Hydraulic Hybrid Powertrain

摘要

The invention relates to a hydraulic hybrid powertrain (200; 1200; 2200; 3200; 4200; 5200) for a vehicle, comprising: an internal combustion engine (204) selectively drivingly engaged with an input of a stepped-ratio transmission (210) through a torque converter (206) and through a speed direction changing device (208), an output of the stepped-ratio transmission (210) being selectively drivingly engaged with a vehicle output (212); an intermediate gear set (226) drivingly engaged with the speed direction changing device (208) and drivingly engaged with the input of the stepped-ratio transmission (210); and a hydraulic machine (214) in fluid communication with a hydraulic accumulator assembly, a transmission shaft of the hydraulic machine (214) being drivingly engaged or selectively drivingly engaged with the intermediate gear set (226) for providing energy to the intermediate gear set (226) and for absorbing energy from the intermediate gear set (226). The invention further relates to methods of operating the hydraulic hybrid powertrain.