Patent ID: 6722127
Filing Date: 2004-04-20
Classification: F02B,F02F

Abstract:
A four stroke cycle internal combustion engine comprising:a crankshaft, rotating about a crankshaft axis of the engine; a power piston slidably received within a first cylinder and operatively connected to the crankshaft such that the power piston reciprocates through a power stroke and an exhaust stroke of a four stroke cycle during a single rotation of the crankshaft; a compression piston slidably received within a second cylinder and operatively connected to the crankshaft such that the compression piston reciprocates through an intake stroke and a compression stroke of the same four stroke cycle during the same rotation of the crankshaft; a gas passage interconnecting the first and second cylinders, the gas passage including an inlet valve and an outlet valve defining a pressure chamber therebetween, wherein the inlet valve and the outlet valve of the gas passage substantially maintain at least a predetermined firing condition gas pressure in the pressure chamber during the entire four stroke cycle; an inlet manifold in fluid communication with an inlet valve for inputting air into the second cylinder when the compression piston reciprocates through an intake stroke; and a bypass valve in fluid communication with the second cylinder and the inlet manifold, wherein when the compression piston reciprocates through a compression stroke the bypass valve allows a portion of the air to bypass the inlet valve and exhaust into the inlet manifold to provide a variable compression ratio.