Patent ID: 8786392
Filing Date: 2014-07-22
Classification: F02P,H01F,Y10T

Abstract:
1. An igniter for igniting a fuel-air mixture in a combustion chamber, comprising: a coil extending longitudinally along a coil center axis for receiving energy at a first voltage and for transmitting the energy at a second voltage higher than the first voltage, said coil including a plurality of windings each extending circumferentially around said coil center axis, each of said windings presenting a winding gap spacing said winding from an adjacent one of said adjacent windings, a magnetic core disposed along said coil center axis between said windings, said magnetic core including a plurality of discrete sections, each of said discrete sections being spaced axially from an adjacent one of said discrete sections by a core gap, wherein said coil extends longitudinally from a coil low voltage end for receiving the energy at the first voltage to a high voltage end, said coil presents a coil length between said coil low voltage end and said coil high voltage end, said magnetic core extends from a core low voltage end adjacent said coil low voltage end to a core high voltage end adjacent said coil high voltage end, said discrete sections of said magnetic core together present a core length extending from said core low voltage end to said core high voltage end, and said core length is greater than said coil length, a coil former made of an electrically insulating non-magnetic material and presenting a former thickness spacing said windings from said magnetic core, wherein said coil length and said core length present a length difference therebetween and said length difference is equal to or greater than said former thickness, a coil filler formed of an electrically insulating material different from said coil former disposed in said winding gaps and spacing each of said windings from the adjacent one of said windings, and said coil filler having a dielectric strength of at least 3 kV/mm, a thermal conductivity of at least 0.125 W/m·K, and a relative permittivity of less than 6.