GB1176839A - Method of and Apparatus for Increasing the Accuracy of Electrochemical Grinding Process. - Google Patents

Abstract

1,176,839. Electrolytic grinding. K. INOUE. April 11, 1967 [April 12, 1966 (2)], No.16479/67. Heading C7B. In electro-chemically grinding a conductive workpiece 10, e.g. of carbon steel or WC containing 6% Co, with a rotating tool electrode, e.g. a contoured graphite grinding wheel 12, electrolyte is applied to a machining surface 15 of the tool electrode, e.g. via nozzle 16, and excess electrolyte is stripped from the surface 15 prior to its juxtaposition with the workpiece, e.g. by squeezing and applying suction at the surface using a porous wiper 18 connected to a suction pump 20 and/or directing an air jet 22 thereagainst from a nozzle 23, to reduce the tendency to irregularly erode the juxtaposed surface. Preferably an organic surfactant such as olive or asphalt oil, stearic or caproic acid or cotyl alcohol may be added to the electrolyte, e.g. aqueous NaNO 2 + KNO 3 solution. For complex e.g. toothed or serrated profiles on the grinding wheel a complementarily profiled squeegee in the form of stiff celluloid, polyethylene or P.T.F.E. foil (130, Fig.6) may be used. Alternatively, a graphite wiper auxiliary electrode (518a, Fig. 9) may span the machining surface of the graphite grinding wheel to mechanically remove excess electrolyte and to electrically transform it. The electrolyte may be recirculated after replenishment. A.C. superimposed on D.C. may be used.