GB686664A - Improvements in or relating to electroplating apparatus - Google Patents

Abstract

686,664. Electroplating apparatus. WESTINGHOUSE ELECTRIC INTERNATIONAL CO. Nov. 10, 1948 [Dec. 11, 1947], No. 29242/48. Class 41. Electroplating conveyer apparatus comprises a plurality of movable supports for members to be electroplated by immersion in an electrolytic tank, means for moving the supports substantially continuously, and stationary conductor means disposed to be slidably contacted by the supports, the conductor means having alternate cathodic and anodic portions, whereby each movable support is rendered successively cathodic and anodic as it passes over the alternate portions of the conductor means. In the arrangement shown in Figs. 1 and 2, an endless chain driven by sprocket wheels 18, 20 is composed of alternate links 23, 24, the links 24 which are electrically insulated from each other, carrying movable supports 26 for racks 28 holding members 32 to be plated in a tank 10. The supports move in slidable contact with a conductor bar 38 formed with sections 39 electrically insulated from sections 40. The sections 39 are connected to the negative terminal and the sections 40 to the positive terminal of a continuous direct-current source of electric power. The tank 10 is provided with conductor bars 14 for supporting anodes 16. The spacing between the supports 26 is such that at any time a relatively constant number of the supports is in contact with the sections 40, most of the remainder being in contact with the sections 39, also the sections 40 are of lesser length than the sections 39. The members 32 are thus plated for short intervals and deplated for shorter intervals in alternate arrangement. In a modification a stationary anodic conductor bar and a stationary cathodic conductor bar are arranged sideby-side, each being provided on the upper surface with recesses with insulating material therein. The bars are engaged by a pair of spring-pressed contact brackets on each of the supports 26. In the arrangement shown in Fig. 5, a conductor bar 138 supported on the plating tank 130 by insulating brackets 144 is provided with alternate cathodic sections 139 and anodic sections 140 which are adapted to be engaged by loose copper support bars 146 carrying racks for the articles to be plated. The bars are placed in turn on an insulated portion 142 of the bar 130 and are moved across the bar by lugs 136 fixed to an endless belt 134. To enable an increased current density to be applied to the anodic sections of the conductor bar without altering the length of the conveyer an additional source of electric current may be provided and used in conjunction with a rectifier. Another arrangement, which enables the current to the anodic sections to be varied, involves the use of two variable resistances connected respectively in the circuits of the anodic sections and anode plates disposed within the tank. Specifications 630,165 and 642,101 are referred to.