Control and Operating Behavior of Continuously Variable Chain Transmissions

A new adaptive controller layout for chain converters for universal use in different applications and set-ups is being presented. Based on the control structure chosen for synchronization of the claw couplings of a chain converter type i2-transmission during range shifts, a universal control layout was developed. Both the conventional clamping system for the well known PIV1-based chain converter and a newly developed pressure controlled clamping system were taken into account. As the most important non-linearity the ratio of clamping forces between driving and driven pulley (ζ-value) for steady state operation was mapped in a characteristic diagram and is being adapted during normal operation. Besides improvements in performance and better availability of information for diagnostic purposes, an open loop control of the rate of ratio change becomes possible.