Bishop Innovation Limited

Lyle John McLean

Juergen Dohmann

Johann Friederich Jaeggi

A die apparatus and method for performing a flashless forging operation to manufacture the toothed portion of a steering rack. The die apparatus includes first and second die members and at least one punch member, each having a forming surface shaped substantially as an obverse of a portion of the toothed portion. At least a portion of the forming surface of the first die member is shaped substantially as the obverse of the teeth of the rack. The first and second die members are moveable towards each other to a closed position, thereby partially forging the toothed portion from a blank placed in the die apparatus, and forming a substantially closed cavity defined by the forming surfaces. The punch member is adapted to move into the cavity once the die members are in the closed position, thereby completing the forging operation.

Steering rack manufacture

A die apparatus and method for performing a flashless forging operation to manufacture the toothed portion of a steering rack. The die apparatus includes first and second die members and at least one punch member, each having a forming surface shaped substantially as the obverse of a portion of the toothed portion. At least a portion of the forming surface of the first die member is shaped substantially as the obverse of the teeth of the rack. The first and second die members are moveable towards each other to a closed position, thereby partially forging the toothed portion from a blank placed in the die apparatus, and forming a substantially closed cavity defined by the forming surfaces. The punch member is adapted to move into the cavity once the die members are in the closed position, thereby completing the forging operation.

A method of manufacturing a steering rack bar () by forging, the method comprising the steps of pacing a heated cylindrical rack bar () in a first forging die () and forging a first toothed protion () at one end thereof; removing the rack bar; heating the rack bar at or near the other end of said rack; and placing the other end of the rack bar in a second forging die and forging a second toothed portion () wherein, prior to forging the second toothed portion, the rack bar is axially and angularly aligned to a predetermined axial location and angularly orientated utilising the first toothed portion or features at or near the one end of the rack bar as a datum, and placed and held in the predetermined axial location and angular orientation prior to forging of the second toothed portion.

Growing community of inventors

Maraylya, Australia

Lyle John McLean