MANUFACTURING METHOD FOR ELECTROCHEMICAL MACHINING TOOL, HYDRODYNAMIC PRESSURE BEARING MECHANISM, AND ELECTROCHEMICAL MACHINING APPARATUS

摘要

<P>PROBLEM TO BE SOLVED: To manufacture an electrochemical machining tool for forming a dynamic pressure groove at a shaft with high precision and productivity. Ž<P>SOLUTION: The electrochemical machining tool includes the processes of forming a projecting portion for dynamic pressure groove formation on a cylindrical or truncated cone-shaped external surface of an inner member formed from metal; applying an insulation material between the projecting portions; covering surfaces of the projecting portion and the insulation material with a conductive film; forming an outer cylindrical portion on the conductive film by electrocrystallization; and forming an electrode inner surface by removing the inner member so that a cross section of the projecting portion is exposed as an electrode portion while a portion in the vicinity of an inner periphery of the outer cylindrical portion of the projecting portion and the insulation material is being left. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž