The basic function principle
Via an operating fluid, the pump wheel driven by the motor transmits power wear-free to the turbine wheel which, in turn, drives the driven machine.

Wear-free power transmission In Compact design
Voith Turbo hydronamic couplings combine, in the smallest of spaces,a circular pump (pump wheel) and a turbine (turbine whell) which drives a driven machine. Torque emitted from the motor is converted into flow energy as mechanical energy The driven machine.


Continously variable between “completely full” and “completely empty”
By changing the fill level in the working circuit, the transmission of torque, and consequently the operating speed of the driven machine, is adjusted smoothly and steplessly: the filling medium flows freely into the coupling's catching ring, and then into the working circuit by centrifugal force. The fluid between the pump and turbine wheels trans­mits torque via hydrodynamic action. To allow for filling control and heat dissipation, the fluid exits the working circuit via nozzles into a rotating pump shell. There, it is taken up by a dynamic pressure pump, which points into rotating fluid ring and, via the cooler, redirected back to the collecting ring. Two solenoid valves control (entirely without external moving parts) the active fluid volume in the working circuit between "completely full" and "completely empty" by adding or removing fluid from the couplings working circuit.

Smooth start-up
The smoother a machine accelerates, the more it is protected. This is especially important for the belt itself, typically the most expensive component in the system. To enable this, an electronic control processes the values of motor power and belt speed. Correspondingly, it actuates the fill and drain valve to achieve controlled acceleration of the conveyor, minimizing the tensile forces in the belt during start-up. Parameters for acceleration periods of up to several minutes can be set.

Advantages which impress

  • Wear-free transmission of power
  • Smooth build-up of break-away torque
  • Controlled acceleration of heaviest masses
  • Overload protection in the event of a blockage
  • Damping of torsional vibrations and jolts
  • Variable speed adjustment of the driven machine
  • Clutching and declutching of driven machine while motor is running
  • High efficiency at nominal operation owing to low slip
  • Load-free motor start-up; therefore possibility of frequent starts, even with motors with lower service factors
  • In the case of multi-motor drives, the electric grid is protected owing to sequential starts of individual motors
  • Available in specific designs for water as the operating medium Insensitive to extreme ambient conditions such as dust, heat and cold
  • Robust design with long service life and high availability
  • Available in explosion-proof design