Patent ID: 6856880

Claim:
An automatic shift transmission for a vehicle having an engine mounted on the vehicle, an input shaft in connection with the engine through a main clutch; an output shaft in connection with a drive wheel, a plurality of gear trains to transmit the driving power from said input shaft to said output shaft at different ratios, and a gear-shifting mechanism which shifts said gear trains, a controller for controlling said shift mechanism so that one of said gear trains is engaged according to a position of a shift lever, comprising: a sub-clutch that engages and disengages so that one of said gear trains, other than a first-speed gear train and a reverse gear train, is engaged or disengaged, and the controller controls so that 1) when said vehicle is parked, said reverse gear is engaged, said main clutch is engaged, and said sub-clutch is disengaged, and so that 2) when preparation for engine start-up is commenced when the vehicle is parked, then said main clutch is disengaged and said sub-clutch is engaged.