cam follower

Valve control via camshaft and drag lever

A drag lever (also a rocker arm) is a lever used in internal combustion engines to transfer cam movements of a cam from the camshaft to the intake or exhaust valves.

The drag lever is a one-sided lever. It is rotatably mounted on one side, on the other end it rests on the valve. In contrast to the arrangement for the rocker arm, the camshaft is located above the rocker arm. The camshaft actuates the drag lever from above without intermediate links. Variations with ball-bearing roller taps are also common. In the case of a roller towing lever, a bearing roller is provided in the engagement area of ​​the camshaft. This roller reduces the friction in the valve drive by about 30%. Typically, the valve spring will return the drag lever to its initial position as soon as the camshaft has continued to rotate. Some designs have a separate reset spring to return the drag lever to its initial position.

The forces acting on the drag lever are smaller compared to the rocker arm drive. A further advantage is the simple realization of a valve-type balancing. To compensate for the valve clearance, the center of rotation is adjusted vertically. The compensating elements do not count among the moving masses, the drag lever is only supported by this.

Lever levers are usually made of sheet steel or cast steel. Edit source text

wiki



wiki