GB779906A - Improvements in or relating to electro-plating process and apparatus - Google Patents

Abstract

779,906. Electroplating apparatus. ELECTRO-CHEMICAL ENGINEERING CO., Ltd. Sept. 19, 1955 [Sept. 30, 1954], No. 28232/54. Drawings to Specification. Class 41. Articles to be plated are moved in succession through a plating bath and on immersion are subjected to an initial relatively high current density for a relatively short period while articles previously immersed and so treated receive simultaneously a normal plating current density for a relatively long period, the articles during transit through the bath being suspended from a cathode bar which is in two endto-end parts electrically insulated from each other as by an air gap, one part preferably short in length carrying a high current and the other preferably relatively long part carrying a normal plating current. Either a first rectifier is connected between anode and the short part of the cathode bar, a second rectifier is connected between anode and the long part of the cathode bar, and a third rectifier is connected through a switch between the second rectifier and the short part of the cathode bar, the switch being actuated either manually or automatically by vertical movement of the short part of the cathode bar by means of which fresh articles are introduced into the bath; or a pair of rectifiers are connected in parallel between anode and the short part of the cathode bar while a third rectifier is connected between anode and the long part of the cathode bar so that the normal plating current density remains uniform. The articles after plating may be moved on to a further bar by vertical movement of which they are conveyed into a second plating tank.