Lightweight rocker arm

Abstract

A rocker arm of the cam follower type has a rocker arm body formed of a metal matrix composite material comprising a lightweight metal, preferably aluminum, having ceramic material mixed therein. The rocker arm may take the form of a "slider" arm which included a pad for slideably engaging a cam on a rotating cam shaft for pivotally moving the rocker arm to operate an associated valve. For a slider rocker arm, the cam engaging pad comprises a wear resistant ceramic material which may be integrally formed into the rocker arm or otherwise secured thereto after forming. Alternately, the rocker arm may take the form of a "roller" rocker arm wherein a roller formed of a first ceramic material is rotatably mounted on an axle formed of a second ceramic material and mounted between sidewalls of the rocker arm body. One or both ceramic materials may be porous and self-lubricating when impregnated with a solid or liquid lubricant. A variety of hardening techniques, coatings and inserts may be provided as required.

Dependencies are inferred from the claim text.