This invention pertains to the field of power transmission. Machines using a power transmission mechanism for transmission of the mechanical power produced by a source (engine (2), electric motor, pneumatic and hydraulic pump) to another component of the machine (wheel (21), electric motor, electric generator, pneumatic and hydraulic pump) through multiple transmission paths (different gear ratios (14), (15)) are subjects of this invention. It is disclosed that control of a switching from one power transmission path to another is done in a manner involving simultaneous load transfer and speed synchronization rather than sequential performance of these two functions, and the resulting method developed in the invention leads to switching operations that produce less disturbance at the input of the said component. The said method is applied to the problem of controlling gearshifts in automatic transmissions of ground vehicles.

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.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets controls the shift actuator with actuating and opposing pulses, and interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A shift control system that reduces drop in driving force and shocks during execution of clutch-to-clutch upshifting is provided. The control system is configured to reduce a torque transmitting capacity of a first clutch at a predetermined rate while increasing a torque transmitting capacity of a second clutch with a reduction in the torque transmitting capacity of the first clutch during execution of the upshifting, to set a target speed of the engine to a level determined by adding a predetermined speed to a synchronous engine speed corresponding to a low speed stage, during a torque phase in which the torque transmitting capacity of the first clutch is being reduced and the torque transmitting capacity of the second clutch is being increased, and to execute a feedback control of an engine torque in such a manner as to maintain the engine speed to the target speed based on a difference between the target speed and an actual engine speed.

A clutch disengagement position is detectable with high precision even during speed change. A vehicle transmission device can include a transmission including a main shaft to which rotational power from an engine is inputted via a clutch, and a countershaft, a clutch operation member that is driven by an actuator and performs disengaging and engaging operations of the clutch, and a driving wheel to which rotational power of the countershaft is transmitted via a driving force transmitting device. A damper member deformed by a driving force is provided in the countershaft, the driving force transmitting device or the driving wheel, or among the countershaft, the driving force transmitting device and the driving wheel. A control device learns a clutch disengagement operation amount when the control device detects deceleration of a predetermined value of the rotational frequency of the main shaft.

The present disclosure provides a shift control method for a hybrid vehicle with a DCT that includes: a shifting state-determining step in which a controller determines whether an inertia phase of power-off down-shift is entered; a motor torque-adjusting step that request to reduce regenerative braking torque of a motor as much as a predetermined requested reduction amount, when the controller determines that the inertia phase has been entered in the shifting state-determining step; and a clutch torque-reducing step that ends the motor torque-adjusting step and reduces torque of an engagement clutch, when the requested reduction amount of the regenerative braking torque of the motor is less than zero while the controller performs the motor torque-adjusting step.

A clutch burst prevention method for preventing a non-drive input shaft clutch of a vehicle provided with a double clutch transmission (DCT) from damage may include a torque reduction operation of reducing a torque of an engine by an ECU when a stuck phenomenon occurs on a shift gear of the non-drive input shaft.

A shift control system that reduces drop in driving force and shocks during execution of clutch-to-clutch upshifting is provided. The control system is configured to reduce a torque transmitting capacity of a first clutch at a predetermined rate while increasing a torque transmitting capacity of a second clutch with a reduction in the torque transmitting capacity of the first clutch during execution of the upshifting, to set a target speed of the engine to a level determined by adding a predetermined speed to a synchronous engine speed corresponding to a low speed stage, during a torque phase in which the torque transmitting capacity of the first clutch is being reduced and the torque transmitting capacity of the second clutch is being increased, and to execute a feedback control of an engine torque in such a manner as to maintain the engine speed to the target speed based on a difference between the target speed and an actual engine speed.