Abstract
KEYWORDS – gearshift, clutch, double-transition shift, gearbox, transmission
ABSTRACT – Modern approaches in dynamic analysis of gearshifts are predominantly based on simple dynamical model. The shifting process is divided into phases and the differential dynamic equations are drawn on each phase. Due to the short gearshift period (0.2 – 0.5 sec) we proposed to apply the angular momentum conservation law for the dynamic analysis of the shifting processes. The gearbox is considered as closed mechanical system, and no external forces act on it. During the shift only internal forces acts on the gearbox members. Then, total angular momentum before and after the shift remains constant. Therefore with known moments of inertia of engine and transmission reduced to shafts and rotation velocities of the input and output shafts before shift we can calculate their rotation velocities after the shift. By the change of angular momentum, we can calculate the torque acting on the on-going clutch. The proposed method describes physical pattern of the gearshift process, universal (not depends on the type of the gearbox), significantly simplifies the calculations and assessment of torques acting on the clutches and gears. The approach can help solve the problem of controlling the process of double-transition shifts.