| 摘要 |
Provided is a ball screw device for which the wobbling of the end part of the threaded shaft is reduced even when an excessive load is applied to the threaded shaft. Also provided is a method for manufacturing this ball screw device. The method for manufacturing a ball screw device includes an expansion step and an installation step. In the expansion step, a spacer (60) is subjected to heat treatment, said spacer being interposed between an inner ring (21) of a bearing (20) and an axial end surface (13a) of a helical groove formation part (10b) (on the surface of which a helical groove (11) is formed) of a threaded shaft (10), which has the helical groove formation part (10b) and a bearing installation section (10a) supported by the bearing (20). As a result, the inner diameter of the spacer is expanded from a size smaller than the outer diameter of the bearing installation section (10a) to a size greater than the outer diameter of the bearing installation section (10a). In the installation step, the spacer is installed by inserting the threaded shaft (10) through the spacer (60), the diameter of which has been expanded in the expansion step, and then cooling the spacer (60), thereby fitting the inner circumferential surface of the spacer (60) to the outer circumferential surface of the bearing installation section (10a). |
