A gear unit for a motor vehicle with a main input shaft and an auxiliary input shaft which is connected thereto via a constant gearwheel set step, wherein the constant gearwheel set step can further be connected to the output via a reverse gearwheel set step. At least one synchronized shifting clutch for connecting at least one idler gearwheel of the reverse gearwheel set step to the shaft carrying the idler gearwheel such that the idler gearwheel is fixed with respect to rotation relative to the shaft. The invention is further directed to a motor vehicle including such gear unit.

A power transmission apparatus includes a first input shaft selectively receiving an input torque, a second input shaft coaxially disposed with the first input shaft and selectively receiving the input torque, first and second intermediate shafts selectively interconnected and disposed in parallel with the first input shaft, a torque mediating shaft coaxially disposed with the first input shaft, a preliminary shifting section receiving a torque through a first input shaft and selectively outputting a shifted torque to the second intermediate shaft, a compound shifting section including a planetary gear set having a sun gear fixedly connected with the torque mediating shaft, a planet carrier fixedly connected with the second input shaft, and a ring gear externally gear-meshed with the second intermediate shaft, and an output shaft receiving a torque received from the compound shifting section and transmitting the received torque to a differential.

A differential assembly provided with a power distribution unit includes a first housing, an output shaft, a shaft, and a torque limiter. The first housing defines a biasing member bore and a brake bore. The output shaft extends at least partially through the first housing. The shaft is disposed about the output shaft and extends between a first shaft end that is connected to a differential unit and a second shaft end. The torque limiter is disposed within the first housing and is arranged to selectively inhibit rotation of at least one of the output shaft and the shaft.

A power transmission apparatus includes a first input shaft receiving an input torque, second and third input shafts coaxially disposed and selectively connected with the first input shaft, first and second torque mediating shafts coaxially disposed with the first input shaft, first and second intermediate shafts and an output shaft disposed in parallel with the first input shaft, a first shifting section receiving a torque from the third input shaft and outputting a plurality of first shifted torques, a second shifting section including a first planetary gear set selectively connected with the first input shaft and outputting a plurality of second shifted torques, and a compound shifting section forming an output torque by the input torque and the first and second shifted torques.

A control apparatus for a vehicle provided with a step-variable transmission which is disposed between drive wheels and a drive power source including at least an engine, and which is shifted by changing operating states of coupling devices, the control apparatus including an engine stability time estimating portion configured to estimate a length of stability time required for stabilization of an output state of the engine, when a determination to implement a power-on shift-down action of the step-variable transmission is made, and a control portion configured to delay a moment of generation of a shift-down command to implement the power-on shift-down action of the step-variable transmission, with respect to a moment of the determination to implement the power-on shift-down action, where the estimated length of stability time is longer than a predetermined value.

A dual clutch transmission which can reduce the overall length of a transmission and improve mountability in the vehicle by simplifying the constituent elements of the transmission, is configured by reducing the number of synchronizers and external gears and shafts, and a drive motor is not disposed on the same axle as other constituent elements to reduce the overall length of the transmission, reducing cost and weight of the transmission to improve mountability of the transmission in the vehicle.

A differential assembly provided with a power distribution unit includes a first housing, an output shaft, a shaft, and a torque limiter. The first housing defines a biasing member bore and a brake bore. The output shaft extends at least partially through the first housing. The shaft is disposed about the output shaft and extends between a first shaft end that is connected to a differential unit and a second shaft end. The torque limiter is disposed within the first housing and is arranged to selectively inhibit rotation of at least one of the output shaft and the shaft.

An actuator assembly including a fail-fix system is provided. The actuator assembly includes an output shaft, an input drive assembly, and a piston assembly. The piston assembly includes a body surrounding a piston moveable within the body. The body defines a first end and a second end opposite thereof between which the piston is moveable within the body. The piston assembly includes a spring disposed at the first end between the body and the piston. The piston assembly includes a friction mechanism disposed at the second end of the piston opposite of the first end. An adjustable area is defined within the body between the second end of the piston and the input drive assembly.

A control apparatus includes a shifting delay control portion configured to delay a moment of generation of a shift-down command to implement a power-on shift-down action of the step-variable transmission, with respect to a moment of determination to implement the power-on shift-down action, for thereby reducing a shifting shock of the step-variable transmission in the process of the power-on shift-down action. The shifting delay control portion adjusts a delay time from the moment of determination to implement the power-on shift-down action to the moment of generation of the shift-down command, on the basis of at least one of an output state of the drive power source; an inertia power required in the process of the power-on shift-down action; a consumption power to be consumed by the coupling devices; and a state of a battery to and from which an electric power is respectively supplied from and to the motor/generator.

A vehicular power unit downsized using a speed reducing mechanism of high speed reduction ratio. In a vehicular power unit, a torque applied to an input shaft from an actuator is multiplied by a speed reducing mechanism to be transmitted to an axle. The speed reducing mechanism includes: an external gear of a ring gear; a first pinion that engages with the external gear; a second pinion that rotates integrally with the first pinion; a pinion shaft that rotates integrally with the first pinion and the second pinion; a center gear that rotates integrally with a sun gear; a counter gear that engages with both of the center gear and the second pinion; and a carrier shaft that rotates integrally with a carrier. The pinion shaft is coupled to the input shaft, and the carrier shaft is coupled to the axle.