Aisin Aw Co., Ltd.

Yoshihiro Maeda

Kenichi Tsuchida

Yoshimitsu Hyodo

Masamichi Yamaguchi

Nobuyuki Hirai

Hiroyuki Kutsubo

A hydraulic control device that includes a solenoid valve capable of supplying a first engagement pressure to the first engagement element; and a first cut valve that is interposed in an oil passage from the solenoid valve to the first engagement element and is capable of cutting off supply of a hydraulic pressure to the first engagement element, wherein only the first engagement pressure and a second engagement pressure serve as hydraulic pressures that act such that the first cut valve cuts off the supply of the hydraulic pressure to the first engagement element, and the first cut valve is switched so as to cut off the supply of the hydraulic pressure to the first engagement element when the first engagement pressure and the second engagement pressure are simultaneously supplied to the first engagement element and the second engagement element, respectively.

Hydraulic control device of automatic transmission

The present invention provides a control unit. When the control unit performs shifting from a state in which a first shift speed is established by supplying engagement pressures to both hydraulic oil chambers and engaging a predetermined engagement element to a second shift speed by switching engagement and disengagement states of engagement elements other than the predetermined engagement element (Step S), the control unit reduces the supply of the engagement pressure to one of the two hydraulic oil chambers to a level lower than that in the state in which the first shift speed is established (Step S).

Growing community of inventors

Nagoya, Japan

Yoshihiro Maeda