Patent ID: 7825573

Claim:
A spark plug assembly for deep well applications, said assembly comprising: an elongated tubular conduit having a top end and a bottom end; an upper ceramic insulator disposed in said conduit adjacent said top end thereof; said upper ceramic insulator having a central bore; a lower ceramic insulator spaced apart from said upper ceramic insulator, said lower ceramic insulator disposed at least partially in said conduit adjacent said bottom end thereof; an outer elastomeric insulator disposed in said conduit between and separating said upper and lower ceramic insulators, said outer elastomeric insulator including a central bore generally aligned with said central bore of said upper ceramic insulator to form a continuous passageway; an elongated electrically conductive central electrode extension disposed in said continuous passageway formed by the aligned said central bores; and an inner elastomeric insulator surrounding at least a portion of said center electrode extension and simultaneously bridging said aligned central bores in said respective upper ceramic and outer elastomeric insulators.