Patent ID: 6845746

Claim:
An internal combustion engine fueled with a combustible gaseous fuel, said engine comprising: at least one combustion chamber defined by a cylinder, a piston reciprocable within said cylinder, and a cylinder head that covers an end of said cylinder; an ignition device with an end disposed within said combustion chamber, said ignition device comprising an igniter that is heatable to provide a hot surface and a sleeve surrounding said igniter, said sleeve defining a shielded space between said igniter and said sleeve; a fuel injection valve disposed within said combustion chamber, said fuel injection valve being operable to introduce said combustible gaseous fuel into said combustion chamber with a plurality of fuel sprays each released from one of a plurality of fuel injection ports, wherein one of said plurality of fuel injection ports is oriented to direct a fuel spray, referred to as an ignition fuel spray, towards an impingement point on said sleeve; an intake opening provided through said sleeve near said impingement point connecting said shielded space to said combustion chamber whereby, when said ignition fuel spray impacts said impingement point, a portion of said combustible gaseous fuel contained within said ignition fuel spray passes through said intake opening and into said shielded space; a discharge opening provided through said sleeve, spaced further from said impingement point than said intake opening, wherein said discharge opening is oriented to direct a burning fuel-air mixture from said shielded space and towards roots of said plurality of fuel sprays near said fuel injection valve; and wherein said sleeve restricts flow between said shielded space and said combustion chamber so that a substantial portion of said combustible gaseous fuel is retained within said shielded space until combustion of said combustible gaseous fuel within said shielded space produces a pressure therein that is higher than the pressure within the combustion chamber and said pressure is high enough to propel said burning fuel-air mixture into said combustion chamber and into contact with said roots of said plurality of the fuel sprays.