Patent ID: 8869582

Claim:
A die apparatus for forging a steering rack from a bar, the steering rack comprising a toothed portion, the toothed portion comprising an array of gear teeth, the die apparatus comprising a first and a second assembly, the first and second assemblies being movable towards each other along an axis by means of a press to forge the steering rack, the first assembly comprising a tooth die supported by a first bolster, the tooth die having a toothed forming surface shaped as the obverse of the gear teeth, the second assembly comprising a second bolster, first and second side dies, and a centre punch, the centre punch being disposed between the first and second side dies and opposite the toothed die, characterised in that the second assembly further comprises a third bolster and a bias means, the third bolster being disposed between the first and second bolsters and being movable relative to the second bolster along the axis, the bias means being adapted to bias the third bolster towards the first assembly, the first and second side dies being supported by the third bolster, and the centre punch being supported by the second bolster, the arrangement being such that as the die apparatus closes, the third bolster abuts the first assembly to form a closed forging cavity and then, as the die apparatus continues to close, the centre punch penetrates the closed forging cavity to complete the forging of the steering rack.