Abstract: Machine and method for deep rolling fillets of split-pins of engine crankshafts. Each split-pin comprises neighboring and arcuately offset crank pins connected between counter weights and has a centralized splitter fence which receives side loads from the connecting rods. Annular fillets are formed between the pins and opposite sides of the splitter fence as well as between the fillets and their associated counter weights. Limbs of the fillets at the splitter fence that describe the overlap of the split-pins are deep rolled with a high load for improving yield strength while the remaining arcuate portions of the fillets are rolled at lower loads to improve strength without undue distortion of the fence. The overlap of pin to main journals can also be rolled with increased load for increased yield strength.

Abstract: Machine and method for deep rolling annular fillets of journals of metallic workpieces, such as the crank pins of an engine crankshaft in which the crankshaft is loaded into a center positioned turning lathe, and left and right hand banks of floating jaw units located on opposite sides of the lathe are moved from a first station in which crankshafts can be loaded on or unloaded from the lathe to a second station in which inboard jaw ends of the jaw units with fillet rolling tools aboard are operatively engaged under load with each of the pin fillets, which are then simultaneously rolled as the lathe motor turns the crankshaft about its rotational axis and the tooling carried by the floating jaw units orbits the axis and completely deep rolls the fillets.

Abstract: Arcuately offset pairs of juxtapositioned pin journals of an internal combustion engine crankshaft have their fillets pressure rolled for fatigue strengthening by opposing inclined rollers carried in cages at the lower ends of a pair of relatively rotatable tool housings supported in a side-by-side relationship by a pair of jaws of floating clamping structure. This structure allows the rollers to follow the crank pin journals as the crankshaft is being turned so that arcuately offset crank pin fillets can be simultaneously pressure worked and strengthened. Opposing roller reaction loads are cancelled at load receiving bearings operatively interposed between the pair of tool housings.