What does rocker arm mean?

Definitions for rocker arm
rocker arm

This dictionary definitions page includes all the possible meanings, example usage and translations of the word rocker arm.

Princeton's WordNet

  1. rocker arm, valve rockernoun

    a lever pivoted at the center; used especially to push a valve down in an internal-combustion engine


  1. Rocker arm

    In the context of an internal combustion engine, a rocker arm is a valvetrain component that typically transfers the motion of a pushrod to the corresponding intake/exhaust valve. Rocker arms in automobiles are typically made from stamped steel, or aluminum in higher-revving applications. Some rocker arms (called roller rockers) include a bearing at the contact point, to reduce wear and friction at the contact point.


  1. rocker arm

    A rocker arm is a hinged lever in an internal combustion engine that translates the rotational motion from the camshaft to vertical or linear motion in order to open and close the intake and exhaust valves. It plays a critical role in the functioning of the engine, ensuring optimal timing for the flow of air and fuel mixture into the cylinder and evacuation of exhaust gases.


  1. Rocker arm

    Generally referred to within the context of the internal combustion engine of automotive, marine, motorcycle and reciprocating aviation engines, the rocker arm is an oscillating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it. One end is raised and lowered by a rotating lobe of the camshaft while the other end acts on the valve stem. When the camshaft lobe raises the outside of the arm, the inside presses down on the valve stem, opening the valve. When the outside of the arm is permitted to return due to the camshafts rotation, the inside rises, allowing the valve spring to close the valve. The drive cam is driven by the camshaft. This pushes the rocker arm up and down about the trunnion pin or rocker shaft. Friction may be reduced at the point of contact with the valve stem by a roller cam follower. A similar arrangement transfers the motion via another roller cam follower to a second rocker arm. This rotates about the rocker shaft, and transfers the motion via a tappet to the poppet valve. In this case this opens the intake valve to the cylinder head. The effective leverage of the arm is determined by the rocker arm ratio, the ratio of the distance from the rocker arm's center of rotation to the tip divided by the distance from the center of rotation to the point acted on by the camshaft or pushrod. Current automotive design favors rocker arm ratios of about 1.5:1 to 1.8:1. However, in the past smaller positive ratios and even negative ratios have been used. Many pre-WW2 engines use 1:1 ratios.

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  1. Chaldean Numerology

    The numerical value of rocker arm in Chaldean Numerology is: 1

  2. Pythagorean Numerology

    The numerical value of rocker arm in Pythagorean Numerology is: 3


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"rocker arm." Definitions.net. STANDS4 LLC, 2024. Web. 19 May 2024. <https://www.definitions.net/definition/rocker+arm>.

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