Patent ID: 7204225
Filing Date: 2007-04-17
Classification: F02B,Y02T

Abstract:
1. An internal combustion engine comprising: a main combustion chamber having a variable volumetric capacity; an auxiliary combustion chamber; a communication passage extending along a relative travel direction of a barycenter of the main combustion chamber to provide fluid communication between the main combustion chamber and the auxiliary combustion chamber; a mixture formation section to locally form a relatively rich air-fuel mixture around an opening of the communication passage in the main combustion chamber; and an ignition unit to ignite an air-fuel mixture in the auxiliary combustion chamber which is supplied from the relatively rich air-fuel mixture in the main combustion chamber in accordance with a decrease in the volumetric capacity of the main combustion chamber, to produce a combustion flame to propagate through the communication passage into the relatively rich air-fuel mixture in the main combustion chamber, wherein the main combustion chamber includes enough space around the opening of the communication passage for the combustion flame to propagate through, when the volumetric capacity of the main combustion chamber is minimum, wherein the internal combustion engine further comprises a cylinder and a piston reciprocable in the cylinder, wherein the main combustion chamber is defined by the cylinder and the piston, wherein the decrease in the volumetric capacity of the main combustion chamber is caused by an upward motion of the piston, wherein the mixture formation section comprises a fuel injection valve configured to spray fuel into the main combustion chamber on a compression stroke of the engine and to form the relatively rich air-fuel mixture, wherein the piston includes a crown portion including a cavity, wherein the fuel injection valve is configured to spray fuel toward a bottom portion of the cavity, and wherein the cavity is formed in such a manner to guide the sprayed fuel toward the auxiliary combustion chamber.