Zf Friedrichshafen Ag

Markus Terwart

Rainer Novak

Martin-Joachim Bader

Karl Locher

Alexander Hoffmann

Lukas Spath

Olaf Moseler

Tobias Pfleger

Mario Bühner

Andreas Feiner

Dirk Friederich

Andreas Roedler

Dietmar Zuber

Moghtader Salehan

Robert Weissenrieder

Matthias Reisch

Erwin Wack

Thomas Dögel

Andreas Orlamünder

Thomas John

Daniel Lorenz

Kyrill Siemens

Tobias Dieckhoff

Eduard Steiner

Robert Gronner

Matthias Arzner

Thomas Rauber

Frank Riever

Michael Vollmann

Frank Veth

Andreas Fischer

Gerald Suckfüll

A method for operating a hydraulic actuator for a prime mover or a drive device of a vehicle includes determining that the hydraulic actuator is to be actuated via an actuating system and detecting an operating variable influenced by a filling state of the hydraulic actuator indicative of pressure conditions in the hydraulic actuator, with the operating variable being separate from actuator operating variables of the hydraulic actuator and the actuating system. The method further includes pressurizing the actuator during a fast fill phase to one or more pressures over a fast fill time period in response to determining that the hydraulic actuator is to be actuated. The fast fill time period and the one or more pressures are adjusted as a function of the operating variable under certain operating conditions. Additionally, the method includes pressurizing the actuator during a pressure build-up phase after the fast fill phase.

Method for operating a hydraulic actuator

A method for adapting a biting point pressure of a hydraulically actuated hybrid disengaging clutch arranged in a hybrid drive train of a motor vehicle between an internal combustion engine and an electric machine includes step by step implementation during driving of the motor vehicle via a plurality of selected engagement operations of the hybrid disengaging clutch with a manipulation of a rapid filling routine. Proceeding from an initially stored biting point pressure, a setting pressure, which is reduced relative to a subsequent rapid filling routine, is incrementally increased step by step. An actual value, which is set in each case for a test parameter, is detected until the actual value corresponds to a setpoint value. A change in the transmission of torque of the hybrid disengaging clutch is derivable via the actual value.

Method for adapting a biting point of a hydraulically actuated hybrid disengaging clutch

A method for adapting a biting point filling time of a hydraulically actuated hybrid disengaging clutch is implemented step by step during driving of the motor vehicle via a plurality of selected engagement phases of the hybrid disengaging clutch with a manipulation of the customary rapid filling routine. Proceeding from an initially stored biting point filling time, a filling time which is shortened in comparison with this for a subsequent rapid filling routine is increased step by step, in each case by an increment. Here, an actual value which is set in each case for a test parameter, from which a change in the transmission of torque of the hybrid disengaging clutch can be derived, is detected until the actual value corresponds to a setpoint value.

Method for adapting a biting point filling time of a hydraulically actuated hybrid disengaging clutch

A method for actuating a hydraulic system of a transmission comprising a variable displacement hydraulic pump and a pilot-controllable system pressure valve, the method including, in order to determine a pump characteristic curve of the hydraulic pump, initially transferring the hydraulic system into a defined operating condition range in which the volumetric output flow, routed via the system pressure valve and applied at the system pressure valve by the hydraulic pump, is greater or less than a hydraulic fluid flow out of the hydraulic system. The method further includes pilot-controlling the system pressure valve to set a defined pressure level of the system pressure. The method additionally includes reducing or increasing the volumetric output flow while monitoring the system pressure, and determining a volumetric output flow corresponding to the hydraulic fluid flow of the hydraulic system with a certain deviation of a current system pressure from the defined system pressure.

Method for actuating a hydraulic system of a transmission having a variable displacement hydraulic pump

A method for operating a parking lock device () with a hydraulic system (), the method including, when there is a demand to engage the parking lock device () originating from a disengaged operating condition of the parking lock device (), applying a pilot pressure (p_EDS) at the parking lock valve (PSV) and applying the main pressure (p_sys) at the parking lock valve (PSV), if necessary, via the positioning valve (POSV). The pilot pressure (p_EDS) and the main pressure (p_sys) are each guided to defined pressure levels at which the parking lock valve (PSV) is transferrable into the further operating condition range of the parking lock valve (PSV) by the active actuating force against the pilot pressure (p_EDS) and against the pressure between the parking lock valve (PSV) and the parking lock cylinder ().

Method for operating a parking lock device by means of a hydraulic system

A hydraulic system of a transmission includes a plurality of pressure control valves. A pilot force component and an actuating force component of additional pressure control valves are applicable in the direction of a first end position of a valve slide. A downstream pressure of the additional pressure control valves is applicable in the direction of a second end position of the valve slide. Clutch valves are configured to be brought into operative connection by a pilot-controlled valve unit with an area guiding pressure of a primary pressure circuit or with an additional valve unit. The additional valve unit is a pressure-limiting valve with a predefined pressure level adjusted upstream of the additional valve unit and connected downstream to a low-pressure area.

Hydraulic system of a transmission with a multiple number of pressure control valves

A method for operating a parking lock device with a hydraulic system, the method including applying the pressure between the parking lock valve and the pressure chamber at the parking lock valve against the actuating force. Moreover, when there is a demand to disengage the parking lock device, the method includes applying the pilot pressure at the parking lock valve against the actuating force when the pressure between the parking lock valve and the pressure chamber of the parking lock valve is less than a threshold value at which the parking lock valve is transferred into a further operating condition range. Additionally, when there is a demand to disengage the parking lock device, the method includes adjusting the pilot pressure applied at the positioning valve to a pressure level at which the positioning valve is transferred into or held in its defined operating condition range.

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 torsional vibration damping arrangement for a drivetrain of a vehicle comprises a rotational mass arrangement which is rotatable around a rotational axis A and a damping arrangement fixed with respect to rotation relative to the rotational axis A. A displacer unit is operatively connected to the primary inertia element on the one side and to the secondary inertia element on the other side. The damping arrangement includes a slave cylinder with a working chamber having a volume V2, and the working chamber of the slave cylinder is operatively connected to the working chamber of the displacer unit. The damping arrangement includes a stiffness arrangement and a damper mass, and the slave cylinder of the damping arrangement is operatively connected to the damper mass by a stiffness arrangement.

Torsional vibration damping assembly for a drive train of a vehicle

A method for operating a dual-clutch transmission with two clutches. During realization of a ratio, a first clutch is closed and a second clutch is open. During a ratio change, the first clutch is opened and the second clutch is closed. During a ratio change within short operating times, a target actuating pressure of the clutch for engagement is set to a fast-charging pressure level and subsequently adjusted to a closing pressure level, while a target actuating pressure of the clutch for disengagement is adjusted to an opening pressure level before setting the closing pressure level of the clutch for engagement. At least during a ratio change, an actual actuating pressure of the clutch for engagement is monitored and the target actuating pressure of the clutch for disengagement is adjusted to the opening pressure level if the actual actuating pressure of the clutch for engagement exceeds a pressure threshold.

Control method for a dual-clutch transmission

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.

Control method for a transmission with hydraulic system comprising a variable displacement pump

A method for determining a conveying capacity of a hydraulic pump includes opening a blockable flow cross-section in order to connect a pressure side of the hydraulic pump to an area of the hydraulic system through the flow cross-section after operating the hydraulic pump driven at a defined rotational speed. The flow cross-section is configured with the hydraulic pump such that an entire conveying volume flow provided by the hydraulic pump is guided through the flow cross-section when the flow cross-section is open. The method further includes comparing a change to an operating state of the transmission resulting from opening of the flow cross-section to a reference change to the operating state and determining the conveying capacity of the hydraulic pump as a function of a deviation between the change to the operating state and the reference change to the operating state.

Flow output determination method for a hydraulic pump in a transmission hydraulic system

A method for controlling a hydraulic fluid supply system of an automatic transmission of a motor vehicle includes supplying the hydraulic fluid supply system with hydraulic fluid from at least one of a hydraulic pump controlled on an engine side and a hydraulic pump controlled on a gear set side. The method also includes controlling a cooling valve of the hydraulic fluid supply system as a function of detected motor vehicle parameters in order to set an adjusted power distribution with the hydraulic pump controlled on the engine side and the hydraulic pump controlled on the gear set side.

Method for controlling a hydraulic-medium supply system of an automatic transmission

A method for controlling a hydraulic fluid supply system of an automatic transmission of a motor vehicle includes supplying the hydraulic fluid supply system with hydraulic fluid from at least one of a hydraulic pump controlled on an engine side and a hydraulic pump controlled on a gear set side. The method also includes controlling a retaining valve of the hydraulic fluid supply system as a function of detected motor vehicle parameters in order to set an adjusted power distribution with the hydraulic pump controlled on the engine side and the hydraulic pump controlled on the gear set side.

Method for actuating a hydraulic medium supply system of an automatic transmission

A method of operating a clutch serving as a shift element and/or starting clutch of a drive train. During engagement, the clutch will be filled by a fast filling up to a defined minimum pressure. The fast filling is at least subdivided into two phases comprising a basic filling phase and an extension and/or a cutout phase. At the end of the basic filling phase, the actual clutch pressure is measured, and then, when the actual clutch pressure is equal to or larger than the minimum pressure, the extension and/or cutout phase is activated immediately following the basic filling phase. When the actual clutch pressure is lower than the minimum pressure, activation of the extension and/or the cutout phase is at least delayed by a pressure holding phase and, if necessary, by a pressure surplus phase.

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Thundorf, Germany

Markus Terwart