Nissan Motor Company Limited

Jatco Corporation

Norihira Amano

Masahiro Hamano

Youji Itou

Hajime Tasaka

Naonori Iizuka

Kosuke Abe

Yutaka Tohyama

Junki Matsui

Heo Chang Moo

Haruka Kondo

The transmission controller is configured to, when the received range position signal indicates that the range position is switched from a travelling range to a neutral range during travelling, output an instruction to disengage all of friction elements that are in an engaged state in the travelling range, output an instruction to at least one friction element before the instruction to disengage all of the friction elements that are in the engaged state in the travelling range is output, confirm a change in a rotation speed of a transmission input shaft after the instruction to disengage is output to the at least one friction element, and when there is no change in the rotation speed, diagnose that the friction element instructed to be disengaged is in an erroneously engaged state in which the friction element is not able to be disengaged.

Diagnostic device and control device for automatic transmission

The transmission control unit includes a gear ratio abnormality determination unit and a limp home control unit. The gear ratio abnormality determination unit is configured to determine that a gear ratio is abnormal when, during travelling at a predetermined gear position, a difference between an actual gear ratio, which is calculated based on a transmission input shaft rotation speed and a transmission output shaft rotation speed, and a set gear ratio at the predetermined gear position is equal to or greater than a set value. The limp home control unit is configured to, when the gear ratio abnormality determination unit determines that the gear ratio is abnormal, output a disengagement instruction for disengaging all of the plurality of friction elements, when it is confirmed that a neutral state is shifted to according to the output of the disengagement instruction, determine engagement/disengagement of a specific friction element among the plurality of friction elements based on rotation/stop information of a rotation member of the stepped transmission mechanism, and determine an evacuation gear position based on determination information on the engagement/disengagement of the specific friction element, and shift the gear position to the determined evacuation gear position.

Control device and control method for automatic transmission

An automatic transmission is arranged in a hybrid driveline employing an EV mode and an HEV mode, and establishes transmission ratio positions by engaging or disengaging frictional elements. A system or method includes: determining, based on a vehicle deceleration and a relationship between a requested transmission ratio position and an actual transmission ratio, whether or not interlocking is occurring, when the automatic transmission is in a state out of transmission shifting, wherein the interlocking is due to erroneous engagement of one of the frictional elements; and inhibiting the determination about interlocking, during a period from start of slip of a first frictional element of the automatic transmission to confirmation of convergence of slip of the first frictional element, in a situation that the first frictional element is slip-engaged for starting the engine in response to a request for mode transition from the EV mode to the HEV mode.

Interlock determination device and determination method for automatic transmission

Abnormality detection device for automatic transmission of invention has automatic transmissionA connected to vehicle driving sourcethrough clutch; range detector detecting selection range of selector leverand outputting detection signal; manual valveconfigured to, when selector lever is positioned at drive range position, engage clutch and bring automatic transmission into power transmission state, and when selector lever is positioned at range position except drive range position, disengage clutch and bring automatic transmission into power non-transmission state. Device further has engagement control unitB controlling clutch from disengagement state toward engagement direction when no-signal state in which signal is not outputted from range detector continues for first predetermined time or more; engagement judgment unitC judging engagement of clutch during engagement control; and abnormality determination unitD determining, when engagement is judged, that range detector is in no-signal abnormality indicating that no signal is outputted.

Abnormality detection device for automatic transmission

In a vehicle in which a continuously variable transmission, which is connected to an electric motor via a clutch, is operated using oil pressure of an oil pump driven by the motor, erroneous engagement of the clutch is quickly determined. The vehicle has the motor serving as a vehicle driving source, the oil pump connected to the motor, the continuously variable transmission, the clutch interposed between the motor and the continuously variable transmission, a clutch control means for controlling the clutch such that the clutch enters into a completely-engaged, slip-engaged, or release state, and a vehicle control means for controlling the motor such that the motor rotates at a target rotation speed. Also provided is an erroneous engagement handling control means that executes torque adjustment control to decrease an output torque of the vehicle driving source when the clutch is determined to be in an erroneously completely engaged state.

Control device that handles erroneous clutch engagement

A failure judgment device of an automatic transmission includes: a first abnormality judging section configured to judge a power supply fault abnormality or a breaking abnormality of the solenoid, from a selected shift stage and a state of the transmission mechanism, after the detection of the electric abnormality; and a second abnormality judging section configured to judge the power supply abnormality or the breaking abnormality of the solenoid, from the monitor current value when the solenoid valve is switched to an OFF state, after the detection of the electric abnormality, when one of the first abnormality judging section and the second abnormality judging section judges the power supply fault abnormality or the breaking abnormality, the judgement result being outputted.

Fail determination device for vehicle automatic transmissions and control device for vehicle automatic transmissions

An automatic transmission includes an oil temperature detecting unit configured to detect an oil temperature of the hydraulic oil, and a controller configured to perform the control of the speed ratio on a basis of the oil temperature obtained from the oil temperature detecting unit. The controller is configured such that if the controller has failed to obtain the oil temperature from the oil temperature detecting unit, the controller outputs a command to restrict an output from the driving force source, and such that if the controller has obtained the oil temperature from the oil temperature detecting unit again, the controller gradually cancels the command to restrict the output from the driving force source.

Automatic transmission and control method of the same

The present invention is a control device for an automatic transmission, the control device being adapted to control the automatic transmission including a torque converter and a stepped transmission mechanism provided on a power transmission route from the torque converter to drive wheels, wherein while a non-driving range of the automatic transmission is selected, determination on interlock in the stepped transmission mechanism is executed on the basis of deceleration of an output shaft of the stepped transmission mechanism and a change in the torque converter.

Control device for automatic transmission and control method for automatic transmission

The integrated controller determines whether or not, regardless of execution of the WSC control, a rotation speed of the motor generator falls to less than an idle rotation speed and also whether or not differential rotation of the second clutch becomes less than a predetermined value, and determines that, if the determination is positive, a continuous MAX pressure failure has occurred in the second clutch.

Failure determining device of hybrid vehicle and failure determining method therefor

A failure determination device of a hybrid vehicle, includes an engine, a motor arranged in series with the engine, a clutch arranged between the motor and a driving wheel, a pressure adjusting mechanism that adjusts hydraulic pressure supplied to the clutch, and that performs wet start clutch control for adjusting the hydraulic pressure, supplied to the clutch at least upon starting, to the hydraulic pressure causing the clutch to slip, and a controller configured to calculate required driving force on the basis of accelerator opening, and calculate torque capacity of the clutch, required for transmitting the required driving force by the clutch, as target torque capacity, calculate actual torque of the engine and actual torque of the motor, and calculate a torque deviation as a deviation between the target torque capacity and a sum of the actual torque of the engine and the actual torque of the motor.

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Fuji, Japan

Norihira Amano