A power transmission apparatus may include a first motor-generator including a first stator fixed to a first housing, and a first rotor; a second motor-generator including a second stator fixed to a second housing and a second rotor; a first planetary gear set including first and third rotation elements connected to the first rotor and a first wheel, respectively, and a third rotation element; a second planetary gear set including fourth, fifth and sixth rotation elements connected to the second rotor, a second wheel, and the third rotation element, respectively; a first clutch selectively locking up the first planetary gear set by selectively connecting two out of the first to third rotation elements; a second clutch selectively locking up the second planetary gear set by selectively connecting two of the fourth to sixth rotation elements; and a brake selectively fixing the third and sixth rotation elements to a third housing.

A drive system includes a first planetary gear set selectively coupled to a first electromagnetic device, a second planetary gear set coupled to a second electromagnetic device and directly coupled to the first planetary gear set, an engine directly coupled to the first planetary gear set with a connecting shaft, and an output shaft coupled to the first planetary gear set. The first and second electromagnetic devices include a first shaft and a second shaft, respectively. The connecting shaft extends through the second electromagnetic device and through the second planetary gear set to the first planetary gear set. The first shaft, the second shaft, the first planetary gear set, the second planetary gear set, the connecting shaft, and the output shaft are radially aligned, forming a straight-thru transmission arrangement.

A drive system includes a first planetary gear set coupled to a first electromagnetic device, a second planetary gear set coupled to a second electromagnetic device and directly coupled to the first planetary gear set, an engine directly coupled to the first planetary gear set with a connecting shaft, and an output shaft coupled to the first planetary gear set. The first and second electromagnetic devices include a first shaft and a second shaft, respectively. The connecting shaft extends through the second electromagnetic device and through the second planetary gear set to the first planetary gear set. The first shaft, the second shaft, the first planetary gear set, the second planetary gear set, the connecting shaft, and the output shaft are radially aligned, forming a straight-thru transmission arrangement.

A power transmission apparatus has a power distribution mechanism which is connected to an engine and a first motor-generator an in which at least three rotation elements enable to rotate in differential motions to one another, a power combining mechanism which is connected to the power distribution mechanism, a second motor-generator and an output shaft and in which four rotation elements enable to rotate in differential motions to one another, a brake mechanism which enables to selectively fix a rotation element of the power combining mechanism and a brake mechanism which enables to selectively fix a rotation element of the power combining mechanism which is connected to the engine.

A rotary electric machine is disposed coaxially with an input member more toward a first side in an axial direction than a first gear that meshes with a second gear. A third gear rotates integrally with second and fourth gears that mesh with third gear more toward second side in axial direction than first and second gears. An axis of a counter gear mechanism is below axis of rotary electric machine and axis of differential gear mechanism. An inverter device more toward first side in axial direction than fourth gear and above axis of differential gear mechanism while that inverter device overlaps fourth gear as seen in axial direction. A specific portion of inverter device is between rotary electric machine and fourth gear in axial direction, such that specific portion overlaps counter gear mechanism as seen in up-down direction and overlaps rotary electric machine as seen in axial direction.

A drive system includes: a first planetary gear unit, in which a carrier is connected to an internal combustion engine, a sun gear is connected to a first MG, and a ring gear is connected, via a first drive gear and a first driven gear, to a counter shaft; and a second planetary gear unit, in which a brake is provided to a sun gear, a carrier is connected to the internal combustion engine, and a ring gear is connected, via a second drive gear and a second driven gear, to the counter shaft. A gear ratio of the first drive gear and the first driven gear is larger than a gear ratio of the second drive gear and the second driven gear.

A control unit embedded in a work vehicle includes a clutch controlling unit and a motor controlling unit. The clutch controlling unit is configured to disengage a first clutch in a condition that the first clutch is engaged and a second clutch is disengaged, when a first moving direction inputted through a forward/rearward movement switch operating device as an instruction of the operator and a second moving direction determined based on a vehicle speed detected by a vehicle speed detecting unit are different from each other, and in addition, when and the vehicle speed falls in a preliminarily set first range. The motor controlling unit is configured to control a motor to reduce a relative rotational speed of the second clutch after the first clutch is disengaged.

Disclosed are electrically variable transmissions (EVT), methods for making and for using EVTs, and hybrid electric vehicles with EVTs. Presented is a multi-speed power transmission for a motor vehicle with an engine, two electric motors, and a final drive. The transmission includes an input member connectable to the engine, an output member connectable to the final drive, and a stationary member connectable to a gear train. First and second torque-transmitting devices (TTD) respectively connect to the first and second motors. The transmission also includes a compound planetary gear arrangement with four junction points defined by two interconnected planetary gear sets. The first TTD selectively connects the first motor to the first junction point, while the second TTD selectively connects the second motor to the fourth junction point via the gear train. The input member connects at the second junction point, whereas the output member connects at the third junction point.

A transmission for a motor vehicle has an input shaft, output shaft, first and second minus planetary gear sets, and first electric machine with a rotationally fixed stator and a rotatable rotor connectable to the input shaft. The first planetary gear set is stepped and has planet gears of a larger and a smaller effective diameter. In the first planetary gear set, first sun gear engages the larger planet gears and is connected or connectable to the rotor; second sun gear engages the smaller planet gears and is connected to a sun gear of the second planetary gear set and connectable to the input shaft; a carrier is connected to a ring gear of the second planetary gear set; and a ring gear is rotationally fixable. In the second planetary gear set, the carrier is connectable to the input shaft and the ring gear is connected to the output shaft.

A control device that switchably has a first drive mode which is attained with the fixing mechanism being in the non-fixing state and in which a rotational speed of the input is steplessly shifted and transmitted to the output and torque of the second rotating electrical machine is transmitted to the output, and a second drive mode which is attained with the fixing mechanism being in the fixing state and the decoupling mechanism being in the non-transmitting state and in which, with the second rotating electrical machine being decoupled from the output, the rotational speed of the input is shifted according to a gear ratio of the differential gear unit and transmitted to the output.