Shift control method for an automated range-change transmission

A transmission control unit of an automatic range-change transmission for carrying out a method of controlling gear shifting of an automatic range-change transmission which is arranged between a drive engine and a final drive in a drive train of a motor vehicle and includes a multi-stage main transmission having unsynchronized clutches, a two-stage front-mounted group having synchronized clutches and being arranged upstream of the main transmission, and a transmission brake, the method including:

• shifting the main transmission, via the unsynchronized clutches, and shifting the front-mounted group, via the synchronized clutches;
• an upshift in the range-change transmission comprises at least one change of a transmission ratio stage of the front-mounted group, actuating the synchronized clutch of the front-mounted group to synchronize the front-mounted group, intermittently actuating the transmission brake in parallel with actuation of the synchronized clutch of the front-mounted group for supporting the synchronization of the front-mounted group, if a current engine speed of the drive engine is higher than a specified engine speed threshold and based on either a prevailing driving situation or operating situation, and synchronizing the front-mounted group only, via the synchronized clutches of the front-mounted group if the current engine speed of the drive engine is lower than the specified engine speed threshold.

A computer program product having program code that are stored on a computer-readable data carrier for carrying out a method of controlling gear shifting of an automatic range-change transmission which is arranged between a drive engine and a final drive in a drive train of a motor vehicle and includes a multi-stage main transmission having unsynchronized clutches, a two-stage front-mounted group having synchronized clutches and being arranged upstream of the main transmission, and a transmission brake, the method comprising running the computer program product on a transmission control unit of the automatic range-change transmission designed for carrying out the method comprising:

• shifting the main transmission, via the unsynchronized clutches, and B shifting the front-mounted group, via the synchronized clutches;
• an upshift in the range-change transmission comprises at least one change of a transmission ratio stage of the front-mounted group, actuating the synchronized clutch of the front-mounted group to synchronize the front-mounted group, intermittently actuating the transmission brake in parallel with actuation of the synchronized clutch of the front-mounted group for supporting the synchronization of the front-mounted group, if a current engine speed of the drive engine is higher than a specified engine speed threshold and based on either a prevailing driving situation or operating situation, and synchronizing the front-mounted group only via the synchronized clutches of the front-mounted group if the current engine speed of the drive engine is lower than the specified engine speed threshold.