Spark plug cap

摘要

A spark plug cap includes a metal connection member for electrically connecting a spark plug to a high-voltage cord and a tubular rubber body fitted on an end of the high-voltage cord and on an insulating portion of the spark plug to seal the end and the insulating portion. A core member is mounted within the rubber body surrounding the metal connection member, and the core member has a through hole. The through hole places a space, formed between the spark plug and the rubber body, in communication with a contact surface between the core member and the rubber body. Even if the rigidity of the rubber body is increased, this construction eliminates the possibility that the plug cap will be lifted or displaced relative to the spark plug by air compressed within the plug cap when the plug cap is attached to the spark plug.