DK28 diesel engine accessories rocker shaft

What is a rocker shaft?

The rocker arm shaft belongs to the upper part of the engine valve train. The valve mechanism of some ships requires a rocker arm to drive the valve, so the fixation of the rocker arm requires the rocker arm shaft to be connected in series and then fixed to the cylinder head.

First, it is used to fix the rocker arm. Second, the rocker arm is a lever, and the rocker arm shaft is the fulcrum. The rocker arm rotates at a certain angle around the rocker arm axis to push the valve to move.

Working principle of rocker shaft of marine diesel engine parts:

1. Under the action of the rotating blade of the camshaft, one end is raised or lowered (directly or through the gear follower (lifting rod) and push rod), and the other end will act on the valve stem. When the lobe of the camshaft lifts the outer lever arm, the internally generated force will press on the valve stem, opening the action valve. When the outer arm is allowed to return due to the action of the camshaft, the inner arm rises, allowing the valve spring to compress to close the action valve.

2. The driving cam is driven by the camshaft. It can push the rocker arm to move up and down near the trunnion or rocker axis. This reduces wear on the drive cam at the point of contact with the valve stem by the roller follower of the cam. At the same time, a similar movement is transmitted to the second rocker arm through the action of another cam roller follower. This rotates the rocker shaft and transfers the action to the poppet valve through the gear follower. In this case, the intake valve is opened, allowing the gas to rush towards the cylinder head.