GB985334A - Improvements in and relating to tool for electrochemical machining - Google Patents

Abstract

A tool for electrochemically machining a workpiece to make a die or punch comprises an electrode, shaped to the required outline and/or contours, secured in spaced relationship to an electrically conductive manifold plate by electrically conductive hollow struts which <PICT:0985334/C6-C7/1> <PICT:0985334/C6-C7/2> <PICT:0985334/C6-C7/3> serve as electrolyte passages. Electrolyte may be supplied or extracted through the struts or may be supplied through some and extracted through others. The electrode may be in the form of a plate 14, Fig. 1, a contoured shell 30, Fig. 4, or a strip 26 bent to the required outline, Fig. 2 (and Fig. 3, not shown). Electrodes of Cu, brass and Al are specified. The outer surface of the struts and any portion of the electrode not to be used for machining may be coated with insulation. As shown in Fig. 1, the tool is advanced by a ram 19 to shape a workpiece 13 having a pre-cut cavity 25, the workpiece 13 resting on a packing piece 23 on a work table 20. Using the electrode shown in Fig. 2, electrolyte flows down struts 27 and over the strip's working edge. As shown in Fig. 4, the struts 31 of the tool have metal 33 cast around them.