A vehicle transmission includes a plurality of friction clutches and a selectable one-way clutch. The transmission also includes a controller programmed to, in response to detecting a component fault, switch the selectable one-way clutch from a passive state to an active state by commanding engagement of a first subset of the friction clutches to establish a slip elimination state. The controller is also programmed to, following establishment of the slip elimination state, command the selectable one-way clutch to the active state.

A coupling assembly has a second coupling member mounted for rotation and a first coupling member having a speed sensor to sense a speed of rotation of the second coupling member. The coupling assembly further has a forward and a reverse locking element movable between (i) a coupling position in which the locking elements engage the second coupling member to thereby prevent rotation of the second coupling member in opposite first and second directions and (ii) a non-coupling position. Upon the speed of rotation of the second coupling member decreasing to be lower than a hill-hold speed threshold, the reverse locking element is moved to the coupling position while the forward locking element is maintained in the non-coupling position. Irrespective of a Park command, the locking elements are maintained in the non-coupling position while the speed of rotation of the second coupling member is greater than a park speed threshold.

An oil pump is connected to an electric motor and receives driving power, and the oil pump operates normally in a forward direction at normal times regardless of whether the electric motor operates in the forward or reverse direction thereof. Therefore, according to A system for operating an oil pump for a vehicle, the oil pump, which operates in conjunction with the electric motor, is applied, which reduces costs in comparison with an electric oil pump. Furthermore, regardless of whether the electric motor operates in the forward or reverse direction, the oil pump operates normally, which normally circulates oil and stabilizes components of an oil system.

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 selectable one-way clutch includes: a pocket plate; struts; a notch plate having a plurality of notches; and a selector plate that has a plurality of window holes. The strut includes a protrusion formed at a center thereof in a radial direction of the selectable one-way clutch. The selector plate has a cutout groove extending from an inner surface of the window hole along a formation direction of the protrusion. When the selectable one-way clutch is disengaged, the cutout groove is fitted on the protrusion, and the strut and the selector plate overlap each other in a rotational axis direction of the selectable one-way clutch.

A propulsion system includes a propulsor having a driveshaft, an electric machine coupled to the driveshaft of the propulsor, and a combustion engine having an output shaft. The propulsion system additionally includes a one-way clutch operable with at least one of the driveshaft of the propulsor and the output shaft of the combustion engine. The one-way clutch allows for a differential angular velocity of the driveshaft relative to the output shaft in a first circumferential direction and prevents a differential angular velocity of the driveshaft relative to the output shaft in a second circumferential direction.

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.

Systems and methods are shown for electrically controllably transmitting power from a motor involving electrically controllably coupling the first input hub to a shuttle so that power is transmitted from the first input hub to the shuttle, providing for one-way rotation between the shuttle and a stationary chassis, and coupling the shuttle to an output hub with a spring such that energy is stored and released from the spring as the output hub rotates. Examples are shown that include controlling engaged and disengaged time intervals of the first input hub and shuttle to maintain a torque level at the output hub, such as by utilizing pulse width modulation or pulse frequency modulation. Examples are also shown involving electroadhesively coupling the first input hub to the shuttle.

An electro-magnetically actuated pawl clutch is adapted to establish a fixed overdrive ratio in a powersplit type hybrid gearing arrangement. In a first embodiment, the pawl clutch holds a member against rotation in one direction when engaged and permits rotation in the other direction. In a second embodiment, the pawl clutch prevents relative rotation between two rotatable members in one direction when engaged and permits relative rotation in the other direction. In either embodiment, the coil is stationary.

A control device for a selectable one-way clutch includes a pocket plate; a notch plate rotating relative to the pocket plate; a selector plate between the pocket plate and the notch plate rotating coaxially with the notch plate to change between a state allowing engagement members to pass through respective openings and to stand up from a side close to the pocket plate toward a side close to the notch plate and a state allowing the housing recesses to house the engagement members; and a motion detection unit detecting a motion of the selector plate. Further, when an unintended motion of the selector plate is detected, the pocket plate and the notch plate to rotate differentially at a rotation speed equal to or less than a predetermined absolute value, and the selectable one-way clutch to fall into a state of ratchet or into a state of overrun.