Method and apparatus for attenuating fuel pump noise in a direct injection internal combustion chamber

A method of dampening transmission of fuel pump vibration to an engine block in a direct injection internal combustion engine having a fuel rail connected to the fuel pump and at least one direct injection fuel nozzle having a main body comprising the steps of:

• suspending the direct injection nozzle from the fuel rail so that a portion of the direct injection nozzle is positioned within an engine block passageway without direct contact with the engine block, and
• fluidly sealing the direct injection nozzle to the engine block with a seal,
• wherein the direct injection nozzle includes a fuel inlet and further comprising the steps of:
• providing a pair of axially spaced apart O-rings around the main body of the direct injection fuel nozzle so that the O-rings form an annular fluid chamber around the main body of the direct injection nozzle, the fuel inlet of the nozzle being in direct fluid communication with the annular fluid chamber, and
• directly fluidly connecting the annular fluid chamber with the fuel rail.

For use in conjunction with a direct injection internal combustion engine having at least one fuel rail, an engine block, a combustion chamber in the engine block and a passageway in the engine block to the combustion chamber, a direct injection nozzle assembly comprising:

• a direct injection fuel nozzle having a main body with a fuel inlet and a tip with a fuel outlet,
• an injector cup secured to the fuel rail, said injector cup having an open end cavity in fluid communication with the fuel rail and dimensioned to receive a portion of said main body of said fuel injector,
• an injector holder assembly which secures said fuel injector to the injector cup so that said nozzle tip of said fuel injector is positioned within but spaced from the engine block passageway, and
• a pair of spaced seals disposed around said main body of said fuel injector within said injector cup cavity, said seals each having an outer surface in sealing contact with said injector cup and wherein said seals form an annular fluid chamber between said injector cup and said fuel injector, said injector fuel inlet and the fuel rail both being directly fluidly connected to said annular fluid chamber.