Aisin Seiki Kabushiki Kaisha

Atuo Okumura

Masato Shimei

Takahiro Sakai

Yoshiyuki Onimaru

Yasuo Shirai

Takanao Suzuki

A shift control unit which improves the shift feeling of an automatic transmission includes an operation control device for placing a frictional engaging element in a slow drain state during a timing time decided by a timing time deciding device and in a quick drain state when the timing time has elapsed. The shift control unit is provided further with a computing device for computing the power-off engine speed necessary for outputting a small range upper limit value of a turbine torque from a number of revolutions of the turbine of the torque converter and from the performance characteristic of the torque converter, and an auxiliary operation control device for comparing the power-off engine speed and actual engine speed and for running the operation control device when the actual engine speed is equal to or greater than the power-off engine speed to place the frictional engaging element into the quick drain state immediately without running the operation control device when the actual engine speed is below the power-off engine speed.

Growing community of inventors

Toyota, Japan

Atuo Okumura