Dual clutch transmission with a reverse countershaft

Patent metadata

Field	Value
Publication number	US-10883573-B2
Application number	US-201716069543-A
Country	US
Kind code	B2
Filing date	Jan 12, 2017
Priority date	Jan 12, 2016
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

Provided herein is a dual clutch transmission including a reverse countershaft that is selectively engaged with at least one primary shaft and provides speed ratio changes without torque interruption and a compact axial arrangement.

First claim

We claim:

1. A dual clutch transmission, comprising:
an input shaft drivingly connected to an engine;
an output shaft;
a first primary shaft having a plurality of gears rotatably mounted thereon;
a second primary shaft having a plurality of gears rotatably mounted thereon;
a first clutch directly connected to the second primary shaft and drivingly connected to the input shaft;
a second clutch directly connected to the first primary shaft and drivingly connected to the input shaft;
a first countershaft having a plurality of even gears selectively fixed thereto, a plurality of odd gears selectively fixed thereto, a first rigidly fixed gear attached thereto, and a second rigidly fixed gear attached thereto, wherein the plurality of even gears are selectively in driving engagement with the plurality of gears on the first primary shaft, the plurality of odd gears are selectively in driving engagement with the plurality of gears on the second primary shaft, and the first rigidly fixed gear is in driving engagement with the output shaft;
a second countershaft having a plurality of even gears selectively fixed thereto, a plurality of odd gears selectively fixed thereto, and a first rigidly fixed gear attached thereto, wherein the plurality of even gears are selectively in driving engagement with the plurality of gears on the first primary shaft, the plurality of odd gears are selectively in driving engagement with the plurality of gears on the second primary shaft, and the first rigidly fixed gear is in driving engagement with the output shaft; and
a reverse countershaft having a plurality of odd and even gears selectively fixed thereto and a rigidly fixed gear attached thereto and drivingly engaged with the second rigidly fixed gear on the first countershaft,
wherein the odd gears on the reverse countershaft are selectively engaged with the plurality of gears mounted on the first primary shaft and the even gears on the reverse countershaft are selectively engaged with the plurality of gears mounted on the second primary shaft.

2. The dual clutch transmission of claim 1 , wherein the first and second primary shafts are concentric.

3. The dual clutch transmission according to claim 1 , wherein the first and second clutches are concentric clutches.

4. The dual clutch transmission according to claim 1 , wherein the first and second clutches are parallel to each other.

5. The dual clutch transmission according to claim 1 , wherein the second countershaft includes a second rigidly fixed gear, wherein the reverse countershaft includes a second rigidly fixed gear selectively drivingly engaged with the second rigidly fixed gear mounted on the second countershaft.

6. The dual clutch transmission according to claim 1 , wherein the number of gears on the reverse countershaft is less than or equal to half the number of gears on the first and second countershafts.

7. The dual clutch transmission according to claim 1 , wherein the first and second clutches are housed in a clutch housing drivingly connected to the input shaft.

8. The dual clutch transmission of claim 7 , wherein the first clutch is a wet-plate style clutch including a first set of clutch plates directly connected to the clutch housing and a second set of clutch plates directly connected to the second primary shaft and wherein the second clutch is a wet-plate style clutch including a first set of clutch plates directly connected to the clutch housing and a second set of clutch plates directly connected to the first primary shaft.

9. The dual clutch transmission according to claim 1 , further comprising a preselector system for selectively fixing the plurality of even and odd gears to the first countershaft, second countershaft and the reverse countershaft.

10. A dual clutch transmission, comprising:
an input shaft drivingly connected to an engine;
a primary shaft having a plurality of gears rotatably mounted thereto;
a first clutch drivingly engaged with the input shaft and a first countershaft;
a second clutch drivingly engaged with the input shaft and a second countershaft;
a first reverse countershaft;
a second reverse countershaft
wherein the first countershaft has a plurality of odd gears selectively fixed thereto and a rigidly fixed gear attached thereto, wherein the plurality of odd gears are selectively in driving engagement with the plurality of gears on the primary shaft and the rigidly fixed gear is in driving engagement with the first reverse countershaft,
wherein the second countershaft has a plurality of even gears selectively fixed thereto and a rigidly fixed gear attached thereto, wherein the plurality of even gears are in selective driving engagement with the plurality of gears on the primary shaft and the rigidly fixed gear is in driving engagement with the second reverse countershaft,
wherein the first reverse countershaft has a plurality of even gears selectively fixed thereto and in selective driving engagement with the plurality of gears on the primary shaft and a rigidly fixed gear attached thereto drivingly engaged with the rigidly fixed gear on the first countershaft,
wherein the second reverse countershaft has a plurality of odd gears selectively fixed thereto and in selective driving engagement with the plurality of gears on the primary shaft and a rigidly fixed gear attached thereto drivingly engaged with the rigidly fixed gear on the second countershaft.

11. The dual clutch transmission of claim 10 , wherein the number of gears on the first and second reverse countershafts is less than or equal to the number of gears on the first and second countershafts.

12. The dual clutch transmission of claim 10 , wherein the first and second clutches are parallel to each other.

13. The dual clutch transmission of claim 10 , further comprising a first clutch housing and a second clutch housing, wherein the first and second clutch housings are drivingly connected to the input shaft.

14. The dual clutch transmission of claim 10 , further comprising a preselector system for selectively fixing the plurality of even and odd gears to the first countershaft, second countershaft, the first reverse countershaft and the second reverse countershaft.

Assignees

• Dana Belgium Nv

Inventors

• Devreese Thibault G
• Vandevoorde Benoit

Classifications

• F16H2003/0822

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

• F16H2200/006

  the gear ratios comprising eight forward speeds · CPC title

• F16H2200/0095

  the gear ratios comprising four reverse speeds · CPC title

• F16H2200/0091

  the gear ratios comprising three reverse speeds · CPC title

• F16H3/006

  power being selectively transmitted by parallel flow paths, e.g. dual clutch transmissions · CPC title