SHAFT

摘要

A tubular shaft (24) has a portion of reduced inner diameter (52) at a location where joining to an apertured member (16) is desired. The aperture (18,22) in the member (16) is lobed with splines (49) in the lobes and has an undercut groove or grooves (51) and is hardened. The shaft (24) is inserted in the aperture (18,22) and the reduced inner diameter portion (52) is expanded to force the shaft material into the lobes (48) and groove (51) and around the splines (49) to form a connection which resists torque and axial separation. The tube expansion is effected by forcing a series of balls (58) through the reduced diameter portion (52), each ball (58) being slightly larger than the reduced diameter (52) and larger than the previous ball (58) but smaller than the remainder of the shaft internal diameter. A crankshaft (10) is assembled with this method wherein counterweights (16) have lobed apertures (18,22) to receive end portions (52) of crank pins (24) and main journals (12) having reduced internal diameters. Lubricating passages (96,98) are formed in crankshafts having main journals (12) and crank pins (24) with reduced end portions (52,57) defining planar shoulders (90) on their body portions (52,57) and annular grooves (92) on the shoulders (90), bores (108) in the counterweights (16) intersecting the annular grooves (92) on the adjacent shoulders (90), and passages (96,98) in each main journal (57) and crank pin (24) connecting its annular groove (92) with the surface thereof.