A transmission control system and method involve receiving, by a controller and from a turbine shaft speed sensor, a rotational speed of a turbine shaft of an automatic transmission, receiving, by the controller and from an output shaft speed sensor, a plurality of rotational speeds of an output shaft of the transmission, determining, by the controller, a shift time modifier based on the turbine shaft speed and a gradient of the output shaft speed, modifying, by the controller, a shift time for a pedal-off downshift of the transmission based on the shift time modifier to obtain a modified shift time, and controlling, by the controller, the pedal-off downshift of the transmission based on the modified shift time.

Disclosed are a hybrid electric vehicle which may minimize fuel efficiency loss by shift intervention, and a method of controlling shift thereof. The method of controlling shift of the hybrid electric vehicle includes predicting torque of an input terminal of a transmission at a shift time, predicting an RPM of a motor at the shift time, predicting a quantity of intervention using the predicted torque of the input terminal of the transmission and the predicted RPM of the motor, determining whether or not intervention using the motor alone at the shift time is feasible based on the predicted quantity of intervention, and executing shift corresponding to a result of the determination.

While a vehicle is coasting with an engine being automatically stopped and a power transmission path between the engine and wheels being disengaged, when a deceleration request is made and the engine is restarted with the power transmission path being engaged, a deceleration level increases relative to the deceleration level required by a driver or the vehicle, thereby lowering drivability. A vehicle control apparatus includes a deceleration level control unit that controls the deceleration level of the vehicle such that, during travelling of the vehicle continuing to travel with a power transmission mechanism between the engine and the wheels being disengaged, when the deceleration request is made and the engine is started by an engagement of the power transmission mechanism, the deceleration level becomes a target deceleration level calculated from a first target deceleration level generated after the engagement of the power transmission mechanism is complete and a second target deceleration level generated in response to the deceleration request.

When an inertia phase has started while torque phase control is being executed, the torque phase control is ended, a target torque capacity of an engaging element in inertia phase control is corrected on the basis of a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element at the time when the torque phase control has completed (or a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element, which is set at the time when the inertia phase control has started), and the inertia phase control is started.

A system and method for controlling performance of a vehicle engine by sensing and/or accessing data regarding the driving environment and adjusting at least one of an engine output torque limit and a shifting schedule for the vehicle based on the sensed data.

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 control device for a continuously variable transmission includes a wheel speed difference sensing section configured to sense a wheel speed difference between the driving wheel and the driven wheel from a detection value of the first rotation speed sensor and a detection value of the second rotation speed sensor; and a clamping force increasing section configured to increase a clamping force for sandwiching a belt of the continuously variable transmission by a pulley when the wheel speed difference becomes equal to or greater than a first predetermined value, relative to a case where the wheel speed difference is smaller than the first predetermined value.

A vehicle control apparatus includes: a transmission shifting control portion configured to implement a shifting action of a step-variable transmission, by controlling a releasing action of a releasing coupling device and an engaging action of an engaging coupling device; a torque control portion configured, during the shifting action of the step-variable transmission, to implement a feedback control to control an input torque inputted to the step-variable transmission, such that a value representing a state of a rotary motion of an input rotary member of the step-variable transmission coincides with a target value dependent on a degree of progress of the shifting action; and a backup control portion configured, when it is determined that the drive wheels are slipped, to inhibit the feedback control, and to compensate a transmitted torque to be transmitted through an initiative coupling device, such that the shifting action is facilitated by compensation of the transmitted torque.

A torque transmission device is provided that is capable of being compactified as much as possible in a direction of parallel arrangement of a pair of side gears while ensuring a differential function and a differential limiting function. The torque transmission device comprises side gears (5L, 5R) coupled to rear wheels (3L, 3R), a case (6) disposed on the outer circumferential side of the side gears (5L, 5R) and rotating around the axis of the side gears (5L, 5R), and a pinion gear (12) rotatably supported by the case (6) and engaged with the side gears (5L, 5R) in a straddling manner. Additionally, the side gears (5L, 5R) are made up of spur gears different in the number of teeth, the pinion gear (12) is a spur gear and is disposed with an axial direction thereof directed in the same direction as the axial direction of the side gears (5L, 5R), and the pinion gear (12) is associated with a motor (15).

When an inertia phase has started while torque phase control is being executed, the torque phase control is ended, a target torque capacity of an engaging element in inertia phase control is corrected on the basis of a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element at the time when the torque phase control has completed (or a difference between the target torque capacity of the engaging element at the time when the inertia phase has started and the target torque capacity of the engaging element, which is set at the time when the inertia phase control has started), and the inertia phase control is started.