| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a ball screw for an electric brake actuator, preventing the degradation of a service life while reducing one-sided load resulting from radial load which occurs during braking. <P>SOLUTION: The top type ball screw to be used for the electric brake actuator in an automobile with the rotation of a nut comprises a top member 5 having circulation grooves 9 all arranged in approximate 90°different phases relative to the direction of the radial load R on the nut 3 during braking. The ball screw 1 has a plurality of infinite circuits consisting of screw grooves via which a screw stem 2 is opposed to the nut 3, and the circulation grooves 9 provided in the top member 5 for giving infinite circulation to a ball. The circulation grooves 9 in the plurality of infinite circuits are provided in one top member 5, e.g. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
