Viscomatic - A four-wheel-drive-system of the 3rd generation

In the course of a research project at Steyr-Daimler-Puch Fahrzeugtechnik Ges.m.b.H the external controllability of a viscous unit was investigated. Together with bench tests a mule vehicle was built up and microprocessor logic for automatic control was developed. The concept of the Viscomatic as a combination of a planetary gear set and a controlled viscous unit with stationary housing proved itself successfully. The available torque range of approximately 20:1 (stiff to soft) permits the best traction and ensures, together with a short response time, braking stability. Handling of the mule vehicle, as far as it is influenced by torque distribution, can be varied in a wide range when the stiffness of the viscous unit is selected manually. With an automatic setting, the reaction of the vehicle is always defined and easy to control. The Viscomatic can be applied to any power train configuration. Some examples are given.