Transmission for a hydraulic hybrid vehicle, comprising a planetary gear train linked to a pump by a speed reducer

摘要

A transmission for a hydraulic hybrid motor vehicle includes a planetary gear train (30) capable of differential operation. The planetary gear train has a first element (32) linked to an internal combustion engine (34), a second element (40) linked to drive wheels (22) of the vehicle, and a third element (36) linked to a hydraulic pump (64). The transmission (1) further includes a hydraulic machine which drives the drive wheels (22) by way of a link between the third element (36) of the planetary gear train (30) and the hydraulic pump (64). This link includes a speed reducer (38, 60) that provides, when the whole of the planetary gear train is rotating at the same speed, a reduction in the speed of rotation of the pump relative to that of the internal combustion engine (34) that is greater than a value of approximately two.