Toyota Jidosha Kabushiki Kaisha

Tomoya Iwami

Keisuke Ota

Ayumu Sagawa

When a jump downshift via an intermediate shift stage is requested and a rotation speed of an input shaft approaches a synchronous rotation speed of the intermediate shift stage, a target torque phase time when the gear shift via the intermediate shift stage is performed with input switching is set to be shorter than that when the gear shift via the intermediate shift stage is performed without using input switching and torque phase control is performed. Accordingly, it is possible to promptly perform engagement of an engagement-side frictional engagement element at the time of passing through the intermediate shift stage and to rapidly perform the gear shift after passing through the intermediate shift stage.

Controller for automatic transmission

When an input torque becomes greater by a predetermined value or more due to an operation of increasing an amount of accelerator depression amount or the like during a gear shift, a controller for an automatic transmission updates a target gear shift characteristic value to a target gear shift characteristic value which is set when the gear shift is started with the input torque based on the input torque at the updating time, and performs gear shift control from a degree of progress in gear shift at the updating time based on the updated target gear shift characteristic value. Since the target gear shift characteristic value can be changed with respect to an increase in the input torque during the gear shift by this control, it is possible to prevent a decrease in durability of frictional engagement elements.

When a power-on downshift via an intermediate shift stage accompanied by input switching control is required and a predetermined shift stage is a shift stage lower than the intermediate shift stage, an electronic control unit performs torque phase control in a torque phase control time shorter than the torque phase control time that is set when the predetermined shift stage is a shift stage higher than the intermediate shift stage. Accordingly, it is possible to complete disengagement of a disengagement-side element early and to suppress a rapid increase of an input shaft rotation speed due to a clutch torque remaining.

Growing community of inventors

Chita-gun, Japan

Tomoya Iwami