Zf Friedrichshafen Ag

Other

Markus Henneken

Franz-Josef Schuler

Friedemann Jauch

Thomas Mauz

Kai-Uwe Herbster

Michael Kiefer

Wolfgang Schmid

Marko Poljansek

Thilo Schmidt

Bernd Allgaier

Hansj&ouml;rg Rosi

Gary O'Connor

A method for operating a drivetrain of a motor vehicle including a hybrid drive with a combustion engine and an electric motor. A transmission is arranged between the hybrid drive and a drive output and a clutch is arranged between the combustion engine and the electric motor so that, if a failure occurs in the drivetrain, especially in a transmission control device of the transmission, a gear corresponding to an emergency gear is engaged or remains engaged in the transmission. When the emergency gear is engaged, the motor vehicle is in motion and the engine speed falls below a defined value, the clutch arranged between the combustion engine and the electric motor disengages.

Method for operating a drivetrain

In the method for kick-down switching speed optimization in a motor vehicle with an automatic transmission, the kick-down upshift point is determined as a function of the load conditions and the road inclination in each case.

Kick-down switching speed optimization for an automatic transmission of a motor vehicle

A method for modifying a defined adaptive driving strategy, which is stored in the control system for an automatic transmission of a motor vehicle, for adaptation to another type of driver with a different driving style, consists in that the parameters used for the driving strategy are modified by the other driver, the data for this being input to the transmission electronics via an input unit and an interface with the electronics.

Method for modifying a defined adaptive driving strategy

A method is described for operating an automatic transmission in which a command for changing a current ratio of the automatic transmission is generated when achieving preset operating states of the vehicle automatically or by manual input in a manual shifting mode, the activated manual shifting mode being preferred to an automatic shifting mode. The manual shifting mode is quit when a current vehicle speed is less than a threshold value, or when a longitudinal acceleration of the vehicle is within a defined range, a lateral acceleration is less than a threshold value and a driver type evaluation counter is less than a limiting value.

Method for operating an automatic gearbox on a motor vehicle

A shift device for an automatic transmission of a vehicle, particularly of a motor vehicle, is proposed in which the request to change the current ratio of the automatic transmission upon reaching preset operating states of the vehicle can be automatically generated or by manual input in a manual shifting mode. A pulse counter is here provided by way of successive pulses and manual input can be functionally interlinked wherein a shift signal can be generated depending on the linkage.

Shift device for an automatic transmission of a vehicle

The method for testing the function of an electrohydraulically controlled automatic transmission upon a testing stand by simulation of a vehicle operation provides that the output shaft of the transmission be connected with a stationary torque-measuring hub and be blocked thereby; the shifting elements existing in the transmission are tested when the output shaft is blocked with an input rotational speed which is precisely sufficient to supply with hydraulic pressure the pressure setting members for the shifting elements. As characteristic quantity can be used the setting member current at which the shifting element slips or at which the slip tends toward zero when the shifting element closes.

Method for testing the function of an electrohydraulically controlled automatic transmission

A method for controlling an automatic transmission of a motor vehicle in the event of a spontaneous gas/pedal release (FastOff). The automatic transmission is driven by an internal combustion engine which can be influenced by an accelerator pedal and a signal proportional to a pedal position is fed to an electronic transmission control in which shifting characteristic field is stored and the spontaneous gas/pedal release (FastOff) is detected and an upshift block (FFO=1) is activated when a pedal position gradient (PSTG) falls below a pedal gradient threshold (KF_PSTG). The mode of the upshift block (FFO=1) is removed when a traction operation is detected when an actual engine torque (MMM) exceeds a push-pull line (KL_ZS) stored as a function of a value equivalent to an engine rotational speed (NMO) in dependence on a vehicle acceleration/deceleration (AIST) dependent on an overall tractional resistance (GFW) and pedal gradient thresholds (KW_PSTGPOS, KW_PSTGNEG).

Method for controlling an automatic gearbox of a motor vehicle in the event that the gas/pedal is spontaneously released

A method for control of an automatic transmission for a motor vehicle equipped with cruise control consists in that during cruise control of the transmission control changes to a separate driving program which is function of external influences, especially of the road inclination. This driving program is updated according to external influences. In the &ldquo;set&rdquo; state, change is made to the separate driving program and in the &ldquo;restore&rdquo; state the control can be adjusted so that the separate driving program be activated immediately or not until reaching the &ldquo;set&rdquo; control state.

Method for controlling an automatic transmission for a motor vehicle

The invention relates to a method for control of an automatic transmission of a motor vehicle wherein an electronic transmission control, by means of signals proportional to wheel speeds (NRA , NRA ), determines a transverse acceleration value (AQ) for outputting to additional program modules. The determined wheel speeds (NRA , NRA ) which enter in the transversal acceleration value (AQ) are corrected by vehicle wheels in a tolerance balance module of the wheels (M ) when a dynamic tire radius (RDYN) in one of the vehicle wheels diverges from a tire radius given in an optimum tire geometry.

Method for controlling an automatic gearbox involving determination of a transverse acceleration value

Within the scope of the method for acceleration of the torque breakdown of clutches in automatic transmissions, the follow-up of the hydraulic pressure and therewith the torque breakdown are accelerated by an over-compensation in the control.

Method to accelerate torque transmitting conditions within a clutch

A method for controlling an electronically controlled automatic transmission wherein the spontaneous gas/pedal release (FastOff) is detected and an upshift prevention system is activated when a pedal position gradient (PSTG) is lower than a pedal position gradient threshold (KF_PSTG); the state of the upshift prevention system (FFO&equals;1) is active until a) a traction operation is detected when the actual pedal position value (PST) exceeds a traction-thrust characteristic line (KF_ZS) and of an acceleration potential value (FBN) equivalent to a road gradient value; and/or b) a time (T , T ) has elapsed after a defined time period (THSV , THSV ) wherein the state of the upshift prevention system (FFO&equals;1) is abandoned.

Method for controlling the automatic gearbox of a motor vehicle during spontaneous release of the accelerator pedal

The invention relates to an urban driving operating method for an electronically controlled automatic transmission in which a driving speed characteristic (vf) is determined and it is possible to recognize an urban driving state when the driving speed characteristic (vf) is within a presettable value range with an upper limit and in which in addition a driving activity characteristic (FCOUNTER) is continuously determined. It is proposed according to the invention that the urban driving state be recognized when the driving activity characteristic (FCOUNTER) is also within a presettable value range with an upper limit and that a drive program optimized for the urban driving state be accessed.

Urban driving operating method for an electronically controlled automatic gearbox

In a method for controlling an automatic transmission of a motor vehicle having an electronic gear control (EGS) that continuously exchanges signals with a vehicle dynamics regulator (FDR), the electronic gear control (EGS) receives signals (SL) of an anti-slip control system (ASC) and/or of an anti-blocking system (ABS). In addition the vehicle dynamics regulator (FDR) is functionally linked with a dynamic stabilizer (DS) which in predefined operating situations issues a signal (SV) to the electronic gear control (EGS) via the vehicle dynamics control (FDR), which signal is processed simultaneously with the incoming signals (SL) from the anti-slip control system (ASC) and/or the anti-blocking system (ABS).

Method for controlling the automatic gearbox of a motor vehicle

The invention relates to a method for controlling an automatic transmission wherein several shift programs are provided and allocated to specific values of a driving activity characteristic (FAKG) and in each shift program shifting characteristic lines and shifting rotational speeds are determined by accelerator pedal positions. The shifting rotational speeds are immediately increased to higher rotational speeds when the driver quickly depresses the accelerator pedal causing the accelerator pedal position gradient to exceed a presettable limit value. According to the invention, it is proposed that the shifting rotational speeds be determined according to the actual value of the driving activity characteristic by interpolation between shifting characteristic lines from two respective adjacent shift programs and the driving activity characteristic be immediately increased by a presettable offset amount when the accelerator pedal position gradient exceeds the presettable limit value.

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Kressbronn, Germany

Markus Henneken