A method and system for controlling clutch friction elements of an automatic transmission is provided. The method includes retrieving information about shift clutches from a data storage unit and acquiring information required to predict a temperature of a friction element for each shift clutch, deriving a predicted temperature value of a friction element for each shift clutch by using the information about the shift clutches and the information required to predict the temperature of the friction element, predicting whether or not overheating occurs for each shift clutch by comparing the derived predicted temperature value of the friction element for each shift clutch with an allowable temperature set for each shift clutch, and determining a target shift stage while avoiding the overheating clutch with a predicted temperature value exceeding the allowable temperature, through switching to an avoidance shift mode.

A control apparatus for a drive-force transmitting apparatus that defines a first drive-force transmitting path that is to be established by engagements of a first frictional engagement device and a dog clutch and a second drive-force transmitting path in which a lower gear ratio is provided than in the first drive-force transmitting path. In a second running mode with the second drive-force transmitting path being established, the control apparatus places the dog clutch in a released state when a vehicle running speed is higher than a first speed value, and places the dog clutch in an engaged state when the running speed is not higher than the first speed value. Further, in the second running mode, the control apparatus inhibits the dog clutch from being switched to the released state when an accumulated heat quantity in a synchromesh mechanism of the dog clutch is larger than a first quantity value.

A method for operating a drive device for a motor vehicle, which has an internal combustion engine and an electric motor. A drive shaft of the internal combustion engine can be coupled to a motor shaft of the electric motor by a shift clutch. The shift clutch is adjusted to a desired clutch torque over a dragging period for startup of the internal combustion engine. Prior to the startup, a quantity of heat that is expected to accrue in the shift clutch during the startup is predicted and, when the predicted quantity of heat exceeds a limit value, at least one operating parameter of the drive device that influences the startup is chosen in such a way that the quantity of heat expected to accrue is reduced.

A control device for a vehicle includes an electronic control unit configured to control release of a predetermined engaging device configured to selectively engage a rotating member of a loaded part that participates in power transmission in a predetermined gear stage among a plurality of engaging devices with a rotating member of a non-loaded part that does not participate in the power transmission in the predetermined gear stage, at the time of selection of the predetermined gear stage of a stepped transmission, and control the predetermined engaging device such that an engagement pressure for bringing the predetermined engaging device into a weak slip state in a range that does not affect the selection of the predetermined gear stage is added, at the time of the selection of the predetermined gear stage and in a predetermined operational state.

A vehicle includes a clutch to couple a motor and transmission, and a controller that, in response to a regenerative braking request and a temperature being within a first range, partially capacitizes the clutch for regenerative torque transfer therethrough with slip, and in response to another regenerative braking request and the temperature being within a second range less than the first, fully capacitizes the clutch prior to regenerative torque transfer therethough to preclude slip.

A method for operating a hybrid vehicle having a prime mover including an internal combustion engine and an electric machine, the vehicle further having a transmission connected between the prime mover and a driven end and including multiple shift elements, the vehicle further having a separating clutch connected between the internal combustion engine and the electric machine, and a starting component which is provided by a separate launch clutch or by a shift element of the transmission. The method includes monitoring a rotational speed of one of the internal combustion engine, the electric machine, the transmission, or the driven end during travel with the internal combustion engine running and the separating clutch engaged. The method further includes determining an increase in driving resistance, and decoupling the internal combustion engine when the monitored rotational speed falls below or reaches a first limiting value by disengaging the separating clutch.

The invention relates to a method for operating a vehicle drive train (1) comprising a prime mover (2), comprising a transmission (3), and comprising a driven end (4). A friction-locking shift element (10) is provided, the power transmission capacity of which is variable and, with the aid of which, at least a portion of the torque transmitted in the vehicle drive train (1) can be transmitted between a transmission output shaft (8) and an area (6) of the driven end (4). One shift-element half is operatively connected to the transmission output shaft (8) and the other shift-element half is operatively connected to the area (6) of the driven end (4). The rotational speed of the transmission output shaft (8) is determined as a function of the rotational speed in the area (6) of the driven end (4) and also as a function of the rotational speed of the prime mover (2) and the ratio currently engaged in the area of the transmission (3). In the event of a deviation between the rotational speed of the transmission output shaft (8) determined on the output end and the rotational speed of the transmission output shaft (8) determined on the transmission-input end, which is greater than or equal to a threshold value and/or an operating temperature in the area of the friction-locking shift element (10), which is greater than or equal to a limiting value, measures reducing loads of the friction-locking shift element (10) are initiated.

A driver assistance device for a motor vehicle with a drive assembly, which can be connected to a drivetrain via a clutch that can be activated by an actuator. The clutch being a component of an electronically controlled clutch system, in which a clutch pedal sensor detects an actuation of a clutch pedal on the driver's side and in which an analysis unit determines, in a first control mode on the basis of the detected clutch pedal actuation, a clutch torque and actuates the clutch with a corresponding clutch signal. For an adjustment of the clutch response on the driver's side, the analysis unit is associated with an input unit, for the actuation of which, on the driver's side, it is possible to shift between the first control mode and at least one second control mode.

A drive system of a hybrid vehicle including an internal combustion engine, a first motor-generator, a first power transmission path and a second power transmission path, a power division mechanism, a second motor-generator, a clutch portion provided at the power transmission path to make or break the first power transmission path, and a microprocessor. The microprocessor is configured to determine whether a drive in a region exceeding a characteristic curve of a driving force defined by a sum of a driving force output through the first power transmission path and a driving force of the second motor-generator at a low vehicle speed is necessary, and to control the clutch portion to a half-clutch state when determining that the drive in the region is necessary, while connecting or disconnecting the clutch portion when determining that the drive in the region is not necessary.

A gear change control device and method thereof are provided. The gear change control device is a target torque control device that sets a target torque of a motor outputting a torque to a multilevel transmission having a torque converter and a lockup clutch. In a case when the lockup clutch is in a fastened state and during upshifting gear change, target torque reduction control is executed for reducing the target torque of the motor such that the output of the motor becomes a torque at which a heat generation temperature of the lockup clutch does not exceed an allowable temperature. If the lockup clutch is fastened, threshold value changing control is executed for changing threshold value of a rotation speed of the motor or the input shaft when the gear range is shifted to the side of higher range during upshifting gear change to a higher rotation speed.