Patent ID: 8533946

Claim:
A method of manufacturing a crankshaft, the method comprising: positioning a single core within a cavity of a mold having a first half and a second half forming an exterior shape of the crankshaft, wherein the exterior shape of the crankshaft includes a plurality of pin bearing journals and a plurality of main bearing journals; introducing a molten metal into the cavity to form the crankshaft, wherein the molten metal flows into the cavity and around the single core to simultaneously form a hollow section extending through at least one of the plurality of pin bearing journals and at least one of the plurality of main bearing journals; and removing the single core from the cast crankshaft to leave the crankshaft with the hollow sections formed therein; wherein the hollow sections extending through the at least one of the plurality of pin bearing journals is formed to extend completely through the at least one of the plurality of pin bearing journals, between a first axial side of the respective pin bearing journal and a second axial side of the respective pin bearing journal along a longitudinal axis of the crankshaft; and wherein the hollow sections extending through the at least one of the plurality of main bearing journals is formed to extend completely through the at least one of the plurality of main bearing journals, between a first axial side of the respective main bearing journal and a second axial side of the respective main bearing journal along the longitudinal axis of the crankshaft.