Patent ID: 8082908
Filing Date: 2011-12-27
Classification: F01L,F02B,F02F,F02M,Y02T

Abstract:
1. A variable air-fuel ratio (AFR), lean burn internal combustion (IC) engine system for igniting, combusting, and expanding a burnt air-fuel mixture and producing work comprising: a movable piston within a cylinder that has a cylinder head with single intake and single exhaust valve openings with the combustion chamber located mainly in the head, and wherein the exhaust valve stem is vertical (with the exhaust valve horizontal) and has approximately 65% of the combustion chamber volume in a cup-like volume essentially under the exhaust valve comprising part of the roof of the combustion chamber, and the intake valve comprises an element subtending from the roof to near the intersection of the cylinder wall and the piston at top center (TC) to make a triangular shape, and further including two squish lands for producing high squish-flow and turbulence as the piston nears TC on the engine compression stroke, the system constructed and arranged to have two spark plugs positioned and oriented such that as the piston approaches top center, intense air-flow passes through or near the spark gaps to move and spread the spark towards the cup-like region under the hotter exhaust valve, and further comprising means for improving the lean burn capability of the engine under light load conditions and the knock rating under high loads wherein at least two spark plugs have flexibility relative to each other in terms of ignition firing and timing.