Method of manufacturing a steering rack
AssigneeBishop Innovation Limited
InventorJuergen Dohmann
Life of this patent
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Abstract
A method of manufacturing a steering rack for a vehicle rack and pinion steering system. The rack comprises gear teeth and a shank that has a constant outside diameter and constant wall thickness over the majority of its length. The method comprises performing a forging operation on a tubular member with an elongate member positioned in the bore of a thickened region of the tubular member. The forging operation forms the gear teeth on the thickened region, and the elongate member is retained within the tubular member. The tubular member is made by performing a forming operation on a length of tube stock such that the outside diameter of the thickened region is smaller than the outside diameter of the shank, and the wall thickness of the thickened region is larger than the wall thickness of the shank.
Claims21
A method of manufacturing a steering rack for a vehicle rack and pinion steering system, said rack comprising gear teeth and a shank, said shank having a constant outside diameter and constant wall thickness over the majority of its length, said method comprising performing a forging operation on a tubular member with an elongate member positioned in the bore of a first region of said tubular member, said forging operation forming said gear teeth on said first region, thereby retaining said elongate member within said tubular member, characterised in that, prior to said forging operation, said tubular member is made by performing at least one forming operation on a length of tube stock such that the outside diameter of said first region is smaller than said constant outside diameter of said shank, and the wall thickness of said first region is larger than said constant wall thickness of said shank, and said tubular member has at least one thickened region adjacent said first region, at least a portion of the outside diameter of said thickened region being substantially the same as said constant outside diameter of said shank, and at least a portion of the bore diameter of said thickened region being substantially the same as the bore diameter of said first region, said elongate member at least partially axially overlapping said thickened region.
Dependencies are inferred from the claim text.