An electronic control unit is configured to: control a clutch actuator based on first phase definition that defines a plurality of stages of progress provided for each of control states of the clutch, the clutch being switched among the control states in a process of starting the engine; and control at least one of a motor and an engine based on second phase definition that defines a plurality of stages of progress, the second phase definition being different from the first phase definition.

A method for operating a vehicle that includes a torque converter is described. In one example, the method adjusts torque of an electric machine in response to a requested torque converter speed. The requested torque converter speed linearizes torque output of a torque converter so that vehicle wheel torque control may be improved.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

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.

Method and system for starting an internal combustion engine of a hybrid vehicle, adapted to rotate a drive shaft providing torque via a transmission unit comprising a first clutch connecting the engine to an input shaft of a gearbox connected to a torque converter connected to a second clutch connecting the torque converter to the at least one driving wheel, where the input shaft is connected to an electric machine; the method comprising: disengaging the second clutch to a predetermined torque level such that there is a slip in the second clutch; engaging the lock-up clutch; engaging the first clutch to bring the engine to a first rotational speed; disengaging the first clutch when the engine has reached the first rotational speed; starting the engine, and engaging the first clutch when the engine has started and rotates with a second rotational speed.

The invention relates to a method for controlling a drive system for an axle of a motor vehicle, wherein the drive system has at least one drive unit, a drive shaft driven by the drive unit, a first output shaft and a second output shaft, as well as a first clutch connecting the drive shaft to the first output shaft and a second clutch connecting the drive shaft to the second output shaft, and furthermore comprises a control unit for controlling the clutches, wherein the clutches are able to be operated at least at certain operating points with a micro-slip control in which a speed differential between the drive shaft and the output shaft of more than zero revolutions per minute and no more than 50 revolutions per minute is set at the respective clutch, wherein the method comprises at least the following steps: a) establishing a travel state of the motor vehicle, wherein at least the following travel states are detected: traveling straight ahead and cornering in the pull mode; b) selecting and applying a control strategy for each clutch, wherein the control strategy is different for different travel states.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

Systems and methods for operating a driveline of a hybrid vehicle are described. In one example, a torque that is produced by an engine is adjusted responsive to a transmission oil temperature and a speed of a torque converter impeller so that temperature of oil in a transmission lube circuit may be maintained at a desired temperature.

A hybrid-vehicle system includes an internal combustion engine configured to deliver a first rotational torque to a crankshaft. The first rotational torque is a maximum torque deliverable by the internal combustion engine. The hybrid-vehicle system also includes a transmission selectively rotatably coupled to the crankshaft, and an assembly including an electric machine rotatably coupled to the transmission and configured to deliver a second rotational torque directly to the transmission. The assembly also includes a one-way clutch configured to rotationally couple the crankshaft and the transmission. The assembly further includes a friction clutch moveable between an engaged state where the crankshaft and the transmission are rotationally coupled, and a disengaged state where the crankshaft and the transmission are rotationally decoupled. The friction clutch is further defined as a latching friction clutch.