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Title: Lean-burn internal combustion gas engine

Patent ·
OSTI ID:6474007

An internal combustion engine is described with a four-stroke cycle adapted for use with gaseous fuel and air mixtures comprising a cylinder casting with a cylinder and coolant jacket surrounding the cylinder; a piston in the cylinder having a generally flat piston head surface and defining a combustion chamber, a crankshaft mounted in the casting, a piston rod drivably connected to the crankshaft, the piston in its top dead center position having its head surface substantially in alignment with the end of the cylinder; a cylinder head, the cylinder head and the cylinder casting having matching surfaces at a cylinder casting and cylinder head interface; the clearance between the piston head surface and the surface of the cylinder head being at least 0.73 percent of the piston diameter but less than 2 percent of the piston diameter and defining a gas charge squish portion of the combustion chamber; a high ratio combustion chamber in the cylinder head having a depth greater than the clearance between the piston and the cylinder head surface and an area less than 40 percent of the cylinder area and more than 15 percent of the cylinder area; a gas charge inlet valve in the combustion chamber at a location that is isolated from the high ratio combustion chamber portion for admitting a gas charge to the combustion chamber; and an exhaust valve in the high ratio combustion chamber portion; the high ratio combustion chamber portion having contiguous gas turbulence regions defined by a kidney-shaped wall in the cylinder head, the wall having a convex curvature portion at one side thereof with a radius of curvature approximately equal to the radius of the cylinder and having a concave curvature portion at the opposite side thereof with a smaller radius of curvature, the exhaust valve being located at one of the gas turbulence regions, and a spark plug in the cylinder head at another of the gas turbulence regions, the concave curvature portion encircling the inlet valve.

Assignee:
Gas Research Inst., Chicago, IL (United States)
Patent Number(s):
US 5230321; A
Application Number:
PPN: US 7-917764
OSTI ID:
6474007
Resource Relation:
Patent File Date: 21 Jul 1992
Country of Publication:
United States
Language:
English