摘要 |
A ball-nut comprising a screw (1) with screw formed threads (2) and in a nut retained balls (11) cooperating with these, the balls running between two ball races (8) suspended perpendicularly to the shaft of the screw (1) and rotatably in the nut. The ball-nut is characterized in that each ball (11) has a radius being so much minor than the radius of the thread profile of the screw (1) and the ball treads (6) of the ball races (8), respectively, that the contact point (15) of the ball (11) with the thread (2) at a load on the ball-nut is situated on a tangent to it declined with an angle alpha being less than 90 degrees and not zero to the shaft (12) of the screw and the contact point (16) of the ball tread (6) of the corresponding ball race (8) situated on a tangent to it declined with an angle beta , which is not zero, but minor or equal to the angle alpha towards the axis (12) of the screw. |