Patent ID: 7765846

Claim:
A method of producing a hollow shaft component having a profiling provided for torque transmission at one end thereof, wherein a shaft section between the ends has a smaller diameter than said profiling, said method comprising forming a hollow shaft component having at one end thereof the torque-transmitting profiling and at the other end thereof an external torque-transmitting profile of said a slip joint from a workpiece by: a) cutting a material blank from bar stock, b) subjecting the cut blank to a first cupping wherein a cup-like hollow region with a solid extension is formed by cold extrusion and wherein the cup-like hollow region corresponds at least approximately to the inside diameter and the outside diameter of a profile region intended for forming the profiling, c) subjecting the blank to a second cupping, wherein the hollow region is lengthened from the extension by cold extrusion, d) perforating the bottom of the cup resulting from c) to form a tube, e) cold extruding the tube to commence formation of a hollow shaft section, f) reducing the diameter and wall thickness of the hollow shaft section in a first reduction step and lengthening the hollow shaft section and forming a neck portion that is thicker than the outside hollow shaft diameter adjoining the profile region using cold extrusion, g) starting from said neck portion, further reducing the diameter and lengthening the hollow shaft section in a second reduction step using cold extrusion, h) final pressing the profile region to form the profiling thereon in the form of external teeth by inserting a mandrel with the same diameter into the internal contour in the profile region and forcing an annular die surrounding the mandrel into the end face of the profile region and thereby displacing material into counterteeth of an annular counterprofile die placed around the profile region to form the external teeth of the profiling and an axial projection by cold extrusion, i) forming the external profile of said slip joint, optionally simultaneously with step h), in the section of the hollow shaft opposite the profile region by cold extrusion, and j) removing the projection by turning.