Piston-type internal combustion engine

Claim 1

An internal combustion engine including a cylinder; a piston movable therein; means including an intake valve for effecting the induction of a charge of fuel air mixture into the cylinder; a control member movable to control the engine output; a variable valve timing device controlling the timing of the intake valve; a coupling between said movable control member and the variable timing device, said coupling varying the timing of the intake valve in response to the movement of the control member and thereby controlling the quantity of the fuel air mixture charge inducted into the cylinder; said piston including a floating crown such that the lowering of the gas pressure acting thereon upon an increase in the delay of closing the intake-valve, permits the crown, by virtue of the inertia force acting thereon, to move further inwardly into the cylinder at the end of the compression stroke than when the said delay is decreased, thereby causing the engine operation to approximate a substantially constant compression ratio operation notwithstanding variations in said valve closing delay and variations in the engine output; said piston further including a skirt coupled to the piston pin; and a spring connected at one end to the piston pin and at the opposite end to the piston crown, said spring acting with said inertia force to move the crown further inwardly into the cylinder at the end of the compression stroke.