Nissan Motor Company Limited

Hiroki Shimoyama

Hiroki Matsui

Haruhisa Tsuchikawa

Munetoshi Ueno

Yutaka Takamura

Takefumi Suzuki

Hiroyuki Ashizawa

Hiroshi Arita

Hiromichi Murata

Yuya Kogure

Takamura Yutaka

Arita Hiroshi

The present invention provides a shift control method include: setting a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift; determining whether or not an accelerating intention is present when the shift is a downshift with a driving force requirement to the vehicle; when the accelerating intention is present, setting a first target input shaft rotation speed as the target input shaft rotation speed, the first target input shaft rotation speed being obtained by increasingly correcting the basic target synchronization rotation speed; and when the accelerating intention is not present, setting a second target input shaft rotation speed as the target input shaft rotation speed, the second target input shaft rotation speed being obtained by maintaining or decreasingly correcting the basic target synchronization rotation speed.

Shift control method and shift control system

The present invention provides a shift control method implemented in a vehicle equipped with an automatic transmission for controlling an input shaft rotation speed to a target input shaft rotation speed during a shift. The method includes setting of a basic target synchronization rotation speed that is a basic target value of the input shaft rotation speed during the shift, and setting of a corrected target input shaft rotation speed as the target input shaft rotation speed when the shift is a downshift without a requirement for a driving force of the vehicle, The corrected target input shaft rotation speed is obtained by decreasingly correcting the basic target synchronization rotation speed. Further, a decreasing correction amount of the basic target synchronization rotation speed is set so as to become larger as a deceleration of the vehicle becomes larger.

An object of the invention is to provide a hybrid vehicle control device capable of shortening the time from an engine start request to the engine start. The hybrid vehicle control device is provided with an integrated controller configured to execute processing for starting an engine by bringing a first clutch into engagement, while slipping a second clutch, and by increasing a torque of a motor generator, when it has been determined that an engine start request is present, and a first clutch engagement control section, which is included in the integrated controller and configured to command a start of engagement of the first clutch once the difference between the torque of the motor generator and a second clutch transmitted torque capacity command value becomes greater than or equal to a preset slip prediction determination threshold value after having been determined that the engine start request is present.

Hybrid vehicle control device

An adaptive control device is provided for a vehicle starting clutch. The adaptive control device includes a reverse brake as the starting clutch, and a clutch adaptive controller. The reverse brake is interposed between an engine and motor/generator, and the left and right rear wheels and is slip-engaged at a time of starting. The clutch adaptive controller performs clutch adaptive control, in which the reverse brake is subjected to a state in which a temperature of the reverse brake is at, or above, a second threshold for a timed period, at least one time before a vehicle begins to move.

Adaptive control device for vehicle starting clutch

A hybrid vehicle control device includes an engine start control unit which, at engine start, starts slipping a second clutch, sets a first clutch to a slip-engaged state, and sets the second clutch transmission torque capacity to less than or equal to a set torque limit value during cranking, maintains the slip state and cranks the engine, and when the engine is put in a drive state, controls the first clutch and the second clutch towards a fully engaged state. The engine start control unit is provided with a second clutch torque increase gradient control unit which, when performing cranking processing, performs first increasing processing for increasing the second clutch transmission torque capacity command value at a first increase gradient, and second increasing processing for increasing said value at a second increase gradient more gradual that the first increase gradient.

The hybrid vehicle control device includes: a transfer-torque-capacity command-value correcting section configured to execute a correcting processing such that a transfer-torque-capacity command value for a second clutch is corrected at the time of execution of a minute slip processing; an engine start control section configured to execute an engine start control such that an engine is started by slipping the second clutch and increasing drive torque of a motor/generator; a start-time slip control section configured to execute a slip-in processing such that a transfer torque capacity of the second clutch is controlled to a predetermined slip-in torque when the second clutch starts to slip by the engine start control; and a correction limiting section configured to execute a correction limiting processing such that a correction amount is limited if a torque reduction given by the slip-in processing interferes with a torque reduction given by the correcting processing.

Provided is a hybrid vehicle in which a motor/generatoris positioned between an engineand an automatic transmission, the engineand the motor/generatorare connected through a first clutchand a second clutchis provided between the motor/generatorand a drive road wheel. In an HEV mode in which the first clutchis engaged, when deceleration of a vehicle is determined to be rapid deceleration of a threshold value or greater, the first clutchis released and at the same time fuel supply to the engineis stopped through an engine controller. Even when, due to rapid decelerating, the engine speed Ne drops to an idling speed or lower due to delay in the release of the first clutch, there is no combustion or explosion and thus floor vibration does not occur.

Hybrid vehicle rapid deceleration control device

A hybrid vehicle control device basically includes an engine, a motor/generator, a first clutch, a second clutch and an engine start control section. The first clutch is disposed between the engine and the motor/generator. The second clutch is disposed between the motor/generator and a drive wheel. The engine start control section has a second clutch slip transition control section that is configured to control a transition of the second clutch to slip engagement when an engine start control is begun based on a mode transition request resulting from an accelerator depression operation, by increasing the torque transmission capacity of the second clutch according to a prescribed slope after dropping the torque transmission capacity of the second clutch to a value smaller than a target drive force.

Control device for hybrid vehicle

A control device for a hybrid vehicle has an engine, a motor configured to output a driving force of the vehicle and performing a startup of the engine, a first engagement element interposed between the engine and the motor that selectively connects and releases the engine and the motor, a second engagement element interposed between the motor and a driving wheel that selectively engages and releases the motor and the driving wheel, a driving force transmission system load detecting device that either detects or estimates a load of the driving force transmission system, and an engine/motor slip drive control unit that slip engages the first engagement element with the engine maintaining in rotating state at a predetermined rotation speed, and slip engages the second engagement element with the motor at a rotation speed lower than the predetermined rotation speed.

A gradient determination control unit releases the hold of a gradient determination result when a state where a road surface gradient detected by a gradient detection unit is smaller than a gradient release determination threshold value continues for a second predetermined time or longer if a vehicle is determined to be in a traveling state by a traveling state determination unit, and releases the hold of the gradient determination result when the road surface gradient detected by the gradient detection unit becomes smaller than the gradient release determination threshold value if the vehicle is determined to be in a stopped state by the traveling state determination unit.

Provided herein is a vehicle drive force control. When a driver requests to start the vehicle with the brake OFF and depresses the accelerator pedal, a target drive torque exceeds a gradient load. To avoid excess current being supplied to the motor, the upper limit of motor speed, which is the input speed of a second clutch, is set to a value less than a slip detectable limit value at which it becomes possible to detect slip rotation, i.e. the difference over the output side rotation speed. When the target drive torque exceeds the gradient load, the lower limit of the input speed of the second clutch (the motor speed) is set to a value equal to or greater than the slip detectable limit value so that the required driving force can be achieved by the gradient load corresponding driving force control.

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Ebina, Japan

Hiroki Shimoyama