The invention relates to a power split gearbox for a motor vehicle. The power split gearbox comprises a drive shaft which can be connected to an internal combustion engine in order to feed in torque, a first mechanical branch with a planetary gear mechanism arrangement, an infinitely variable second branch which can be connected to the first branch and comprises two adjustable energy converters which can be coupled to one another in energy terms and can be operated in each case in both directions, and at least one output shaft which can be coupled to the drive shaft via the first and the second branch. At least one first reversing stage is provided between the drive shaft and the output shaft for changing between at least one first forward driving range and at least one first reverse driving range, wherein the reversing stage either reverses or keeps constant all of the rotational directions of the sun gears, the internal gear and the spider shaft during changing between the first forward driving range and the first reverse driving range.

A control process including the following steps is executed. The control process includes, at the time of switching from series-parallel mode to series mode, a step of reducing an engine torque, a step of releasing a clutch, a step of reducing a reaction torque of a first rotary electric machine and a step of increasing a torque of a second rotary electric machine, and, when synchronization is started and a step of increasing a positive torque of the first MG, a step of starting engagement of a clutch, and, when a rotation speed of the first rotary electric machine and a rotation speed of an engine are synchronous with each other, a step of engaging the clutch.

A drive system for a vehicle includes a first planetary device, a second planetary device directly coupled to the first planetary device, a first electromagnetic device at least selectively coupled to the first planetary device and including a first shaft, a second electromagnetic device directly coupled to the second planetary device and including a second shaft, and an output shaft coupled to the first planetary device. The first shaft and the second shaft are radially aligned with the first planetary device and the second planetary device. The output shaft is radially aligned with the first planetary device and the second planetary device.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

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.

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 variable drive system of a power system is disclosed. The variable drive system may include an engine gearset to transfer power from an engine output of an engine to a variable input driveshaft of the variable drive system. The variable drive system may include a generator gearset to transfer power, generated by the engine, to a generator driveshaft of a generator. The variable drive system may include a variable drive, coupled to the variable input driveshaft, to enable a gear ratio between engine output and the generator driveshaft to be adjustable, the variable input driveshaft being offset from at least one of the engine output or the generator driveshaft. The variable drive system may include a direct drive clutch to bypass variable power transfer through the variable drive and enable direct power transfer from the engine output to the generator driveshaft.

A powershift transmission includes an input shaft, an output shaft arranged parallel with the input shaft, a branching unit arranged on the input shaft through which a torque acting on the input shaft is divided between two power paths, a switch group including at least two switching stages arranged in the first power path, and a torque converter arranged in the second power path. A torque is transmitted from the input shaft to the output shaft via the switch group and the torque converter.

The invention relates to a power split transmission (1) and a method of merging the power flows of the power split transmission (1). A power input shaft (2) drives a planetary gear set (10) splitting the input power into a power flow over a variable power branch (20) and into a power flow over a mechanical power branch (30). The power flow transmitted over the variable power branch (20) can be merged again with the power flow over the mechanical power branch (30) for driving a power take-off shaft (3). A reverser (8) comprising a first clutch (4), a second clutch (5), a first gear set (6) and a second gear set (7) is used for merging the power flows and for driving the power take-off shaft (3). By engaging the first clutch (4) and disengaging the second clutch (5) the first gear set (6) is driven, if an output shaft (22) of the variable power branch (20) and a mechanical transmission shaft (32) are counterrotating. By engaging the second clutch (5) and the first clutch (4) disengaging the second gear set (7) is driven, if the output shaft (22) of the variable power branch (20) and the mechanical transmission shaft (32) are co-rotating, whereby the transmission ratio of the second gear set (7) is opposite to the transmission ratio of the first gear set (6).