Hydromechanical Variable Transmission

Up to 20% Savings


The HVT allows drive characteristics to be adjusted over the entire speed range, provides optimal handling and the highest possible throughput with maximum fuel savings.

How HVT works as a function of travel speed:

  • At low speeds the advantage of the first full hydrostatic drive range is used:
  • Switching to reverse with no additional clutch
  • Fast acceleration and braking
  • Sensitive, precise positioning ability
  • With increasing speeds, a larger portion of the engine power is transmitted through the parallel mechanical path.  This allows acceleration with no interruption in tractive force.
  • At maximum travel speed, the entire power transmission takes place through the mechanical branch, providing the highest efficiency.   Losses through a torque converter are eliminated.
  • The identical advantages apply for driving in reverse.

The illustration above shows a combustion engine driving the input shaft of the HVT.  The upper hydrostatic and lower mechanical path can be seen inside the HVT, which transmit power separately or in combination.  The power is then combined on the output side in a summation gear train and made available to the drive shaft.

Contact Dana Rexroth Transmission Systems for more information.

The idea of a power split transmission comes originally from tractor applications, whereas Dana Rexroth Transmission Systems has transferred this technology to additional application groups through modular design of the HVT.   These applications include: