Jatco Corporation

Nissan Motor Company Limited

Youji Itou

Kosuke Abe

Masahiro Hamano

Norihira Amano

Haruka Ozono

Kiyofumi Sasaki

Naonori Iizuka

Hajime Tasaka

Takamitsu Shimazu

Heo Chang Moo

Haruka Kondo

In a transmission control device for controlling a transmission, a controller determines failure of a specific section. The controller variably controls line command pressure and secondary command pressure, and in a case where the failure is determined, fixes the line command pressure to a line pressure set value and the secondary command pressure to a secondary pressure set value. In a case where the failure is determined, the controller further starts a change in the secondary command pressure after start of a change in the line command pressure, and controls the secondary command pressure in such a manner that the secondary command pressure takes a first predetermined time to have the secondary pressure set value.

Transmission control device and transmission control method

In a transmission control device for controlling a transmission, a controller determines failure of a SOL corresponding to a hydraulic secondary-pressure actuator. The controller variably controls line command pressure, and in a case where the failure is determined, fixes the line command pressure to a line pressure set value. The controller variably controls primary command pressure, and in a case where the failure is determined, continuously changes a speed ratio of a variator by variably controlling the primary command pressure. The controller variably controls secondary command pressure, and in a case where the failure is determined, fixes the secondary command pressure to a secondary pressure set value.

In a transmission control device for controlling a transmission, a controller determines failure of a SOL corresponding to a hydraulic primary-pressure actuator. The controller variably controls line command pressure, and in a case where the failure is determined, continuously changes a speed ratio of a variator by variably controlling the line command pressure. The controller variably controls primary command pressure, and in a case where the failure is determined, fixes the primary command pressure to a primary pressure set value. The controller variably controls secondary command pressure, and in a case where the failure is determined, fixes the secondary command pressure to a secondary pressure set value.

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

A hydraulic switch malfunction assessment device includes a solenoid valve disposed in a hydraulic circuit of an automatic transmission and having a characteristic such that a hydraulic pressure supplied to a frictional engagement element changes due to a change in an electric current supplied to the solenoid valve, and a hydraulic switch interposed between the solenoid valve and the frictional engagement element and configured to output an ON signal when the hydraulic pressure is higher than or equal to a threshold value and output an OFF signal when the hydraulic pressure is less than the threshold value. Also provided is a controller configured to control the supplied current to a prescribed current value or less when a predetermined running condition has been met, and then assess a malfunction of the hydraulic switch, based on a state of operation of the solenoid valve and the signal from the hydraulic switch.

Hydraulic switch malfunction assessment device

A control device for a continuously variable transmission of a vehicle includes a shift control section being configured to perform a rough road corresponding control to increase the hydraulic pressure to a value larger than the hydraulic pressure at a smooth road judgment at which the smooth road is judged, at a rough road judgment at which the rough road is judged, and when a line-pressure-up control condition is satisfied at the rough road judgment, the line pressure control section being configured to increase the line pressure to be greater than the line pressure when the line-pressure-up control condition is not satisfied.

Control device for continuously variable transmission for use in vehicles

A control device for a continuously variable transmission of a vehicle includes: a shift control section being configured to perform a rough road corresponding control to increase the hydraulic pressure supplied to the secondary pulley to a value larger than the hydraulic pressure at a smooth road judgment at which the smooth road is judged, at a rough road judgment at which the rough road is judged, and thereby to increase the clamping force of the secondary pulley with respect to the circular belt member; and a rotation speed control section being configured to control the transmission gear ratio at the rough road judgment so that a rotation speed of the primary pulley becomes equal to or greater than a lower limit rotation speed which is previously set.

Vehicle stepless transmission control device

There are provided a continuously variable transmission (CVT) in which a belt () is wound around a primary pulley () and a secondary pulley () to transmit power; a primary pulley rotational speed sensor () for detecting a rotational speed of the primary pulley (); a vehicle stopped state determination means for determining whether a vehicle is in a stopped state; a belt slippage detection means for detecting belt slippage on the basis of a signal of the primary pulley rotational speed sensor (); and a prohibition means for prohibiting detection of the belt slippage by the belt slippage detection means when a parking range or a neutral range is selected by a shift lever operation by a driver. In the vehicle stopped state during selection of the parking range or the neutral range, the rotational speed of the primary pulley () is not basically output, and the belt slippage does not occur. Thus, erroneous detection of the belt slippage can be avoided by prohibiting the detection of the belt slippage in this case.

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Sagamihara, Japan

Youji Itou