摘要 |
A hydro-mechanical transmission system or electro-mechanical transmission system is described which uses pumps/motors or generators/motors having smaller capacity than those employed in the conventional techniques, irrespective of setting of a mode switching point that is a basis for shifting between an input split mode and a compound split mode. A sun gear 7 of a first planetary gear train 5 is connected to an input shaft 4; a carrier 9 of the first planetary gear train 5 is connected to a sun gear 11 of a second planetary gear train 6 and to a first pump/motor 16; a ring gear 10 of the first planetary gear train 5 is connected to a second pump/motor 20; and a ring gear 14 of the second planetary gear train 6 is connected to an output shaft 25. A first clutch 27 is provided for engaging and disengaging a carrier 13 of the second planetary gear train 6 and the ring gear 10 of the first planetary gear train 5 with and from each other, and a second clutch is provided for engaging and disengaging the carrier 13 of the second planetary gear train 6 and a fixed end 28 with and from each other. |