US 12,128,903 B2
Method and control device for operating a drive train
Mario Steinborn, Friedrichshafen (DE); Maik Würthner, Markdorf (DE); Thea Schlueter, Friedrichshafen (DE); Frieder Norrenberg, Argenbühl (DE); and Martin Fajfr, Štěnovice (CZ)
Assigned to ZF Friedrichshafen AG, Friedrichshafen (DE)
Appl. No. 18/573,639
Filed by ZF Friedrichshafen AG, Friedrichshafen (DE)
PCT Filed Jun. 21, 2022, PCT No. PCT/EP2022/066785
§ 371(c)(1), (2) Date Dec. 22, 2023,
PCT Pub. No. WO2022/268750, PCT Pub. Date Dec. 29, 2022.
Claims priority of application No. 10 2021 206 547.3 (DE), filed on Jun. 24, 2021.
Prior Publication US 2024/0300497 A1, Sep. 12, 2024
Int. Cl. B60W 30/19 (2012.01); B60W 10/02 (2006.01); B60W 10/04 (2006.01); B60W 10/111 (2012.01); F16H 59/18 (2006.01); F16H 59/42 (2006.01); F16H 59/44 (2006.01); F16H 59/54 (2006.01); F16H 61/04 (2006.01); F16H 61/16 (2006.01); F16H 61/70 (2006.01); F16H 59/52 (2006.01); F16H 59/66 (2006.01)
CPC B60W 30/19 (2013.01) [B60W 10/02 (2013.01); B60W 10/04 (2013.01); B60W 10/111 (2013.01); F16H 59/18 (2013.01); F16H 59/42 (2013.01); F16H 59/44 (2013.01); F16H 59/54 (2013.01); F16H 61/0403 (2013.01); F16H 61/16 (2013.01); F16H 61/70 (2013.01); B60W 2510/0638 (2013.01); B60W 2510/104 (2013.01); B60W 2710/021 (2013.01); B60W 2710/1005 (2013.01); F16H 59/52 (2013.01); F16H 2059/663 (2013.01); F16H 2061/0411 (2013.01); F16H 2061/161 (2013.01); F16H 2200/0039 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method for operating a drive-train of a motor vehicle, the method comprising:
providing a drive train comprising a drive aggregate, a drive output, a group transmission connected between the drive aggregate and the drive output, and a separating cutch connected between the drive aggregate and the group transmission, wherein the group transmission comprises a plurality of sub-transmissions that include (i) at least one main transmission and a splitter group drivingly connected upstream from the main transmission and/or (ii) a range group drivingly connected downstream from the main transmission;
determining that a speed of the motor vehicle is lower than a limit value;
opening the separating clutch;
pre-selecting the transmission by changing one of plurality of sub-transmissions to neutral and changing at least one other of the plurality of sub-transmissions to a friction-force-locking condition;
subsequently at least partially closing the separating clutch and bringing the drive aggregate to a pre-defined rotation speed;
determining whether a friction-force-locking group transmission is required;
checking whether a starting shift or a driver-desired shift for the group transmission is called for; and
determining a target rotation speed of the drive aggregate.