| 摘要 |
PROBLEM TO BE SOLVED: To provide a starting electric motor for an internal combustion engine capable of reducing the number of gear teeth while securing strength of an output shaft and a pinion tooth and realizing reduction of size and weight without spoiling strength. SOLUTION: This pinion is a pinion 7A with gear teeth on its outerperipheral surface and with a bearing 8 fit on its inner peripheral surface, provided on an output shaft 6 of a starting electric motor through the bearing and constituted to start an internal combustion engine as it slides along the output shaft 6 and the gear teeth is engaged with a ring gear of the internal combustion engine. In this case, an inside diameter of a head end part 7a on the side to be engaged with the ring gear is set in the size between an inside diameter and an outside diameter of the bearing. |
