Patent ID: 8255135

Claim:
A control method of shifting gear in an automatic manual transmission having a twin-clutch gearbox to pass from a current gear (A) to a successive gear (B); the automatic manual transmission comprising a twin-clutch gearbox presenting two primary shafts, at least a secondary shaft connected to driving wheels and two clutches, each of which is interposed between a drive shaft of an engine and a corresponding primary shaft, the control method comprises the steps of: establishing, before starting the gear shifting and as a function of the feelings to be given to the driver, how rapidly the reaction to the gear shifting command is to be and also how much to accentuate a “torque interruption”, i.e. an “acceleration gap”, during the gear shifting; receiving a gear shifting command at a first moment (T 0 ); closing at the first moment (T 0 ), a first clutch which is associated to the successive gear (B) and starts transmitting torque at a second moment (T 1 ) after a delay time (T R ) interval has elapsed since the beginning of the closure; opening, at a third moment (T 4 ), a second clutch associated to the current gear (A), which implies decreasing the torque transmitted by the second clutch, before the first clutch starts transmitting torque, so that the second clutch decreases the torque transmitted to the driving wheels before the first clutch starts transmitting torque to the driving wheels; completing the closure of the first clutch at a fourth moment (T 2 ); completing the opening of the second clutch at a fifth moment (T 5 ); establishing the third moment (T 4 ), in which the second clutch starts opening, depending on how rapidly the reaction to the gear shifting command is to be, so that the higher the reaction rapidity is, the closer the third moment (T 4 ), in which the second clutch starts opening, is to a first moment (T 0 ), in which the gear shifting command is received; and including establishing the fifth moment (T 5 ), in which the opening of the second clutch is completed, depending on how much to accentuate an “acceleration gap” during the gear shifting, so that the bigger the “acceleration gap” during the gear shifting is, the more the fifth moment (T 5 ), in which the opening of the second clutch is completed, has to be anticipated with respect to a fourth moment (T 2 ), in which the closure of the first clutch is completed.