LOCK-UP CLUTCH CONTROLLER OF AUTOMATIC TRANSMISSION

PROBLEM TO BE SOLVED: To properly control the slipping amount of a lock-up clutch in lock-up clutch control performed when a vehicle in a deceleration state is re-accelerated.SOLUTION: When lock-up clutch command oil pressure which is instruced in accordance with transition from deceleration to acceleration is learned, a reaching time from a chip-in control completion point of time until a real slip rate reaches a prescribed target value or a prescribed value close thereto is measured and the learned value of the command oil pressure is updated on the basis of the length of the reaching time. Original chip-in control initial command pressure is corrected on the basis of the learned value and the clutch control of the lock-up clutch under deceleration feedback control is started according to corrected chip-in control initial command pressure. Thereby, the slipping amount of the lock-up clutch in transition from deceleration to acceleration can be properly controlled, and heat generation, the lowering of fuel efficiency, the generation of an engagement shock or the like accompanied by the excessive generation of clutch slippage can be prevented.