Internal combustion engine

In an internal combustion engine including a crankshaft, a cylinder, a cylinder head, a piston reciprocably mounted in said cylinder, means drivingly connecting said piston to said crankshaft, a combustion chamber defined and bounded by said cylinder, said cylinder head, and said piston, means defining inlet ports and outlet ports for said combustion chamber, air intake means, means defining an inlet duct for conducting air fro said air intake means to said inlet ports for supply to said combustion chamber for combustion with fuel to drive said piston and hence said crankshaft, and means defining an exhaust duct communicating with said exhaust ports for conducting post combustion gases away from said combustion chamber, the improvement wherein said engine further includes an air compressor between said air intake means and said inlet duct whereby said air conducted by said inlet duct is compressed, a plurality of passage means leading from said inlet duct and extending in said engine closely around said combustion chamber whereby compressed air flows through said passage means from said inlet duct to extract heat from said engine surrounding said combustion chamber, and a turbine having a power output shaft, rotor means attached to said power output shaft, and high pressure gas inlet means communicating with said exhaust duct and said passage means whereby hot compressed gases from said combustion chamber and said passage means expand through said turbine to drive said rotor means and hence said power output shaft.