Can someoone tell me about linear motion bearings?
There are a huge variety of such bearings. Most are more like bushings; that is, just a smooth shaft that fits into a smooth tube, but depending on the sorts of motion, they can be as simple as one flat surface riding on another. By using materials that slide easily on one another, and by facilitating lubrication, they support repetitive linear motion. You find such bearing wherever there is a pounding or hammering motion, but also in devices like elevators and machinery that moves along tracks. Even printers and scanners need something of a long wearing bearing surface to enable the heads to move along the width of the paper. The specifications would be concerned with the diameter and depth of the bearings, but these types of bearings are generally specialized. Yes, most people think about radial bearings – ones that deal with rotation – when they think of bearings: where balls and cylinders often carry the loads. That approach is much less common in linear bearings.
