Direct valve drive device

摘要

The valve drive device includes a valve drive plate (6) between a cam (5) and the valve stem (3a), sprung by a valve spring towards the cam. A threaded hole (12) in the valve drive plate, receives a threaded setting bolt (13). The force of a spring is applied to the setting bolt so that when the bolt turns, it moves towards the valve stem. There is an axial gap between the bolt and the hole thread to allow for the difference in thermal expansion between the cylinder head and the valve.