Methods and systems for a transmission are provided. In one example, the transmission includes an input shaft with a first pair of gears that reside thereon, a first clutch positioned between the first pair of gears and designed to selectively rotationally couple a selected gear in the first pair of gears to the input shaft, and a layshaft with a second pair of gears fixedly coupled thereto. The transmission further includes an output shaft with a third pair of gears that reside thereon and a second clutch positioned between the third pair of gears and designed to selectively rotationally couple a selected gear in the third pair of gears to the output shaft.

A propulsion system for an electric vehicle includes an assembly of four electric propulsion machines each having a stator and a rotor having an output shaft that is movable in rotation about an axis. Also includes is a common gearwheel that is kinematically connected to the n output shafts and that is able to receive the torque provided by the electric machines so as to form a first speed reducer, and primary gearwheels able to be driven by the common gearwheel. An intermediate shaft is able to be driven by intermediate gearwheels, each primary gearwheel being kinematically connected to a corresponding intermediate gearwheel so as to form a pair of gears with which a second speed reducer is associated, and a secondary shaft that is able to drive the vehicle and that has a secondary gearwheel kinematically connected to the intermediate shaft so as to form a third speed reducer.

Drive system for an electric vehicle including a first sub-assembly of electric machines kinematically connected to a first common gear, and a second sub-assembly of electric machines kinematically connected to a second common gear. A first set of gear trains is kinematically connecting the first sub-assembly to a secondary shaft capable of driving the driving wheels of the vehicle, wherein a first selective coupling system is arranged to select a first gear train or a second gear train from a neutral position during a gear change phase. A second sub-assembly kinematically connects the second common gear to the secondary shaft. The second sub-assembly of electric machines is controlled so as to supply additional torque making it possible to compensate for the loss of torque resulting from the uncoupling of the first sub-assembly inherent in the gear change.

An embodiment hybrid powertrain for a vehicle includes a first input shaft configured to be interlocked with an engine, a second input shaft configured to be interlocked with a first motor and to be parallel to the first input shaft, a third input shaft configured to be interlocked with a second motor and to be parallel to the second input shaft, an output shaft mounted parallel to the third input shaft, a first selective mesh device configured to transmit power from the second input shaft to the output shaft at multiple different gear ratios, a second selective mesh device configured to transmit the power from the third input shaft to the output shaft at the multiple different gear ratios, and a third selective mesh device configured to transmit the power from the first input shaft to the second input shaft or the third input shaft.

In some implementations, a controller may cause a gearbox coupled to a rotor to shift between a first gear ratio and a second gear ratio one or more times. The controller may obtain a first set of position data that identifies respective first positions of a gear selector of the gearbox for each shift to the first gear ratio, and a second set of position data that identifies respective second positions of the gear selector of the gearbox for each shift to the second gear ratio. The controller may determine a first calibrated position of the gear selector for a shift to the first gear ratio based on the first set of position data and a second calibrated position of the gear selector for a shift to the second gear ratio based on the second set of position data.

A method for serial operation of a motor vehicle with a transmission having a first electric machine, which is operated as a motor for driving the motor vehicle, and a second electric machine, which is operated as a generator, includes, after a generation of a change-over signal, switching the first electric machine from the operation as a motor to the operation as a generator, and switching the second electric machine from the operation as a generator to the operation as a motor in order to drive the motor vehicle.

A counter gear mechanism includes: a fifth gear in mesh with a third gear; a sixth gear in mesh with a fourth gear; and a seventh gear in mesh with a differential input gear. The seventh gear is disposed between the fifth gear and the sixth gear in an axial direction. A switching mechanism is disposed between the third gear and the fourth gear in the axial direction. The switching mechanism makes switching among: a state in which the third gear is coupled to a second input member; a state in which the fourth gear is coupled to the second input member; and a state in which the third gear and the fourth gear are decoupled from the second input member. This structure is able to make an entirety of an apparatus compact in size in the axial direction when the apparatus includes the switching mechanism to change the speed ratio between the second input member, which is drivingly coupled to an internal combustion engine, and output members.

In some implementations, a controller may cause a gearbox coupled to a rotor to shift between a first gear ratio and a second gear ratio one or more times. The controller may obtain a first set of position data that identifies respective first positions of a gear selector of the gearbox for each shift to the first gear ratio, and a second set of position data that identifies respective second positions of the gear selector of the gearbox for each shift to the second gear ratio. The controller may determine a first calibrated position of the gear selector for a shift to the first gear ratio based on the first set of position data and a second calibrated position of the gear selector for a shift to the second gear ratio based on the second set of position data.

A fork guide groove of a drum member guides a shift fork so that a shifter member is in a reference position not engaged with first and second speed change members when the drum member is placed in a neutral position, is movable between a first speed-change position engaged with the first speed-change member and the reference position when the drum member is placed in a first operational position, and is movable between a second speed-change position engaged with the second speed-change member and the reference position when the drum member is placed in a second operational position. A slider guide groove of the drum member guides a slider member supported by a fork shaft in an axially movable manner so as not to obstruct movement of the shifter member between the reference position and the first speed-change position when the drum member is placed in the first operational position.

A power train for an electric vehicle may include a planetary gear set including three rotation elements having a first rotation element, a second rotation element and a third rotation element, wherein the first rotation element is connected to a first shaft, the second rotation element is connected to a second shaft, and the third rotation element is connected to a third shaft; a first motor mounted to selectively supply power to the first shaft in two or more gear ratios; and a second motor mounted to selectively supply power to the first shaft in two or more gear ratios. The third shaft is configured to be fixed to a transmission housing, and any two of the first shaft, the second shaft, and the third shaft are configured to be coupled to each other.