Antriebseinheit

摘要

A power unit for a vehicle has an engine (10) coupled to a multi ratio gear box (13). The fuel supply to the engine is controlled by a fuel control system (11) and the selected ratio of the gear box is determined by a ratio selection control system (15A). The unit includes maps (19) in which is stored pre-recorded data relative to engine fuel consumption and exhaust emissions. For a given vehicle speed the data in the maps is read out, and combined using weighting factors to determine the merit figure. The merit figures for the different possible gear ratios are compared and the ratio which gives the highest merit figures is selected.