Abstract text

Power split drive (PSD) transmissions capable of energy recovery and suitable for use in automotive applications. Each PSD transmission includes a mechanical transmission system for mechanically transmitting mechanical power between a rotatable input shaft and a rotatable output shaft, and a hydraulic transmission system containing a fluid for hydraulically transmitting hydraulic power between the input shaft and the output shaft, and at least a third shaft operatively interconnected to one of the mechanical and hydraulic transmission systems. The hydraulic transmission system is operatively coupled by at least a first planetary gear train to the mechanical transmission system. According to the invention, the PSD further comprises means operatively associated with at least one of the mechanical and hydraulic transmission systems for storing and releasing energy within the PSD transmission, the energy storing and releasing means comprising a flywheel or an accumulator or a combination thereof.