Patent ID: 6571653
Filing Date: 2003-06-03
Classification: F16H,Y10T

Abstract:
A ball screw comprising a screw shaft formed, on an outer peripheral surface thereof, with a ball rolling groove, a number of balls rolling along said ball rolling groove, a nut screwed with said screw shaft through the balls and seal members disposed at both end portions of the nut, each of said seal members being formed, on an inner peripheral surface thereof, with a spiral projection to be fitted into said ball rolling groove,wherein a lubricant retaining portion, being a slit, is formed on the seal member from an end surface thereof facing inside in the axial direction of the nut to an intermediate portion thereof and said lubricant retaining portion scrapes a lubricant invading into a gap between said seal member and said screw shaft and returns the lubricant to an inner portion of the nut, and wherein a foreign bodies removing portion, being a slit, is formed on the seal member from an end surface thereof facing outside in the axial direction of the nut to an intermediate portion thereof and said foreign bodies removing portion scrapes foreign bodies adhering to an outer peripheral surface of the screw shaft and discharges the foreign bodies outside the nut.