Plastic pin insulator has groove at top - for fitting electric cable, and blind hole at base for installing on support, both groove and hole having metal lining or embedment

摘要

Pin insulator, made of a casting resin (which may contain in a filler), has a head portion with a groove, adapted to receive a corded conductor, and a base portion with a vertical blind hole at the bottom for fitting a metal support into it. Both the groove and the blind hole are metal-lined, the metal being identical with that used for conductor and/or support. The respective coeffts. of thermal expansion of casting resin and metal lining should be as nearly the same as paracticable. In a variant, the metal is not superposed upon the resin matrix but embedded in it.