A transmission for an electric vehicle, may include a concentric deceleration device for receiving power from a motor shaft and for decelerating; an output shaft disposed in parallel with the input shaft; a hollow shaft rotatably provided on the input shaft; a clutch device provided to switch the transmission state of power from the input shaft to the hollow shaft; a first synchronizer having a hub fixed to the input shaft; a second synchronizer having a hub fixed to the hollow shaft; a plurality of driving gears having different sizes and provided on the input shaft and the hollow shaft to be engaged with at least one of the first synchronizer and the second synchronizer; and a plurality of driven gears provided on the output shaft to be engaged with the plurality of driving gears to form different shift ratios, respectively.

A gear shift control system controls an actuator so that a pushing force will be a constant gearing-phase pushing force, during a gearing phase. The gear shift control system performs control on the basis of the number of rotation of the engine in the gearing phase, which is measured at the start of the gearing phase, so that the constant gearing-phase pushing force will increase as a number of rotation of the engine in the gearing phase increases. Thus, the hitting sound due to collision between the sleeve and the shift gear in shifting gears is reduced.

An acceleration control method for a dual clutch transmission (DCT) vehicle, may include determining whether an engine speed is lower than a desired shift stage input shaft speed by a controller when a driver's demand for acceleration is verified, determining whether an engine speed increased by the demand for acceleration is equal to or greater than the desired shift stage input shaft speed by the controller, feedback-controlling an engagement-side clutch to reduce a slip caused by a difference between the engine speed and the desired shift stage input shaft speed while maintaining an engine torque by the controller when the engine speed is verified to be equal to or greater than the desired shift stage input shaft speed, and completing control by verifying whether synchronization of the engine speed with the desired shift stage input shaft speed is stabilized.

Control systems and methods for a vehicle transmission initiate a shift operation of the transmission and, during the transmission shift operation, determine an acceleration of a torque generating system output shaft based on its measured rotational speed and determine an acceleration of the transmission output shaft based on its measured rotational speed, identify an error source using a transmission model that maps differences between the determined and target accelerations back to torque generating system error and/or transmission clutch torque error and, based on the identified error source, adjust the actuation of at least some of the plurality of clutches to compensate for the torque generating system error and/or transmission clutch torque error to mitigate or eliminate noise/vibration/harshness (NVH) caused by the transmission shift operation.

An electrified vehicle includes a transmission having shiftable gears, an electric motor coupled for common therewith, and a synchronizer controllable for coupling the transmission to a driveline; friction brakes; a control system including a hybrid control unit, a brake control unit and a transmission control unit, wherein the hybrid control unit functions as a supervisory controller over the transmission control unit and the brake control unit and wherein the hybrid control unit is configured to coordinate control among the transmission control unit and brake control unit to compensate for unavailability of electric motor regeneration torque during an upcoming transmission gear shift event and blend in the friction brakes to provide a continuous and smooth deceleration of the electrified vehicle during the transmission shift event.

Disclosed is a gear shift control method of a Dual Clutch Transmission (DCT) vehicle. According to the present invention, the gear shift control method of a Dual Clutch Transmission (DCT) vehicle includes: a gear shift start determination step (step S100) of determining whether a kick down shift, which performs a gear shift to a lower gear as an acceleration pedal is handled according to an acceleration intention of a driver, is started; a biaxial shift determination step (step S200) of determining, when the kick down shift is started, whether the gear shift is a biaxial shift, in which a difference of gear level between a target gear and a current gear is as much as an odd-numbered gear level larger than one level; a clutch torque control step (step S300) of uniformly decreasing torque of a release-side clutch and uniformly increasing torque of a connection-side clutch to synchronize revolutions per minute of a target gear input shaft with increasing revolutions per minute of an engine, if a current gear state of the vehicle determined at the biaxial shift determination step is the biaxial shift; a clutch synchronization determination step (step S400) of determining whether the revolutions per minute of the target gear input shaft is synchronized with the revolutions per minute of the engine by the clutch torque control; and a gear shift performing step (step S500) of performing gear shift control for engaging the target gear, when the revolutions per minute of the target gear input shaft is synchronized with the revolutions per minute of the engine.

A drive system is provided with a first motor generator as a power source, and a multistage gear transmission for changing the speed of output from the first motor generator and transmitting the output to drive wheels. The multistage gear transmission has a plurality of engagement clutches as shifting elements that are meshingly engaged upon movement from a disengaged position. This hybrid vehicle is provided with a start control device where, when a start clutch has been engaged while the vehicle is stopped, the start control device maintains the engagement of the start clutch for a duration that includes when the vehicle is stopped and until the next vehicle start.

A system, method and apparatus are disclosed for a clutch assembly for an automated manual transmission. The clutch assembly includes a dual power path. One power path connects a prime mover to the automated manual transmission via a wet clutch, and a second power path connects one of the prime mover and the automated manual transmission to a grounded connection for synchronizing the speed thereof for a gear change.

A dual clutch transmission for a motor vehicle including two sub-transmissions, each having at least one input shaft. An output shaft outputs drive from both sub-transmissions. The input shafts are arranged on an input shaft axis and the output shaft is arranged on the input shaft axis or a parallel countershaft axis. An intermediate gear system includes at least one countershaft which is arranged on the countershaft axis. At least four shifting elements are arranged such that, in each case, at least two shifting elements are arranged on the input shaft axis and on the countershaft axis. At least one input shaft can be connected to the output shaft by way of two wheel planes and/or at least one shifting element. Preferably half of the shifting elements are unsynchronized and at least one-third of the shifting elements are synchronized. Also a method for operating a dual clutch transmission.

A transmission system (8) comprising at least one floating gear (14a, 16a, 18a) rotationally mounted upon a first shaft the system comprising a floating gear activation system for controlling torque transfer between the at least one floating gear (14a, 16a, 18a) and the first shaft (10), the gear activation system comprising a first device (28, 30) having a friction interface (28) for frictional engagement with a friction interface (30) disposed on a first side of the at least one floating gear (18a), and a second device (25, 26) having a locking interface (25) for an interpositional engagement with a locking interface (26) disposed on a second side, opposing the first side, of the at least one floating gear (18a), whereby the floating gear (18a) is rotationally coupleable to the first shaft (10) by the friction interface (28/30) and/or the locking interface (25/26).