| 摘要 |
A method for forming a one-piece steering shaft member, such as an externally splined male steering shaft member (or yoke shaft) or an internally splined female steering shaft member (or slip yoke) is disclosed. A hollow cylindrical tube is initially provided which is preferably formed from a blank of a metallic material, such as aluminum, having an elongation factor of at least fifteen percent. It is desirable that the tube have a uniform wall thickness and define an outer diameter which is substantially uniform along the length thereof. The outer diameter of one end of the tube is reduced from its original diameter. A splined surface is formed in the reduced diameter end portion of the tube. The splined surface is formed on the external surface of the yoke shaft and on the internal surface of the slip yoke. The other end of the tube is then deformed so as to provide a generally hollow rectangular cross sectional shape. This can be done in such a manner as to provide uniform wall thicknesses for all four of the sides of the hollow rectangular end of the tube. Alternatively, a first pair of opposed sides of the hollow rectangular end of the tube may be formed having a first wall thickness, while a second pair of opposed sides may be formed having a second wall thickness different from the first wall thickness. U-shaped portions of material are next removed from two of the opposed sides of the hollow rectangular end of the tube. Lastly, a bore is formed through each of the yoke ears, and the square corners of the yoke ears are rounded off. The finished steering shaft member may be heat treated in a conventional manner if necessary. |
