A method for determining transmission and/or clutch parameters of a motor vehicle automatic transmission having at least one clutch, in particular for basic calibration of the transmission, in particular an automated manual transmission and/or a dual-clutch transmission, includes determining drag torque and/or kiss point of the clutch using an actuable synchronization device. The clutch has at least one drive side connected to an internal combustion engine output shaft and at least one output side connected to a transmission input shaft. The transmission output and/or drive shaft is blocked. The drive side of the clutch is driven. Basic calibration of the transmission is improved by driving the drive side of the clutch by an electric motor, providing a freewheel-shifted gear stage, and driving the drive side of the clutch by the electric motor in a rotation direction opposite the internal combustion engine output shaft.

A double clutch transmission (DCT) provides eight forward speeds and one reverse speed while minimizing the number of gear trains used for changing speed and the whole length thereof. In particular, the DCT has a simple structure using four or five gear trains and four synchro devices and is capable of providing eight forward speeds and one reverse speed while reducing the entire weight thereof. In a conventional DCT, when a gear train is added to increase the number of speed stages, the whole length thereof is increased. The provided DCT can minimize the whole length and the weight thereof, thereby reducing the manufacturing cost, the number of parts, and the fuel efficiency.

An engagement device includes: an engaged body configured to rotate in conjunction with a rotary shaft; an engaging body arranged coaxially with the engaged body and configured to engage with the engaged body by movement in an axial direction; a power source configured to provide thrust to the engaging body in the axial direction; and a hub member configured to couple the engaging body to a torque receiver which receives torque transmitted from the engaged body at a time the engaging body engages with the engaged body. The engaged body, the engaging body, and the power source are accommodated in a closed space, and the hub member is at least a part of an outer shell forming the closed space.

A shift fork shaft 123 has both end portions movably fitted in shaft supports 83e and 116a of a gear transmission 82. Clearances are left between bottom surfaces 83g and 116c of the shaft supports 83e and 116a and both end faces 123c of the shift fork shaft 123. Caps 145 are mounted in both axial ends of the shift fork shaft 123.

A shift fork shaft 123 has both end portions movably fitted in shaft supports 83e and 116a of a gear transmission 82. Clearances are left between bottom surfaces 83g and 116c of the shaft supports 83e and 116a and both end faces 123c of the shift fork shaft 123. Caps 145 are mounted in both axial ends of the shift fork shaft 123.

A motor gearbox assembly is provided for a vehicle having two wheels on opposite sides of the vehicle. The assembly includes two independent drive systems that each include an electric motor and an associated gear train, each drive system being configured to independently drive one of the wheels. The assembly further includes a common housing that receives the motors and the gear trains such that the gear trains are at least partially positioned between the motors. Furthermore, at least portions of the drive systems have generally inverse orientations in a longitudinal direction of the vehicle when the motor gearbox assembly is mounted on the vehicle.

A motor gearbox assembly is provided for a vehicle having two wheels on opposite sides of the vehicle. The assembly includes two independent drive systems that each include an electric motor and an associated gear train, each drive system being configured to independently drive one of the wheels. The assembly further includes a common housing that receives the motors and the gear trains such that the gear trains are at least partially positioned between the motors. Furthermore, at least portions of the drive systems have generally inverse orientations in a longitudinal direction of the vehicle when the motor gearbox assembly is mounted on the vehicle.

A reverse transmission system for a vehicle for engaging a reverse action on a normally forward action only engine transmission having a longitudinal orientation driveshaft output, the reverse transmission system comprising a gear rotatably connected to the longitudinal orientation driveshaft output of a normally forward action only engine transmission output; a shaft rotatably connected to the gear for transmitting power from the normally forward action only engine transmission output to the shaft; a chain sprocket connected to a chain drive and to the shaft for providing a transverse orientation output to the chain drive to change the direction of rotation of the driveshaft output, thereby for engaging the vehicle in the reverse action; and a reverse fork configured to actuate a reverse dog configured to slide upon the shaft to reversibly engage a reverse gear engaged to a first gear of the engine transmission.

Under the condition that the rotation speed of a first rotating shaft is higher than that of a second rotating shaft, supported portions go through right-handed helical flutes to perform an engaging operation. Under the condition that the rotation speed of the first rotating shaft is lower than that of the second rotating shaft, the supported portions go through left-handed helical flutes to perform the engaging operation. In a releasing operation, the supported portions go through the right-handed helical flutes to release a clutch mechanism under the condition that the rotation speed of the first rotating shaft is lower than that of the second rotating shaft, and the supported portions go through the left-handed helical flutes to release the clutch mechanism under the condition that the rotation speed of the first rotating shaft is higher than that of the second rotating shaft.

A gearbox comprising: a first shaft (2) and a second shaft (1), one of the first and second shafts being an input shaft (1) for receiving a drive torque and the other being an output shaft (2) for providing a drive torque; two intermediate shafts (6, 7) by means of which the first and second shafts (2, 1) can be coupled together, each intermediate shaft being arranged so that: (a) it can be coupled to the first shaft (2) via a respective first torque path at any of a plurality of gear ratios (1st-8th), or the respective first torque path can be disengaged; and (b) it can be coupled to the second shaft (1) via a respective second torque path, or the respective second torque path can be disengaged; and a differential torque device (50) coupled between the intermediate shafts (6, 7), the differential torque device (50) being capable of transmitting a differential torque between the intermediate shafts (6, 7).