| 摘要 |
PROBLEM TO BE SOLVED: To provide a ball screw apparatus, which can easily apply a proper pre-load between a ball screw shaft and a ball screw nut in an assembly process of the ball screw apparatus, and further to provide an electric power steering apparatus having the ball screw apparatus. SOLUTION: The ball screw apparatus 13 of the electric power steering apparatus 10 is composed of the ball screw shaft 12b integrated with a rack shaft 12, first and second ball nuts 23, 24 which are mounted on a motor shaft 36, and are screwed with the ball screw shaft 12b via circulating balls 21 respectively, a fastening nut 48 which is screwed with the motor shaft, and fastens the first and second ball nuts to the end surface of the motor shaft, and a torque applying means 51 which is arranged between the outer periphery of the second ball nut and the inner periphery of the fastening nut, and applies a required relative turning torque between the first and second ball nuts by fastening the fastening nut. COPYRIGHT: (C)2007,JPO&INPIT |
