VarioDrive – the further development of the Vario transmission to an integral drive train
With the VarioDrive, Fendt has not only further developed the Vario transmission, but also developed a completely new drive train. Up to now, in a conventional transmission, the rear axle was supplied with torque in a fixed ratio, and when the four-wheel drive was engaged, also the front axle. With the new VarioDrive, the front axle can now be driven by a second, separate transmission output independent of the rear axle. The well-known Vario transmission has been expanded to become the VarioDrive drive train, which acts directly on both axles.
The drive unit on the VarioDrive works according to the principle of hydrostatic-mechanical power splitting. It has a hydraulic pump and two independent hydro motors, which supply the front and rear axles separately with drive torque. The hydro motor RA (rear axle) acts on the rear axle through hydrostatic-mechanical power splitting via planetary set and summation in the entire speed range. The hydro motor FA (front axle) is connected directly to the front axle and therefore mainly supplies high torque in the field. Through the intelligent overlay of the effective range from the drive to the front and rear axles, the maximum transmission output power is available over the entire speed range from 0 to 60 km/h without interruption of pulling power (range selector). Thanks to the intelligent transmission design, the hydro motor FA no longer transfers torque to the front axle above approx. 25 km/h; it is completely decoupled at higher speeds. There are no drag losses, which contributes significantly to an increase in efficiency when driving on the road.