METHOD OF PRODUCING RACK GUIDE BASE BODY IN RACK-PINION STEERING DEVICE, AND RACK GUIDE

摘要

A method of manufacturing a rack guide base body wherein a cavity (40) is formed which has a pair of semicylindrical convex surfaces (44a and 44b) and a pair of flat surfaces (45) each located between the semicylindrical convex surfaces (44a and 44b), and has a recessed surface (41) located on one axial end portion side inwardly of the semicylindrical convex surfaces (44a and 44b) and the flat surfaces (45) and a cylindrical surface (42) located on the other axial end portion side inwardly of the semicylindrical convex surfaces (44a and 44b) and the flat surfaces (45); a hollow portion (9c) is formed for allowing the cavity (40) to communicate with a hollow portion (10c) at one flat surface (45) and with a hollow portion (8c) at the other flat surface (45); a rack guide base body (50) is die cast by forcing molten metal of aluminum from the hollow portion (10c) into the cavity (40); and runners (56) integrally joined to flat surfaces (55) of the rack guide base body (50) formed by the respective flat surfaces (45) are cut off.