Patent ID: 7533593

Claim:
A ball screw unit with dust cleaning and ball deflecting element fixing mechanism having a nut proper sleeved on a screw bolt with rolling balls rolling therebetween to cause a relative motion of the nut proper and the screw bolt, comprising; the nut proper having a spiral rolling slot in an inner surface thereof to couple with the screw bolt thereby allowing the rolling balls to roll therebetween; a circulation tunnel formed at an end of the spiral rolling slot of the nut proper; a ball deflecting element fixed to the circulation tunnel; an annular inlaid slot formed in the nut proper and outside of the ball deflecting element; and a fixed dust scraper formed into an annular shape and fixed into the annular inlaid slot, the annular dust scraper being made of an annular C shaped packing covered with a resilient covering layer over an outer fringe thereof, wherein a width between two sides of the covering layer is broader than that of the annular inlaid slot so that the scraper is able to forcibly press and fix the ball deflecting element at sides thereof, and an inner fringe of the covering layer is formed into a continuous spiral scrapping tip facing against the rolling spiral slot of the screw bolt, and a side fringe of the spiral scrapping tip is formed into an arcuate scrapping edge facing against a spiral wall and a crest of thread of the screw bolt, wherein at least one stop pillar is provided between the nut proper and the ball deflecting element for fixing the scraper at position, and wherein the stop pillar is provided on a wall surface of the annular inlaid slot of the nut proper abutting on the ball deflecting element, and a corresponding detention hole is formed on the scraper so as to fix the scraper at position on the nut proper by trammeling the stop pillar in the detention hole.