PLASMA TYPE IGNITION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a plasma type ignition device superior in durability and superior in ignition stability. SOLUTION: The plasma type ignition device 1 performs ignition by making a gas in a discharge space 140 into a plasma state of high temperature and high voltage by impressing a high voltage and supplying a large current from high voltage power sources 20, 30 to a plasma type spark plug 10 which is installed on an internal combustion engine 40 and has a cylindrical insulating member 120 to insulate between a center electrode 110 and a ground electrode 131 and has a discharge space 140 formed in the insulating member 120. The power sources 20, 30 are constituted by making the center electrode 110 as a positive electrode and the ground electrode 130 as a negative electrode. At least at the top end part on the discharge space side of the center electrode 110, a recessed dimple part 111 with the diameterϕD3formed larger than the inner diameterϕD1of the insulating member and the surface opposed to the discharge space 140 of the center electrode 110 recessed to the side of a space countering the discharge space, and having the inner diameterϕD2and the depth G2is formed. COPYRIGHT: (C)2009,JPO&INPIT