A power transmission device for a vehicle includes a first power transmission path that is provided between an engine and a driving wheel, a second power transmission path that is provided in parallel with the first power transmission path, and an electronic control unit. The electronic control unit changes over a secondary clutch to a one-way mode while releasing a first clutch, when a request is made to change over a power transmission path between the engine and the driving wheel from the first power transmission path to the second power transmission path at a time of a predetermined state. The electronic control unit is configured to engage a second clutch when the secondary clutch is changed over to the one-way mode.

A method for operating a vehicle drivetrain (1) includes proceeding, in the presence of the demand for activation of the engine start-stop function of the vehicle drivetrain (1) and a simultaneously shut-down drive machine (2), from an operating state of the vehicle drivetrain (1) during which a sailing operating function of the vehicle drivetrain (1) is active, during which the drive machine (2) is decoupled from the drive output (3), during which the positively engaging shift element (F) is open and during which a rotational speed (n_ab) of the drive output (3) is higher than a defined rotational speed at which a rotational speed difference between shift element halves of the positively engaging shift element (F) lies within a rotational speed range within which the positively engaging shift element (F) is transferrable into the closed operating state, and actuating the positively engaging shift element (F) in a closing direction no later than when the defined rotational speed is reached.

A vehicle driveline component having a housing, first and second shafts supported by the housing for rotation about a rotary axis, a two-speed transmission in a power transmission path between the first and second shafts, a shift fork and a failsafe spring. The two-speed transmission has a movable member that is movable along the rotary axis between a high-speed position, in which the two-speed transmission operates in a first gear ratio, and a low-speed position in which the two-speed transmission operates in a second gear ratio that provides a higher speed reduction between the first and second shafts than the first gear ratio. The shift fork is coupled to the movable member for movement therewith along the rotary axis. The failsafe spring is disposed coaxially about the rotary axis and biases the movable member toward the high-speed position.

A hydraulic control system for a transmission of a motor vehicle includes a source of pressurized hydraulic fluid that communicates with an analog electronic transmission range selection (ETRS) subsystem or a manual valve. The ETRS subsystem includes an ETRS valve, a park servo, a park mechanism, a mode valve, and a plurality of solenoids. The ETRS and manual valve communicate with a clutch actuator subsystem that engages a one-way clutch and six clutches/brakes.

A method for operating a vehicle drivetrain (1) includes decoupling, in the presence of a demand for realizing a sailing operating state of the vehicle drivetrain (1) during which a drive machine (2) is active and the power flow between the drive machine (2) and a drive output (3) is disconnected in a gearbox (4), the active drive machine (2) from the drive output (3) by opening of one of a plurality of shift elements (A to F) that is held in a closed operating state in order to realize the operating state present before the demand for decoupling of the active drive machine (2). The method also includes then actuating the plurality of shift elements (A to F) in a manner dependent on the present operating state profile of the vehicle drivetrain (1) and with the active drive machine (2) decoupled from the drive output (3).

A gear-hydraulic-rhombic pyramid integrated multi-mode hybrid transmission device includes an input assembly, a hydraulic transmission mechanism, a front planetary gear mechanism, a rhombic pyramid-type continuously variable transmission mechanism, a rear planetary gear mechanism, an output assembly, a clutch assembly, and a brake assembly. The clutch assembly connects an output end of the input assembly to an input end of the hydraulic transmission mechanism and an input end of the front planetary gear mechanism. The clutch assembly connects an output end of the hydraulic transmission mechanism to the front planetary gear mechanism and the rear planetary gear mechanism. The clutch assembly connects the front planetary gear mechanism, the rhombic pyramid-type continuously variable transmission mechanism, the rear planetary gear mechanism, and the output assembly in sequence. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input assembly and the output assembly.

A gear-hydraulic-rhombic pyramid integrated multi-mode hybrid transmission device includes an input assembly, a hydraulic transmission mechanism, a front planetary gear mechanism, a rhombic pyramid-type continuously variable transmission mechanism, a rear planetary gear mechanism, an output assembly, a clutch assembly, and a brake assembly. The clutch assembly connects an output end of the input assembly to an input end of the hydraulic transmission mechanism and an input end of the front planetary gear mechanism. The clutch assembly connects an output end of the hydraulic transmission mechanism to the front planetary gear mechanism and the rear planetary gear mechanism. The clutch assembly connects the front planetary gear mechanism, the rhombic pyramid-type continuously variable transmission mechanism, the rear planetary gear mechanism, and the output assembly in sequence. The clutch assembly and the brake assembly provide a continuous transmission ratio between the input assembly and the output assembly.

A hydraulic control system for a transmission of a motor vehicle includes a source of pressurized hydraulic fluid that communicates with an analog electronic transmission range selection (ETRS) subsystem or a manual valve. The ETRS subsystem includes an ETRS valve, a park servo, a park mechanism, a mode valve, and a plurality of solenoids. The ETRS and manual valve communicate with a clutch actuator subsystem that engages a one-way clutch and six clutches/brakes.

A selectable one-way clutch includes a first plate, a second plate, a claw, a selector plate and an interposition member. The claw is provided in the first plate. The claw projects from the first plate toward the second plate. The claw meshes with a recessed portion disposed in the second plate when the second plate rotates in a predetermined rotation direction and the claw projects from the first plate. The selector plate is placed so as to be adjacent to the first plate. The selector plate rotates relative to the first plate between a locked position at which the claw is projectable and a released position at which the claw is maintained. The interposition member is placed between the selector plate and the second plate. Rotation of the interposition member relative to the selector plate is restricted.

A transmission includes a stationary member, an input member, and gear sets each having a plurality of nodes. The transmission includes a first clutch that connects a node of one gear set to the stationary member to establish an L1 mode, and a second clutch that connects a node of another gear set to the stationary member to establish a 2L mode. A SOWC is connected between nodes of two gear sets, and a controller, in response to a requested shift L1-L2 shift while engine braking, executes a method to release the first clutch and thereby enters a neutral mode. The SOWC is released when slip across the first clutch exceeds a first threshold, then the first clutch reapplied when a SOWC slip level exceeds another threshold to thereby enter a 1.sup.st gear freewheeling mode. The second clutch is reapplied to enter the L2 mode and resume engine braking.