Patent ID: 9088136
Filing Date: 2015-07-21
Classification: F02P,H01T,Y10T

Abstract:
1. A corona igniter for emitting a radio frequency electric field to ionize a fuel-air mixture and provide a corona discharge, comprising: a central electrode formed of an electrically conductive material for receiving a high radio frequency voltage and emitting the radio frequency electric field; an insulator formed of an electrically insulating material surrounding said central electrode and extending longitudinally along a center axis from an insulator upper end to an insulator nose end; said insulator including an insulator outer surface extending from said insulator upper end to said insulator nose end; said insulator outer surface presenting an insulator outer diameter extending across and perpendicular to said center axis; said insulator including an insulator body region and an insulator nose region; said insulator outer surface including a lower ledge extending outwardly away from and transverse to said center axis between said insulator body region and said insulator nose region; said lower ledge presenting an increase in said insulator outer diameter; a conductive component surrounding at least a portion of said insulator body region such that said insulator nose region extends outwardly of said conductive component; said conductive component including a shell surrounding at least a portion of said insulator body region and extending from a shell upper end to a shell firing end; said shell presenting a shell inner surface facing said center axis and extending along said insulator outer surface from said shell upper end to said shell firing end; said conductive component including an intermediate part formed of an electrically conductive material and surrounding a portion of said insulator body region and extending longitudinally from an intermediate upper end to an intermediate firing end; said intermediate part including an intermediate inner surface facing said center axis and extending longitudinally along said insulator surface said from said intermediate upper end to said intermediate firing end; said intermediate inner surface presenting a conductive inner diameter extending across and perpendicular to said center axis; said conductive inner diameter being less than said insulator outer diameter below said lower ledge of said insulator; and said intermediate firing end engaging said lower ledge of said insulator.