Bearings are, by definition, parts of a machine that bear friction between a rotating part and its housing. Ball bearings are the most common type of bearing, and as their name implies, use bearings to maintain the separation between the inner races. Ball bearings are most often used between cantilever and rotary shafts to transfer axial or radial load and need to be retained in all three directions (radial, axial, and circumferential) in relation to their housings and shafts. In this blog, we’ll use some examples of bearings in machinery, and their retaining methods to explain how they work.
In an idler pulley, which regulates the idler in an automobile engine, the pulley is mounted with a cantilever pin, while a bearing retaining collar is used to fix the idler pulley bearing. A washer between the bearing types and the collar provides access to the collar’s tightening screw. The washer’s outer diameter needs to match the outer diameter of the bearing’s access ring.
Multiple retaining methods can be used in conjunction with one another. Bearings mounted on two t-shaped bearing holders have three retaining methods placed upon them. First, a metal washer is used on the tightening side of the cantilever pin, holding it against the inner ring of a radial bearing. Secondly, a bearing spacer is placed between the link arm and a bearing to support the link’s rotation motion. Finally, a bearing on the opposite end is fixed to the cantilever pin shaft by its inner ring with a ball bearing end cap.
Rotating shafts are retained by bearing holder sets and bearing nuts by anti-loosening set screws or bearing lock nuts. Loosening the bearing nut is prevented by using a set screw and a set piece made of copper. The copper set piece is first inserted into a screw hole, and the screw is tightened to crush the soft copper alloy on the soft thread to prevent the bearing nut from loosening. Bearing holding pins, also called bearing shaft screws, can also be used. A bearing pin holds against the inner ring’s outer diameter from the end side, and a collar from the inside is pressed against the inner ring’s outer diameter to fix the bearing to the shaft.