Improvements in and relating to junction boxes for electric cables as used chiefly in collieries

摘要

171,250. Greengate & Irwell Rubber Co., Ltd., and Povey, R. Sept. 15, 1920. Junction boxes; binding-posts and terminals ; continuity couplings.-Junction boxes are built up of a number of interchangeable) units to the size or arrangement required. Each unit consists of a rectangular box b having removable covers r to the top and two or three sides, and a cable entrance c in the remaining side. A row of terminal. pillars j' is inserted diagonally in each unit, and standard links o are used to couple corresponding terminals together. The units are bolted together by the bolts of the covers which have been removed. When the junction is completed the whole is filled with bitumen to seal the cables and fix the terminals in place. The cable entrance c is a tubular extension into which a conical metal bush d comprising a packing gland is inserted. The inner armouring e2 is laid upon this, and a conical washer g of wedge section is laid over the former, followed by the outer armouring e1. A clamping plate h is forced upon the whole to complete the joint. The continuity of the coupling is ensured by a lug on the conical washer, which is connected by a wire to similar lugs on the remaining units of the junction. The terminals, Fig. 3, are each mounted upon porcelain blocks k fixed by screws to a metal plate m. They comprise a clamp n for one core of the cable, which consists of a screw eye, through which the core is threaded, having projecting wings n1 so that it may be drawn into close contact with a shaped surface on the side of the terminal pillar.