A method for manufacturing a ball screw according to the present invention includes a seal fixing step of fixing a ring shaped seal to an attachment portion disposed in an end portion of a nut of a ball screw in an axis direction using a fixing member. The attachment portion has an inner circumferential surface having a diameter larger than that of an inner circumferential surface on which a spiral groove of the nut is formed. A through hole is formed in the attachment portion, the through hole penetrating the attachment portion in a radial direction from an outer circumferential surface thereof to the inner circumferential surface thereof. The seal fixing step includes passing the screw through the through hole and engaging the screw with an outer circumferential portion of the ring shaped seal to exert an outward-directed force in the radial direction on the ring shaped seal because of a force of the head pressing the bearing face to fix the ring shaped seal to the nut.

There is provided a ball screw device capable of allowing interference to be easily elastically deformable and decreasing friction resistance of a seal member with respect to a screw shaft without damaging seal properties of the seal member. A predetermined section of a land sliding-contact portion (46) of a sliding-contact portion (40) and a section of a seal piece (37) of a lip portion (31) corresponding to the predetermined section are bent to protrude in one side in the axial direction of a nut (7) so that a protrusion (55) is formed, the bent section of the land sliding-contact portion (46) and the bent section of the seal piece (37) configure a pair of side surface portions (58, 58) of the protrusion (55) and a bottom portion (61) connecting the one side ends of the pair of side surface portions (58, 58).

A ball-screw assembly isolator is provided and includes a housing, a ball-screw, a ball-screw nut, a bearing assembly, a retaining member, a second retaining member, a first compressible member and a second compressible member. The bearing assembly is located between the housing and the ball-screw. The bearing assembly includes an inner race and an outer race. The retaining member is secured by the housing. The second retaining member is secured to the ball-screw nut. The first compressible member positioned between the housing and the outer race. The second compressible member is positioned between the outer race and the retaining member. The retaining member is configured to be preloaded to exert an axial force upon the first compressible member and the second compressible member.

A ball screw (1) having a threaded nut (3) arranged on the threaded shaft (2) and a ball channel (4) wound about the longitudinal axis of the threaded shaft (2), and in which the balls (5) and at least one helical spring (6) are received. This helical spring (6) is supported on a molded part (7) which is inserted into a recess (8) of the threaded nut (3) and closes the recess (8).

There is provided a ball screw device capable of allowing interference to be easily elastically deformable and decreasing friction resistance of a seal member with respect to a screw shaft without damaging seal properties of the seal member. A predetermined section of a land sliding-contact portion (46) of a sliding-contact portion (40) and a section of a seal piece (37) of a lip portion (31) corresponding to the predetermined section are bent to protrude in one side in the axial direction of a nut (7) so that a protrusion (55) is formed, the bent section of the land sliding-contact portion (46) and the bent section of the seal piece (37) configure a pair of side surface portions (58, 58) of the protrusion (55) and a bottom portion (61) connecting the one side ends of the pair of side surface portions (58, 58).