| 摘要 |
PROBLEM TO BE SOLVED: To improve the durability and reliability, and to reduce the number of part items by sealing inside of a motor case with a support member for supporting an output shaft of an electric motor. SOLUTION: A motor case 22 of an electric motor 21 is fitted to a motor fitting part 3 of a housing 1, and an output shaft 25 is turnably supported by a seal bearing 28 and a ball bearing 26. The seal bearing 28 is fixed to the inside of a bearing housing part 3E of the motor fitting part 3 by a partitioning plate 30 while preventing a fall thereof. A worm 19 is engaged with a worm wheel 20 provided in a steering shaft. With this structure, the seal bearing 28 and the partitioning plate 30 receive the reaction force in the axial direction applied to the output shaft 25 from the worm wheel 20, and inside of the motor case 2 can be sealed in relation to the lubricating oil of the worm wheel 20. The output shaft 25 support structure also works as the motor case 22 seal structure so as to reduce the number of parts items. |
