Rocker (valve actuator lever) is a structural element of the valve actuator mechanism. There is also the name of the roller lever or rocker arm. The task of the rocker is to transfer force from the camshaft cam to the valve stem (stem) when the camshaft is in the upper position. This solution in the valve drive device provides the timing belt with a lower mass and reduces friction.
The rocker arm (valve rocker) takes over the translational movement of the pusher rod and transmits this movement to the valve stem. The initial force is transmitted from the camshaft cam. Rockers are located at the top of the cylinder head. An axle is pressed into the central part of the rocker, which is fixed using two support pins of the rocker arm. The support pins are inserted into special struts, which, in some design variants, are made in the cylinder head housing.
On the one hand, the rocker armrests on the valve stem, and on the other, it can rest on the hydraulic compensator. Some valve actuator designs require the rocker to be supported on a special ball joint. The place of contact between the rocker and the camshaft cam is made in a roller.
Rocker arms in modern engines are gradually being eliminated from the timing device due to the active use of an overhead camshaft design. The main purpose of using rockers today is to reduce the size of the motor. This may be necessary to place the internal combustion engine in the engine compartment of a small car.
A rocker is a lever that has two “arms” (double-arm). The rocker arm is made by steel forming, casting or forging. The latter option is more preferable since forged elements have increased strength. Forged rockers are mounted on powerful powertrains.
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