Jatco Corporation

Nissan Motor Company Limited

Yuuji Nagase

Hideaki Suzuki

Fumito Shinohara

Yoshio Yasui

Hiroyasu Tanaka

Hideshi Wakayama

Takuichiro Inoue

Toshiaki Noda

Takashi Koguchi

Makoto Komatsu

Sho Okutani

An automatic transmission control device implements a downshift by disengagement of a clutch that is engaged in a gear position before the downshift. It is determined whether an engine state is in a predetermined region in which a change of an engine torque per a change of an accelerator pedal opening is smaller than that in another region, and the engine torque is within a predetermined range, and an engine rotational speed is within a predetermined range. It is determined whether an operating state is in a predetermined state of accelerator operation in which the accelerator pedal opening is larger than a predetermined value, and an accelerator pedal opening change rate has an absolute value smaller than a predetermined value. The downshift is inhibited in response to determination that the engine state is in the predetermined region and the operating state is in the predetermined state of accelerator operation.

Automatic transmission control device

A first determining unit configured to determine whether the indicated pressure of a primary pulley pressure has become a line pressure during an up shift, an indicated pressure control unit configured to make the indicated pressure of the primary pulley pressure alone higher than the line pressure when the target shift rate is determined to be equal to or lower than a predetermined shift rate and the speed ratio is determined not to have become the target speed ratio, and an estimated time detecting unit configured to detect a predetermined time it takes until the primary pulley pressure can be regarded as being equal to the line pressure after the target shift rate is determined to be equal to or lower than the predetermined shift rate, and the indicated pressure of the primary pulley pressure is made higher than the line pressure, are provided, and the indicated pressure control unit is configured to calculate the deviation between the indicated pressure of the primary pulley pressure and indicated pressure of the line pressure after the estimated predetermined time is over, and control transmission of a continuously-variable transmission while maintaining the deviation after the predetermined time is over.

Continuously-variable transmission and continuously-variable transmission control method

A continuously-variable transmission, which has a first pulley, which has a first fixed pulley and a first mobile pulley, a second pulley, which has a second fixed pulley and a second mobile pulley, and a drive force transmitting member, which is stretched between the first pulley and the second pulley, is provided, and this continuously-variable transmission has an indicated pressure calculation section, which calculates the indicated pressure of the first pulley, a stroke speed calculation section, which calculates the stroke speed of the first mobile pulley, and an oil pressure calculation section, which, when oil is discharged from an oil chamber, calculates the amount of increase of oil pressure in a first pulley oil chamber that increases compared to the indicated pressure due to the channel resistance of the discharge path, based on the channel resistance and the stroke speed, and a correction section, which, when oil is discharged from the first pulley oil chamber, subtracts the amount of increase of oil pressure from the first pulley pressure based on a target speed ratio and input torque, and corrects the indicated pressure of the first pulley.

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Yokohama, Japan

Yuuji Nagase