| 摘要 |
PROBLEM TO BE SOLVED: To suppress a shift shock generated at the time of shift so as to favorably execute shift action by coping with a shock during a predetermined shift period that two frictional elements are released and one frictional element is fastened. SOLUTION: In a torque demand shift, releasing action is preceded and a frictional element is slipped, thereby a turbine rotational speed is increased accompanied by the increase of an engine speed, and also a fastening side frictional element is fastened at a point of time when raised near to the previously calculated turbine rotational speed after shift, and further a releasing side frictional element is completely released, therefor a target shift stage is achieved. In this case, operating pressure to the releasing side frictional element, that is, the fastening force and the slip rate of the frictional element, are controlled, thereby the turbine rotational speed is immediately increased up to a rotational speed Ntio after shift for the purpose of improving responsiveness of shift while the increasing turbine rotational speed is feedback controlled so that a rotational speed Nt is matched to a target rotational speed Ntio (chain line) per control cycle. |
