Patent ID: 7383831
Filing Date: 2008-06-10
Classification: F02B,F02D,F02F,F02M,Y02T

Abstract:
1. A structure of a chamber in a combustion engine, comprising: a cylinder block of the engine having a cylinder in which a piston is reciprocatably disposed; a cylinder head of the engine disposed on the cylinder block; a chamber formed between a bottom surface of the cylinder head and a top surface of the piston; an intake port formed in the cylinder head for inducting air to the chamber; an exhaust port formed in the cylinder head for discharging exhaust gas from the chamber; an intake valve for selectably closing the intake port; an exhaust valve for selectably closing the exhaust port; a ring-groove portion, in which a piston ring is fitted, formed around a side-outer surface of the piston; a squish-area making portion, which is formed on the top surface and outer edge of the piston, for making narrow space as a squish-area defined between the bottom surface of the cylinder head and the top surface of the piston located in top dead center; a flat portion which is a flat surface formed on the top surface of the piston except said squish-area making portion; an outer edge portion formed around the top surface of the piston except said squish-area making portion; and a land portion, which is formed around a side surface of the piston between said ring-groove portion and the top surface of the piston, said land portion having wherein a height from said ring-groove portion to said squish-area making portion is larger than a height from said ring-groove portion to said outer edge portion, and wherein said flat portion is higher than said outer edge portion in height.