Patent ID: 8753215

Claim:
A spline telescopic shaft comprising: a first shaft and a second shaft that are fitted to each other slidably in an axial direction; a first spline and a second spline that are respectively provided at the first shaft and the second shaft and that engage with each other; and a resin coating that is provided on at least a tooth surface of the first spline and that includes a surface fitted to a tooth surface of the second spline, a clearance being provided between the surface of the resin coating and the tooth surface of the second spline; wherein a groove extending in a direction crossing the axial direction is formed on the surface of the resin coating; wherein at least a part of an abrasion powder composed of resin produced as a result of a heat fitting processing for sliding an intermediate member for manufacturing the first shaft and the second shaft in the axial direction is contained in the groove; wherein the first spline and the second spline extend in the axial direction; and wherein the clearance provided between the surface of the resin coating and the tooth surface of the second spline is a fitting clearance between the corresponding tooth surfaces of the first spline and the second spline, the fitting clearance being 10 μm or less.