Ball bearings for longitudinal and turning movements,comprising guides or circuits of balls in closed circuits

Claim 1

An improvement in a ball bearing mounted between an external ring and an internal shaft wherein the ring and shaft are adapted for relative unlimited longitudinal and/or rotational movement, the ball bearing comprising a freely rotatable ball cage interposed between the ring and shaft and with said ball cage defining closed circuits ball races in which balls circulate and rotate upon relative movement between the ring and shaft, said ball races each comprising two rectilinear parallel portions in side-by-side relationship, said portions being open ended and extending into closed arcuate end portions so as to define said closed circuits, the inner periphery of said ring having raised portions to ensure load-carrying contact with the balls within the open portions of the cage, and recessed portions for the unloaded return movement of said balls, wherein said improvement comprises in that said open-ended ball race portions are inclined relative to the axial generatrices of said cage such that said portions have a helicoidal formation and impart to the balls, during relative rectilinear movement of said ring and shaft, a direction of rectilinear motion parallel to one another but angularly offset, causing the cage to constantly rotate relative to said ring or shaft, the rotation of sAid cage being in response to the directional change of movement of the balls upon entering the opened portions of said ball races and contacting the raised portions of the inner periphery of said ring, and said raised portions forming the load-bearing surfaces whereby, during the relative rotational movement of said ring or of said shaft, the angularly offset balls successively contact the raised portions of the miner periphery of said ring.