Patent ID: 7404386

Claim:
A multi-step valve actuation system to selectively open a poppet valve of an internal combustion engine having a camshaft rotatably supported by a cylinder block, the multi-step valve actuation system comprising: a rocker arm operable to selectively open the poppet valve; a pushrod operable to bias said rocker arm; a first follower arm engageable with a first cam of the camshaft and operable to selectively bias said pushrod; a second follower arm engageable with a second cam of the camshaft and selectively latchable with respect to said first follower arm for unitary movement; a third follower arm engageable with a third cam of the camshaft and selectively latchable with respect to said first follower arm for unitary movement; wherein said first and second cam have respective first and second maximum valve lifts, said second maximum valve lift being greater in magnitude than said first maximum valve lift; wherein said third cam has a third maximum valve lift of greater magnitude than said first and second maximum valve lifts; wherein the poppet valve is opened to said third maximum valve lift when said third follower arm is latched to said first follower arm; wherein the poppet valve is opened to said first maximum valve lift when said second follower arm is unlatched from said first follower arm; and wherein the poppet valve is opened to said second maximum valve lift when said second follower arm is latched to said first follower arm.