Electrolytic machining method and electrochemical machining device hydrodynamic grooves in the dynamic pressure bearing

摘要

PROBLEM TO BE SOLVED: To perform electrochemical machining high accurately in an arbitrary groove depth in accordance with a groove position, while attaining reduction of a cost and improvement of productivity, even in a dynamic pressure groove of complicated and fine shape. SOLUTION: Based on a characteristic in which a machining speed in the groove depth direction in a workpiece 142 by electrochemical machining is in inverse proportion to a machining clearance 150 between an electrode exposed part 143a and the workpiece 142, the machining clearance 150, corresponding to a groove depth of a worked dynamic pressure groove 142a, is narrowed relating to a location deepening the groove depth, and widened relating to a location shallowing the groove depth, electrochemical machining is performed, so as to deepen the groove depth in a location of the narrow machining clearance 150 and shallow the groove depth in a location of the wide machining clearance 150, in accordance with a groove position, so that electrochemical machining of arbitrary groove depth can be performed.