Methods and system are described for changing a driveline gear range from a lower gear range to a higher gear range. The driveline may include two electric machines and four clutches in a four wheel drive configuration. The methods and systems permit a driveline to change from a lower gear range to a higher gear range in a way that may reduce torque disturbances that may result from gear lash.

In a control device for a vehicle including: a dog clutch mechanism that is disposed in a power transmission path in which a driving force is transmitted from an engine to a wheel and is operated by a hydraulic actuator; and an electric oil pump that supplies hydraulic pressure to the hydraulic actuator, rotation of the engine is stopped in a state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine stop operation, the rotation of the engine is started in the state in which the dog clutch mechanism is engaged by the hydraulic pressure supplied from the electric oil pump at a time during an engine restart operation, hence occurrence of up-lock of the dog clutch mechanism is prevented.

A control apparatus for a transmission including a gear engagement commander outputting a gear engagement command of a sleeve, an actuator controller controlling an actuator to move the sleeve from a neutral position to a gear engaging position when the gear engagement command is output, a gear engagement determiner determining whether an engagement of the sleeve is prevented in a course of moving the sleeve from the neutral position to the gear engaging position; and a motor controlling an electric motor to rotate a rotating shaft so as to change a rotational position of movable dog teeth relative to passive dog teeth when it is determined that the engagement of the sleeve is prevented.

A drive-train for a vehicle with at least one electric drive, which can be coupled via a driveshaft (2) to at least a first transmission ratio stage (i1) and a second transmission ratio stage (i2). At least one shifting mechanism is provided for engaging the transmission ratio stages (i1, i2). To carry out powershifts, the shifting mechanism includes at least one interlocking shifting element (5) and at least one frictional shifting element (6, 6A). Each of the transmission ratio stages (i1, i2) can be engaged by the interlocking shifting element (5) and at least one of the transmission ratio stages (i2) can be engaged both by the interlocking shifting element (5) and by the frictional shifting element (6). Methods for carrying out a powershift, between a frictional shifting element (6, 6A) and an interlocking shifting element (5) in the drive-train, are also disclosed.

A method for operating an automatic transmission includes determining at least one of an elapsed time from adjusting a first one of at least one positive-locking shift element towards a closed configuration or a differential speed rotation of the first one of the at least one positive-locking shift element and shifting the automatic transmission to a substitute gear if the elapsed time from adjusting the first one of the at least one positive-locking shift element towards the closed configuration reaches or exceeds a time limit and/or the differential speed rotation of the first one of the at least one positive-locking shift element reaches or exceeds a rotational speed limit. A related transmission control device for an automatic transmission is also provided.

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. A controller controls the shift actuator utilizing an actuating pulse and an opposing pulse.

When a hybrid electric vehicle in which an automatic manual transmission (AMT) is equipped stops and then re-starts, when a starting stage of the AMT is not implemented, an RPM of a driving motor which is directly connected to an input shaft is changed so that a torque applied to an input shaft of the AMT is increased or decreased, and thus even though a blocking phenomenon occurs when an AMT-HEV stops and then re-starts after an engine re-starts, the torque transferred from the driving motor to the input shaft is appropriately increased and decreased and thus a gear restricted to the input shaft differently rotates from a synchronizer.

A gear engagement method for a hybrid vehicle includes detecting whether or not baulking occurs when a controller attempts to engage a target gear via a synchronizer. The gear engagement method also includes checking, by the controller, for a stationary state of the vehicle if the result of the detecting shows that there is baulking. The gear engagement method also includes engaging, by the controller via the synchronizer, a different gear that shares a same input shaft with the target gear if the result of the checking shows that the vehicle is in a stationary state. The gear engagement method also includes reattempting an engagement with the target gear after disengaging the different gear. The disengaging and the reattempting are performed by the controller via the synchronizer after the engaging.

A control device and a method for controlling a vehicle powertrain to overcome, or avoid, a cog-to-cog condition during gear shifting is provided. The method comprises, when an input shaft of the gearbox is rotating, controlling a synchromesh arrangement so as to induce a difference in rotational speed between a first gear wheel and a first coupling sleeve arranged to lock the first gear wheel to a main shaft of the gearbox by at least partly engaging the first gear wheel or a second gear wheel to the input shaft. Furthermore, a computer program, a computer-readable medium and a vehicle are provided.

An engine transmission is provided with an interference member that is configured to interfere with one of a low-gear clutch sleeve and a high-gear clutch sleeve so that when one of the low-gear clutch sleeve and the high-gear clutch sleeve is at an engagement position, the other one of the low-gear clutch sleeve and the high-gear clutch sleeve cannot move to an engagement position.