GB505981A - Improvements in or relating to electric insulators - Google Patents

Abstract

505,981. Insulators. BULLERS, Ltd., and ROBINSON, W. G. Nov. 16, 1937, No. 31540. [Class 36] An insulator having two metal attachments separated by the dielectric surface of the insulator, at least one of which attachments forms with the insulator a plug-and-socket connection, comprises a metal encircling member embracing the insulator between the attachments and spaced away therefrom, a metal conductor connecting the encircling member with the metal part of the plug-andsocket connection in such manner that the insulating surface or gap between such metal part and the encircling member is open to the atmosphere. In the pin-and-cap type insulator of Fig. 1, the encircling member comprises a ring 17 cemented to a shoulder 16 on the insulator and connected to the pin by a wire 18; alternatively, a ring may be cemented in or a split ring sprung on a groove in the insulator. In the strain type insulator of Fig. 4, a metal ring 27 is cemented to the body 25 and connected to the cap 26. The metal ring may be sufficiently thin to fracture should oxide deposits form between it and the insulator; the ring may be formed by spraying or firing a band of metal on the dielectric surface.