Patent ID: 8414190

Claim:
A track rail configured to be used in a motion guidance apparatus including the track rail and a movable block assembled to the track rail via a plurality of rolling members, the movable block capable of making reciprocating motion relative to the track rail along a longitudinal direction thereof, the track rail comprising: a plurality of rolling member rolling grooves, at least two rolling member rolling grooves on an upper surface of the track rail and at least one rolling member rolling groove on each side surface of the track rail, each of the rolling member rolling grooves extending in the longitudinal direction, wherein when the rolling member rolling grooves are taken along a cross-sectional plane perpendicular to the longitudinal direction of the track rail, and two imaginary lines extending downward in the vertical direction are drawn from ends of the respective grooves located on the outer sides among the at least two rolling member rolling grooves formed on the upper surface, all of the at least one rolling member rolling groove formed on each side surface is positioned in the rail but outside the corresponding one of the two imaginary lines, at least portions of the upper surface and the side surfaces of the track rail, on which the rolling member rolling grooves are formed, the portions being in the vicinity of the respective rolling member rolling grooves, are formed with an inclination angle, the upper surface of the track rail is horizontally disposed and the side surfaces of the track rail are vertically disposed, an imaginary horizontal line is determined to be horizontally passing through the groove curvature centers of the rolling member rolling grooves formed on the upper surface and an imaginary vertical line is determined to be vertically passing through the groove curvature centers of the rolling member rolling grooves formed on each of the side surfaces, the rolling member rolling grooves formed on one side surface, and the rolling member rolling grooves formed on the upper surface and positioned in the vicinity of the rolling member rolling grooves on the one side surface are grouped together into one set, the rolling member rolling grooves formed on the other side surface, and the rolling member rolling grooves formed on the upper surface and positioned in the vicinity of the rolling member rolling grooves on the other side surface are grouped together into another set, and the inclination angle of the portions of the upper surface and the side surfaces is determined by rotating the upper surface and the side surface in the two sets around the intersection of the imaginary horizontal line and the imaginary vertical line determined in the respective two sets.