A vehicle driving device mounted on a hybrid vehicle includes an engine coupled to wheels of the vehicle via a power transmission path, a transmission mechanism disposed on the power transmission path, a motor generator, a first power transmission mechanism, and a second power transmission mechanism. The motor generator is disposed on a path coupling the engine and transmission mechanism, the first power transmission mechanism is disposed on a path coupling the engine and motor generator, the second power transmission mechanism is disposed on a path coupling the motor generator and transmission mechanism. These paths are included in the power transmission path. The first power transmission mechanism includes a large-diameter rotator and a small-diameter rotator coupled to the engine and the motor generator respectively. The second power transmission mechanism includes a small-diameter rotator and a large-diameter rotator coupled to the motor generator and the transmission mechanism respectively.

A shifting assembly for a transmission at least has a first component, a second component, and a third component, the components interacting according to the shift state in that a friction clutch is arranged between the first component and the second component, a positively-locking clutch is arranged between the second component and the third component, and a freewheel unit is arranged between the second component and the third component. A connection means is provided which connects a clutch part of the friction clutch to a clutch part of the positively-locking clutch.

Systems and methods for controlling transmissions having CVTs are disclosed with multiple modes and gearing arrangements for range enhancements, where embodiments include synchronous shifting to allow the transmission to achieve a continuous range of transmission ratios, while minimizing “empty” cycling of the CVT during mode shifts. Embodiments provide for wide ratio range and performance and efficiency flexibility, while maximizing CVT usage through synchronous shifting.

Methods and systems are provided for engaging and disengaging an electromagnetic clutch of a two-speed accessory drive of an engine of a vehicle. In one example, a method comprises, responsive to an electrical demand being higher than a threshold electrical demand, operating an electric machine of the vehicle in a motor mode to reduce a speed of a grounding gear of a planetary gear set of a two-speed accessory drive (TSAD) of the vehicle; and engaging an electromagnetic clutch responsive to the speed of the grounding gear reaching a clutch engagement threshold speed.

A hydraulic pressure calculation apparatus is applied to a gear shifting system including a transmission configured to switch between a connected state and a disconnected state of a friction engagement element depending on a hydraulic pressure supplied from a hydraulic circuit, and a hydraulic controller configured to control the hydraulic circuit. The hydraulic pressure calculation apparatus includes a memory and a processor. The memory stores pieces of mapping data of a plurality of phases obtained by dividing a period from a start to an end of switching between the connected state and the disconnected state of the friction engagement element. Each piece of the mapping data defines a mapping. The processor is configured to output, as an output variable, an estimated hydraulic pressure variable indicating an estimated value of an actual hydraulic pressure supplied from the hydraulic circuit to the friction engagement element.

A method and system are provided for shifting a vehicle transmission having several members. Each member is a first, second, or third node of a planetary gear set (of multiple planetary gear sets), or an input, output, or stationary member. A first torque transmitting mechanism is applied to transfer torque between first and second members in a low gear state. In some versions, a second torque transmitting mechanism is applied in the low gear state without substantially transferring torque between third and fourth members, and then the second torque transmitting mechanism is disengaged. A third torque transmitting mechanism is then applied without substantially transferring torque between the third and fourth members in the low gear state. The transmission is upshifted by disengaging the first torque transmitting mechanism, keeping the third torque transmitting mechanism applied, and applying the second torque transmitting mechanism to transfer torque between the third and fourth members.

An automatic transmission is provided. The transmission includes clutches coaxially arranged in layers in a radial direction of the transmission. The transmission includes a piston provided to each clutch, the pistons being aligned in the radial direction on a same plane perpendicular to an axis of the transmission, without overlapping with each other in an axial view. The transmission includes a common rotational member having a wall, commonly used for the clutches, and disposed at a predetermined position of the transmission in an axial direction, wherein the wall is formed along the plane. The transmission includes operational hydraulic passages parallely arranged in the wall of the common rotational member in a circumferential direction of the transmission on the same plane perpendicular to the axis, each of the operational hydraulic passages communicating with one of operational hydraulic chambers of the respective clutches.

A drive transmission device includes a clutch mechanism. The clutch mechanism includes a drive transmission member that is coupled to a first rotation member via a torque limiter and is arranged in a fitting part of a second rotation member and a third rotation member, and a transmission member moving part that includes a first gap and a second gap, the first gap being formed in the fitting part and having a width wider than the thickness of the drive transmission member and the second gap being formed in the fitting part and having a width that is equal to or smaller than the thickness of the drive transmission member, the transmission member moving part being formed in such a way that the width thereof becomes smaller about a rotation axis in the fitting part.

In a case where intermediate gear stage fault occurs, an electronic control unit determines, using a predetermined relationship for determining gear stage switching between a gear stage on a lower side than the intermediate gear stage by one stage and the intermediate gear stage, whether or not to execute gear stage switching between the low gear stage and a gear stage on a higher than the intermediate gear stage by one stage. For example, compared to using a relationship for determining gear stage switching between a gear stage on the higher side and the intermediate gear stage, it is possible to execute gear stage switching between a gear stage on the lower side and a gear stage on the higher side in a low vehicle speed region. Therefore, it is possible to suppress the influence on vehicle behavior.

A transmission apparatus of a hybrid vehicle is provided. The apparatus includes a planetary gear set including a first rotation element connected to an engine, a second rotation element connected to a first motor/generator, and a third rotation element connected to a second motor/generator. An output gear is connected to any one of the second and third rotation elements and a two-way clutch is mounted at the first rotation element. The clutch limits D stage rotation in a first side direction or limits R stage rotation in a second side direction selectively based on a position of a lever. Accordingly, the clutch performs a failsafe function by preventing a shifting stage from being applied to the R stage when the engine is driven.