Patent ID: 8550044

Claim:
An internal combustion engine comprising: a crankcase; a cylinder block connected to the crankcase, the cylinder block defining a cylinder; a piston disposed in the cylinder; a crankshaft disposed in the crankcase and operatively connected to the piston; a cylinder head connected to the cylinder block, the cylinder head, the cylinder and the piston defining a combustion chamber therebetween; at least one camshaft disposed in the cylinder head and operatively connected to the crankshaft; at least one intake passage fluidly communicating with the combustion chamber; at least one intake valve disposed in the at least one intake passage, the at least one intake valve selectively communicating the at least one intake passage with the combustion chamber; a first spring operatively connected to the at least one intake valve, the first spring biasing the at least one intake valve to a closed position preventing fluid communication between the at least one intake passage and the combustion chamber; at least one exhaust passage fluidly communicating with the combustion chamber; at least one exhaust valve disposed in the at least one exhaust passage, the at least one exhaust valve selectively communicating the at least one exhaust passage with the combustion chamber; a second spring operatively connected to the at least one exhaust valve, the second spring biasing the at least one exhaust valve to a closed position preventing fluid communication between the at least one exhaust passage and the combustion chamber, at least one of the first and second springs being an air spring; at least one intake cam and at least one exhaust cam disposed on the at least one camshaft, the at least one intake cam engaging the at least one intake valve, and the at least one exhaust cam engaging the at least one exhaust valve; an air compressor fluidly communicating with the air spring to supply air to the air spring, the air compressor being operatively connected to the at least one camshaft, the at least one camshaft selectively driving the air compressor; and a motor operatively connected to the air compressor, the motor selectively driving the air compressor.