Patent ID: 8901467

Claim:
A multi-layer rod shaped ceramic igniter consisting of an elongated tapered electrode having a central core of resistant material and two circular segments with one of said segments on each side of said core and the second of said segments on an opposite side of said core from the first side and two slightly converging facets each having a flat surface extending along said elongated tapered core over the length of said electrode and joined together by said circular segments and coming together to form a tip of said igniter and wherein said two circular segments include a first insulative layer and a second resistive layer disposed on said insulative layer and separated from said core by said insulative layer and wherein said core and said circular segments are made of silicon nitride and molybdenum disilicide and one of said circular segments is connected to a positive potential and the other of said circular segments is connected to a negative potential and in which said core and said resistive circular segments contain essentially identical amounts of silicon nitride and molybdenum disilicide but the particle size in said core is larger than in said circular segments to reduce the resistivity in said core while smaller particles in said circular segments increase the resistivity of said circular segments so that the resistivity of said core is less than the resistivity of said circular segments and wherein said igniter consists of an essentially pore free structure.