Patent ID: 6899061

Claim:
A novel sequence of thermodynamic processes comprising: operating a closed internal combustion engine cycle which contains one or more pairs of cylinders with their heads in close proximity and pistons moving in phase and having a cylinder-connecting valve mounted in-between said cylinder heads, which is closed while one piston compresses an air-fuel mixture to a knock free level while the other piston compresses air to a substantially higher pressure, so that at the end of their compression stroke, when the cylinder-connecting valve is opened, the high-pressure air will compress, heat and ignite the air-fuel mixture resulting in constant volume heat addition at top dead center, to a substantially higher pressure and thus thermal efficiency than possible with a spark ignition Otto cycle, and also higher efficiency then with a Diesel cycle, while during the power/expansion stroke, the cylinder-connecting valve remains open to assure equal pressure acting on both pistons.