External compression ignition system for internal combustion engines

Abstract

To increase the fuel efficiency and decrease the emissions of current types of internal combustion engines by improving the burning of leaner fuel mixtures, a novel igniter is provided for each combustion chamber of the engine. The igniter comprises a small external chamber into which small charges of auxiliary fuel are valved, mixed with air, and then rapidly compressed to ignition temperature by a miniature piston or ram. From each of these external chambers a small orifice leads to its corresponding engine combustion chamber. The small size of the orifice restricts the exit flow into this engine combustion chamber of the auxiliary air/fuel mixture, permitting effective compression by the rapid action of the ram. The orifice may be so shaped that the limited amount of auxiliary air/fuel mixture which passes through it prior to ignition is ultrasonically mixed and shaped in order to provide, upon ignition, a geographically desirable flame pattern in the engine combustion chamber which effectively ignites the lean main charge. The igniter compression chamber may be of small volume, e.g. 1 cc. Its piston or ram may be actuated by solenoid means with reasonable electric power consumption. Auxiliary fuel may be valved to these chambers by low-pressure electrically actuated fuel injection valves of known type. The system may be manufactured as a retrofit kit for existing engines, in which case the external compression igniter assemblies may be screwed into the spark plug holes as the spark plugs are no longer required.

Dependencies are inferred from the claim text.