Variable compression ratio internal combustion engine

Abstract

A variable compression ratio internal combustion engine is programmably configured to operate in a plurality of compression ratios. Internal combustion engines with electronically controlled engine components that include electronic valve operation are programmed to operate individual engine cylinders with component states and stoke sequences that provide variable compression ratios by creation of a virtual cylinder within a physical cylinder. Cylinder volume dictates maximum compression ratio, which acts as a ceiling for the variable compression ratio that can be provided.

1 . A variable compression ratio internal combustion engine configured to operate with a plurality of compression ratios comprising: 
 one or more cylinder units each with expanding and contracting cylinder volume and associated stroke sequences;    each cylinder unit having an electronically controllable intake valve component having multiple states under computer control;    each cylinder unit having an electronically controllable exhaust valve component having multiple states under computer control;    each cylinder unit having an electronic fuel injector component having programmable flow rate under computer control;    each cylinder unit having an air-fuel mixture ignition means for igniting an air-fuel mixture in the cylinder volume, said ignition means under computer control;    a computer usable medium containing the program control logic;    a computer control system comprising computer readable program control logic residing in the computer usable medium for controlling cylinder component states in concert with piston sweep of cylinder volume such that the swept cylinder volume corresponds to a virtual cylinder volume determined to yield the selected compression ratio, and    a cylinder unit intake and compression stroke sequence with a spring zone contained partially in the intake stroke and partially in the compression stroke for the purposes of allowing intake valve open duration variability for controlling volume of drawn air, wherein the spring zone comprises portions of strokes cylinder state pressure falls below the intake air pressure on the intake stroke segment following intake valve closure    whereby a rarefied mixture which is compressed to the target compression ratio on the following compression stroke yields a gas mixture with compression ratio equal to the selected compression ratio.    
   
   
       2 . A method of operating a programmable variable compression ratio internal combustion engine with at lest one cylinder unit having electronic controlled fuel injection component, electronic controlled air/fuel mixture igniter component, at least two electronic controlled cylinder valve components and reciprocating piston in the cylinder, comprising: 
 determining cylinder unit piston position;    determining intake valve open time and open duration corresponding to the desired cylinder compression ratio;    transitioning from one intake valve open time and duration state to another intake valve close time and duration state in synchronicity with cylinder piston intake stroke position in accordance executable code in programmable computer memory;    thereby altering operation of the cylinder unit by actuating cylinder component states from one compression ratio to another compression ratio.    
   
   
       3 . A method of operating a programmable variable compression ratio internal combustion engine as in  claim 2  further comprising starting the intake valve open state substantially at piston top dead center.  
   
   
       4 . A method of operating a variable compression ratio cylinder unit in an internal combustion engine with electronic controlled fuel injection component, electronic controlled air/fuel mixture ignition component, electronic controlled cylinder valve component combustion, the method comprising: 
 determining the piston position;    selecting an ignition mode;    determining the volume to be compressed for a selected compression ratio from cylinder dimensions and associated piston position to achieve the volume;    determining intake valve open state time and duration from piston TDC to fill determined volume; and    actuating intake valve open state time and duration based on required intake valve open state duration to achieve a virtual volume determined to provide the selected compression ratio,    thereby operating the cylinder unit in various compression ratios responsive to and programmably computer controlled.    
   
   
       5 . A method of operating a variable compression engine as in  claim 4  further comprising an electronic ignition mode chosen from a group consisting essentially of spark ignition, compression ignition, homogeneous charge compression ignition and duel fuel ignition.  
   
   
       6 . A method of operating a variable compression, direct fuel injection, electronic controlled ignition means, electronically controlled cylinder intake and exhaust valve, computer controlled system with programmable logic residing in programmable storage medium for execution of logic to control cylinder unit component states, internal combustion engine having a plurality of cylinder units with associated components whose states are individually controlled to create cylinder unique compression states whereby compression ratios for individual cylinder units can be independently sequenced and programmably controlled.