PURPOSE: To eliminate the concentration of the strain (stress) of a tightening part by forming a tightening hole for the fixation onto a crankshaft and forming a tightening hole for the fixation onto the front cover of a torque converter onto a driving disc and press-molding the both tightening holes from the surface opposed to the installation surface with the crankshaft.
CONSTITUTION: A bolt hole 8 is formed for the integral connection of a driving disc body 1 and the front cover 6 of a torque converter, and a bolt hole 9 is formed for the integral connection of the driving disc body 1 and a crankshaft. When the bolt holes 8 and 9 and a fitting hole 10 on the crankshaft are punched out through the press-molding, said punching-out is carried out from the direction A shown by the arrow. When the driving disc body 1 is installed onto the crankshaft after the working for the disc 2, a thrust force due to installation is generated along the axis line O in the reverse direction to the direction A shown by the arrow. After the driving disc body 1 is installed onto the crankshaft, the strain of the disc 2 and the thrust force during the operation of the disc are offset each other.
KOBAYASHI TOSHIHIRO
MAEDA HIROAKI
SOGA YOSHITAKA
