GB337096A - Improvements in and relating to electrical insulator bushings - Google Patents

Abstract

337,096. Ferranti, Ltd., and Turner, J. Aug. 12, 1929. Binding-posts and terminals.-A duplex bushing insulator for carrying a conductor through a partition, and more particularly for leading conductors from a casing containing oil-immersed apparatus, comprises an inner insulator carrying a terminal in connection with the conductor and adapted to be secured in airtight manner to the partition traversed. An outer insulator, carrying a terminal for connection by flexible leads to the terminal on the inner insulator, is adapted to enclose that portion of the inner insulator which is external to the partition. In the construction shown, a conductor a, which traverses a partition o, is carried through the centre of a porcelain bushing b and connected to a terminal stem d, clamped against flat surface e, f at the upper end of the bushing. The surfaces of a flange c formed on the bushing b are ground flat and are clamped between a ring g and the partition o. An outer porcelain shell l, which may be formed with rain sheds, is' secured in oiltight manner to the partition o by a clamping ring n and a washer m, the clamped surfaces of the shell being ground flat. A terminal stem p fitted to the upper end of the shell l is connected to the terminal d by leads q. The space between the inner and outer insulators may be filled with oil or compound.