DEVICE FOR CONTROLLING AUTOMATIC TRANSMISSION

A device for controlling an automatic transmission includes a lock-up clutch control means for executing feedback control to conform an actual slip amount of lock-up clutch (8) with a target slip amount, and a zero slip control means for bringing lock-up clutch (8) into a zero slip state immediately before slippage occurs in accordance with a zero slip request outputted during a non-gear shift. Upon transition to the zero slip state, the zero slip control means fixes the target slip amount to a slip amount threshold value and retains the fixed target slip amount for a predetermined period of time (t2-t3), and after the predetermined period of time has elapsed, gradually decreases the target slip amount from the slip amount threshold value to a zero slip amount with a predetermined gradient (¸2) with time.