COAST-SYNC-COAST DOWNSHIFT CONTROL METHOD FOR CLUTCH-TO-CLUTCH TRANSMISSION SHIFTING

摘要

COAST-SYNC-COAST DOWNSHIFT CONTROL METHOD FOR CLUTCH-TO-CLUTCH TRANSMISSION SHIFTING A coast-sync-coast control method for clutch-to-clutch shifting in which an engine control is employed to synchronize the engine speed with the transmission input speed at a point where the input speed would otherwise exceed the engine speed. The shift is referred to as a coast-sync-coast shift since (1) it is initiated at a coast condition where the input speed is higher than the engine speed, (2) it is completed at a synchronous condition where the speed differential across the on-coming clutch is at or near zero, and (3) a coast condition recurs immediately after the shift.