DYNAMIC PRESSURE BEARING MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a dynamic pressure bearing manufacturing method for forming both thrust and radial dynamic pressure recessed portions into desired shapes while suppressing the deformation of a sintered bearing material due to ultrasonic machining of a thrust face. SOLUTION: To an upper end face 11 on which a spiral groove (the thrust dynamic pressure recessed portion) 12 of the cylindrical sintered bearing material 1A conditioned with a density of 6.6-7.4 Mg/m3, ultrasonic machining is applied so that the upper end face 11 has more density. The spiral groove 12 is formed on the upper end face 11, followed by a separate groove 15 and a circular face (the radial dynamic pressure recessed portion) 16 formed on an inner peripheral face 14 of the sintered beating material 1A. COPYRIGHT: (C)2006,JPO&NCIPI