Patent ID: 8244441

Claim:
An automatic transmission control device for controlling an automatic transmission that includes a pressure regulating device that regulates an engagement pressure of at least one friction engagement element, and is capable of transmitting power to an output shaft, which is input from a power source to an input shaft through a change of a shift speed by controlling the pressure regulating device to switch an engagement state of the friction engagement element, wherein when the shift speed is changed while torque is applied to the input shaft, the automatic transmission changes the shift speed through two phases that respectively are a torque phase in which a transmission of the torque is changed to be made in accordance with a shift speed after shifting, and an inertia phase in which a rotation speed of the input shaft is changed to a rotation speed corresponding to the shift speed after shifting, wherein when the change of the shift speed is commanded, a command is issued to a power source side and the pressure regulating device is controlled so that the torque phase is executed by engaging the friction engagement element at a predetermined engagement pressure with slip and standing by, and the inertia phase is executed by setting a target reduction amount in accordance with the shift speed commanded to be changed so as to allow a shifting condition to fall within a predetermined range regardless of the shift speed to be changed, and reducing the torque applied to the input shaft from the power source based on the set target reduction amount, while standing by at the predetermined engagement pressure, and wherein the target reduction amount is set to have a tendency in which the torque is reduced by a larger amount as a step ratio when the shift speed commanded to be changed becomes larger.