| 摘要 |
<p>PROBLEM TO BE SOLVED: To achieve reduction in size and weight while suppressing an increase in manufacturing cost.SOLUTION: A pair of flat surface parts 32, 32 which are parallel with each other are provided on an outer peripheral surface of a base end part of a pinion shaft 10a, and those flat surface parts 32, 32 are connected by projection curved surface parts 33, 33 whose sectional shapes are partial arcs having their centers on the center axis of the pinion shaft 10a. Both the projection curved surface parts 33, 33 are fitted in an engagement hole 20a of a worm wheel 16b so as to align the pinion shaft 10a with the worm wheel 16b. Further, both the flat surface parts 32, 32 are gripped with a tool when a worm reduction gear is assembled or has its performance tested.</p> |
