Patent ID: 6547437
Filing Date: 2003-04-15
Classification: F16C

Abstract:
A curvilinear motion guide unit comprising a track rail extending curved with a preselected curvature and having lengthwise side surfaces made thereon with first raceway grooves, and a slider fitting astride over the track rail for movement in a sliding manner along the track rail;wherein the slider is comprised of a casing provided with second raceway grooves extending curved in conformity with the first raceway grooves and return passages formed corresponding to the second raceway grooves, end caps mounted on forward and aft and faces of the casing, each to each end face, and provided therein with turnarounds connecting the second raceway grooves to the return passages composed of curved raceways defined between the first and second raceway grooves, the turnabouts and the return passages, and end seals attached on the end caps, each to each cap; wherein the forward and aft end faces of the casing are each arranged such that an imaginary plane including any one of the end faces and normal to a top surface of the track rail coincides with a radial plane extending through the center of curvature of the track rail, and the return passages are opened on the forward and aft end faces at locations that are closer to a centroidal axis of the track rail than locations where the raceways are made open of the forward and aft end faces, and wherein the slider fits astride over radially outside and inside rims of the track rail to conform the track rail, and the return passages are made opened on the forward and aft end faces at locations that are above the outside and inside rims of the track rail and closer to the centroidal axis of the track rail than the outside and inside rims of the track rail.