Patent ID: 7484487

Claim:
A valve control system for an internal combustion engine of the type including a cylinder head, and a poppet valve moveable relative to the cylinder head between open and closed positions, and a camshaft having a first cam profile and a second cam profile formed thereon; said valve system comprising a rocker arm assembly including a first rocker arm having a first cam follower in engagement with the first cam profile, and a second rocker arm having a second cam follower in engagement with the second cam profile; said valve control system further comprising the cylinder head including a fulcrum location operable to provide a source of pressurized fluid; said first rocker arm defining, toward a first axial end thereof, a fulcrum surface, adapted for pivotal engagement with said fulcrum location; said first rocker arm further defining, adjacent said fulcrum surface a pivot location whereby said second rocker arm pivots relative to said first rocker arm about said pivot location; said first rocker arm includes, toward a second axial end thereof, a latch assembly including a latch member moveable between latched and unlatched conditions relative to a latch surface defined by an adjacent portion of said second rocker arm; a spring biasing said latch member toward one of said latched and unlatched conditions, and said latch assembly defining a pressure chamber ( 51 ) operable to bias said latch member toward the other of said latched and unlatched conditions; characterized by: said rocker arm assembly comprising a means for biasing said first rocker arm toward an out-of-latching-contact condition, relative to said second rocker arm; said first rocker arm defining a fluid passage having a first end in open fluid communication with said fulcrum surface, said first end of said fluid passage being operable to receive pressurized fluid from said source; and said fluid passage having a second end in open fluid communication with said pressure chamber of said latch assembly.