GB1393138A - Machine for the electrolytic plating of at least one portion of the surface of a conducting piece - Google Patents

Abstract

1393138 Electro-plating apparatus OXY METAL FINISHING (SUISSE) SA 13 June 1972 [16 July 1971] 27604/72 Heading C7B - A conducting workpiece 5, pressed against a support member 4, is electro-plated at portions of its surface defined by openings 12 in the support member. The electro-plating (e.g. with Au) is effected by connecting the workpiece as cathode and pumping electrolyte through nozzles 21 connected as anodes. So as to ensure that the electrolyte simultaneously contacts the total surface area to be plated, pressure within the electrolyte is equalized by pumping the electrolyte into an enclosure 3 through openings which face each other and then through openings 17 and 18 within the enclosure. So as to reduce interaction between (a) streams of electrolyte moving upwardly towards the workpiece from the nozzles 21 and (b) electrolyte moving downwardly away from the workpiece, the openings 12 in the support member 4 have walls arranged slantwise to the nozzle axes. The workpiece is electrically connected by a metallic strip 11 and the nozzles, which are Pt tubes, by a wire 22. As illustrated in Fig. 3 (not shown), the workpiece 5 has openings (6) therethrough. During the electro-plating, the electrolyte is prevented from escaping through these openings by means of a sheet 9 of synthetic rubber interposed between the workpiece and a hydraulic press 8, 10 used for pressing the workpiece against the support member. In a modification, Fig. 4 (not shown), the workpiece is electro-plated over an elongated area, the support member has a correspondingly shaped opening (26) and an electrolyte nozzle (27) has a slit shaped opening. Specification No. 1332568 is referred to.