GB1144739A - Electrosharpening process - Google Patents

Abstract

1,144,739. Electro-sharpening. GILLETTE CO. Jan. 15, 1968 [Jan.17, 1967], No.2175/68. Heading C7B. A process of electro-sharpening, e. g. of razor blades, tools, knives, needles or electrical contacts, comprises making the object to be sharpened the anode in an electrolytic bath and positioning in said bath an electro-positive control electrode relative to the area of the object being sharpened so as to influence and control the current density in said area. The control electrode is preferably as electro-positive as the object to be sharpened, or more electro-positive than said object, e.g. by using a circuit in which connections from the positive pole of the source of current to the anode to be sharpened and the control electrode are separated by a variable resistor (8), Fig. 1 (not shown). The control electrode may be positioned parallel to the apex of the blade edge, e.g. at a distance of 0À01 - 0À05 inch therefrom, or elsewhere with relation to the blade to produce a desired shape of cutting edge. A holder for supporting a razor blade during said treatment is shown in which the blade is connected to the source of current by conductor 34 and the counter electrode 16 is positioned parallel to the blade edge supported between members 36, one of which serves to connect said electrode to the electric supply. For sharpening of points, e.g. needles or electrical contacts, the control electrode may comprise a small bared portion of a wire covered by a thick insulating portion. The control electrode may be of stainless steel or of platinum, and for sharpening a razor blade a circular stainless steel disc may be used.