Patent ID: 6250171
Filing Date: 2001-06-26
Classification: F16H,Y10T

Abstract:
A variable-ratio gear transmission, in which an input shaft is connected to an output shaft by two partial transmissions having, in each case, an intermediate shaft, and the intermediate shafts, arranged concentrically with respect to each other, are connected, on the one hand, to the input shaft by a respective frictionally engaged powershift clutch that can be engaged and disengaged, and, on the other hand, to a common countershaft by assigned gear stages for the formation of the gear ratio, in each case, of one gear, the countershaft being connected to the output shaft by a permanently effective gear constant, and in which the gear stage of gear I is assigned to the first partial transmission, whereas the gear stage of gear II and an auxiliary gear stage are assigned to the second partial transmission, and the gear ratio of the auxiliary gear stage of the second partial transmission is equal to the gear ratio of a gear stage of the first partial transmission, and in which the idler of the auxiliary gear stage is arranged so as to be coaxial and rotatable with respect to the intermediate shafts and is able to be coupled to the associated intermediate shaft of the second partial transmission by a first gear-type clutch, and in which the idler of that gear stage of the first partial transmission whose gear ratio is equal to the gear ratio of the auxiliary gear stage of the second partial transmission can be connected by a second gear-type clutch to the associated intermediate shaft of the first partial transmission, comprising:a single gear stage (ZIII*/III), whose idler, arranged so as to be coaxial and rotatable with respect to the intermediate shafts (14, 15), is connected both to the first gear-type clutch (s-III*/IV*) as well as to the second gear-type clutch (s-III), to provide the auxiliary gear stage (ZIII*) of the second partial transmission (13) with the same gear ratio as the gear stage (ZIII)of the first partial transmission (12).