The invention relates to a method for controlling a drivetrain having an internal combustion engine controlled dependent on a load demand on a target engine torque and having a dual-clutch transmission with two sub-transmissions, each having a friction clutch positioned operatively between the internal combustion engine and a sub-transmission with a changing maximum transferable clutch torque, wherein a specified clutch torque is set along an actuation travel path by means of a clutch actuator, a clutch characteristic of the transferable clutch torque is continuously adapted over the actuation travel path, and a maximum engine torque for a sub-transmission, which is reduced in comparison to the target engine torque, is limited to the maximum clutch torque transferable by means of the friction clutch of that sub-transmission.

Systems and methods for cranking an engine of a hybrid vehicle that includes an electric machine to crank the engine and propel the vehicle are disclosed. In one example, engine cranking speed and engine cranking source are selected in response to vehicle operating conditions that may affect whether or not an electrical power source has sufficient energy to crank the engine.

A control system for a hybrid vehicle configured to avoid unintentional reduction in a driving force is provided. The control system is configured to estimate a vehicle speed after a predetermined period of time during propulsion of the vehicle under single-motor mode, and to shift the operating mode directly from the single-motor mode to an engine mode while skipping a dual-motor mode, if a current operating point of the vehicle enters into an operating region where both of the second mode and the third mode are available but the operating mode is expected to be further shifted to the engine mode.

An overheat prevention method includes an rpm comparison step of comparing an engine revolution per minute (rpm) speed with a preset rpm speed by a controller when requiring an engagement of an engine clutch, a temperature comparison step of comparing a temperature of a transmission clutch with a preset temperature by the controller when it is determined that the engine rpm speed is less than the preset rpm speed at the rpm comparison step, and a serial drive mode control step of releasing the engine clutch and engaging the transmission clutch, and controlling a hybrid starter generator (HSG) to charge a battery using engine power to provide driving power to a motor by the controller when it is determined that the temperature of the transmission clutch is higher than the preset temperature at the temperature comparison step.

Provided is a control device for a vehicle including a continuously variable transmission. The control device includes a lock-up clutch, an oil pump, an electric motor, and a device control unit. The lock-up clutch is disposed in a torque converter coupled to the engine and switchable between an engaged state and a released state. The oil pump is driven by the engine and supplies a hydraulic oil to the continuously variable transmission. The electric motor is coupled to the engine and controlled to be in a powering state in which the engine is rotationally driven. The device control unit controls the lock-up clutch to put into the released state and controls the electric motor to put into the powering state if a discharge pressure of the oil pump falls below a threshold value at the time of a vehicle deceleration in which a fuel supply to the engine is cut off.

A method for controlling a line pressure of a hybrid vehicle includes applying, by a controller, a set current corresponding to a target pressure to a first solenoid valve controlling the line pressure, driving, by the controller, a second solenoid valve to open an engine clutch after the applying step, comparing, by the controller, a difference value between a real pressure of the engine clutch sensed by a pressure sensor and the target pressure with a preset pressure after the driving step, and as a result of performing the comparing step, if the difference value is equal to or greater than the preset pressure, controlling, by the controller, an increase of a revolution per minute (RPM) speed of the electric oil pump and an increase of a pressure of the first solenoid valve to be alternately generated.

In response to a DN operation that changes a shift position SP from a D position to an N position during forward drive in an HV drive mode, then an accelerator position Acc is not less than a reference accelerator position Aref (step S130), a mechanical neutral control is performed to provide a neutral state by releasing transmission of power between an intermediate shaft 32 and a driveshaft 36 by a multi-speed transmission 60 (step S230). An engine and two motors are then controlled to be rotated at rotation speeds close to rotation speeds Nedn, Nm1dn and Nm2dn at the time of DN operation (steps S250, S270 and S280).

A method for starting a combustion engine of a hybrid motor vehicle drivetrain, in which there is a connection clutch interposed between the combustion engine and the electric motor for transmitting a torque between the combustion engine and the electric motor, and a main clutch interposed between the gearbox and the electric motor. From an initial state in which the electric motor generates a drive torque and the combustion engine is stopped, the main clutch is kept in a closed state so as to transmit the torque generated by the electric motor to the gearbox, and the connection clutch is controlled so as to transmit a drive torque between the electric motor and the combustion engine and perform a torque-limiting function between the combustion engine and the electric motor in order to limit the transmission of acyclisms between the combustion engine and the electric motor.

A hybrid-vehicle system includes an internal combustion engine configured to deliver a first rotational torque to a crankshaft. The first rotational torque is a maximum torque deliverable by the internal combustion engine. The hybrid-vehicle system also includes a transmission selectively rotatably coupled to the crankshaft, and an assembly including an electric machine rotatably coupled to the transmission and configured to deliver a second rotational torque directly to the transmission. The assembly also includes a one-way clutch configured to rotationally couple the crankshaft and the transmission. The assembly further includes a friction clutch moveable between an engaged state where the crankshaft and the transmission are rotationally coupled, and a disengaged state where the crankshaft and the transmission are rotationally decoupled. The friction clutch is further defined as a latching friction clutch.

A working vehicle includes a prime mover, a traveling device, a traveling clutch switchable between an engaged state to transmit, to the traveling device, power provided from the prime mover and a disengaged state to interrupt the power transmitting to the traveling device, an automatic switching controller to switch the traveling clutch from the disengaged state to the engaged state, and a status detector to detect at least either a status of the prime mover or a status of the traveling device. The automatic switching controller changes a switching speed of the traveling clutch switched from the disengaged state to the engaged state based on the status detected by the status detector.