Control method for carrying out a gear upshifting in an automatic manual transmission having a dual-clutch gearbox

Control method for carrying out a gear upshifting in an automatic manual transmission having a dual-clutch gearbox to pass from a current shorter gear to a successive longer gear;

• the automatic manual transmission comprises a dual-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:
• receiving a gear shifting command;
• opening a first clutch associated to the current gear;
• closing a second clutch associated to the successive gear in a same first moment;
• finishing the opening of the first clutch associated to the current gear and finishing the closure of the second clutch associated to the successive gear in a same closing moment;
• keeping the rotation speed of the drive shaft constant and equal to an initial value imposed by the gear ratio of the current gear until the closing moment in which the opening of the first clutch is completed;
• decreasing progressively, after the closing moment, the rotation speed of the drive shaft from the initial value imposed by the gear ratio of the current gear to a final value imposed by the gear ratio of the successive gear;
• and
• driving the second clutch after the closing moment for temporarily transmitting to the driving wheels an additional torque, so that the additional torque transmitted by the second clutch determines a progressive reduction of the rotation speed of the drive shaft from the initial value to the final value;
• reducing the torque delivered by the engine after the closing moment to contribute to the progressive reduction of the rotation speed of the drive shaft from the initial value to the final value;
• and
• determining a desired drive style.