Bearings 183
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The disc is prevented from rotation by a pin inserted through the body and away from
the centre. The bush is also prevented from rotation by a snug, provided at its neck, below the
collar (Fig. 12.9). The space between the shaft and the collar, serves as an oil cup for lubricating
the bearing. The bush and the body are recessed to reduce the amount of machining. The base
of the body is also recessed to serve the same purpose.
Collar thrust bearing
This is generally used for supporting a horizontal shaft under axial load. Further, in this, the
shaft extends through and beyond the bearing. The shaft in a collar thrust bearing may consists
of one or more collars which are either fitted to or integral with the shaft (Fig. 12.10). The
collars rotate against the stationary split bearing surfaces.
(a) (b)
Solid bearing
Split bearing
Collar Oil hole Collars
Fig. 12.10 (a) Single collar bearing, (b) Multi-collar bearing
12.3 ROLLING CONTACT (ANTI-FRICTON) BEARINGS
The bearings, in which a rolling friction is present, are known as rolling contact bearings. As
rolling friction is very much less than sliding friction, rolling contact bearings are called anti-
friction bearings.
The bearing consists of four parts: inner race, outer race, balls or rollers and a cage or
retainer (Fig. 12.11). The inner race is fitted tight into the stationary housing. Figure 12.12
shows the mounting of a shaft with a ball bearing. The arrangement also illustrates the method
used to prevent the axial movement of the bearing.
