Zf Friedrichshafen Ag

Dirk Friederich

Rainer Novak

Markus Terwart

Lukas Spath

A method for actuating a valve device as a function of a characteristic curve including actuating the valve device with a dither superimposed on a target value (i_EDS) with such a frequency that the operating condition of the valve device follows the actuation corresponding to the characteristic curve (v_kk). The method further includes determining, with the characteristic curve (v_kk), the output values ('1', x) which correlate with the target values (i_EDS) at inflection points of a harmonic oscillation impressed upon the valve device with the dither, and determining further output values as a function of the output values ('1', x). The amplitude of the dither is predefined such that, during an actuation of the valve device, one of the inflection points lies in a first or second characteristic curve range (v_kkor v_kk, v_kkor v_kk), and another inflection point lies in a third characteristic curve range (v_kkor v_kk).

Method for actuating a valve device on the basis of a characteristic curve

A method for operating a transmission () with a hydraulic system comprising a variable capacity hydraulic pump, the method comprising determining during operation, a current hydraulic fluid volume requirement for actuating the transmission () and for temperature controlling and lubricating components of the transmission (); setting the delivery volume of the hydraulic pump in a manner dependent on the currently determined hydraulic fluid volume requirement of the transmission (), the delivery volume of the hydraulic pump, provided for temperature controlling and lubricating the components, being guided at least partially through a heat exchanger; wherein the delivery volume of the hydraulic pump is varied in a manner dependent on a temperature of the hydraulic fluid to an extent which sets that part of the delivery volume flow of the hydraulic pump which is to be guided via the heat exchanger.

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Daisendorf, Germany

Dirk Friederich