| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power steering device in which grease in a worm wheel can be prevented from mixing into grease of a gear in a sensor case.SOLUTION: An electric power steering device 100 includes a worm wheel 26 which is fitted to a pinion shaft 22 and to which a steering force is input by an electric motor 21 and a rotation angle detection part 32 which detects a rotation angle of the pinion shaft 22. The rotation angle detection part 32 includes a center gear 41 which is fitted to the pinion shaft 22 and has a gear part 41a on an outer circumference, outer gears 42, 43 which mesh with the gear part 41a, a calculation part 44 which calculates a rotation angle of the pinion shaft 22 based on rotation of the outer gears 42, 43 and a sensor case 46 which has a housing part 46b for housing a center gear 41 and outer gears 42, 43 and has a through-hole 47 allowing the penetration of the pinion shaft 22 therethrough. A groove 50 is formed on an inner surface of the housing part 46b of the sensor case 46 and on the circumference of the through-hole 47. |
