Packaged boost systems and electrical assist assemblies presented. In one example, packaged boost system includes a supercharger, a brake assembly, and a transmission assembly that are packaged together in a generally axisymmetric configuration. In one example, a packaged electrical assist assembly includes a supercharger, a transmission assembly, and a brake assembly that are packaged together in a generally axisymmetric configuration.

A powertrain for a vehicle includes a housing, a motor generator unit, a torque converter, a first and second shafts, a first and second gear sets, and a torque transmitting mechanism. The motor generator unit includes an output member. The torque converter includes a pump and a turbine. The pump is connected for common rotation with the output member of the motor generator unit. The first shaft rotatably is supported by the powertrain housing and is connected for common rotation with the turbine of the torque converter. The second shaft is rotatably supported by the powertrain housing and disposed parallel to the first shaft. An output gear is connected for common rotation to the second shaft.

A reversible torque transfer device includes an input shaft including a center disc, an output shaft including a first output gear and a second output gear, a first outer disc on a first side of the center disc, and a second outer disc on a second side. The first outer disc concentrically surrounds the input shaft and is configured to move translationally along the input shaft and rotate a first input gear, the first input gear being mechanically connected to the first output gear. The second outer disc concentrically surrounds the input shaft and is configured to move translationally along the input shaft and rotate a second input gear, the second input gear being mechanically connected to the second output gear. The center disc drives a rotational movement of the first and second outer discs based on a translational position of the outer discs along the input shaft.

A rotational drive unit having an input rotatable about a first axis of rotation and configured to be driven by a power source in a single rotational direction. The rotational drive unit including a first shaft in operable communication with the input and configured to rotate in a first direction, a second shaft in operable communication with the input and configured to rotate in a second direction opposite the first direction, an output rotatable about a second axis of rotation, and a clutch assembly in operable communication with the first shaft, the second shaft, and the output. Where the clutch assembly is operable in a first configuration in which force is transmitted between the first shaft and the output, and a second configuration in which force is transmitted between the second shaft and the output.

A transmission that reduces the difference of rotational speed when engaging a main shaft-side sprocket and a main shaft-outer shaft, in a low-speed traveling mode. When shifting from first gear to neutral in the transmission, a dog on a drive gear is engaged with a dog hole in a main shaft-side sprocket, engagement between a dog on a driven gear for first gear and a dog hole in a driven gear is released, and then a first clutch and a second clutch are disconnected with the drive gear and the main shaft-side sprocket being engaged.

Packaged boost systems and electrical assist assemblies presented. In one example, packaged boost system includes a supercharger, a brake assembly, and a transmission assembly that are packaged together in a generally axisymmetric configuration. In one example, a packaged electrical assist assembly includes a supercharger, a transmission assembly, and a brake assembly that are packaged together in a generally axisymmetric configuration.

A gear mechanism for increasing torque includes: an input shaft; at least one intermediate shaft; where the at least one intermediate shaft is parallel to and offset from the input shaft; at least one force transmitting member connecting the input shaft and the at least one intermediate shaft; where the at least one force transmitting member is configured for rotating the at least one intermediate shaft in the same direction as the input shaft. The at least one intermediate shaft is mated with at least one fixed mating member and is rotatably connected to a rotatable support member. The support member is rotatable about the input shaft and connected to an output shaft.

A main shaft side sprocket wheel and a countershaft side sprocket wheel are provided for relative rotation on the shafts with a chain wrapped around and extended between the sprocket wheels. One of the driven gears is a floating gear provided for relative rotation on the countershaft. The countershaft side sprocket wheel is provided for integral rotation with the floating gear. The main shaft includes a main shaft inner shaft which includes the main shaft side sprocket wheel, and an outer pipe disposed coaxially on the outer side of the main shaft inner shaft in a diametrical direction and capable of being placed into and out of integral rotation with the main shaft side sprocket wheel. A reverse transmission gear for meshing with a driven gear is provided on the outer pipe. A reduction gear ratio by the floating gear or the reverse transmission gear is set higher than 1.