| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a relatively simple and inexpensive one-piece shaft used in common with a york member by forming a first end portion of a tubular material so as to have a non-circular cross section, removing a pair of mutually facing parts of the first end portion and forming a pair of yolk ears in the first end portion. SOLUTION: One part of two materials of mutually facing sides of a first portion 11 of a tube 10 is removed. The part of the material left after removing in such a manner is formed into a U shape, and mutually facing recesses 14 formed in the mutually facing sides of the first portion 11 of the tube 10 are left. Mutually facing yolk ears 15 are formed in such a manner by the residual pair of mutually facing sides. Finally, holes 16 are formed through each yolk ear 15. The square corner of each yolk ear 15 is rounded off. Each hole 16 is coaxially matched and is formed by an optionally suitable means e.g. drilling or punching. The finished yolk shaft may be heat treated in a conventional manner if necessary. |
