Abstract: A method of actuating a form-locking shift element of a transmission. To shift from a current gear to a target gear, an actuation time is determined for the locking shift element to be engaged during a gear shift depending on a reaction time of the assemblies participating during actuation of the locking shift element, an engaging time of the locking shift element, and at least one filtered signal such that the locking shift element is engaged within a specified rotational speed window encompassing a specified differential rotational speed. It is verified whether the locking shift element can be engaged within the specified rotational speed window depending on at least one unfiltered signal, and, if the locking shift element can be engaged within the specified rotational speed window, the actuation is unaffected; conversely, if the locking shift element cannot be engaged within the specified rotational speed window, the actuation is affected.

Abstract: A method of operating a vehicle drive train having a drive machine, a transmission apparatus having a plurality of shift elements and an output drive. The plurality of shift elements are engaged or disengaged in a power flow for achieving different transmission ratios within the transmission apparatus. The output drive is coupled to a transmission output shaft and the drive machine is coupled to a transmission input shaft of the transmission apparatus. Upon a request to interrupt power flow within the transmission apparatus, between the transmission input shaft and the transmission output shaft, a maximum number of shift elements are transferred to and/or held in an engaged operating state, and the remaining portion of the shift elements are transferred to and/or held in a disengaged operating state with the transmission output shaft being rotatable.

Abstract: A method for shifting an automatic or an automated transmission of a motor vehicle to a “neutral” position such that the shift position of the transmission and a parking lock, provided for keeping the motor vehicle stationary, are engaged as a function of a shift position selected with a driver operated selector device and as a function of other operating parameters of the motor vehicle. A holding phase, in which the transmission is in the neutral position, free from friction force locking, can be activated by a separate operating device which is provided, in addition to the selector device, but only when the motor vehicle is simultaneously at least approximately stationary, an ignition current circuit that acts on a drive engine of the motor vehicle is electrically interrupted, and the “neutral” (N) shift position is specified by a selector device.

Abstract: A method of operating a transmission of a vehicle drive train with at least one drive machine. The transmission is formed with at least one interlocking shift element and a plurality of frictional shift elements in order to obtain various gear ratios. During an engaging process of the interlocking shift element, starting from a disengaged operating condition, in which halves of the interlocking shift element are out of engagement, to an engaged operating condition, in which the shift element halves are interlocked in a rotationally fixed manner, when interlock between the shift element halves is obstructed, a rotational speed difference is produced at least temporarily between the shift element halves, at which the interlock in the area of the interlocking shift element can be engaged. To produce the speed difference between the shift element halves, the transmission capacity of at least one frictional shift element is increased.

Abstract: A method is described for the operation of a transmission device (1) with a plurality of frictional shift elements (A, D, E, F) and at least one interlocking shift element (B, C) for obtaining various gear ratios. When a command is received for a gearshift during which the interlocking shift element (C) has to be changed from an open to a closed operating condition, the interlocking shift element (C) is at least approximately synchronized by increasing the transmission capacity of at least one frictional shift element (A) which does not have to be engaged in the force flow either to obtain the gear ratio that is to be disengaged or to obtain the gear ratio that is to be engaged.

Abstract: An method for controlling a parallel hybrid drive-train of a vehicle comprising an automatic transmission and a combustion engine which is connected, via a first shifting device, to an electrical machine, which is connected, via a drive shaft, a starting clutch positioned in the transmission. To guarantee safety and high drive comfort of the vehicle during failure of the starting clutch, shifting failures of the starting clutch are monitored. If a shifting failure is recognized, predetermined contingency procedures are initiated and executed in which either continued drive of the vehicle or slowing down of the vehicle to a stop is possible. A device comprises a monitor with a sensor and parts for analyzing and recognizing shifting failures of the starting clutch. Control parts initiate and execute contingency procedures such that a continued drive operation or slowing down of the vehicle to a stop is possible.

Abstract: A method for operating a vehicle drivetrain (1) having a drive motor (9), a transmission (10) and a drive output (2). When a gear ratio change is called for in the transmission (10), between an actually engaged gear and a target gear, one of a frictional or an interlock-type shift element is engaged in a flow of force in the vehicle drivetrain (1) and the other of an interlock-type or a frictional shift element is disengaged from the flow of force in the vehicle drivetrain (1). An actual speed that is at least equivalent to a transmission input speed is monitored and an actuation pressure of the frictional shift element involved in the shift operation and/or a torque of the drive motor (9) is/are varied to change the actual speed to a nominal speed.

Abstract: A method of controlling a hybrid drive-train of a vehicle in which the hybrid drive-train comprises a combustion engine having a driveshaft, an electric machine that can be connected to the driveshaft of the engine by a clutch, an automated transmission with an input which is connected to the rotor of the electric machine, and shifting elements for shifting between two gears. During electric driving operation with the engine stopped and the clutch disengaged, the engine can be drag-started in combination with a downshift in the transmission. Drag starting of the engine is carried out by disengaging the frictional shifting element to be disengaged to below a slipping limit, engaging the clutch until the engine reaches or exceeds its minimum starting speed, starting the engine self-starts, substantially disengaging the clutch, separately adjusting the engine and electric machine to the synchronous speed of the target gear, and fully engaging and disengaging associated shifting elements.

Abstract: A process for monitoring a direction of drive from an automatic or automated vehicle transmission at near-zero vehicle speed via an engaged gear. A desired direction of drive of the transmission is determined from an engaged gear at the time the vehicle begins motion. An actual direction of drive is determined from the transmission and if different from the desired direction of drive, an error signal is produced. The process including determining the actual drive either from a sensed rotational direction of a transmission input shaft and a sensed rotational direction of a transmission output shaft or a sensed valve setting, a sensed pressure in an transmission electro-hydraulic control system or on a transmission shifting element or from a sensed direction of rotation of a transmission gearset element or from axial movement or force of a transmission constructional element.

Abstract: A method of operating a vehicle drive train having a drive machine, a transmission apparatus having a plurality of shift elements and an output drive. The plurality of shift elements are engaged or disengaged in a power flow for achieving different transmission ratios within the transmission apparatus. The output drive is coupled to a transmission output shaft and the drive machine is coupled to a transmission input shaft of the transmission apparatus. Upon a request to interrupt power flow within the transmission apparatus, between the transmission input shaft and the transmission output shaft, a maximum number of shift elements are transferred to and/or held in an engaged operating state, and the remaining portion of the shift elements are transferred to and/or held in a disengaged operating state with the transmission output shaft being rotatable.

Abstract: A method for monitoring frictional engagement in an automatic or automated motor vehicle transmission having a hydrodynamic starter element when the transmission is in a preset neutral or parking position and the automatic or automated motor vehicle transmission controlled by this method. When the motor vehicle is at or close to a standstill in a preset neutral or parking position, the current transmission rotational input speed and a current engine rotational speed of the drive motor are determined and based on the speed ratio between the current transmission rotational input speed and the current engine rotational speed an error is found to be present if the speed ratio is less than a predefined threshold value, which is less than/equal to 1.

Abstract: A method of operating of a drivetrain, having at least a drive motor and an automatic transmission with at least five shift elements, to improve a shift speed such that during a first upshift or a first downshift, at least one required shift element is prepared such that, when a synchronization point is reached, the successive upshift or the successive downshift can be immediately carried out. The method comprises the steps of requiring, at most, two of the at least five shift elements be disengaged and a remainder of the shift elements be disengaged for each gear for transferring one of torque and force; and one of increasing and decreasing a torque of the drive motor, relative to a torque of the drive motor derived from a driver's wish, during one of the first upshift or downshift and the successive upshift or downshift to assist with an overlapped implementation of the successive upshifts or the successive downshifts.

Abstract: A method of determining a fill current value of at least one frictionally engaging shift element of an automatic transmission. The automatic transmission includes a hydrodynamic converter at which a speed ratio arises and an output shaft. In a control sequence, with a stationary output shaft, the speed ratio is influenced by changing a control current, and the fill current value is determined from the progression of the speed ratio arising during the control sequence, in conjunction with the progression of the control current.

Abstract: A method of determining a fill current value of a converter lock-up clutch of an automatic transmission. The automatic transmission comprises a hydrodynamic converter, at which a speed ratio arises, and an output shaft. In a control sequence with the output shaft being stationary, the speed ratio is influenced by changing the control current, and the fill current value is determined from the progression of the speed ratio arising, during the control sequence, in conjunction with the progression of the control current.

Abstract: A process of monitoring a drive direction of an automatic or automated vehicle transmission at near-zero vehicle speed via an engaged gear. A desired direction of drive of the transmission is determined from an engaged gear at the time the vehicle begins motion. An actual direction of drive is determined from the transmission and, if different from the desired direction of drive, an error signal is produced. The process includes determining the actual drive either from a sensed rotational direction of a transmission input shaft and a sensed rotational direction of a transmission output shaft or a sensed valve setting, a sensed pressure in an transmission electro-hydraulic control system or on a transmission shifting element or from a sensed direction of rotation of a transmission gearset element or from axial movement or force of a transmission constructional element.

Abstract: A method of actuating a gear step in an automatic or automated transmission of a motor vehicle. The gear step of the transmission and a parking lock, which immobilizes the vehicle, can be engaged as a function of a gear step (P, R, N, D) that can be selected by the driver via a controllable selector device, and as a function of other motor vehicle operating parameters. A separate operating device, which is in addition to the selector device, can activate a holding phase, in which the transmission is in a traction-free neutral position, independently of a predetermined gear step “Park” (P), “Reverse” (R), “Neutral” (N) and/or “Forward” (D) that is specified by the selector device, if the motor vehicle is at least almost at a standstill and at the same time, an ignition circuit acting on a drive motor of the motor vehicle is electrically interrupted.

Abstract: A method for the operation of a drivetrain comprising an automatic transmission, a motor and at least five shift elements in which two shift elements are engaged and three shift elements are disengaged. When carrying out an upshift or downshift, a first shift element is either disengaged or engaged, and a second shift element is engaged or disengaged. While the first upshift or downshift is being carried out, a second shift element is prepared for disengaging or engaging and a third shift element is prepared for engaging or disengaging. Actuation of the second shift element occurs by virtue of a minimum selection of a first alternative or a maximum selection a second alternative. While the first upshift or downshift is being carried out and while the second upshift or downshift is being carried out, at least one fourth shift element is kept engaged or nearly engaged.

Abstract: A method of controlling a hybrid drive-train of a vehicle in which the hybrid drive-train comprises a combustion engine having a driveshaft, an electric machine that can be connected to the driveshaft of the engine by a clutch, an automated transmission with an input which is connected to the rotor of the electric machine, and shifting elements for shifting between two gears. During electric driving operation with the engine stopped and the clutch disengaged, the engine can be drag-started in combination with a downshift in the transmission. Drag starting of the engine is carried out by disengaging the frictional shifting element to be disengaged to below a slipping limit, engaging the clutch until the engine reaches or exceeds its minimum starting speed, starting the engine self-starts, substantially disengaging the clutch, separately adjusting the engine and electric machine to the synchronous speed of the target gear, and fully engaging and disengaging associated shifting elements.

Abstract: A method for operating an automatic transmission of a motor vehicle, in particular a variable-speed automatic transmission. The automatic transmission has five shift elements and for transferring torque or force in a forward gear and in a reverse gear at least three of the five shift elements are engaged. In a neutral position of the automatic transmission, to prevent torque or force flow at least one of the shift elements that are engaged in the respective forward or reverse gear is fully disengaged.

Abstract: A method of operating a valve system of a transmission comprising part of the vehicle drive train through a valve unit and said valve unit's electro-magnetic activator configuration. In a transmission's hydraulic system and is part of the vehicle drive train, its hydraulic pressure value (p_EDS) can be employed and adjusted through a valve unit configuration by applying a pulse-width-modulated current signal (i_EDS) to the electro-magnetic activator system. The pulse-width modulated current signal (i_EDS) and its amplitude (A) and/or its pulse duration (pw1) will periodically change, during the applied Dither-Modulation, by maintaining the required pressure value (p_EDS) at the same time, whereby a lengthwise movable anchor, which is attached a valve shaft of the valve system, receives hereby an imposed vibrating oscillation. According to the invention, the Dither-Modulation is activated or deactivated during pre-defined operating conditions of the vehicle drive train.