Motor Bearings – Functions and Types

The bearings can be one of the two types, a plain bearing (sliding contact) or an anti-friction bearing (rolling bearing), depending on the design parameters of the machine element, each of the two types of bearings, plain and anti-friction, is available for design with linear motion, radial loads and axial loads.

Bearings may be classified into three general classes
Guide or flat bearings, which support linear motion in machine tables and slides.

Thrust bearings, which support rotational motion in machine elements that have axial loads i.e., the load is applied along the central axis of the rotating shaft

Radial bearings, which support rotational motion in shafts with radial loads i.e., the load is applied along the radius of the rotating shaft.

Anti Friction or Roller Element bearings

Anti – friction bearings or roller – element bearings, as they are often called, use a rolling element (ball or roller) between the loaded surfaces.
Anti-friction bearings are divided into two categories,
a) ball bearings
b) Roller bearings.

Ball bearings have five general types:
Guide, Radial, Thrust, Self – aligning and Angular contact.

Roller bearings have four general types: Cylindrical, Thrust, Spherical and Taper.

Roller and Ball bearing types
Guide bearing: The ball guide bearing is used for linear motion where very low co-efficient of friction and extreme smoothness in operation are desired.
Radial bearing: The first radial bearing is the single – row, deep – groove ball bearing, most widely used anti – friction bearing. Second radial bearing is the cylindrical roller bearing is capable of carrying larger radial loads at moderate speeds than those carries by radial ball bearings using the same size bearing.
Thrust bearing: First the ball thrust bearing is designed for axial (thrust) loads only – no radial loads. Second spherical roller thrust bearing is capable of very heavy axial loads as well as moderate radial loads.
Angular contact ball bearing: The shoulders in this provides for thrust (in one direction only) that is larger than the single row, deep radial ball bearing can handle.
Taper roller bearing: A pair of taper roller bearing is capable of handling both very large axial and radial loads.