A ball screw device includes a screw shaft having a first thread groove on an outer peripheral surface and a nut having a second thread groove provided on an inner peripheral surface, a notch provided on an end face, and a return hole provided on a bottom surface of the notch orthogonal to an axial direction of the screw shaft and passing through in the axial direction. An end deflector fits into the notch. The nut includes a curved surface portion at a position of a lateral surface of the notch between the second thread groove and the return hole. In a first section, the curved surface portion includes a portion that draws an arc centered at a point positioned outside the second thread groove in a radial direction around a rotation axis of the nut.
Ball screw device and electric power steering device
2021-12-21
Patent
Electronic Resource
English
BALL SCREW DEVICE, ELECTRIC POWER STEERING DEVICE, AND LUBRICANT FOR BALL SCREW DEVICE
European Patent Office | 2023
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