Parallel gearshift transmission of a motor vehicle

Patent metadata

Field	Value
Publication number	US-9945461-B2
Application number	US-201214118711-A
Country	US
Kind code	B2
Filing date	Mar 20, 2012
Priority date	May 24, 2011
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A parallel shift transmission of a motor vehicle comprising splitter and range groups. At least the splitter group is split into two parallel transmission branches having countershafts. One branch can be actuated by a power-shift element to transfer rotation of a drive shaft to a countershaft, via a stepped transmission ratio of the splitter group according to the actuation of one of the transmission branches and then converting and transmitting the rotation, via one of a plurality of range transmission ratios of the range group, to an output shaft. In order to reverse rotation, parallel countershafts can be coupled by individual gearwheel pairs by actuation of associated switching elements such that one countershaft, at the output side of the splitter group in the flow of power flow from the drive to the output shaft, is connected to the other countershaft at a drive side of the range group.

First claim

The invention claimed is:

1. A parallel shift transmission of a motor vehicle comprising:
first and second power-shift elements ( 5 , 6 ),
a splitter group part ( 2 ) and a range group part ( 3 ),
the splitter group part ( 2 ) is split into two parallel transmission branches having countershafts ( 10 , 11 , 14 , 16 ) and the range group part ( 3 ) is split into two parallel transmission branches having countershafts ( 12 , 13 , 15 , 20 , 22 ), the countershafts of the splitter group part are separate from the countershafts of the range group part, at least one of the countershafts of the splitter group part is hollow, and one of the countershafts of the range group part extends completely through the at least one hollow countershaft of the splitter group part,
each one of the transmission branches of the splitter group part is selected by actuating an associated one of the first and the second power-shift elements ( 5 , 6 ) thereby enabling a rotational movement of a drive shaft ( 1 ; 23 ) to be transferred to the respective countershafts ( 10 , 11 ; 14 , 16 ) of the splitter group part at one of a plurality of stepped transmission ratios of the splitter group part ( 2 ) according to selection of one of the transmission branches of the splitter group part and, proceeding therefrom, enabling the rotational movement to be converted into a rotational movement of an output shaft ( 4 ) at one of a plurality of range transmission ratios of the range group part ( 3 ),
each of the stepped transmission ratios is defined by shifting an associated gear step of a plurality of gear steps (A 1 to A 8 ) of the splitter group part ( 2 ), the associated gear steps of the plurality of gear steps of the splitter group part are distributed, in an alternating manner, to the two transmission branches of the splitter group part ( 2 ) in a sequence of the associated stepped transmission ratios,
each of the range transmission ratios is determined by shifting an associated group step of a plurality of group steps (B 1 . 1 to B 3 . 2 ) of the range group part ( 3 ), and
the parallel countershafts ( 10 to 13 ; 12 , 14 , 15 , 16 ; 14 , 16 , 19 to 22 ) of the splitter group part and the range group part are couplable to one another by individual gearwheel pairs (R 1 , R 2 ) according to an actuation of an associated switching element (SR 1 , SR 2 ) in order to effect a rotational direction reversal such that, with respect to a direction of power flow from the drive shaft ( 1 ; 23 ) to the output shaft ( 4 ), an output side of one of the countershafts of the splitter group part ( 2 ) is connected to a drive side of a respective one of the countershafts of the range group part ( 3 ).

2. The parallel shift transmission according to claim 1 , wherein the associated switching element (SR 1 , SR 2 ) is positioned between the respective gearwheel pair (R 1 , R 2 ) and the respective first and the second power-shift elements ( 5 , 6 ) with respect to the direction of the power flow from the drive shaft ( 1 ; 23 ) to the output shaft ( 4 ).

3. The parallel shift transmission according to claim 1 , wherein the respective gearwheel pair (R 1 , R 2 ) is positioned between the respective first and the second power-shift elements ( 5 , 6 ) and the associated switching element (SR 1 , SR 2 ) with respect to the direction of the power flow from the drive shaft ( 1 ; 23 ) to the output shaft ( 4 ).

4. The parallel shift transmission according to claim 1 , wherein the first and the second power-shift elements ( 5 , 6 ) of the transmission branches of the splitter group part are combined in a double clutch ( 7 ), either a first input shaft ( 8 ), to which the plurality of gear steps (A 1 , A 3 , A 5 , A 7 ) of one transmission branch of the splitter group part are coupled, or a second input shaft ( 9 ), to which the plurality of gear steps (A 2 , A 4 , A 6 , A 8 ) of the other transmission branch of the splitter group part are connected, are couplable by the double clutch ( 7 ) to the drive shaft ( 1 ).

5. The parallel shift transmission according to claim 1 , wherein the first and the second power-shift elements ( 5 , 6 ) of the transmission branches are individual clutches ( 17 , 18 ), and each clutch is positioned between countershafts ( 19 , 20 ; 21 , 22 ) of the associated transmission branch.

6. The parallel shift transmission according to claim 5 , wherein the respective individual clutch ( 17 , 18 ) is positioned either between the splitter group part ( 2 ) and the respective gearwheel pair (R 1 , R 2 ) or between the respective gearwheel pair (R 1 , R 2 ) and the range group part ( 3 ) with respect to the direction of the power flow from the drive shaft ( 1 ; 23 ) to the output shaft ( 4 ).

7. The parallel shift transmission according to claim 1 , wherein at least:
the plurality of gear steps having a high stepped transmission ratio are positioned in an axial direction such that each lies individually on an associated plane, or
at least group steps (B 3 . 1 , B 3 . 2 ) having a high range transmission ratio are disposed individually for each transmission branch of the range group part in the axial direction such that each of the group steps (B 3 . 1 , B 3 . 2 ) having the high range transmission ratio lies on an associated plane.

8. The parallel shift transmission according to claim 1 , wherein at least:
the plurality of gear steps (A 1 to A 8 ) are provided in pairs in an axial direction, and each pair lying in a plane, or
at least individual group steps (B 1 . 1 , B 1 . 2 , B 2 . 1 , B 2 . 2 ) are provided for both transmission branches of the range group part in one axial plane in each case.

9. The parallel shift transmission according to claim 1 , wherein a higher gear step is preselected, in an unloaded transmission branch, before actuation of one of the switching elements (SR 1 , SR 2 ) in order to couple the parallel countershafts ( 10 to 13 ; 12 , 14 , 15 , 16 ; 14 , 16 , 19 to 22 ) of the splitter group part and the range group part to one another.

10. The parallel shift transmission according to claim 1 , wherein a gear step is not shifted, in an unloaded transmission branch before actuation of one of the switching elements (SR 1 , SR 2 ), in order to couple the parallel countershafts ( 10 to 13 ; 12 , 14 , 15 , 16 ; 14 , 16 , 19 to 22 ) of the splitter group part and the range group part.

11. A parallel shift transmission for one of an agricultural and a communal commercial vehicle, the parallel shift transmission comprising:
a splitter group portion and a range group portion, and the splitter group portion and the range group portions are both split into two parallel transmission branches which have parallel countershafts, where the countershafts of the splitter group portion are hollow and the countershafts of the range group portion extend completely through the hollow countershafts of the splitter group portion;
each of the two transmission branches is actuated by engagement of a respective first and second power-shift elements such that rotational movement of a drive shaft is transferred to one of the respective countershafts via one of a plurality of stepped transmission ratios of the splitter group portion that are associated with the selected one of the transmission branches, and rotation of the countershaft is converted and transmitted, via one of a plurality of range transmission ratios of the range group portion, to an output shaft of the shift transmission;
each of the stepped transmission ratios of the splitter group portion is a defined by engagement of an associated gear step of a plurality of gear steps of the splitter group portion, the plurality of g

Assignees

• Reisch Matthias
• Beck Stefan
• Fellmann Martin
• Zahnradfabrik Friedrichshafen

Inventors

• Reisch Matthias
• Beck Stefan
• Fellmann Martin

Classifications

• F16H2200/0078

  the gear ratio comprising twelve or more forward speeds · CPC title

• F16H3/093

  with two or more countershafts · CPC title

• F16H2200/0065

  the gear ratios comprising nine forward speeds · CPC title

• Y10T74/19233

  Plurality of counter shafts · CPC title

• F16H2003/0822

  characterised by the arrangement of at least one reverse gear · CPC title