Patent ID: 8465395

Claim:
A control apparatus for an automatic transmission, the control apparatus comprising: a stepwise variable transmission mechanism including a plurality of engagement portions having a first engagement portion and a second engagement portion, the stepwise variable transmission mechanism being arranged to attain a target shift stage by combining a disengagement or an engagement of each of the engagement portions; a power ON/OFF state judging section configured to judge a power ON/OFF state; and a shift control section configured to control the stepwise variable transmission mechanism to a target rotational speed by disengaging the first engagement portion and engaging the second engagement portion in accordance with a torque inputted to the stepwise variable transmission mechanism, the shift control section being configured to engage one of the first engagement portion and the second engagement portion which has a function to suppress a variation of an input rotational speed of the stepwise variable transmission mechanism which is generated by a switching of the power ON/OFF state when the power ON/OFF state is switched at a shift control of the stepwise variable transmission mechanism, and to disengage the other of the first engagement portion and the second engagement portion, wherein the shift control section is configured to immediately disengage the second engagement portion on an engagement side which was formerly to be engaged during shifting when the power ON/OFF state is switched during an inertia phase at the shift control of the stepwise variable transmission mechanism, and to immediately engage the first engagement portion on a disengagement side which was formerly to be disengaged during shifting to suppress, by the first engagement portion on the disengagement side, the variation of the input rotational speed of the stepwise variable transmission mechanism which is caused by switching of the power ON/OFF state.