Patent ID: 8826773

Claim:
A forged crankshaft comprising: a first end adapted for connection to an associated pulley and a second end adapted for connection to an associated flywheel; a plurality of main journals; a plurality of crank pin journals rotatable in a circular path about axes defined by the main journals; and a plurality of crank webs, at least one crank web of the plurality of crank webs defining a middle crank web which is located between and connecting two neighboring crank pin journals of the plurality of crank pin journals, the middle crank web having a stress relief forged therein, the forged-in stress relief being defined by first and second spaced sidewalls, an inner wall and a base wall, the forged-in stress relief having a predetermined depth, wrap angle, radius, and undercut which together define a shape of the forged-in stress relief, wherein the shape of the forged-in stress relief is controlled to reduce stress in the crankshaft, wherein the forged-in stress relief is located in an overlap area defined by the neighboring crank pin journals.