AUTO TRANSMISSION CONTROL METHOD FOR INCREASING FUEL-EFFICIENCY

摘要

PURPOSE: A clutch control method of an automatic transmission for an improvement of fuel efficiency is provided to improve fuel efficiency by performing a coast drive while minimizing an engine brake. CONSTITUTION: An engine power is inputted to an input shaft(10) through a torque converter. A second clutch(C1) and a third clutch(C3) operate. The slip control of the second clutch and the third clutch is performed. An engine brake torque reduces a direct action which acts on an output shaft. A delivery of a torque which is caused by an engine brake to a final output shaft(18) of automatic transmission is minimized. [Reference numerals] (AA) Engine brake torque; (BB) Input; (CC,DD) Clutch sleep; (EE) Output; (FF) Vehicle rotation direction and gradient torque direction