Patent attributes
An end cap in the present linear motion guide unit is made up of an end cap major part and a spacer part, which, once assembled, define a turnaround passage between them to make sure of smooth running of the rolling elements. Especially, the turnaround passage in the end cap when viewed in the sliding direction of the slider is constituted with a curved route whose radius of curvature is constant, which extends from a center (Ok) of a load race to a center (Or) of a return passage, with making a detour to clear an upper edge of a track rail. A carriage of the slider has widthwise opposing return passages lying biased more sidewise inwards or center-ward than load races so as to make an interval or span (Pr) between the return passages less than a sidewise interval or span (Pk) between the load races. The curved route whose radius of curvature is constant, when viewed in the sliding direction of the slider, is arced over a semicircular range of 180 degrees.