ↑bearing * * * noun, pl ⋯ ings [count] 1 : a part of a machine in which another part (such as a metal pole) turns easily ◇ A ball bearing is made up… … Useful english dictionary
ball bearing — UK / US noun [countable] Word forms ball bearing : singular ball bearing plural ball bearings one of several small hard metal balls that are used between moving parts of a machine to help the parts move smoothly … English dictionary
ball-bearing — see ball bearing … English dictionary
ball-bearing — a term of male abuse Perhaps another way of saying pillock, which is noted under pill1: Terrible as that little ball bearing is, he is less dangerous for us than Herbert Morrison. (Crossman, 1981) … How not to say what you mean: A dictionary of euphemisms