Abstract: A control apparatus for an automatic transmission including a hydraulic pressure control means for controlling supply of hydraulic pressure to a first friction engagement element and a second friction engagement element and discharge of hydraulic pressure from the first friction engagement element and the second friction engagement, and a discharge rate changeover control means for increasing a discharge rate value of the hydraulic pressure which is discharged from the first friction engagement element in a case where when shifting from one of operating ranges to the other thereof is selected, changeover to the other operating range is carried out before completing release of the first friction engagement element, so as to become larger than a discharge rate value of the hydraulic pressure which is discharged from the first friction engagement element before the changeover to the other operating range is carried out.

Abstract: A construction vehicle includes a control unit configured to shift gear after performing pre-shifting to couple a target speed-change gear that corresponds to a target speed with a target speed-change shaft in non-transmitting state of rotation of the input shaft when the gear shift is performed from a current speed to the target speed, in a state in which the current speed gear that corresponds to the current speed step and the current speed-change shaft that corresponds to the current speed gear are coupled. When the vehicle speed detected by the vehicle speed detecting section is zero, the control unit is configured to perform pre-shift auxiliary control prior to the pre-shifting control to input the rotation of the input shaft to the target speed-change shaft in a state in which the target speed-change shaft is not coupled to the plurality of speed-change gears.

Abstract: Method and arrangement for providing an electronic gear shift selector associated with an automatic mechanical transmission for a heavy vehicle. The gear shift selector includes a toggle switch for asserting at least one gear shift request, a counter receiving the at least one gear shift request, and a time delay for preventing communication of the at least one gear shift request from the counter until a predefined time period has passed. A method for communicating a collective gear shift request to a gear box includes asserting one or more gear shift requests with a gear shift selector, communicating the gear shift requests to a counter, determining the collective gear shift requests occurring within a predefined time period, communicating the gear shift requests occurring within the predefined time period to a gearbox.

Abstract: A system and method for selectively engaging and disengaging auxiliary equipment to avoid gear clash in a vehicle is disclosed. The system includes a transmission, a transfer case, and a transmission controller. The transmission has a plurality of gears for establishing a plurality of gear ratios. The transfer case is coupled to the transmission by an output shaft. The transmission controller is in communication with a plurality of control devices for controlling the operation of the transmission. The controller includes control logic for controlling the engagement and disengagement of the auxiliary equipment.

Abstract: A dual clutch transmission includes odd-numbered forward traveling speed drive trains to be activated by engaging a first clutch, even-numbered forward traveling speed drive trains to be activated by engaging a second clutch, and a plurality of backward traveling speed drive trains including at least one backward traveling train to be activated by engaging either the first or second clutch. While a reverse mode is set and when a reverser operation means is shifted between a forward traveling position and a backward traveling position, the first and second clutches are alternately engaged/disengaged for a forward/backward traveling speed shift between a backward traveling speed set by at least one backward traveling speed drive train and a forward traveling speed set by any one forward traveling speed drive train activated by engaging the first or second clutch which is different from the first or second clutch adapted to be engaged for activating the at least one backward traveling speed drive train.

Abstract: A method of engaging a clutch within a drive train may include detecting a fault in a clutch engagement data link, selecting an alternative clutch control logic, detecting a value indicative of a rotational speed of a first portion of the clutch and moving a second portion of the clutch based upon the detected value.

Abstract: A clutch control may include a starting clutch that is disposed at a rear portion of an engine, an automatic transmission that is disposed at a rear portion of the starting clutch and uses a shifting element to vary a rotation ratio between an input shaft and an output shaft thereof, a driving wheel that receives a torque of the engine through the starting clutch and the automatic transmission to move a vehicle, and a control portion that combinatively slips the starting clutch and the shifting element. Accordingly, the starting clutch and the shifting element (clutch element or brake element) of the transmission are combinatively slip-controlled such that the friction energy is reduced, and the durability and the transmission efficiency are improved.

Abstract: A method for improving starting of an engine that may be repeatedly stopped and started is presented. In one embodiment, the method adjusts a transmission tie-up force in response to engine starting. The method may improve vehicle launch for stop/start vehicles.

Abstract: A method for improving starting of an engine that may be repeatedly stopped and started is presented. In one embodiment, the method adjusts a transmission actuator in response to engine combustion during an engine start. The method may improve vehicle launch for stop/start vehicles.

Abstract: A method for controlling a torque direction transition in a dual clutch transmission includes decreasing a torque capacity of a transmission input clutch when clutch slip reaches a target slip during a power-off condition, producing a subsequent power-on condition, and increasing torque capacity of said clutch when clutch slip reaches a second target slip.

Abstract: A shift-by-speech transmission system with intelligent shifting algorithm allows a driver or a motorcyclist to choose a desired gear by voice command. An intuitive and engaging shift-by-speech technology disclosed in the present invention, called “VoiceShift”, allows the driver or the motorcyclist to switch gears by voice commands. VoiceShift also allows the driver or the motorcyclist to skip-shift gears in non-sequential manner, thereby giving the driver a sense of freedom and excitement similar to a stick-shift manual transmission vehicle. A novel intelligent shifting algorithm of the shift-by-speech transmission system is capable of auto-correcting the driver's judgment error in skip-shifting by engaging a closest mechanically-safe gear to the driver's desired gear issued via voice command.

Abstract: A twin clutch type speed change control system changes over the gear position by switching between a pair of clutches, to reduce the collision sound generated between a free gear and a slide member at the time of changeover of the gear position. In the twin clutch type speed change control system designed to perform gear position changeovers between odd-ordinal gear positions and even-ordinal gear positions through a process in which an engaged clutch is disengaged whereas a disengaged clutch is engaged, the formerly disengaged clutch is supplied with a minute oil pressure P1 toward the clutch engaging side and is thereby preliminarily moved by a minute amount toward the clutch engaging side, at the time of changeover of the gear position.

Abstract: A system and method for providing TCC control and/or transmission gear shift control by considering the rate of change of the accelerator pedal or throttle position. The method determines whether the rate of change of the throttle position exceeds a predetermined positive rate of change or a predetermined negative rate of change and, if so, releases the TCC to provide TCC control. Alternatively, or additionally, the method can provide a transmission gear down-shift or up-shift depending on which direction the throttle position is changing. Once the TCC and/or gear shift control has been initiated, the method can start a timer and then return to normal TCC and/or gear shift control after the timer has expired. The TCC and/or gear shift control can also return to normal if the rate of change of the throttle position indicates that the throttle is being returned to its previous position.

Abstract: A work machine includes an internal combustion (IC) engine, and an infinitely variable transmission (IVT) coupled with the IC engine. The IVT includes an adjustable module and a mechanical module, with an adjustable input/output (I/O) ratio. A clutch is coupled with the mechanical module and has an output. An adjustable operator input device provides an output signal representing a power limit control. At least one electrical processing circuit is coupled with the operator input device and configured for controlling a selected combination of the I/O ratio and the clutch output, dependent upon the output signal from the operator input device.

Abstract: The present invention comprehends a plurality of embodiments of a hydraulic control system for various configurations of dual clutch transmissions. The hydraulic control systems all include a regulated source of pressurized hydraulic fluid including an electric pump, a filter and an accumulator, a pair of pressure control valves and a branching hydraulic circuit including pressure or flow control valves, spool or logic valves and two position valves which collectively supply and exhaust hydraulic fluid from a plurality of shift actuators. The actuators are connected to shift rails which include shift forks and are slidable to engage synchronizers and positive clutches associated with the various gear ratios.

Abstract: An ECU executes a program including a step of detecting a running speed of a vehicle and a current gear stage of the vehicle, a step of determining whether or not shifting is required, a step of calculating a required period T(D) for performing double clutch control if shifting is required, a step of calculating a required period T(S) for synchro-rotational synchronization, a step of determining whether or not the required period T(D) for double clutch control is equal to or shorter than the required period T(S) for synchro-rotational synchronization, and a step of carrying out shifting by performing double clutch control if the required period T(D) for double clutch control is equal to or shorter than the required period T(S) for synchro-rotational synchronization. A sense of incongruity felt by a driver during shifting is thereby suppressed.

Abstract: A device for reducing the drop in tractive force during the gear shifting phase of an automatic transmission (1) comprising an automatically actuated drive clutch is proposed that comprises a rotary storage device (8) that, if necessary, can be coupled in a friction lock by means of two transmission ratio steps (4, 5) that are each assigned a friction clutch (6, 7) to the output shaft (3) of the transmission (1) or, if the transmission has a downstream range group, to the output shaft of the main friction transmission as needed, wherein one of the two friction clutches (6, 7) can be activated at any time, and wherein a step up ratio can be achieved and the rotary storage device can be loaded with one of the transmission ratio steps (5), whereas a step down ratio can be achieved and energy can be released from the rotary storage device (8) to the output shaft (3) using the other transmission ratio step (4).

Abstract: A method for operating a semi-automatic or automatic mechanical transmission of a heavy truck when driving at idle speed is provided. The method includes supplying fuel to the engine of the heavy truck at a rate that facilitates engine-idle operation. In another step, the method engages the automatic or semi-automatic transmission in a gear higher than the starting gear of the transmission and permits the truck to operate at a first substantially uniform driving velocity under engine-idle power. Depending upon traffic and environmental requirements which require a higher speed, the driver upshifts the semi-automatic or automatic transmission by depressing a control device for manual gear selection arranged on a gear shift lever of the truck and then drives the truck at a second substantially uniform driving velocity under engine-idle power. The second substantially uniform driving velocity is greater than the first substantially uniform driving velocity.

Abstract: A lock-up clutch control apparatus for controlling a lock-up clutch (6) provided in a torque converter (5) installed between an engine (3) and a transmission (4), is disclosed. The lock-up clutch control apparatus has a differential pressure generator (7,8) which engages, causes a slip of or disengages the lock-up clutch by adjusting the differential pressure supplied to the lock-up clutch (6); a sensor (11/15) for detecting a rotational speed of the engine; a sensor (16) for detecting an input rotational speed to the transmission; and a controller (1). The controller (1) conducts proportional integration control by using a command signal to the differential pressure generator (7,8), so that an actual slip rotational speed, which is the difference between the engine rotational speed (Np) and input rotational speed (Ni) to the transmission, becomes a target slip rotational speed (Nt).

Abstract: A transmission control unit predicts a next gear position when a predetermined gear position is achieved. In accordance with a result of the prediction, the transmission control unit operates a predetermined synchromesh to execute a standby control (pre-shift control). In the standby control, a transmission input shaft connected to a friction transfer mechanism not used for achieving a current gear position and a transmission output shaft are connected to each other via a predetermined gear train, and made standby. The transmission control unit makes different from each other an engagement load of the synchromesh when a connection of the synchromesh is done in accordance with the prediction result and an engagement load of the synchromesh when a connection of the synchromesh is done in accordance with the other condition different from the prediction result.

Abstract: A control system for a power transmission unit of a vehicle transmitting power outputted from a prime mover is disclosed. The control system includes a resonance detecting/predicting device which detects or predicts a generation of a resonance of the power transmission unit resulting from a power transmission; a driving condition detecting device which detects a driving condition of a vehicle in case the generation of a resonance is detected or predicted by the resonance detecting/predicting device; and a resonance dampening control selecting device which selects a control for dampening the detected or predicted resonance on the basis of the driving condition of the vehicle detected by the driving condition detecting device.

Abstract: A vehicle driveline control system includes monitoring when the transmission is in gear and the clutch is left open. If that condition exists for a selected amount of time, the controller provides an indication to the driver regarding the open clutch status. In one example, the controller alters the RPM rate of the engine to provide audible feedback to the driver. For example, the controller raises the engine RPM rate from an idle rate to a higher rate to simulate what the driver hears upon vehicle launch. A variety of indicators and control strategies may be used with a system designed according to this invention.

Abstract: A method for operation of a drivetrain including a drive motor and an automatic transmission having at least five shift elements, of which, at least three shift elements are engaged in each forward and reverse gear and the other shift elements are disengaged. Two successive shifts are accomplished by two overlapped single gear shifts such that a) during the first shift, a first shift element is engaged or disengaged while a second shift element is disengaged or engaged; b) during the first shift, second and third shift elements are prepared for either engagement or disengagement, and c) during the first and the second shifts at least one fourth shift element is kept engaged or nearly engaged.

Abstract: A method for determination of the synchronization point of an automatic double clutch transmission comprising two component transmissions each with one input shaft that connects via a friction clutch to the drive shaft of a motor and several gears, each shifted via a friction-synchronized gear clutch. The method includes the steps of selecting the gear clutch of a gear of a momentarily load-free component transmission; moving the associated gear setter to the neutral position as needed; successive movement of the associated gear setter in the direction of the shifting position of the selected gear until synchronous running is attained on the gear clutch within an applicable threshold; determination of the current synchronization point of the gear clutch from the current adjustment parameter of the associated gear setter; and adaptation of the valid synchronization point of the gear clutch to the current synchronization point.

Abstract: A method and system for executing a shift from a first fixed gear to a second fixed gear in a powertrain system comprising a two-mode, compound-split, electro-mechanical transmission operative to receive a speed input from an engine is described. It includes deactivating an off-going clutch, and generating a time-based profile for rotational speed of an oncoming clutch. The input speed is controlled based upon the rotational speed of the oncoming clutch and an output of the transmission. The oncoming clutch is actuated, preferably when the input speed is synchronized with a rotational speed of an output shaft of the transmission multiplied by a gear ratio of the second fixed gear, preferably after a predetermined elapsed period of time in the range of 500 milliseconds.

Abstract: A system and method for selectively engaging and disengaging auxiliary equipment to avoid gear clash in a vehicle is disclosed. The system includes a transmission, a transfer case, and a transmission controller. The transmission has a plurality of gears for establishing a plurality of gear ratios. The transfer case is coupled to the transmission by an output shaft. The transmission controller is in communication with a plurality of control devices for controlling the operation of the transmission. The controller includes control logic for controlling the engagement and disengagement of the auxiliary equipment.

Abstract: A drive unit for a motor vehicle, comprising an engine, a transmission or gearbox, a clutch aggregate for transmitting torque, the clutch aggregate including at least two friction clutches that are assigned to an input shaft of the transmission or gearbox, wherein at least one of the at least two friction clutches features an energy accumulator operatively arranged to generate a lock-up force required for torque transmission through the clutch aggregate, and a control unit operatively arranged to control an automatic activation of the at least two friction clutches and the transmission or gearbox, wherein in the event of a malfunction of the activation of the friction clutch, the stored energy in the accumulator creates an interruption of torque transmission within a section of the drive unit connected downstream of the clutch aggregate.

Abstract: A transmission control system includes an up-shifting operation device, a clutch actuator, a shift actuator and a CPU. The CPU controls the clutch actuator to start a disconnection operation of a clutch at a time point when movement of an operation lever of the up-shifting operation device is started. Moreover, the CPU controls the clutch actuator to complete the disconnection operation of the clutch at a time point when the movement of the operation lever is finished. Then, the CPU shifts a gear position of a transmission by controlling the shift actuator.

Abstract: A method for operation of a drive train having a drive machine and an automatic, unsynchronized gearwheel variable-speed transmission, which can be connected to the drive machine by using an automatic clutch is described. A control device carries out a selection process as a function of vehicle parameters and/or operating variables of the motor vehicle to determine whether a gear change of the unsynchronized gearwheel variable-speed transmission will be carried out with the clutch engaged or disengaged. To ensure reliable operation of the motor vehicle, a gear change is carried out with the clutch disengaged in a time interval after initial starting up of the drive train and/or after starting of the drive machine and/or when a malfunction is identified in a component in the drive train.

Abstract: A drive control system for an automotive vehicle includes an engine, an automatic transmission, a torque converter, a start clutch, an oil pump, a hydraulic pressure control unit, an engine control unit, an automatic engine stop/restart control unit and a torque transmission control unit configured to calculate target start clutch engagement time and torque based on an accelerator opening of the vehicle, calculate a target engine torque based on the target clutch engagement torque and cause the hydraulic control unit and the engine control unit to control the engagement state of the start clutch and the output torque of the engine according to the target clutch engagement time and torque and the target engine torque at a restart of the engine.

Abstract: A vehicle control system is comprised of a controller which is arranged to select an optimal mode adapted to a driving point of a vehicle from an optimal mode map of defining a plurality of running modes of the vehicle, to detect a generation of a mode transition in the optimal mode map, and to hold a current running mode selected before the transition for a holding time period when the generation of the mode transition is detected.

Abstract: A transmission system in a vehicle using a motor to transmit power assists acceleration by generating auxiliary engine power during acceleration in addition to gear changing by the motor. Where acceleration assistance is added, torque transition is conducted along a torque transmission route of dog clutch, second intermediate shaft, motor, first intermediate shaft, and gear position of first intermediate shaft before shifting so as to avoid the torque reduction in uncomfortable shocks and feelings to the driver due to torque reduction when shifting.

Abstract: An automatic disengaging method for a master clutch dependent power take-off (PTO) arranged in a vehicle for preventing undesired movement or actions of the implements associated with the PTO and undesired wear of a clutch collar (release bearing). The PTO is driven by an engine via a master clutch between a crankshaft of the engine and an input shaft in a gearbox. The gear box further comprises an output shaft which is powered by the input shaft, optionally via an intermediate shaft. A power take-off is connected to the input shaft or, optionally, to the intermediate shaft. The system further includes a control unit connected to the master clutch and the gear box. When the control unit registers that the master clutch is disengaged, a gear is engaged in the gearbox and certain conditions are fulfilled (e.g.

Abstract: The invention concerns a multi-group transmission of a motor vehicle with at least two transmission groups (2, 3) and a method for its operation in which means are provided for supporting the traction force during gearshift operations.

Abstract: A system for controlling a dual clutch torque converter that allows for independent control of the dual clutches includes a first valve assembly, a second valve assembly, a first solenoid, and a second solenoid. The first valve assembly is operable to control whether the dual clutches are released, trimmed, or engaged. The second valve assembly is operable to control which of the dual clutches are released, trimmed, or engaged. The first solenoid is operable to control the position of the first valve assembly and the second solenoid is operable to control the position of the second valve assembly.

Abstract: The following steps are performed in the control method: determining a mode of operation from amongst a permanent mode and a transient mode, as a function of a set of variables comprising said estimated values; correcting the value of the speed of rotation of the outlet shaft in such a manner that: if the mode has been determined as being the permanent mode, then the moving average (L?) of the gear ratio (L) over a period (T) of a plurality of unit time intervals lies between a first threshold value (S1) that is negative and a second threshold value (S2) that is positive; and if the mode has been determined as being the transient mode, then said moving average (L?) of the gear ratio (L) lies outside the range of values defined by the first and second threshold value (S1, S2).

Abstract: A dual clutch transmission which has a first clutch, actuated by a first hydraulic cylinder, a second clutch, actuated by a second hydraulic cylinder, shift devices for shifting gears, which are actuated by respective hydraulically operated cylinders, a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy and a third clutch that is actuated by a third hydraulic cylinder.

Abstract: A dual clutch transmission which has a first clutch, actuated by a first hydraulic cylinder, a second clutch, actuated by a second hydraulic cylinder, shift devices for shifting gears, which are actuated by respective hydraulically operated cylinders, and a hydraulic energy source for supplying the hydraulic cylinders and the hydraulically operated cylinders with hydraulic energy. The hydraulic energy source has a first pump, a second pump and an electric drive driving the second pump.

Abstract: A transmission system having a plurality of gear ratios, a selector assembly for selectively engaging the gear ratios, and a control system arranged to measure the amount of deformation caused by torque in the transmission system in at least one static component or assembly that is deformed due to torque in the transmission system, wherein the control system is arranged to measure deformation and to adjust the torque in the transmission system according to the measured deformation and a known relationship between the gear ratios, wherein the transmission system is arranged such that selection of a new gear ratio occurs almost instantaneously without substantial power interruption.

Abstract: A vehicle including a transmission having a plurality of clutches for providing a plurality of speed ratios. A control module of the vehicle detects a possible tie-up of at least two of the clutches. Based on the detecting, the control module releases one of the possibly tied-up clutches. After the release, the control module determines whether a tie-up condition occurred. Based on the determining, the control module reapplies pressure to the released clutch. Loss of driver control of the vehicle thus can be prevented in the event of clutch tie-up.

Abstract: A control apparatus for a vehicular drive system provided with a step-variable transmission portion operable to transmit an output of an engine to a drive wheel of a vehicle and functioning as a step-variable transmission, and an input clutch operable to permit and inhibit an input of a drive force from the engine to the step-variable transmission portion, the control apparatus including an input-clutch control portion operable to reduce a torque capacity of the input clutch, during a shifting action of the step-variable transmission portion, for limiting a torque to be transmitted to the step-variable transmission portion, to a value not larger than a predetermined value.

Abstract: A method for controlling selection of an automatic transmission gear ratio with staged ratios or constant variation for a vehicle including a control for preventing/allowing extension of the gear ratio or for controlling a shortening the transmission gear ratio if, at a current engine speed, the power is insufficient for maintaining the vehicle speed. The method prevents extension of the transmission gear ratio if the power available after the extension is insufficient for maintaining the vehicle speed; otherwise allowing extension of the transmission gear ratio.

Abstract: An automatic transmission includes a planetary gear arrangement, and a plurality of engaging elements each arranged to vary an engagement state among the rotating elements of the planetary gear arrangement in such a manner to establish a normal gear ratio set and an emergency gear ratio set excluded from the normal gear ratio set. A control section of the automatic transmission performs the following: selecting a gear from the normal gear ratio set in accordance with a running state of a vehicle under normal operating conditions; controlling the engagement state of each of the engaging elements in such a manner to shift into the selected gear; detecting a failure in the engaging elements; selecting an escape gear ratio set from the normal gear ratio set and the emergency gear ratio set; and driving the vehicle with the escape gear ratio set when a failure is detected in the engaging elements.

Abstract: A vehicle include a first disconnect disposed between a prime mover of the vehicle and a certain one of the vehicle drive wheels. The first disconnect is operable to connect and disconnect the prime mover to and from the certain one of the drive wheels. A second disconnect is disposed between the powertrain and the certain one of the drive wheels, and is operable to connect and disconnect the certain one of the drive wheels to and from the powertrain when the first disconnect is engaged. A control system and method are configured to control operation of at least the first and second disconnects. Through selective control of the disconnects, the system can be automatically placed in a four-wheel-drive mode based on predetermined criteria, or the desirability of the four-wheel-drive mode can be indicated to the vehicle operator in a passive version of the control system and method.

Abstract: A pressure control system of an automatic transmission includes a control-pressure regulating valve, a path switching valve, and a coupling-pressure regulating valve. The path switching valve selectively outputs a control pressure or a line pressure, so that the coupling-pressure regulating valve regulates a coupling pressure based on the control pressure during gear shifting, and regulates the coupling pressure based on the line pressure after completion of the gear shifting.

Abstract: The invention involves a control valve arrangement to activate at least one start-up clutch of a motor vehicle automatic transmission with at least one clutch control valve (3, 3?, 3?) across which a supply pressure (P_V1) can be led into a pressure chamber of an associated clutch activation device (4, 4?), with a pressure regulating valve (166), which is controlled by an electronic control device, and at least one control valve of the control valve arrangement is supplied with a pilot pressure (P_VST3), and with a self-maintaining hydraulic unit with whose help a hydraulic emergency operation can be maintained with a closed start-up clutch upon the failure of an electronic control device and thus the absence of a pilot pressure (P_VST3) in at least many operational situations.

Abstract: A control valve arrangement having a clutch regulation valve (3), which pressurizes a device to actuate the clutch, and a valve that produces a controlled pilot pressure (P_VST3). An electronic control unit (ECU) controls a valve to supply a control valve with the pressure (P_VST3). The arrangement further having a hydraulic system which, if the ECU fails and the pressure (P_VST3) ceases, the last shift condition of the clutch actuation device, prior to the ECU failure, can be maintained in an emergency. The arrangement includes a valve, which delivers an activation pressure (P_A), depending on an engine-speed-dependent control pressure (P_D), to an actuation valve (2), which then delivers the pressure (P_A) to the valve (3) to prevent the emergency function initiation despite a lack of pressure (P_VST3) and existance of the pressure (P_D) sufficiently high to initiate the emergency function.

Abstract: In a hybrid-drive electric vehicle, upon request of gear shifting of a transmission (2), a clutch (3) is first disconnected and the transmission (2) is set to a neutral position. The rotating electric generator 4 is then operated in a motor mode or a power generating mode so that a rotational speed of an input shaft of the transmission (2) reaches a region of a synchronizing rotational speed in accordance with a requested gear position. When the rotational speed of the input shaft of the transmission (2) reaches the region of the synchronizing rotational speed, the gear position of the transmission (2) is changed over from the neutral position to the requested gear position. Thus the rotation synchronizing time for the gear shifting in the transmission (2) is reduced, making it possible to perform the gear shifting for a short period of time.

Abstract: The invention concerns a method of controlling a twin-clutch transmission (10). When the torque transmitted in a first transmission path (C1, E2, Z8, Z9, S2, Z3, Z4) reaches an upper limit given by the torque transmission capacity of that path further additional torque produced by an engine at the drive shaft (I) is transmitted by closure of the second clutch (C2) to the output shaft (O) in parallel relationship by way of a second transmission path (C2, E1, Z1, Z2, S1, Z3, Z4). That permits the output of the engine to be better utilised and makes it possible to achieve better travel characteristics.

Abstract: In an automatic transmission control system and method, an electronic control unit is programmed to output a command to establish another gear stage different from the gear stage at the time of occurrence of fault-induced disengagement by combination of engagements of the friction elements other than the friction elements to be engaged at the time of occurrence of fault-induced disengagement, and simultaneously output a plurality of commands to establish a plurality of gear stages corresponding to combination of engagements of the friction elements to be engaged and disengaged, respectively, at the gear stage at the time of occurrence of fault-induced disengagement, when the gear stage at the time of occurrence of the fault-induced disengagement is a predetermined gear stage and the friction element undergoing the fault-induced disengagement is not determined.