Dual-clutch transmission

Patent metadata

Field	Value
Publication number	US-9752654-B2
Application number	US-201314376201-A
Country	US
Kind code	B2
Filing date	Jan 10, 2013
Priority date	Feb 2, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A dual-clutch transmission has two input shafts for connection to a power shift clutch, at least one countershaft offset in parallel to the input shafts, an output gearwheel designed as an idler gear and situated coaxially with respect to the countershaft, at least one gearwheel plane having an idler gear situated coaxially with respect to the countershaft, and a shifting unit having a first shift position in which the output gearwheel and the countershaft are connected to one another in a rotationally fixed manner. The shifting unit has a second shift position in which the idler gear and the output gearwheel are directly connected to one another in a rotationally fixed manner.

First claim

The invention claimed is:

1. A dual-clutch transmission, comprising:
a power shift clutch;
two input shafts configured for connection to the power shift clutch;
at least one countershaft that is offset in parallel to the two input shafts;
an output gearwheel which is configured as a first idler gear and situated coaxially with respect to the at least one countershaft;
a first gearwheel plane having a second idler gear that is situated coaxially with respect to the at least one countershaft;
a shifting unit having a first shift position in which the output gearwheel and the at least one countershaft are connected to one another in a rotationally fixed manner, wherein the shifting unit has a second shift position in which the second idler gear and the output gearwheel are directly connected to one another in a rotationally fixed manner;
at least one additional gearwheel plane, which in at least one forward gear ratio or at least one reverse gear ratio is provided together with the first gearwheel plane for transmitting a force flow or power flow,
wherein the dual-clutch transmission has a total of five gearwheel planes each connecting one of the input shafts to the at least one countershaft and a total of five shifting units maximum for shifting at least eight forward gear ratios and at least one reverse gear ratio.

2. The dual-clutch transmission of claim 1 , wherein the shifting unit has a synchronizing element permanently connected to the output gearwheel in a rotationally fixed manner.

3. The dual-clutch transmission of claim 2 , wherein the second idler gear is situated in an axial direction between the synchronizing element and the output gearwheel.

4. The dual-clutch transmission of claim 2 , wherein the second idler gear is rotatably mounted on the output gearwheel or the synchronizing element.

5. The dual-clutch transmission of claim 1 , wherein the shifting unit has a coupling element permanently connected to the countershaft in a rotationally fixed manner, and a coupling element permanently connected to the second idler gear in a rotationally fixed manner.

6. The dual-clutch transmission of claim 5 , wherein one of the at least one additional gearwheel planes has a third idler gear situated coaxially with respect to the at least one countershaft, and the shifting unit has an additional coupling element permanently connected to the third idler gear in a rotationally fixed manner.

7. The dual-clutch transmission of claim 1 , wherein the shifting unit has three shift positions and one neutral position.

8. The dual-clutch transmission of claim 1 , wherein all gearwheel planes have a fixed gear permanently connected to one of the input shafts in a rotationally fixed manner.

9. The dual-clutch transmission of claim 1 , further comprising:
an additional countershaft offset in parallel to the at least one countershaft and the input shafts; and
an output gearwheel permanently connected to the additional countershaft in a rotationally fixed manner.

Assignees

• Daimler Ag

Inventors

• Gitt Carsten

Classifications

• F16H2003/0826

  wherein at least one gear on the input shaft, or on a countershaft is used for two different forward gear ratios · CPC title

• F16H2200/006

  the gear ratios comprising eight forward speeds · CPC title

• F16H3/08 Primary

  exclusively or essentially with continuously meshing gears, that can be disengaged from their shafts · CPC title

• Y10T74/19228

  Multiple concentric clutch shafts · CPC title

• F16H2003/0931

  each countershaft having an output gear meshing with a single common gear on the output shaft · CPC title