Abstract: A shift control method for a vehicle with a Dual Clutch Transmission (DCT) includes comparing, by a controller, a current clutch temperature with a first predetermined reference value and a second predetermined reference value, the second predetermined reference value being greater than the first reference value, preventing, by the controller, coaxial power-on downshifting when the clutch temperature is greater than the first reference value, and reducing, by the controller, a shift time by preventing coaxial power-on downshifting when the clutch temperature is greater than the second reference value and then increasing a shift speed when biaxial full skip shifting is required.

Abstract: A torque converter (1) connecting an engine (14) and a transmission (15) of a vehicle is provided with a lockup clutch (2), and a controller (5) is programmed to increase an engagement force of a lockup clutch (2) under open loop control before shifting to feedback control of the engaging force using a target slip rotation speed. When an engine output torque rapidly decreases during open loop control (S59, S60), the controller (5) decreases the engaging force according to a variation amount of the engine output torque (S61, S65), thereby preventing an unintentional sudden engagement of the lockup clutch (2) due to decrease in the engine output torque.

Abstract: A method of controlling shifts in a vehicle transmission, for example a utility vehicle, having a transmission or partial transmission designed as a dual-clutch transmission that shifts as a without traction force interruption. The transmission comprises a dual clutch having a first clutch and a second clutch that are functionally connected to a drive engine, and a transmission or partial transmission comprises a main transmission that shifts with traction force interruption and is connected to a drive-train downstream from the dual-clutch transmission. During shifts in the main transmission that is connected downstream from the dual-clutch transmission, the dual clutch is operated, by pre-loading the two clutches, as a transmission brake and/or an engine brake for adapting the speed of components to be shifted so as to enable short shifting times and ensure comfortable and reliable driving operation.

Abstract: The invention relates to a process for detecting tuning measures through which the actual output power of an internal combustion engine of a motor vehicle is increased relative to design output power value, whereby, to detect the tuning measures, deviations of actual output power value from a nominal output power value are evaluated, the latter being provided by a control device. The invention is distinguished in that measures are initiated to protect a clutch device from overload as soon as torque to be transmitted by the clutch device exceeds a critical value.

Abstract: A power tool includes a housing, a motor disposed in the housing, a transmission disposed in the housing and coupled to the motor, an output end effector coupled to the transmission, a control circuit for controlling power delivery from a power source to the motor, and a force sensing electronic clutch including a force sensor coupled to a substantially stationary element of the transmission. The force sensor senses a reaction torque transmitted from the end effector to at least a portion of the transmission. The sensor is configured to generate a first electronic signal corresponding to an amount of the reaction torque. The control circuit compares the first electronic signal with a second electronic signal corresponding to a desired threshold torque value, and initiates a protective operation when a value of the first electronic signal indicates that the reaction torque has exceeded the desired threshold torque value.

Abstract: The invention relates to a process for controlling a twin clutch transmission with two partial drive trains with respectively a friction clutch interposed between an internal combustion engine and the partial drive train. If the transmission capacity of a friction clutch falls below the engine torque, engine intervention takes place. If the clutch temperature rises further above a default value, an emergency operation is initiated, in which the affected partial drive train is deactivated by opening the affected friction clutch, a preselection strategy used in the other partial drive train is changed and the other partial drive train is activated.

Abstract: A method of using a torque converter bypass clutch to launch a vehicle, mitigate transient vibration, and mitigate vehicle natural frequency harshness. The method uses the torque converter when the bypass clutch power capacity is approaching its limit, when the vehicle load is high, or the vehicle is on a grade, where normally the bypass clutch would launch the vehicle.

Abstract: A method for the advance determination of an overload of an automatically actuated clutch of a vehicle during a slippage phase and to prevent the overload. The method determines the energy introduced into the clutch during a predetermined first time span of the slippage phase and/or acquires the current temperature of the clutch and, on the basis of the anticipated second time span of the slippage phase, determines the anticipated energy introduction into the clutch and/or the anticipated clutch temperature and, as a function of the anticipated energy introduction and/or the anticipated clutch temperature, takes measures to prevent the overload.

Abstract: During a period in which a clutch is in a partially engaged state at the time of start of a vehicle, a transmission ECU calculates load acting on the clutch (clutch-absorbed energy). When this load is large, generation of a shift signal based on a gear shift map is prohibited, and the initial gear position is held. The clutch-absorbed energy is obtained through integration of the product of clutch transmission torque and the difference between rotational speed of an engine and rotational speed of the clutch. The clutch transmission torque is determined with reference to a clutch transmission torque map provided in the transmission ECU.

Abstract: A duty jumping amount at an actual shift-begin point (SB point) during static shifting is calculated dependent on an automatic transmission fluid temperature and a turbine torque. Therefore, an adjustment of hydraulic pressure supplied to an on-coming clutch at the SB point is optimized, and thereby a shift feel of an automatic transmission may be improved.

Abstract: If a user presses a clutch pedal to perform gear-shifting operation while a vehicle is traveling, a clutch disc, which has been engaged with a flywheel rotating with an engine, is brought to partial clutch engagement and slides on an end surface of the flywheel to generate friction. Thus, a first phenomenon in which a decreasing rate of the engine rotation speed rapidly increases occurs. Then, a second phenomenon in which the clutch disc is completely disengaged from the flywheel to eliminate the friction and the decreasing rate of the engine rotation speed returns to an original state occurs. If the first and second phenomena are detected successively when neither an engine side nor a power transmission system side transmits power for varying an engine rotation speed, it is determined that the clutch disc is disengaged.

Abstract: A method for altering the coupling torque of a coupling in the drive train of a vehicle with an automatic gearbox and/or automatic coupling in a creep drive mode of a vehicle. According to the invention, the coupling torque is altered according to at least one variable, the parameter of the vehicle describing the creep drive mode thereof.

Abstract: A hydraulic control apparatus for an automatic transmission having a plurality of transmission gear trains. The hydraulic control apparatus performs a gear shift operation by a select actuator and a shift actuator. When the shift actuator is actuated to a neutral position, an oil pressure is supplied from a shift position detection valve toward the select actuator which selects a gear shift stage switching mechanism. When the oil pressure is supplied by a normally open solenoid valve, and also a reverse gear stage switching mechanism is selected, a pilot pressure is supplied from a select position detection valve to a forcible reverse shift valve. Thus, one oil pressure supplied to the shift actuator is shut off. When the shift actuator actuates the reverse gear stage switching mechanism, the shift position detection valve is actuated so that the oil pressure from the select position detection valve is supplied to an input clutch.

Abstract: A system and method of controlling an automatic clutch to prevent a motor vehicle engine from stalling is disclosed. The method includes the steps of determining an engine stall threshold, detecting accelerator pedal actuation, detecting current engine speed, and comparing current engine speed to the engine stall threshold. If the engine speed is below the engine stall threshold, a controller detects and compares vehicle acceleration to predetermined threshold acceleration such that the automatic clutch is actuated only when the vehicle acceleration is below the threshold acceleration. The system includes the step of detecting foot brake position such that the automatic clutch is only actuated if the foot brake is properly actuated. The controller will then actuate the automatic clutch to proportionally decouple the engine from the transmission to prevent engine stall. The automatic clutch will remain open until detecting a predetermined clearing condition.

Abstract: A system for protecting one or more drive line components from excessive inertial torque includes a torque converter disposed between an internal combustion engine and a transmission coupled thereto, wherein the torque converter is responsive to computer control to operate in a lockup mode to directly couple the engine output shaft to the transmission input shaft and otherwise in a torque converter mode. Under conditions wherein drive line acceleration exceeds an acceleration threshold, wherein the acceleration threshold preferably corresponds to the weakest of the drive line components, a control computer is operable to force the torque converter to operate in a torque converter mode of operation to thereby electronically disengage direct connection between the engine and the transmission and then to modify fueling to thereby protect the various drive line components from damage due to excessive engine inertial torque.

Abstract: An apparatus for protecting an automatic clutch from overheating, capable of holding down the generation of heat in the clutch even when the condition in which a traveling load at a vehicle starting time exceeds a predetermined level continues for a predetermined period of time. The automatic clutch is provided in a transmission path extending between an internal combustion engine and a transmission adapted to change a speed represented by an output from the internal combustion engine.

Abstract: A method for altering the coupling torque of a coupling in the drive train of a vehicle with an automatic gearbox and/or automatic coupling in a creep drive mode of a vehicle. According to the invention, the coupling torque is altered according to at least one variable, the parameter of the vehicle describing the creep drive mode thereof.