Power unit for city vehicle - with interlocked infinitely variable transmission and torque control for optimum power and emission control

摘要

The engine (VKM) of the city vehicle is coupled to a roque converter (LVE) by a clutch (K) to drive two hydraulic pumps (HMG 1 & 2) which drive the two hydraulic motors (FM 1 & 2) via a torque control (HVG). The gear ratio of the transmission is controlled in an infinite manner by the torque control to provide optimum engine speed w.r.t. torque demands, in order to provide maximum efficiency and minimum exhaust emission. A hydraulic pressure store (HSp) is used to store energy from regenerative braking in order to boost the starting torque of the vehicle.