Abstract: The ball nut of a ball screw at the inner circumference of which a ball groove is provided, wound helically about the longitudinal axis for rolling balls, and at its outer circumference a roller bearing is arranged for rotatably supporting the ball nut, wherein the roller bearing has an inner ring which is supported by means of a support ring arranged on the ball nut in the axial support direction, wherein the support ring is arranged as a result of material deformation in the axial support direction with positive engagement on the ball nut.

Abstract: A roller bearing unit, in particular, a needle bearing unit, which has an outer ring, a roller body cage, roller bodies and several sealing rings. The roller bodies are housed in the roller body cage and are supported externally in the radial direction against the inner surface of the outer ring and are arranged to internally support a shaft aligned in the axial direction. The sealing rings are housed in the outer ring and designed to seal against a fluid flowing the axial direction. The sealing rings are arranged and/or designed such that the resultant sealing effect generated by the rings is direction dependent with relation to the fluids flowing in the axial direction.