A method is provided for controlling a gear shift from a forward gear to a reverse gear in a transmission arrangement, the method including the steps of: positioning a first locking mechanism and a first connecting mechanism at least in a partially engaged state for reducing a rotational speed of a planet carrier of a second planetary gear set; and positioning a second locking mechanism in an engaged state when a rotational speed of the planet carrier of the second planetary gear set is below a predetermined threshold limit.

A method of synchronizing the countershaft speed, in the direct gear, for a hybrid application. The transmission (1) comprises a main transmission (HG) comprising two parallel partial transmissions with at least one countershaft (VW), an output shaft (3), and two planetary transmissions (PG1, PG2) each comprising a carrier (ST1, ST2), sun gear (SR1, SR2) and ring gear (HR1, HR2). Each partial transmission has a transmission input shaft (4, 5), with a hollow first input shaft (4) and the solid second input shaft (5). The first planetary transmission (PG1) connects as a range group to the main transmission (HG). The main transmission (HG) comprises first (R1), second (R2), third (R3), fourth (R4) and fifth gear planes (R5) and first (S1), second (S2), third (S3) and fourth shift elements (S4). Synchronization of the countershaft speed to a target speed, in direct gear, is performed via speed control of the electric machine (2).

A power transmission apparatus may include engine; first motor/generator; first rotation element fixed to the engine, second rotation element fixed to the first motor/generator, and third rotation element; first input shaft selectively connectable to the third rotation element; second input shaft selectively connectable to the third rotation element; third input shaft; an output shaft; an idle shaft operably connected to the second input shaft and the third input shaft; and speed stage module including drive gears rotatably disposed on the first input shaft, the third input shaft, or the idle shaft, driven gears meshed with the drive gears and fixed on the output shaft, and power delivery gears and an idle gear fixed on the second input shaft, the third input shaft, or the idle shaft, and synchronizers selectively connecting at least one among the drive gears to the first input shaft, the third input shaft, or the idle shaft.

A transmission arrangement for a vehicle includes a first, a second, a third, and a fourth planetary gear set including a sun gear, a planet carrier and a ring gear, respectively, wherein the transmission arrangement further includes a transmission housing, an input shaft and an output shaft, wherein two of the sun gear, the planet carrier and the ring gear of the fourth planetary gear set are each operatively connected to a respective one of the input shaft, the sun gear, the planet carrier and the ring gear of the third planetary gear set.

Methods and systems for a multi-ratio gear box and a countershaft power-shift transmission are provided. The system contains one or more electric motors coupled to a transmission housing in such that the electric motor does not exceed the highest point of the transmission. A first shaft may be coupled to one or more input speed reduction gear sets. A second shaft may be coupled to a multi-range clutch allowing two speeds. A third shaft may be coupled to a low-speed clutch and a fourth shaft may be coupled to a high-speed clutch, together doubling the number of speeds. The high and low speed clutches provide a large gear spread that allow the twin range clutches to have a reduced gear spread, overall reducing the required size of the transmission system.

A powershift transmission has a split group with a plurality of powershift stages and an input shaft that can be rotatably driven by a drive shaft of a motorized drive. The input shaft transmits in a stepped-up manner to an output shaft of the split group a rotational movement corresponding to a selected powershiftable stage transmission. A synchromesh transmission group has at least four gear stages and can be rotatably driven by the output shaft of the split group via an intermediate group located therebetween, and via the output shaft of the synchromesh transmission group an axle transmission of the motor vehicle can be rotatably driven. The intermediate group has first and second switching elements each having an output shaft that can be coupled by means of a switchable clutch to an idler. First and second output gears are arranged on the output shaft of the synchromesh transmission group.

A multiple speed transmission includes an input shaft, an output shaft, a first planetary gearset having a first member, a second member, and a third member, and a second planetary gearset having an input member, a reaction member, a second member, and a third member. The transmission also includes a plurality of interconnecting members each connected between at least one of the first and second planetary gearsets and at least another of the first and second planetary gearsets. The transmission includes a plurality of torque-transmitting mechanisms which are selectively engageable in combinations of at least two to establish a plurality of forward speed ratios and a plurality of reverse speed ratios between the input shaft and the output shaft.

A transmission for a vehicle, including an input shaft, a main shaft, and a countershaft, the main shaft being coaxial with the input shaft and the countershaft being parallel therewith, first and second primary gear planes arranged for torque transfer between the input shaft and the countershaft, at least one secondary gear plane arranged for torque transfer between the countershaft and the main shaft. The transmission further includes a reverse shaft arranged in parallel with the main shaft, wherein the first primary gear plane comprises a first reverse shaft gearwheel arranged on the reverse shaft, and wherein the second primary gear plane comprises a second reverse shaft gearwheel arranged on the reverse shaft, the second reverse shaft gearwheel being selectively rotationally connectable to the first reverse shaft gearwheel so as to engage a reverse gear of the transmission.

A transmission having a main transmission and a splitter group, and including at least four spur gear planes formed with a countershaft and at least five shifting elements for engaging at least six gears between the transmission input and output shafts. When shifting between gears with the highest and the second-highest gear ratios, a shift occurs in the shifting elements associated with the splitter group but not in the shifting elements associated with the main transmission, whereas when shifting between gears with the lowest and second-lowest gear ratios, a shift occurs in the shifting elements associated with the main transmission but not in the shifting elements associated with the splitter group. An electric machine can be connected by a gearset, and depending on its shift position, the gearset acts as a pre-transmission ratio for the electric machine or as a superimposition transmission.

A group transmission device includes an upshift assembly with a first transmission element, a second transmission element and a third transmission element. A downshift assembly has a first transmission element, a second transmission element and a third transmission element. A main shaft is arranged coaxially to the upshift assembly and a layshaft is arranged parallel to the main shaft. A first idler gear is arranged coaxially to the main shaft and axially between the upshift assembly and the downshift assembly and is connectable to the main shaft for conjoint rotation by a first shift unit. The first idler gear is connectable to the third transmission element of the downshift assembly for conjoint rotation by a second shift unit.