Gear transmission having multiple input axles and transmission device using the same

PURPOSE: A gearshift train and a transmission using the same are provided to improve ride quality by strongly softly transferring shift torque. CONSTITUTION: A planetary(10) rotates three rotary shafts with a same shaft as the center. A motor and generator(MG) is connected to a rotary shaft of a sun gear of the planetary. A freedom degree control unit(20) controls the degree of freedom of the planetary by selectively synchronizing the rotation of two rotary shafts among the three rotary shafts. A gearshift train(100) is arranged between the planetary and a wheel driving shaft of a vehicle. The gearshift train comprises a rotary shaft which is connected to a rotary shaft of a ring gear.