Multi-speed dual clutch transmission

Patent metadata

Field	Value
Publication number	US-9453558-B2
Application number	US-201414326049-A
Country	US
Kind code	B2
Filing date	Jul 8, 2014
Priority date	Jul 8, 2014
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

A transmission is connectable to an input member and includes an output transfer gear, first and second transmission input shaft members, first and second countershaft members, first and second sleeve shafts, a plurality of co-planar gear sets, and a plurality of torque transmitting devices. The torque transmitting devices include a plurality of gears, synchronizer assemblies and a dual clutch assembly. The transmission is operable to provide at least one reverse speed ratio and a plurality of forward speed ratios between the input member and the output member.

First claim

The invention claimed is:

1. A transmission comprising:
a transmission housing;
a dual clutch assembly having a first clutch, a second clutch and a clutch housing connectable to an engine output member, wherein the clutch housing is rotationally supported within the transmission housing;
a first, second, third, fourth and fifth gear set, wherein the first gear set includes a first gear in mesh with a second gear, the second gear set includes a first gear in mesh with a third gear and wherein the third gear is in mesh with a second gear, the third gear set includes a first gear in mesh with a third gear and wherein the third gear is in mesh with a second gear, the fourth gear set includes a first gear in mesh with a second gear and a third gear and the fifth gear set includes a first gear in mesh with a second gear;
a first transmission input member rotatably supported in the transmission housing and wherein the first gear of the second gear set is rotatably fixed for common rotation with the first transmission input member and wherein the selective engagement of the first clutch of the dual clutch assembly transfers torque from the clutch housing to the first transmission input member;
a second transmission input member rotatably supported in the transmission housing and wherein the first gear of the third gear set is rotatably fixed for common rotation with the second transmission input member and wherein the second transmission input member is concentric with the first transmission input member and at least partially surrounds the first transmission input member and wherein the selective engagement of the second clutch of the dual clutch assembly transfers torque from the clutch housing to the second transmission input member;
a first countershaft rotatably supported within the transmission housing and spaced apart from and parallel with the first and second transmission input members, wherein the first gear of the first gear set is fixed for common rotation with the first countershaft;
a second countershaft rotatably supported within the transmission housing and spaced apart from and parallel with the first and second transmission input members, wherein the second gear of the first gear set, the third gear of the fourth gear set are each fixed for common rotation with the second countershaft, and wherein the third gear of the second gear set, the third gear of the third gear set are each selectively connectable for common rotation with the second countershaft;
a third countershaft rotatably supported within the transmission housing and spaced apart from and parallel with the first and second transmission input members, wherein the second gear of the fifth gear set is fixed for common rotation with the third countershaft;
a first countershaft transfer gear selectively connectable to the first countershaft for common rotation with the first countershaft;
a second countershaft transfer gear selectively connectable to the third countershaft for common rotation with the third countershaft wherein the first and second countershaft transfer gears transfer torque to a transmission output member;
a first sleeve shaft rotatably supported in the transmission housing and at least partially overlaps the first countershaft and wherein the second gear of the second gear set and the first gear of the fifth gear set are rotatably fixed for common rotation with the first sleeve shaft;
a second sleeve shaft rotatably supported in the transmission housing and at least partially overlaps the first sleeve and wherein the second gear of the third gear set and the second gear of the fourth gear set is rotatably fixed for common rotation with the second sleeve shaft; and
five synchronizer assemblies for selectively coupling at least one of gears of the five gear sets with at least one of the sleeve shafts and the first, second and third countershafts, and
wherein the selective engagement of the first and second clutches of the dual clutch assembly interconnects the dual clutch housing with at least one of the first and the second transmission input members and the selective engagement of at least one of the five synchronizer assemblies establishes at least one of a plurality of forward and reverse speed ratios.

2. The transmission of claim 1 wherein a first of the five synchronizer assemblies selectively connects the first countershaft transfer gear to the first countershaft.

3. The transmission of claim 2 wherein a second of the five synchronizer assemblies selectively connects the second countershaft transfer gear to the third countershaft.

4. The transmission of claim 3 wherein a third of the five synchronizer assemblies selectively connects the second gear of the third gear set to the first sleeve shaft.

5. The transmission of claim 4 wherein a fourth of the five synchronizer assemblies selectively connects the third gear of the second gear set to third gear of the third gear set.

6. The transmission of claim 5 wherein a fifth of the five synchronizer assemblies selectively connects the third gear of the second gear set to the second countershaft.

7. The transmission of claim 1 wherein the fifth gear set is adjacent the dual clutch assembly, the fourth gear set is adjacent the fifth gear set, the third gear set is adjacent the fourth gear set, the second gear set is adjacent the third gear set and the first gear set is disposed between the second gear set and an end wall of the transmission housing.

8. The transmission of claim 1 wherein the five synchronizer assemblies includes a first synchronizer assembly for selectively connecting the first countershaft transfer gear to the first countershaft and a fourth synchronizer assembly for selectively connecting the third of the second gear set to the third of third gear set to establish a first gear ratio when the first clutch of the dual clutch is engaged to connect the dual clutch housing to the first transmission input member.

9. The transmission of claim 1 wherein the five synchronizer assemblies includes a first synchronizer assembly for selectively connecting the first countershaft transfer gear to the first countershaft and a third synchronizer assembly for selectively connecting the second gear of the second gear set to second gear of the third gear set to establish a second gear ratio when the second clutch of the dual clutch is engaged to connect the dual clutch housing to the second transmission input member.

10. The transmission of claim 1 wherein the five synchronizer assemblies includes a first synchronizer assembly for selectively connecting the first countershaft transfer gear to the first countershaft and a third synchronizer assembly for selectively connecting the second gear of the second gear set to second gear of the third gear set to establish a third gear ratio when the first clutch of the dual clutch is engaged to connect the dual clutch housing to the first transmission input member.

11. The transmission of claim 1 wherein the five synchronizer assemblies includes a second synchronizer assembly for selectively connecting the second countershaft transfer gear to the third countershaft and a third synchronizer assembly for selectively connecting the second gear of the second gear set to second gear of the third gear set to establish a fourth gear ratio when the second clutch of the dual clutch is engaged to connect the dual clutch housing to the first transmission input member.

12. The transmission of claim 1 wherein the five synchronizer assemblies includes a second synchronizer assembly for selectively connecting the second countershaft transfer gear to the third countershaft and a fourth synchronizer assembly for s

Assignees

• Gm Global Tech Operations Llc
• Gm Global Tech Operations Llc

Inventors

• Wittkopp Scott H
• Ross Craig S

Classifications

• F16H3/006 Primary

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

• F16H2200/006

  the gear ratios comprising eight forward speeds · CPC title

• F16H57/023 Primary

  Mounting or installation of gears or shafts in the gearboxes, e.g. methods or means for assembly · CPC title

• F16H2200/0052

  the gear ratios comprising six forward speeds · CPC title

• F16H2003/0933

  with coaxial countershafts · CPC title