Rocker arm

Abstract

A rocker arm swingably supported by an arm shaft and operating a valve by rotation of a cam includes an arm body part including a bearing portion supported by the arm shaft, a cam-side arm portion extending from the bearing portion toward a first side, and a valve-side arm portion extending from the bearing portion toward a second side, an arch part extending over the bearing portion and connecting the cam-side arm portion and the valve-side arm portion, and a lightweight part disposed in a space defined between the arm body part and the arch part and having a reduced weight compared with a case where the space is filled with the same material at the same thickness as the arch part.

Dependencies are inferred from the claim text.