HYDRAULIC HYBRID POWERTRAIN

摘要

A hydraulic hybrid powertrain for a vehicle is disclosed. The powertrain has an internal combustion engine selectively drivingly engaged with an input of a stepped-ratio transmission through a torque converter and through a speed direction changing device. An output of the stepped-ratio transmission is selectively drivingly engaged with a vehicle output. An intermediate gear set is drivingly engaged with the speed direction changing device and drivingly engaged with the input of the stepped-ratio transmission. A hydraulic machine in fluid communication with a hydraulic accumulator assembly, a transmission shaft of the hydraulic machine being drivingly engaged or selectively drivingly engaged with the intermediate gear set for providing energy to the intermediate gear set and for absorbing energy from the intermediate gear set. Also disclosed are methods of operating the hydraulic hybrid powertrain.