| 摘要 |
PURPOSE:To accurately manufacture a sleeve bearing having a dynamic pressure type radial bearing part which is a short and thin tube with a groove. CONSTITUTION:On the internal surface 12 of a blank material 11, a groove is cut by means of a grooving tool 20. A swelling of the internal surface 12 caused by this grooving operation is removed by making a steel ball 35 pass through the internal surface 12 in a ball sizing process. Furthermore, the diameter of the bore of the cylindrical bearing is finished by means of a roller varnishing tool 40, and at the same time, the internal surface 12 is finished so as to be a mirror surface. |
