Search results for " ingranaggi"

On the gear mechanics before the cycloid and involute profiling

2011

After the extraordinary development of the machinery in the Hellenistic antiquity, the gear technique was transmitted to the Middle Ages through the Byzantine and Islamic culture and then to the Modern Era. The tooth profile was very crude, often trapezoidal or even rectangular and the gear behavior differed substantially from the modern involute profile. The kinematics of trapezoid profiles is here analyzed in detail, focusing on the temporal variation of the speed ratio due to the back and forth shifting of the relative instant center. Considering an isolated tooth pair, an approach phase is firstly observable, where the tip of the driven profile is pushed by the driver flank and then, af…