Abstract: In a ball screw and nut drive device, a helical ball spindle or channel is formed in the inner surface of a nut body and the outer surface of a screw. Balls are circulated through the helical ball channel being returned from one end to the other of the channel by deflecting channels and a return channel. Each deflecting channel is formed in part by a deflecting member fitted into a recess formed in the inner surface of the nut body. The deflecting member includes a projection for lifting balls out of the helical ball channel into the deflecting channel. The deflecting channel has a rectilinear part which can receive balls from the helical ball channel and a curved part connecting the rectilinear part with the return channel. The deflecting channel in the deflecting member is open along its length and the balls passing therethrough contact a wall in the recess formed in the nut body.