Patent ID: 7628126

Claim:
An 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 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 during a single rotation of the crankshaft; and 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, the outlet valve permitting substantially one way flow of gas from the pressure chamber to the first cylinder; wherein the power piston descends to a firing position between 10 and 40 degrees from its top dead center position.