| 摘要 |
PURPOSE:To contrive the stabilization of rigidity of connection and the lightness of weight of a shaft by connecting the shaft in its end part to a yoke through an almost polygonal sectional part and a through hole protrusively forming each top part of a polygon into a circular arc shape. CONSTITUTION:A lower shaft 3 forms its bottom end part by drawing into a polygonal sectional part 11. While a yoke 8 provides a polygon 12, for the polygonal sectional part 11 to penetrate, and a through hole 13, formed by cutting each top part of the polygon into a circular arc shape 12a, to be drilled. And inserting an end part of the lower shaft 3 into the through hole 13, a structure is formed by punching pressing the polygonal sectional part 11 or a focused circular sectional pipe to be spread to a side of the through hole 13. The lower shaft 3 protrudes its end face 14 from the through hole 13 of the yoke 8 to be folded in the peripheral direction of the through hole 13. |
