Jatco Corporation

Nissan Motor Company Limited

Masayuki Mannen

Hiroki Iwasa

Seiichiro Takahashi

Tatsuya Hayashi

Tomoaki Honma

Hironori Miyaishi

Yukiyoshi Inuta

Yasuhiro Endo

Morimasa Yamawaki

Yuta Suzuki

Kazuo Tomioka

Hideki Oshita

Takahiro Yamada

Yoshio Yasui

Akihiro Tanabe

Shohei Imaji

Takaaki Matsui

Sunghoon Woo

Susumu Saitou

A continuously variable transmission () has a torque convertor () having a lock-up clutch () and a continuously variable transmission mechanism (). A control unit () has a shift control unit (C) configured to be able to perform a pseudo stepwise up-shift control that varies a transmission ratio of the continuously variable transmission mechanism () stepwise, a lock-up control unit (A) configured to control an engagement state of the lock-up clutch (), and a torque control command unit (D) configured to perform a torque-down control of a driving source (). When the engagement control of the lock-up clutch () and the pseudo stepwise up-shift control are performed at the same time, the torque control command unit (D) configured to perform the torque-down control with a greater torque reduction amount.

Device and method for controlling continuously variable transmission

Control device for continuously variable transmission has continuously variable transmission mechanism (CVT) transmitting power with belt () wound around primary and secondary pulley (); torque convertor () having pump impeller (), turbine runner () and lock-up clutch (); and control unit () controlling lock-up clutch () to predetermined engagement state and controlling the CVT to predetermined transmission ratio, according to travelling condition. Control unit () is configured to, when shifting lock-up clutch () from disengagement to engagement state, control transmission ratio of CVT so that when rotation speed difference (&#x394;N) between engine speed (Ne) and turbine speed (Nt) that is rotation speed of turbine runner is predetermined rotation speed difference (&#x394;N) or less, turbine speed (Nt) approaches engine speed (Ne) more than turbine speed (Nt) of case where control of transmission ratio of CVT, which is set according to travelling condition during shift of lock-up clutch (), is continued.

Control device for continuously variable transmission

When an inertia phase of an upshift of the transmission is started during a lockup clutch engagement operation, a following command oil pressure to be used during a following lockup clutch engagement operation is learned on the basis of a slip rotation speed, which is a rotation speed difference between an input side rotation speed of the torque converter and an output side rotation speed of the torque converter, at or after a start point of the inertia phase.

Automatic transmission and learning method thereof

Growing community of inventors

Fuji, Japan

Masayuki Mannen