Control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox

A control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox, so as to shift from a current gear to a following gear;

• the transmission comprises the dual-clutch gearbox having two primary shafts, at least one secondary shaft connected to drive 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-shift command;
• opening a first clutch associated with the current gear;
• closing a second clutch associated with the following gear;
• in case of downshifting, controlling the second clutch after the complete closing of the second clutch so as to allow said second clutch to temporarily transmit a torque that is greater than the torque to be transmitted by the second clutch immediately after the gear shift and greater than the torque transmitted by the first clutch immediately before the gear shift;
• and
• in case of downshifting, not activating the engine to generate a torque after the complete opening of the first clutch and before the complete closing of the second clutch.

A control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox, so as to shift from a current gear to a following gear;

• the transmission comprises the dual-clutch gearbox having two primary shafts, at least one secondary shaft connected to drive 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-shift command;
• opening a first clutch associated with the current gear;
• closing a second clutch associated with the following gear;
• in case of downshifting, controlling the second clutch after the complete closing of the second clutch so as to allow said second clutch to temporarily transmit a torque that is greater than the torque to be transmitted by the second clutch immediately after the gear shift and greater than the torque transmitted by the first clutch immediately before the gear shift;
• determining whether a driving style is a comfort driving style, an energy efficiency driving style, a sports driving style or a racing driving style;
• in case of upshifting, adjusting the torque (TE) generated by the engine after the complete opening of the first clutch, so as to synchronize the speed (ωE) of rotation of the drive shaft with the speed (ωB) of rotation imposed by the gear ratio of the following gear;
• and
• in case of upshifting, causing the engine to operate in cut-off during the synchronization between the speed (ωE) of rotation of the drive shaft and the speed (ωB) of rotation imposed by the gear ratio of the following gear, only in case of sports or racing driving style.

A control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox, so as to shift from a current gear to a following gear;

• the transmission comprises the dual-clutch gearbox having two primary shafts, at least one secondary shaft connected to drive 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-shift command;
• opening a first clutch associated with the current gear;
• closing a second clutch associated with the following gear;
• in case of downshifting, controlling the second clutch after the complete closing of the second clutch so as to allow said second clutch to temporarily transmit a torque that is greater than the torque to be transmitted by the second clutch immediately after the gear shift and greater than the torque transmitted by the first clutch immediately before the gear shift
• determining whether a driving style is a comfort driving style, an energy efficiency driving style, a sports driving style or a racing driving style;
• and
• in case of upshifting, partially opening the first clutch in advance of the closing of the second clutch, only in case of sports or racing driving style.

A control method for carrying out a gear shift in a transmission provided with a dual-clutch gearbox, so as to shift from a current gear to a following gear;

• the transmission comprises the dual-clutch gearbox having two primary shafts, at least one secondary shaft connected to drive wheels, and two clutches, each of which is interposed between a drive shaft of an engine and a corresponding primary shaft;
• the clutches are in an oil bath and are pressure-controlled, namely the degree of opening/closing of each clutch is determined by the pressure of the oil on the inside of said clutch;
• the control method comprises the steps of:
• receiving a gear-shift command;
• opening a first clutch associated with the current gear;
• closing a second clutch associated with the following gear;
• in case of downshifting, controlling the second clutch after the complete closing of the second clutch so as to allow said second clutch to temporarily transmit a torque that is greater than the torque to be transmitted by the second clutch immediately after the gear shift and greater than the torque transmitted by the first clutch immediately before the gear shift
• filling the second clutch with oil after receiving the gear shift command, by always supplying the greatest possible oil flow rate;
• completely closing the second clutch at the maximum possible speed as soon as the oil filling in said second clutch ends;
• completely opening the first clutch at the maximum possible speed as soon as the oil filling in the second clutch ends;
• determining the oil pressure on the inside of the second clutch;
• and
• establishing that the oil filling in the second clutch has ended when the oil pressure on the inside of the second clutch exceeds a threshold.