Patent ID: 6898994
Filing Date: 2005-05-31
Classification: F16H,Y10T

Abstract:
1. In a ball screw and nut assembly including a ball screw including a tubular portion having an exteriorly helically grooved surface between its opposite ends; a ball nut concentrically encircling said exteriorly helically grooved surface of said ball screw and having a nut interiorly helically grooved surface forming a helical ball raceway with said exteriorly helically grooved surface of said ball screw; and a train of balls within said raceway, an improvement comprising: a. said ball screw tubular portion having an interior surface radially inwardly of said exteriorly helically grooved surface of said ball screw and radially extending axially spaced ball transfer openings through said tubular portion of said ball screw; b. an axially extending cylindrical insert with axially spaced ends and an outer peripheral surface disposed concentrically within said tubular portion of said ball screw, said insert having a pair of end passages and a generally axially extending mid-passage connecting with said end passages, said mid-passage having a non-helical shape formed in said peripheral surface of said insert to provide a ball recirculation pathway radially inward of said ball screw ball transfer openings; said end passages and said mid-passage being formed to retain said balls between said interior surface of said tubular portion and said insert.