Aisin Aw Co., Ltd.

Shoichiro Araki

Hiroshi Tsutsui

Nobuhiro Iwai

Haruki Sato

Takafumi Hayashi

An automatic transmission control device for improving shift feel includes a pressure regulating device that regulates a friction engagement element, and transmits power to an output shaft, which is input to an input shaft through a change of a shift speed by controlling the pressure regulating device to switch an engagement state. When changing shift speed while applying torque to the input shaft, the transmission changes the shift speed via (1) a torque phase where torque is changed according to shift speed after shifting, and (2) an inertia phase where an input shaft rotation speed is changed according to the shift speed after shifting. During a shift speed change, the regulating device executes the torque phase by engaging the engagement element at a predetermined pressure with slip and standby, and executes the inertia phase by reducing an amount according to the shift speed so a shifting condition falls within a predetermined range regardless of changed shift speed, and reduces input shaft torque by a set amount, while standing by at the predetermined engagement pressure.

Automatic transmission control device, transmission device, and power output device

A shift controller controls a downshift to a low shift speed, spaced apart from a high shift speed by two or more steps, through an intermediate shift speed, by first releasing first and second shift release elements, then engaging a first shift engagement element, and finally engaging a second shift engagement element, while controlling the torque capacity of the second shift release element by feedback control. As a result of releasing the first and second shift release elements before engaging the first shift engagement element, it is possible to rev up an input rotation at maximum performance of an engine to reduce the time for shifting. As a result of the feedback control of the torque capacity of the second shift release element after engaging the first shift engagement element, a torque fluctuation at the intermediate shift speed can be reduced to avoid occurrence of an uncomfortable shift shock.

Growing community of inventors

Anjo, Japan

Shoichiro Araki