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US 2012/0234285 A1Published application
Piston for internal combustion engine
AssigneeCummins Intellectual Property, Inc.
InventorsRishikesh VENUGOPAL, Donald W. STANTON, Bhargav RANGANATH, Thomas GEYER
Life of this patent
Estimating the term…
Abstract
A piston and an engine are provided that includes various precise configuration parameters, including dimensions, shape and/or relative positioning of combustion chamber features. More particularly, configuration parameters for a piston crown and a piston bowl located within the piston crown are provided. The piston bowl configuration results in a combustion process that yields decreased heat transfer to a cylinder head of the internal combustion engine as well as reduced NOx emissions.
Claims20
An internal combustion engine, comprising:
- an engine body;
- a cylinder head attached to the engine body;
- a combustion chamber positioned between the cylinder head and the engine body;
- and
- a piston, including a piston crown that forms a portion of the combustion chamber, located in the engine body, the piston crown including a central axis, a plurality of valve pockets arranged about the periphery of the piston crown in a plane perpendicular to the central axis, and a piston bowl positioned radially inward from the valve pockets, the piston bowl including:
- a compound radius including a radius R1, radius R1 including a center of radius at a radial distance L1 from the central axis, radius R1 connected to and extending inwardly from the valve pockets;
- a frustoconical outer floor portion connected to the compound radius, the frustoconical outer floor portion extending a distance L4 from the compound radius at an angle α1 to a plane perpendicular to the central axis;
- an annular outer bowl portion including a radius R5;
- and a spray-targeting feature positioned between the annular outer bowl portion and the frustoconical outer floor portion and including a radius R3 with a center of radius located at an axial distance H3 from the valve pockets.
6 more elements
An internal combustion engine, comprising:
- an engine body;
- a cylinder head attached to the engine body;
- a combustion chamber positioned between the cylinder head and the engine body;
- and
- a piston, including a piston crown that forms a portion of the combustion chamber, located in the engine body, the piston crown including a central axis, a plurality of valve pockets arranged about the periphery of the piston crown in a plane perpendicular to the central axis, and a piston bowl positioned radially inward from the valve pockets, the piston bowl including:
- a compound radius including a radius R1, radius R1 including a center of radius at a radial distance L1 from the central axis, radius R1 connected to and extending inwardly from the valve pockets;
- a frustoconical outer floor portion connected to the compound radius, the frustoconical outer floor portion extending a distance L4 from the compound radius at an angle α1 to a plane perpendicular to the central axis;
- an annular outer bowl portion;
- and a spray-targeting feature positioned between the annular outer bowl portion and the frustoconical outer floor portion and including a radius R3 with a center of radius located at an axial distance H3 from the end surface;
- wherein a ratio L4/R3 is in the range of 0.2 to 3.0 and a ratio H3/L1 is in the range of 0.15 to 0.3.
7 more elements
An internal combustion engine, comprising:
- an engine body;
- a cylinder head attached to the engine body;
- a combustion chamber positioned between the cylinder head and the engine body;
- and
- a piston, including a piston crown that forms a portion of the combustion chamber, located in the engine body, the piston crown including a central axis, a plurality of valve pockets arranged about the periphery of the piston crown in a plane perpendicular to the central axis, and a piston bowl positioned radially inward from the valve pockets, the piston bowl including:
- a compound radius connected to and extending inwardly from the valve pockets;
- a frustoconical outer floor portion connected to the compound radius, the frustoconical outer floor portion extending from the compound radius at an angle α1 to a plane perpendicular to the central axis;
- an annular outer bowl portion including a radius R5;
- a spray-targeting feature positioned between the annular outer bowl portion and the frustoconical outer floor portion;
- and a ski jump feature positioned between the annular outer bowl portion and the central axis and connected to the annular outer bowl portion, the ski jump feature including a radius R4;
- wherein a ratio R4/R5 is in the range of 2.5 to 5.0.
8 more elements
Dependencies are inferred from the claim text.