火花隙
Spark gap \Spark gap\ (Elec.) The space filled with air or other dielectric between high potential terminals (as of an electrostatic machine, induction coil, or condenser), through which the discharge passes; the air gap of a jump spark.
spark gap n 1: a component of an ignition system; consists of two shaped electrodes and the space between them 2: the gap between two high-potential terminals