Powertrain for a vehicle and method for carrying out load changes

Patent metadata

Field	Value
Publication number	US-2016017968-A1
Application number	US-201414774224-A
Country	US
Kind code	A1
Filing date	Feb 12, 2014
Priority date	Mar 12, 2013
Publication date	Jan 21, 2016
Grant date	—

Abstract

A drive-train for a vehicle with at least one electric drive, which can be coupled via a driveshaft ( 2 ) to at least a first transmission ratio stage (i 1 ) and a second transmission ratio stage (i 2 ). At least one shifting mechanism is provided for engaging the transmission ratio stages (i 1, i 2 ). To carry out powershifts, the shifting mechanism includes at least one interlocking shifting element ( 5 ) and at least one frictional shifting element ( 6, 6 A). Each of the transmission ratio stages (i 1, i 2 ) can be engaged by the interlocking shifting element ( 5 ) and at least one of the transmission ratio stages (i 2 ) can be engaged both by the interlocking shifting element ( 5 ) and by the frictional shifting element ( 6 ). Methods for carrying out a powershift, between a frictional shifting element ( 6, 6 A) and an interlocking shifting element ( 5 ) in the drive-train, are also disclosed.

First claim

1 - 20 . (canceled)

21 . A drive-train for a vehicle, with at least one electric drive (EM), which is couplable, via a driveshaft, to at least a first transmission ratio stage (i 1 ) and a second transmission ratio stage (i 2 ),
at least one shifting mechanism for engaging the first and the second transmission ratio stages (i 1 , i 2 ), and the at least one shifting mechanism comprising at least one interlocking shifting element ( 5 ) and at least one frictional shifting element ( 6 , 6 A) to carry out powershifts, each of the first and the second transmission ratio stages (i 1 , i 2 ) being engagable by the interlocking shifting element ( 5 ), and at least one of the first and the second transmission ratio stages (i 2 ) is engagable by both of the interlocking shifting element ( 5 ) and the frictional shifting element ( 6 ).

22 . The drive-train according to claim 21 , wherein the first transmission ratio stage (i 1 ) is a first spur gear stage and the second transmission ratio stage (i 2 ) is a second spur gear stage.

23 . The drive-train according to claim 22 , wherein a loose wheel ( 7 ) of the first spur gear stage and a loose wheel ( 8 ) of the second spur gear stage are connectabled to the driveshaft ( 2 ) by the interlocking shifting element ( 5 ), and the loose wheel ( 8 ) of the second spur gear stage is connectable to the driveshaft ( 2 ) by the frictional shifting element ( 6 ).

24 . The drive-train according to claim 22 , wherein a fixed wheel ( 9 ) of the first spur gear stage and a fixed wheel ( 10 ) of the second spur gear stage are connectable, by an intermediate shaft ( 3 ), to a drive output differential ( 4 ).

25 . The drive-train according to claim 22 , wherein a fixed wheel ( 9 ) of the first spur gear stage and a fixed wheel ( 10 ) of the second spur gear stage are connected to the driveshaft ( 2 ),
a loose wheel ( 7 ) of the first spur gear stage and a loose wheel ( 8 ) of the second spur gear stage are connectable, by the interlocking shifting element ( 5 ), to an intermediate shaft ( 3 ), the loose wheel ( 8 ) of the second spur gear stage is connectable, by the frictional shifting element ( 6 ), to the intermediate shaft ( 3 ), and the intermediate shaft ( 3 ) is connected to a drive output differential ( 4 ).

26 . The drive-train according to claim 21 , wherein the first and the second transmission ratio stages (i 1 , i 2 ) are realized by a planetary gearset.

27 . The drive-train according to claim 26 , wherein a sun gear ( 12 ) of the planetary gearset ( 11 ) is connected to the driveshaft ( 2 ), a planetary carrier ( 13 ) is connectable, by the frictional shifting element ( 6 ), to the driveshaft ( 2 ), and
a ring gear ( 15 ) of the planetary gearset ( 11 ) is connectable, by the interlocking shifting element ( 5 ), to either the driveshaft ( 2 ) or a housing ( 16 ).

28 . The drive-train according to claim 27 , wherein a direct drive is engagable via the planetary gearset ( 11 ) by engaging the interlocking shifting element ( 5 ) and the frictional shifting element ( 6 ).

29 . The drive-train according to claim 21 , wherein a preliminary gear ( 1 ) is arranged between the electric drive and the driveshaft ( 2 ).

30 . The drive-train according to claim 21 , wherein the electric drive is an electric machine (EM).

31 . The drive-train according to claim 21 , wherein the frictional shifting element ( 6 ) is a ‘normally open’ disk clutch.

32 . The drive-train according to claim 21 , wherein the interlocking shifting element ( 5 ) is a claw clutch.

33 . A method of carrying out a powershift between a frictional shifting element ( 6 , 6 A) and an interlocking shifting element ( 5 ) in a drive-train with at least one electric drive (EM), which is couplable, via a driveshaft, to at least a first transmission ratio stage (i 1 ) and a second transmission ratio stage (i 2 ), at least one shifting mechanism for engaging the first and the second transmission ratio stages (i 1 , i 2 ), the shifting mechanism comprises at least one of the interlocking shifting element ( 5 ) and at least one of the frictional shifting element ( 6 , 6 A), each of the first and the second transmission ratio stages (i 1 , i 2 ) is engagable by the interlocking shifting element ( 5 ) and at least one of the first and the second transmission ratio stages (i 2 ) is engagable by both of the interlocking shifting element ( 5 ) and the frictional shifting element ( 6 ), the method comprising:
detecting meshing movement, via a path sensor, during a powershift from a closed frictional shifting element ( 6 , 6 A) to an open interlocking shifting element ( 5 ).

34 . The method according to claim 33 , further comprising opening the frictional shifting element ( 6 , 6 A) when, based on the detected meshing movement, complete meshing is recognized.

35 . The method according to claim 33 , further comprising slowly opening the frictional shifting element ( 6 , 6 A) when, based on the detected meshing movement, a tooth-on-tooth position at the interlocking shifting element ( 5 ) is recognized in order to produce a rotational speed difference.

36 . The method according to claim 35 , further comprising, after a rotational speed difference is produced, carrying out closing of the interlocking shifting element ( 5 ) again and opening the frictional shifting element ( 6 , 6 A) when the meshing movement is completed.

37 . The method according to claim 35 , further comprising, as an emergency measure, resolving a tooth-on-tooth position by carrying out a load reduction to allow complete meshing.

38 . The method according to claim 33 , further comprising:
if, on a basis of the detected meshing movement, only partial meshing at the interlocking shifting element ( 5 ) is recognized, again opening the interlocking shifting element ( 5 ) and then partially opening the frictional shifting element ( 6 , 6 A) to produce a slipping condition, and again closing the frictional shifting element ( 6 , 6 A) so that a new orientation is produced, at the interlocking shifting element ( 5 ), in order to resolve a tooth-on-tooth position.

39 . A method of carrying out a powershift between a frictional shifting element ( 6 , 6 A) and an interlocking shifting element ( 5 ) in a drive-train for a vehicle, with at least one electric drive (EM), which is couplable, via a driveshaft, to at least a first transmission ratio stage (i 1 ) and a second transmission ratio stage (i 2 ), at least one shifting mechanism for engaging the first and the second transmission ratio stages (i 1 , i 2 ), the shifting mechanism comprises the interlocking shifting element ( 5 ) and the frictional shifting element ( 6 , 6 A) to carry out powershifts, each of the first and the second transmission ratio stages (i 1 , i 2 ) is engagable by the interlocking shifting element ( 5 ) and at least one of the first and the second transmission ratio stages (i 2 ) is engagable by both of the interlocking shifting element ( 5 ) and the frictional shifting element ( 6 ), the method comprising:
carrying out a powershift depending on at least one of an evaluation of vehicle data and topographical data.

40 . A method of carrying out a powershift between a frictional shifting element ( 6 , 6 A) and an interlocking shifting element ( 5 ) in a drive-train for a vehicle, with at least one electric drive (EM), which is couplable via a driveshaft to at least a first transmission ratio stage (i 1 ) and a second transmission ratio stage (i 2 ), at least one

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Kaltenbach Johannes
• Reisch Matthias
• Kehr Ulrich
• Preuss Michael
• Bornträger Kai

Classifications

• F16H2200/0034

  the gear ratios comprising two forward speeds · CPC title

• F16H2003/0818

  comprising means for power-shifting · CPC title

• F16H2200/2005

  with one sets of orbital gears · CPC title

• F16H2200/2064

  using at least one positive clutch, e.g. dog clutch · CPC title

• F16H2200/2094

  using positive clutches, e.g. dog clutches · CPC title