Splined
shafts

High-power transmission device consisting of a shaft that is coupled with a hub, and features ridges and grooves along the axial plane. Motion is transmitted by means of the tangential forces exchanged by the lateral surfaces when they come into contact; thus, along the flanks, by hindrance.

The device is suited to transmitting high torques while enabling simultaneous axial movement. For this reason, as well as for its ease of assembly and disassembly and the perfect centering of the hub onto the shaft, it is widely used in industry.

Spline shafts can be as per UNI 8953 standards, with straight parallel flanks, which are employed in speed changes for machine tools, and UNI ISO 4156, with involute flank profiles, employed in the automotive sector.