Internal combustion engine and working cycle

Abstract

The invention is concerned with a method of deriving mechanical work from a combustion gas in internal combustion engines and reciprocating internal combustion engines for carrying out the method. The invention includes methods and apparatuses for managing combustion charge densities, temperatures, pressures and turbulence in order to produce a true mastery within the power cylinder in order to increase fuel economy, power, and torque while minimizing. polluting emissions. In its preferred embodiments, the method includes the steps of (i) producing an air charge, (ii) controlling the temperature, density and pressure of the air charge, (iii) transferring the air charge to a power cylinder of the engine such that an air charge having a weight and density selected from a range of weight and density levels ranging from below atmospheric weight and density to heavier-than-atmospheric weight and density is introduced into the power cylinder, and (iv) then compressing the air charge at a lower-than-normal compression ratio, (v) causing a pre-determined quantity of charge-air and fuel to produce a combustible mixture, (vi) causing the mixture to be ignited within the power cylinder and (vii) allowing the combustion gas to expand against a piston operable in the power cylinders with the expansion ratio of the power cylinders being substantially greater than the compression ratio of the power cylinders of the engine. In addition to other advantages, the invented method is capable of producing mean effective cylinder pressures ranging from lower-than-normal to higher-than-normal. In the preferred embodiments, the mean effective cylinder pressure is selectively variable (and selectively varied) throughout the mentioned range during the operation of the engine. In an alternate embodiment related to constant speed-constant load operation, the mean effective cylinder pressure is selected from the range and the engine is configured, in accordance with the present invention, such that the mean effective cylinder pressure range is limited, being varied only in the amount required for producing the power, torque and speed of the duty cycle for which the engine is designed.

1 . A four-stroke, reciprocating, internal combustion engine including at least one chamber with at least one intake port associated therewith, a piston partially defining said chamber and being movable in a reciprocating manner within a cylinder through a plurality of power cycles, each power cycle involving four strokes resulting from two rotations of a crankshaft and including an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke, aided by combustion taking place within the chamber, said engine comprising:
 at least one air intake port and at least one exhaust port associated with said chamber;   at least one air intake valve controllably movable to open and close said at least one air intake port;   at least one compressor being in fluid communication with atmosphere and with said at least one air intake port;   at least one air cooler in fluid communication between said at least one compressor and said at least one air intake port;   a fuel delivery system; and   a controller configured to selectively operate said at least one air intake valve to keep said at least one intake port open for a portion of the intake stroke and beyond the end of the intake stroke and into the compression stroke and for a majority portion of the compression stroke.   
   
   
       2 . The engine of  claim 1 , wherein the at least one compressor comprises a first compressor being in fluid communication with said at least one air intake port and a second compressor being in fluid communication with atmosphere and said first compressor. 
   
   
       3 . The engine of  claim 1 , wherein at least one of said first compressor and said second compressor is coupled with a turbine of a turbocharger, said turbine being in fluid communication with said exhaust port. 
   
   
       4 . The engine of  claim 1 , wherein said fuel delivery system includes a fuel injector assembly. 
   
   
       5 . The engine of  claim 1 , said at least one air cooler including a first air cooler for cooling the air compressed by said second compressor. 
   
   
       6 . The engine of  claim 5 , said at least one air cooler including a second compressor for cooling the air compressed by said first compressor. 
   
   
       7 . The engine of  claim 1 , wherein said variable valve mechanism is actuated electronically. 
   
   
       8 . The engine of  claim 2 , further including an air cooler between at least one of said first compressor and said second compressor and said at least one air intake port. 
   
   
       9 . The engine of  claim 1 , wherein said fuel delivery system is operable to controllably inject fuel into said chamber during a compression stroke, after said at least one intake port is closed. 
   
   
       10 . The engine of  claim 1 , wherein said fuel delivery system is operable to controllably inject fuel into said chamber during a combustion stroke. 
   
   
       11 . The engine of  claim 1 , wherein said fuel delivery system is operable to controllably introduce fuel into said chamber through said at least one intake port while said at least one intake port is open. 
   
   
       12 . The engine of  claim 1 , wherein said fuel delivery system is operable to controllably introduce fuel to an intake port of said at least one compressor. 
   
   
       13 . The engine of  claim 1 , further comprising an exhaust gas recirculation system operable to controllably provide a portion of exhaust gas from said exhaust port to an intake of said at least one compressor. 
   
   
       14 . The engine of  claim 13 , wherein said fuel delivery system is operable to controllably inject fuel into said chamber during a compression stroke, after said at least one intake port is closed. 
   
   
       15 . The engine of  claim 13 , wherein said fuel delivery system is operable to controllably inject fuel into said chamber during a combustion stroke. 
   
   
       16 . The engine of  claim 13 , wherein said fuel delivery system is operable to controllably introduce fuel into said chamber through said at least one intake port while said at least one intake port is open. 
   
   
       17 . The engine of  claim 13 , wherein said fuel delivery system is operable to controllably introduce fuel to an intake port of said at least one compressor. 
   
   
       18 . The engine of  claim 13 , wherein the at least one compressor comprises at least two compressors providing at least two stages of compression to air and exhaust gas upstream of said at least one air intake port. 
   
   
       19 . The engine of  claim 18 , wherein the at least one compressor comprises at least three compressors providing at least three stages of compression to air and exhaust gas upstream of said at least one air intake port. 
   
   
       20 . The engine of  claim 18  or  19 , including a cooler positioned in flow communication after each stage of compression. 
   
   
       21 . The engine of  claim 1 , wherein the piston is driven in a reciprocating motion by a crank on a crankshaft, the engine being so constructed that the piston is at top dead center of its path when the crank is at bottom dead center on the crankshaft. 
   
   
       22 . The engine of  claim 1 , wherein the piston is driven in a reciprocating motion by the action of a crank acting directly or indirectly on a crank pin to which is attached a connecting rod to which is connected the piston, and wherein the engine is so constructed and arranged that, when the piston is around top dead center of its motion, the crank pin motion is subtracted from the straightening movement of the connecting rod. 
   
   
       23 . The engine of  claim 1 ,  9  or  11 , wherein said first controller is configured to selectively operate said air intake valve to keep said at least one air intake port open for greater than 90% crank angle after bottom dead center. 
   
   
       24 . The engine of  claim 1 ,  9  or  11 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 65% of the compression stroke. 
   
   
       25 . The engine of  claim 1 ,  9  or  11 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 70% of the compression stroke. 
   
   
       26 . The engine of  claim 1 ,  9  or  11 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 80% of the compression stroke. 
   
   
       27 . The engine of  claim 13 ,  14  or  16 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 85% of the compression stroke. 
   
   
       28 . The engine of  claim 13 ,  14  or  16 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 65% of the compression stroke. 
   
   
       29 . The engine of  claim 13 ,  14  or  16 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 70% of the compression stroke. 
   
   
       30 . The engine of  claim 13 ,  14  or  16 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 80% of the compression stroke. 
   
   
       31 . The engine of  claim 13 ,  14  or  16 , wherein said first controller is configured to selectively operate said at least one air intake valve to keep said at least one air intake port open for at least 85% of the compression stroke. 
   
   
       32 . The engine of  claim 1 , wherein at least one intake valve comprises a shrouded valve. 
   
   
       33 . The engine of  claim 1 , further comprising a shunt conduit between said exhaust port and an intake of said at least one compressor; and a proportioning valve associated with said shunt conduit. 
   
   
       34 . The engine of  claim 33 , including a cooler associated with said shunt conduit.