A method for operating a vehicle having a vehicle drive train (1) and a vehicle brake (7) downshifting an automatic transmission (3) in a coasting condition, during which at least one friction-locking shift element is to be disengaged and one form-fit shift element is to be engaged. An output torque present at a driven end (4) is at least partially supported at a drive motor (2) at the point in time of a demand for the coasting downshift. The drive motor (2) is actuated before the implementation of the coasting downshift in order to reduce the portion of the output torque which is supportable at the drive motor (2), and a portion of the output torque is supported in the area of the vehicle brake (7) by an appropriate actuation of the vehicle brake (7).

A vehicle control apparatus includes an engine, a refrigerant compressor, a lock up clutch, a throttle valve, and first, second, and third deceleration controllers. The second deceleration controller controls the lock up clutch to a slip state and controls the throttle valve openwise on the condition that the refrigerant compressor is in the stopped state on decelerated travel of a vehicle in a second speed region in which a vehicle speed is lower than a first vehicle speed and higher than a second vehicle speed lower than the first vehicle speed. The second deceleration controller controls the lock up clutch to a disengaged state and controls the throttle valve closewise on the condition that the refrigerant compressor is in the operative state on the decelerated travel of the vehicle in the second speed region.

An object of the present invention is to reduce discomfort of a driver, by appropriately controlling a vehicle, when driving a vehicle capable of changing a plurality of different traveling states of a power transmission state and a traveling state of an engine during traveling. The present invention is a vehicle control device for controlling a vehicle having a power transmission mechanism which controls a power transmission state between an engine and an axle, and braking means. The vehicle control device includes, as vehicle traveling states, a power transmission engine stop traveling state in which power is transmitted by the power transmission mechanism and fuel supply to the engine is stopped to cause the vehicle to travel, and a power shutoff brake traveling state in which power from the power transmission mechanism is shut off, the fuel supply to the engine is stopped, the braking means is controlled so that the braking force is smaller than the power transmission engine stop traveling state, and the vehicle is caused to travel.

An engine is driven at an operating point with high engine efficiency to improve fuel economy. A vehicle control device according to the present invention controls a transmission ratio before increasing the engine rotation speed, and thereafter, engages the clutch.

An internal combustion engine control device is provided. The internal combustion engine control device is provided with a generator that is driven by exhaust gas of the internal combustion engine. The internal combustion engine control device is capable of increasing the power generation of the generator. The internal combustion engine control device includes an exhaust amount control unit. The exhaust amount control unit increases the amount of the exhaust gas supplied to the generator in a coasting state.

A power-train controlling apparatus controls a power train of an engine electric hybrid vehicle. The power train is provided with an engine, a catalytic converter, an oxygen-level sensor, an engaging element, and an electric rotating machine. The power-train controlling apparatus includes a fuel injection controller, a catalyst diagnosing unit, and an engaging-element controller. The fuel injection controller stops fuel injection to the engine during coasting of the vehicle while the engaging element is engaged, introduces oxygen to the catalytic converter, and resumes the fuel injection in a fuel-rich state while the vehicle is running. The catalyst diagnosing unit diagnoses the catalytic converter after the resuming of the fuel injection. The engaging-element controller prohibits transition of the engaging element to a released state during a period between the stopping of the fuel injection and completion of the diagnosing of the catalytic converter.

A vehicle control device has an engine, automatic transmission, and torque converter disposed between the engine and the automatic transmission. The torque converter includes a lockup clutch coupling an input member to an output member of the torque converter. The control device has: a slip control portion controlling lockup clutch slip when deceleration running; and a fuel cut control portion performing an engine fuel cut when deceleration running and to terminate the fuel cut when an engine rotation speed is reduced to a predetermined rotation speed or less during the fuel cut, the fuel cut control portion being permitted to perform the fuel cut, based on lockup clutch slip pressure controlled by the slip control portion has reached a slip pressure value at which the engine rotation speed does not decrease due to a shortage of torque capacity of the lockup clutch even when the fuel cut is performed.

The invention relates to a drive train for a hybrid vehicle with an internal combustion engine, with a transmission and with an electric machine, wherein the electric machine is arranged between the internal combustion engine and the transmission. The drive train can be provided in a simple, economical and/or space-saving manner in that the transmission comprises at least one overrun-enabled forward gear transmitting traction torque only and at least one overrun-free forward gear. A hybrid vehicle can be operated with a drive train of this kind easily and efficiently in that, when an overrun-enabled forward gear transmitting only traction torque is engaged and while the vehicle speed lies below a certain engagement speed for an overrun-free forward gear and at least one criterion for the presence of a driving torque is established or satisfied, the transmission is shifted into the overrun-free forward gear.

A system, method, and apparatus includes management of coasting during operation of a vehicle having an engine that is selectively engageable to a driveline, a cruise control mode of operation, and a road speed governor mode of operation. A road speed governor mode of operation of the vehicle is active in response to a road speed governor operation condition being present wherein the driveline is engaged with the engine. When a coasting management condition is present, operation of the vehicle in the road speed governor mode is disabled, the driveline is disengaged from the engine, and the vehicle is operated in a coasting mode of operation. The coasting mode of operation can be canceled when a coasting mode of operation cancellation condition is present to operate the vehicle in a road speed governor mode of operation with the driveline re-engaged with the engine.

A driver assistance system in a motor vehicle, by which system, when the cruise control is activated, a predefined target speed is maintained essentially constantly via an electronic control device and sensors connected thereto. Depending on a control error with respect to the predefined speed, a drive system and/or a brake system is actuated with the aim of compensating the control error. The electronic control device is configured such that when a coasting mode is present with the cruise control actuated the current speed is detected by way of the sensors and the coasting mode is maintained despite a target-speed-dependent maximum permissible speed having been reached.