Patent ID: 7493203
Filing Date: 2009-02-17
Classification: F16H,Y10T

Abstract:
1. A method for regulating the transmission ratio of a power-branched automatic transmission that includes an input shaft drivable by an engine, a variator with a continuously variable transmission ratio, a gear transmission, an output shaft and at least two control clutches through which the variator and the gear transmission can be operatively connected, said method comprising the steps of: traversing a first portion of the overall transmission ratio range of the power-branched transmission within the transmission ratio range of the variator in a first transmission ratio change direction; traversing a second portion of the overall transmission ratio range of the power-branched transmission within the transmission ratio range of the variator in a second transmission ratio change direction that is opposite from the first transmission ratio change direction; at a transition point between the first and second variator transmission ratio change directions changing the sign of at least one regulator parameter of an adjustment regulator utilized to set the transmission ratio of the variator; and changing an output signal of the adjustment regulator in accordance with a momentary value of di ges /di var , whereby i ges is the overall transmission ratio of the power-branched transmission and i var is the transmission ratio of the variator.