| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric power steering device capable of reducing the width of feed bearings of a movement conversion mechanism in contrast with the size of rolling elements. SOLUTION: This electric power steering device has a steering shaft 1 formed with a screw thread 10 on its outer peripheral, a rotating tube 2 supported at the outside of the steering shaft 1 concentrically rotatably, and multiple feed bearings R<SB>1</SB>-R<SB>4</SB>, of which outer ring is engaged with and held by holding parts 2b, 2c, 2d, and 2h formed eccentrically inside the rotating tube 2, of which inner ring is engaged with the screw thread 10 at one location of its inner peripheral, and in which multiple rolling elements roll between the outer ring and the inner ring filled with lubricant. The electric power steering device assists steering by converting rotation of the rotating tube 2 by a steering assist motor (not shown in the figure) into movement in the longitude direction of the steering shaft 1 by rolling of the feed bearings R<SB>1</SB>-R<SB>4</SB>guiding the screw thread 10. The feed bearings R<SB>1</SB>-R<SB>4</SB>have a holder to hold the rolling elements, and the holder is constituted to seal lubricant. COPYRIGHT: (C)2003,JPO |
