In a recent video, Rollon engineers detail the purpose of preloading linear guides and linear actuators — and when it’s appropriate to employ or avoid preloading.
A wide array of component assemblies for linear motion can be preloaded — including those of track-roller bearings, profile-rail guides, and linear drives such as ballscrews and linear splines. For linear bearings and guides, the clearances between the slider (sometimes called a carriage or less commonly a skate) rolling elements and the linear rail are reduced or eliminated. The result is a more rigid assembly that exhibits no backlash and less deflection when bearing a payload.
Precision motion-control applications involving positioning rely on such preloading to accurately and repeatably situate a payload.