Sleeve with interior spline broaching system

A metal sleeve (20) adapted for frictional securement to a softer metal shaft (12), comprising:

• the sleeve (20) having an axis, and having arrays (52, 54, 56) of axially extending interior splines (50), each spline oriented radially inwardly toward the axis;
• a plurality of axially spaced circumferential grooves (30, 32, 34) defining circumferentially extending volumetric spaces between each set of interior splines, each array defining a plurality of frontal cutting edges (60, 62, 64), wherein the sleeve (20) defines an interior spline broaching mechanism for achieving low axial forces to affix the sleeve to a shaft (12), wherein each array (52, 54, 56) of splines (50) has a successively reduced diameter for successively cutting deeper into the shaft (12), as the sleeve (20) is axially inserted onto the shaft (12).

A method of securing a hardened metal sleeve (20) to a relatively softer metal shaft (12), comprising the steps of:

• creating a metal sleeve broaching system (10) to frictionally secure the metal sleeve (20) onto the softer metal shaft (12) by providing a sleeve (20) having an axis, and forming arrays (52, 54, 56) of axially extending splines (50) in the interior of the sleeve (20), with each spline (50) oriented radially inwardly toward the axis;
• forming a plurality of axially spaced circumferential grooves (30, 32, 34) in the interior of the sleeve to create circumferentially extending volumetric spaces between each of the arrays of interior splines to capture chip debris (36, 38, 40) from the metal shaft, wherein each of the arrays defines a plurality of frontal cutting edges (60, 62, 64), wherein each of the arrays (52, 54, 56) of splines (50) has a successively reduced diameter for successively cutting deeper into the shaft (12), as the sleeve (20) is axially inserted onto the shaft (12), whereby the sleeve defines an interior spline broaching mechanism (10) for achieving low axial forces to affix the sleeve (20) to a shaft (12).