A transmission includes a selectable one-way clutch with an active state and a passive state. To avoid occupant discomfort and hardware damage, transitions from the passive state to the active state must only be commanded when no or very little slip is present across the selectable one-way clutch. Several methods are presented to eliminate slip, depending on vehicle speed. When the vehicle is stationary, full engagement of a clutch that causes slip to be proportional to vehicle speed eliminates slip. When the vehicle is moving backwards, partial engagement of the above clutch eliminates slip. When the vehicle is moving forwards, full engagement of all but one clutch of a tie-up condition and partial engagement of the remaining clutch of the tie-up condition brings the vehicle to a stop and eliminates slip.

A control device that controls an automatic transmission is provided, in which device the automatic transmission includes a variator disposed in a power transmission path between a driving source and a driving wheel of a vehicle, and a friction engaging element disposed between the variator and the driving wheel, in a manner capable of transmitting a power disconnectably via the power transmission path. The control device increases a speed ratio of the variator toward a predetermined target speed ratio with disengaging the friction engaging element during a vehicle stop of the vehicle, and executes a learning regarding a hydraulic control of the friction engaging element when the friction engaging element is disengaged during the vehicle stop. The control device decreases the target speed ratio at a time of learning when the learning is executed during the vehicle stop, compared to a time of vehicle stop other than the time of learning.

A control device that controls an automatic transmission is provided, in which device the automatic transmission includes a variator disposed in a power transmission path between a driving source and a driving wheel of a vehicle, and a friction engaging element disposed between the variator and the driving wheel, in a manner capable of transmitting a power disconnectably via the power transmission path. The control device increases a speed ratio of the variator toward a predetermined target speed ratio with disengaging the friction engaging element during a vehicle stop of the vehicle, and executes a learning regarding a hydraulic control of the friction engaging element when the friction engaging element is disengaged during the vehicle stop. The control device decreases the target speed ratio at a time of learning when the learning is executed during the vehicle stop, compared to a time of vehicle stop other than the time of learning.

In a case where a predetermined switching operation to a state in which a traveling position is selected from a state in which another shift position of a mechanical transmission device is selected is performed by a driver, a quick engagement command to quickly engage a predetermined engagement device is performed in a state in which output of a predetermined torque is stopped, and then a rapid garage control of increasing a rotation speed of an electric motor at a rotation speed equal to or higher than a predetermined rotation speed is executed. The rapid garage control is executed in a case where a predetermined start condition is established.

Disclosed is method for operating a multi-gear vehicle transmission having a plurality of shifting elements (A, B, C, D, E) for engaging gears of the vehicle transmission. In a neutral gear a transmission input (1) and a transmission output (2) of the vehicle transmission are decoupled from one another. In a driving gear the transmission input (1) and the transmission output (2) of the vehicle transmission are coupled with one another by closing the shifting elements (A, B, C, D, E) associated with the driving gear in order to propel the vehicle. When the neutral gear is engaged, a transmission condition is determined, and if a transmission condition with elevated drag losses exists, then in addition to the shifting elements (A, B, C, D, E) of a driving gear, at least one further shifting element (A, B, C, D, E) of the vehicle transmission is closed.

Disclosed is method for operating a multi-gear vehicle transmission having a plurality of shifting elements (A, B, C, D, E) for engaging gears of the vehicle transmission. In a neutral gear a transmission input (1) and a transmission output (2) of the vehicle transmission are decoupled from one another. In a driving gear the transmission input (1) and the transmission output (2) of the vehicle transmission are coupled with one another by closing the shifting elements (A, B, C, D, E) associated with the driving gear in order to propel the vehicle. When the neutral gear is engaged, a transmission condition is determined, and if a transmission condition with elevated drag losses exists, then in addition to the shifting elements (A, B, C, D, E) of a driving gear, at least one further shifting element (A, B, C, D, E) of the vehicle transmission is closed.

A control system of a vehicle is provided, which includes an automatic transmission, a brake controller, and a processor configured to execute a neutral idle controlling module, a hydraulic pressure calculating module, a hydraulic pressure controlling module to calculate a target value of hydraulic pressure supplied to a frictional engageable element according to a given parameter, and a brake hold controlling module. The calculating module includes a first calculating submodule executed to calculate the target value in a period from an issuance of a vehicle start request when a neutral idle control is executed and a brake hold control is not executed in a vehicle stopped state until the frictional engageable element is engaged, and a second calculating submodule executed to calculate the target value so that a calculated value is lower than in the first calculation when the value of the parameter is the same.

A dual clutch automatic transmission includes a one-way clutch provided in a driving force transmission path that establishes a certain gear ratio in a first set of gear ratios. A driving transmission direction of the one-way clutch is set such that a rotation inputted from a wheel side to an output member in a predetermined rotational direction is transmitted to the input shaft. The predetermined rotational direction corresponds to a backward movement of a vehicle. On condition that the vehicle has stopped, backward movement prevention control of causing the switching mechanism to engage a transmission gear for another gear ratio in the first set with the input shaft can be executed.

A dual clutch automatic transmission includes a one-way clutch provided in a driving force transmission path that establishes a certain gear ratio in a first set of gear ratios. A driving transmission direction of the one-way clutch is set such that a rotation inputted from a wheel side to an output member in a predetermined rotational direction is transmitted to the input shaft. The predetermined rotational direction corresponds to a backward movement of a vehicle. On condition that the vehicle has stopped, backward movement prevention control of causing the switching mechanism to engage a transmission gear for another gear ratio in the first set with the input shaft can be executed.

A dual clutch automatic transmission includes a one-way clutch provided in a driving force transmission path that establishes a certain gear ratio in a first set of gear ratios. A driving transmission direction of the one-way clutch is set such that a rotation inputted from a wheel side to an output member in a predetermined rotational direction is transmitted to the input shaft. The predetermined rotational direction corresponds to a backward movement of a vehicle. On condition that the traveling state of the vehicle reaches a predetermined deceleration state, switching control of setting the gears for the first set to a neutral position can be executed.