Zf Friedrichshafen Ag

Zahnradfabrik Friedrichshafen, Ag.

Jürgen Legner

Wolfgang Rebholz

Stephan Schinacher

Marcus Hiemer

Helmut Eymuller

Egon Mann

Eduard Heilig

Sven Bieber

Rico Glöckner

Migen Bebeti

Jan-Frederik Kuhn

Siegfried Stützle

Roland Fischer

Martin Haffner

Gerhard Buck

Klaus Baumann

Matthias Madlener

Hugo Burkhart

Stefan Traub

Michael Riedhammer

Robert Morrison

Michael Siber

Torsten Berg

Jörg Geis

Michael Herlitzek

Helmut Eymüller

Jochen Schneider

Kazutaka Iuchi

Werner Denk

Raphael Zohner

Andreas Rothmund

Michael Thielmann

A method for operating an electrified drive train including a drive motor, inverter, and accelerator pedal. The drive motor provides a motor speed and torque according to a position of the accelerator pedal. The inverter detects a motor mode when a motor torque greater than a threshold motor torque is provided. The inverter detects a generator mode when a generator torque greater than a threshold generator torque is provided. The inverter detects a torque-free state of the drive motor when the generator torque is less than the threshold generator torque and the motor torque is less than the threshold motor torque. Each position of the accelerator pedal is assigned a respective maximum motor speed, and a motor fault is detected when a motor speed above an assigned speed is detected and, at the same time, a motor mode of the drive motor is detected.

Method for operating an electrified drive train for a working machine, electrified drive train for a working machine and working machine

A method of controlling an electric drivetrain of a work machine, the method including determining whether a brake pedal actuation has occurred with an actuation distance greater than an actuation distance threshold value for an actuation duration longer than an actuation duration threshold value. The method further includes determining whether no drive torque maintaining condition exists, based on a determination that the brake pedal actuation occurred with the actuation distance greater than the actuation distance threshold value for the actuation duration longer than the actuation duration threshold value. The method further includes generating a control signal for the electric drivetrain to disable a torque generation by the electric drivetrain based on a determination that no drive torque maintaining condition exists.

Method for controlling an electric drivetrain of a work machine, and corresponding control device

The disclosure relates to a method for controlling a flow of electrical power between an electrical energy source and at least two electric machines of a working vehicle. In one step, an electrical power which can be drawn from the energy source is determined. In a further step, at least two electrical powers which are required for the at least two electric machines are determined. In yet another step, the electrical power which can be drawn is distributed to the at least two electric machines in the ratio of the at least two required electrical powers, such a distribution being carried out if the sum of the at least two required electrical powers is greater than the electrical power which can be drawn. The disclosure also relates to a controller for carrying out the described method and to a working vehicle having such a controller.

Method and controller for controlling the flow of electrical power in a working vehicle

The disclosure relates to a method for operating a drive train of a working machine, wherein the drive train comprises a working drive and a travel drive. The working drive is driven by a first electric motor and the travel drive is driven by a second electric motor. The disclosed method includes that the travel drive is additionally driven by the first electric motor if at least one performance criterion of said travel drive has been met. The disclosure further relates to a corresponding drive train and to a working machine.

Method for operating a drive train of a working machine, drive train for a working machine, and working machine

A method for operating a drive train of a working machine, wherein a traction drive of the drive train is driven by an electric traction motor via a transmission and wherein, when a gear stage of the transmission is changed, a rotational speed of the traction motor is synchronised with the gear stage being engaged. The method further includes a computational model of the traction motor that is used for the rotational speed synchronisation. The model, taking into account a moment of inertia of the traction motor, describes a torque to be delivered for the rotational speed synchronisation. A corresponding drive train and a working machine is also disclosed.

Method for operating a drive train for a working machine, drive train for a working machine, and working machine

A process for determining a setpoint rotational speed of a work machine engine, having a continuously variable transmission, based on operation of power hydraulics. The setpoint rotational speed for highly productive operation is determined, without knowledge current operation of the power hydraulics, by a basic engine speed setting. With knowledge of the current operating state, the setpoint rotational speed is determined by the basic speed settings and low or high engine speed settings. The low speed setting alone determines setpoint rotational speeds that are lower than the basic speed setting or a combination of the low and basic speed settings. The high speed setting alone determines setpoint rotational speeds that are higher than the basic speed setting or a combination of the basic and high speed settings. The speed settings can comprise a setpoint rotational speed range of above a reciprocal transmission range of the variable transmission.

Method for ascertaining the target rotational speed of a drive machine of a work machine comprising a continuously variable transmission and a working hydraulic system

A traction force limiting device for a working machine with a continuously variable transmission that comprises a variator for adjusting the rotational speed ratio of the transmission independently of the torque ratio of the transmission. The traction force limiting device has a traction force interface for providing information to determine a traction force of the working machine, a limit value interface for setting a traction force limit value of the working machine and a control interface for emitting a control signal to the variator. Additionally, the traction force limiting device has a computer unit designed, on a basis of information provided via the traction force interface, to determine the traction force, to compare the traction force determined with the traction force limit value set via the limit value interface, and to control the variator in such manner that the traction force does not exceed the traction force limit value.

Tensile force-limiting device for a working machine

A drive-train has an internal combustion engine () with an exhaust gas turbocharger, which drives a vehicle wheel () by way of a power-branching transmission (). When there is an increase of the power demanded from the combustion engine () but the exhaust gas turbocharger is not yet producing the required charging pressure, an additional motor () is always switched into the drive-train in order to deliver torque to the drive-train.

Drive train of a mobile vehicle

A device for controlling a gear ratio of a hydrostatic mechanical power-split transmission comprises an input switch () which, when rotated, produces a particular transmission characteristic and, at the same time, limits the maximum pressure. The selected position of the input switch () selects a particular maximum pressure curve from a large number of stored maximum pressure curves.

Control device for an infinite hydrostatic mechanical power split transmission

A method for the operation of a vehicle drive-train of a working machine having a drive motor, a transmission whose transmission ratio can be varied continuously, and a drive output. A rotational speed (nmot) of the drive motor can be varied by the driver, by the driver's actuation of a first control element (), within a rotational speed range () delimited by an upper characteristic line (nmoto) and a lower characteristic line (nmotu). The characteristic lines (nmoto, nmotu) are functions of a reciprocal transmission ratio (irez) of the transmission. Furthermore, the rotational speed (nmot) of the drive motor that can be set by the driver by way of the first control element (), can be influenced by the driver's actuation of a second control element () and as a function of an operating condition of the working machine.

Operating method for a vehicle drive train of a working machine including a drive motor, a transmission and an output

With a torque-controlled internal combustion engine and a variable-speed transmission having fixed shift gear ratios, during a shift, the internal combustion engine is controlled in such manner that the drive output torque of the transmission remains the same before and after the shift.

Method for operating a drive train for a mobile vehicle

A transmission device () with secondarily coupled power splitting in which part of an applied torque can be conducted, in a first power branch () at least by way of a hydrostatic system (), and the other part of the torque can be conducted in a second power branch () via mechanical system (), located between a transmission input () and a transmission output (). The hydrostatic system () of the first power branch () includes at least one pump () and at least one motor () that is functionally connected to the pump by way of a hydraulic circuit, and both of the pump and motor are adjustable. The two power paths () can be summed by a summing gear system (). The pump () is made smaller than the motor ().

Gearing device with secondarily coupled power split

A vehicle has a drive train comprising a drive unit, a hydrostatic-mechanical power-split gear unit operatively connected to the drive unit and an output, and at least one braking device. An additional actuating device is allocated to the braking device and is operatively connected with a power request element and/or a driving direction selection element. Upon the presence of a deceleration of the vehicle requested by the driver through the power request element and/or the driving direction selection element and, the braking device is actuated to an extent that initiates a braking torque in the drive train. Upon the presence of a requested deceleration of the vehicle, a driving torque on the side of the drive unit is provided in the area of the output for a braking device that is not actuated by the driver. If the rotational speed of the drive unit exceeds a defined threshold of rotational speed, the braking device is operated to an extent that initiates a braking torque in the drive train.

Vehicle and method for operating a vehicle

A device for varying the stroke of first and second hydraulic machines. At least one piston is functionally connected to axes of the hydraulic machines. Depending on power demanded by a driver, the piston can be acted upon, via position and high pressure control valve units of a valve system, with pressures that correspond to a pressure present in the hydraulic machines and that act in a first adjustment direction of the hydraulic machines axes. Pressure in the hydraulic machines is controlled by the position control valve unit and is limited by the high pressure control valve unit. The piston can be acted upon by the valve system with pressures that correspond to the pressure present in the hydraulic machines and that act in a second adjustment direction of the axes of the hydraulic machines, and action of the position control valve unit can be reversed.

Device for varying the swept volumes of a first hydraulic machine and a second hydraulic machine

A device for adjusting the swept volume of a first piston machine (), of transverse axis design, and a second piston machine (), of transverse axis design. The device including a common component (), via which the swept volumes can be adjusted, and a valve () which, when a maximum pressure level in the working lines () is exceeded, can be rerouted in such a way that the common component () reroutes the swept volume in a direction toward the lower power input.

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Friedrichshafen, Germany

Jürgen Legner