Fuel injection
AssigneeFord Global Technologies, LLC
InventorJialin Yang
Life of this patent
Estimating the term…
Abstract
A stratified charge is formed in an engine by injecting fuel at an impingement surface adjacent an outlet of the injector. The injected fuel thereby forms a cloud shallowly penetrating the combustion chamber so as to float therein to reduce wall-wetting and subsequent soot formation. A substantially flat top piston urges the cloud upwardly during a compression stroke of the engine. The cloud remains substantially unmixed with the inducted air, thereby producing the stratified charge. The continued motion of the piston causes the cloud to move toward the spark plug for ignition.
Claims23
The method of forming a combustible fuel mixture for a spark ignition internal combustion engine, the engine having a cylinder block with a plurality of cylinder bores formed therein, the cylinder bore defining a longitudinal axis, a plurality of substantially flat top pistons each reciprocally housed within a cylinder bore, a cylinder head attached to the block and closing top ends of the bores to form a plurality of combustion chambers, an intake port formed in the cylinder head and communicating with the combustion chamber via an intake valve for introducing air into the combustion chamber, a fuel injector, defining an axis and communicating with the combustion chamber, for supplying fuel into the combustion chamber, and an ignition source communicating with the combustion chamber for igniting fuel within the combustion chamber, with said method comprising the steps of:
- injecting fuel from the fuel injector having an outlet and a predetermined initial cone angle, into the engine at a predetermined velocity, said injected fuel impinging on a surface adjacent the outlet of said injector thereby forming a cloud shallowly penetrating the combustion chamber so as to float therein to reduce wall wetting, said impingement surface having a substantially spherical surface positioned approximately 1.25 mm from the outlet of said injector so substantially all of said jet strikes said surface;
- urging said cloud upwardly in said combustion chamber with said substantially flat top piston during a compression stroke of the engine;
- wherein said mixture comprises a stratified mixture and said cloud defines a relatively rich region and the remainder of the volume of the combustion chamber defines a lean region, with said fuel remaining substantially unmixed with said inducted air, thereby producing said stratified charge as said piston moves said cloud toward said ignition source.
A fuel injected, spark ignition combustion engine, comprising:
- a cylinder block;
- a cylinder bore formed in said cylinder block, with said bore defining a longitudinal axis and having a top end;
- a cylinder head attached to said block and closing said top end of said bore to form a combustion chamber;
- an intake port formed in said cylinder head and communicating with said combustion chamber via an intake valve for inducting air into said combustion chamber;
- a fuel injector, defining an axis, for injecting fuel into said combustion chamber, said injector having an outlet for injecting said fuel at a predetermined velocity and formed into a cone having a predetermined initial cone angle;
- an impingement surface comprising a substantially spherical surface provided approximately 1.25 mm from said outlet of said injector, with said injected fuel striking said impingement surface thereby forming a fuel cloud for shallowly penetrating into said combustion chamber so as to float therein to reduce wall wetting;
- and
- a substantially flat top piston reciprocally housed within a said bore;
- wherein said fuel remains substantially unmixed with said inducted air, thereby producing a stratified charge and wherein said cloud defines a relatively rich region and the remainder of the volume of the combustion chamber defines a lean region, with said substantially flat top piston urging said cloud upwardly during a compression stroke of the engine and an ignition source communicates with said combustion chamber with said cloud engulfing said ignition source so that said fuel is ignitable by said ignition source.
A stratified charge, direct injection, spark ignition internal combustion engine comprising:
- a cylinder block;
- a cylinder bore formed in said cylinder block, with said bore defining a longitudinal axis and having a top end;
- a cylinder head attached to said block and closing said top end of said bore to form a combustion chamber;
- an intake port formed in said cylinder head and communicating with said combustion chamber via an intake valve for inducting air into said combustion chamber;
- a fuel injector, defining an axis, for injecting fuel directly into said combustion chamber at a predetermined velocity and having a spray jet exiting an outlet of the injector;
- an impingement surface comprising a substantially spherical surface positioned approximately 1.25 mm from said outlet of said injector, said impingement surface having a size and positioned in close proximity to said outlet so substantially all of said jet strikes said surface, with said injected fuel thereby shallowly penetrating into said combustion chamber so as to form a cloud and float therein to reduce wall wetting;
- a substantially flat top piston reciprocally housed within said bore, with said substantially flat top piston causing said injected fuel to move upwardly during a compression stroke of the engine, with said fuel remaining substantially unmixed with said inducted air, thereby producing said stratified charge;
- and,
- an ignition source communicating with said combustion chamber, with said cloud engulfing said ignition source so that said fuel is ignitable by said ignition source.
Dependencies are inferred from the claim text.