Patent ID: 7258091

Claim:
A rocker arm capable of being driven by a cam for selectively opening and closing a valve mounted on a cylinder head of a combustion engine, the rocker arm comprising: a generally elongated arm body having first and second ends opposite to each other and prepared by bending a single plate material to represent a generally U-shaped section including opposite side walls and a connecting wall bridging between the opposite side walls, an end portion of the connecting wall adjacent the second end of the arm body being formed with a pivot abutment area, to which a free end of a pivot support member is engaged; a cam follower roller rotatably mounted on a portion of the arm body generally intermediate between the first and second ends thereof for engagement with the cam; and a valve drive element mounted on the first end of the arm body for driving the valve; wherein an outer chamfered corner delimited between an outer surface of the connecting wall and an outer surface of each of the opposite side walls and formed by bending is deformed to represent a plastically deformed portion so formed by means of a plastic deformation technique that the outer chamfered corner represents a small radius of curvature, and the radius of curvature of the outer chamfered corner delimited between the outer surface of the connecting wall and the outer surface of each of the opposite side walls is smaller than 70% of the wall thickness of the arm body.