Dual compression and dual expansion internal combustion engine and method therefor

A method of burning a mixture of combustible fuel and air in an engine (8) including a housing (10), piston means (56) reciprocally mounted in the housing (10) and partially defining an intake chamber (144) having a variable volume, an exhaust chamber (146) having a variable volume, and a combustion space (254) having a variable volume, a crankshaft (52) rotatably supported in the housing (10) and operatively connected to the piston means (56) for delivering power externally therefrom in response to combustion in the combustion space (254), the method having the steps comprising:

• i) moving the piston means (56) in the housing (10) increasing the volume of the intake chamber (144), inducting a charge of air into the intake chamber (144) and reducing the volume in the exhaust chamber (146), exhausting a charge of exhaust gas from the exhaust chamber (146), with all these steps occurring during the same time interval;
• ii) compressing another charge of air in the combustion space (254), introducing fuel into the combustion space (254) forming a combustible mixture with the another charge of air, igniting the combustible mixture, and forming a charge of expanding gas driving the piston means (56) transmitting the energy of expanding gas to the crankshaft (52), wherein these steps occur sequentially and during the time interval step W;
• iii) moving the piston means (56) in the housing compressing the charge of air in the intake chamber (144), and transferring the charge of expanding gas to the exhaust chamber (146) which drives the piston means (56), thus transmitting energy to the crankshaft (52), with all these steps occurring during the same time interval subsequent to the time interval of steps i and ii;
• and
• iiii) continuing to compress the charge of air in the intake chamber (144) while transferring the charge of compressed air into the combustion space (254) and expanding the charge of gas in the exhaust chamber (146), thus transmitting energy to the crankshaft (52), with all these steps occurring during the same time interval and subsequent to the time interval of step iii.