Patent ID: 6851403

Claim:
A valve drive mechanism, comprising: a rocker arm that is mountable on a cylinder head and is pivotable about a pivot axis that extends transverse to the rocker arm; a control unit that acts upon a first end of said rocker arm for actuating a poppet valve having a valve stem upon which a second end of said rocker arm acts; a support pin that is connectable to a cylinder head, wherein said rocker arm is held on said support pin between said first and second ends of said rocker arm; a bolt head disposed on said support pin on a side of said rocker arm remote from a cylinder head, wherein said bolt head serves for adjusting a bearing spacing between said rocker arm and a cylinder head for varying valve play; and a rotation preventing element that cooperates with said bolt head, wherein said rotation preventing element is provided with an arresting portion that engages said bolt head, and a support portion that conveys an adjustment moment away, wherein said rocker arm is a shaped part having lateral longitudinal walls, at least one of which forms said arresting portion.