METHOD OF MOULDING CERAMIC INSULATOR IN USE FOR SPARK PLUG STRUCTURE

摘要

In a spark plug structure including a metallic shell, a ceramic insulator placed into the shell, and a center electrode placed into the insulator; method of moulding the ceramic insulator comprising steps of; making granular or powdery materials by mixing ceramic powder such as (AlN), (Si3N4) or (A1203) with an organic binder and an auxiliary sintering agent, so that average spherical diameter of the mixed powder falls within 20 - 100 microns; forcing the mixed ceramic into a mould, and pressed in an appropriate configuration; the ceramic thus pressed being sintered under normal pressure at the temperature of 1600 - 2000 degrees centigrade.