| 摘要 |
<p>Electrical Insulator The invention provides an electrical insulator comprising a cylindrical core of an insulating refractory material, such as porcelain, on to a portion of the curved surface of which a sleeve of insulating polymeric materal is fitted. Metal end-caps , for electrically connecting the insulator, are fitted to the ends of the porcelain core such that there is an exposed portion of the curved surface of the core between the sleeve and each end-cap. Thus, any damaging electrical activity which takes place at the metal end-caps is directed primarily on to the surface of the porcelain core , and not on to the surface of the electrically vulnerable polymeric sleeve , which serves to protect mechanically the relatively brittle porcelain core. Optionally, the polymeric sleeve may have a convoluted or a shedded outer surface to increase the leakage path length of the insulator, or to prevent the formation of a continuous moisture path, or both.</p> |
