A control method is provided for controlling a declutching of a sliding gear of a vehicle gearbox having dogs. The sliding gear rotates with a shaft of the vehicle gearbox on which the sliding gear moves axially between a declutched position and an engaged position to transmit rotation to a vehicle wheel. The control method comprises applying a zero torque request to all power sources of the vehicle, applying a declutching instruction to the sliding gear, estimating a resistance torque on the dogs in absence of rapid declutching, calculating a residual torque on the dogs as a function of a calculated resistance torque and an anti-disengagement angle of the resistance torque on the dogs, cancelling the residual torque by application of two opposing cancellation torques on the sliding gear, and declutching the sliding gear.

The present application relates to a dual mass dog collar 1 of a dog clutch, to a dual mass dog hub 3 of a dog clutch, to a power transmission system (gearbox) 2 and to a method to operate said power transmission system, comprising at least one dual mass dog collar 1 and/or at least one dual mass dog hub 3.

A method and system for operating a vehicle that includes a driveline disconnect clutch and a step-ratio transmission is described. In one example, the method includes shifting the step-ratio transmission to neutral and accelerating an engine to an expected input shaft speed of the step-ratio transmission via applying full output capacity of an electric machine to the engine.

An electric driveline comprising an electric drive motor and a transmission, and a method of shifting gears therefor. The transmission comprises an output shaft, a synchronizer, preferably a hydraulically actuatable synchronizer, for selectively drivingly engaging the electric drive motor with the output shaft via either one of a first gear providing a first gear ratio .sub.1 between the electric drive motor and the output shaft, and a second gear providing a second gear ratio .sub.2 between the electric drive motor and the output shaft, and an electronic shift controller for controlling a gear shift from the first gear to the second gear. The electronic shift controller is configured to actuate the synchronizer to disengage the first gear and to engage the second gear, and to synchronize a motor speed of the electric drive motor with a target speed.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

Systems and methods for performing a garage shift of an automatic transmission of a vehicle comprise maintaining a clutch at a first holding pressure while the transmission is in a neutral gear and a brake input signal satisfies a threshold and maintaining the clutch at a lower second holding pressure while the transmission is in the neutral gear and the brake input signal satisfies the threshold to mitigate or eliminate causing drive torque to be transferred from a torque generating system of the vehicle to its driveline via the transmission. When the brake input signal satisfies the threshold and a shift from the neutral gear to a non-neutral gear is requested, the garage shift is then executed.

A transmission system for a vehicle has a shift driving mechanism which operates, under control by a control unit, at the time of shifting the gear position, to disengage a transmission gear of a current gear position and a shifter from each other after engaging a transmission gear of a next gear position and a shifter with each other in a condition where a transmission clutch that transmits power to the transmission gear of the next gear position is in an engaged state. This ensures smoother and swifter shifting of gear position.

A method is provided for disengaging a tooth clutch of an inactive gear in a dual clutch transmission during vehicle acceleration or retardation. The dual clutch transmission includes an engaged active gear through which torque is transmitted between an engine and driven wheels, an engaged inactive gear to be disengaged, and an electric motor drivingly connected to a shaft of the inactive gear. The method includes controlling the electric motor to provide a compensational torque for temporarily decreasing or substantially eliminating torque transferred by the tooth clutch of the inactive gear, and disengaging the engaged inactive gear. The disclosure also concerns a corresponding dual clutch transmission, a computer program, a computer readable medium, and an electronic control unit for controlling the electric motor of a dual clutch transmission.

A method controls a shift actuator with a sliding gear for a gearbox. The gearbox includes a control element for controlling a shift fork responsible for disengaging and engaging pinions on a shaft of the gearbox that receives torque from a traction machine powered by the on-board electrical system of the vehicle. The control element is positioned upstream of a mechanical spring-assist system and regulated in position by a DC actuating motor. The method includes temporarily raising a supply voltage applied to the actuating motor above a base voltage of an on-board electrical system during the disengaging and engaging the pinions.

The transmission (10) comprises a support (40) where an input central shaft (1) is rotatably supported. A central wheel (11) is integral with the central shaft (1) and rotates therewith. The transmission further comprises an output wheel (18) and a rotary unit (100) rotatably supported by the support (40) around a rotation axis (100) to take a plurality of angular positions. Selectable gear pairs (101-109) are rotatably supported on the rotary unit (100). A rotation mechanism of the rotary unit (100) brings the rotary unit (100) into one of said angular position selectively. In each angular position of the rotary unit (100) a selectable gear pair (101-109) transmits motion from the central wheel (11) to the output wheel (18);