Patent ID: 8989970
Filing Date: 2015-03-24
Classification: F16H,G01P,Y10T

Abstract:
1. A continuously variable ratio transmission assembly (“variator”) comprising: a roller configured to transmit drive between a pair of races, the roller being movable in accordance with changes in a variator ratio, a hydraulic actuator configured to apply a biasing force to the roller, at least one valve connected to the actuator through a hydraulic line to control pressure applied to the actuator and so to control the biasing force, and an electronic control configured to determine the required biasing force and configured to set the at least one valve accordingly, wherein the electronic control is configured to determine a predicted rate of flow in the hydraulic line based at least on a variator ratio and a rate of change of the variator ratio, to determine a consequent pressure change between the actuator and the valve based at least on the variator ratio and the rate of change of the variator ratio, and to adjust the valve setting to compensate for the pressure change and damp oscillation of the roller.