MULTI-SPEED TRANSMISSION

• US 20110059823A1
• Filed: 11/10/2010
• Published: 03/10/2011
• Est. Priority Date: 04/19/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Hart, James M., Carey, Clinton E., Phillips, Andrew W., Wittkopp, Scott H.
• Granted Patent: US 8,066,610 B2
• Time in Patent Office: Days
• US Class Current: 475/296
• CPC Class Codes: F16H 2200/006 the gear ratios comprising eight forward speeds
• CPC Class Codes: F16H 2200/2012 with four sets of orbital gears
• CPC Class Codes: F16H 2200/2043 with five engaging means
• CPC Class Codes: F16H 2200/2097 comprising an orbital gear set member permanently connected to the housing, e.g. a sun wheel permanently connected to the housing
• CPC Class Codes: F16H 3/66 composed of a number of gear trains without drive passing from one train to another

Abstract

A transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices may include clutches and at least one brake.

Claims

1. A transmission comprising:

an input member;

an output member;

first, second, third and fourth planetary gear sets each having first, second and third members;

a first torque transmitting mechanism selectively engageable to interconnect the first member of the first planetary gear set with a stationary element;

a second torque transmitting mechanism selectively engageable to interconnect the second member of the second planetary gear set with the third member of the third planetary gear set;

a third torque transmitting mechanism selectively engageable to interconnect at least one of the third member of the second planetary gear set and the first member of the third planetary gear set with the third member of the third planetary gear set;

a fourth torque transmitting mechanism selectively engageable to interconnect the second member of the third planetary gear set with the output member; and

a fifth torque transmitting mechanism selectively engageable to interconnect the second member of the fourth planetary gear set with the output member, and

wherein the torque transmitting mechanisms are selectively engageable in combinations of at least three to establish at least eight forward speed ratios and at least one reverse speed ratio between the input member and the output member.

2. The transmission of claim 1 wherein the first members are sun gears, the second members are carrier members, and the third members are ring gears.

3. The transmission of claim 1 wherein the input member is continuously interconnected with the second member of the second planetary gear set.

4. The transmission of claim 1 wherein the stationary element is a transmission housing.

5. The transmission of claim 1 wherein the at least one reverse speed ratio is achieved by engagement of the third, fourth, and fifth torque transmitting mechanisms.

6. The transmission of claim 5 wherein a first of the at least eight forward speed ratios is achieved by engagement of the first, fourth, and fifth torque transmitting mechanisms.

7. The transmission of claim 6 wherein a second of the at least eight forward speed ratios is achieved by engagement of the second, fourth, and fifth torque transmitting mechanisms.

8. The transmission of claim 7 wherein a third of the at least eight forward speed ratios is achieved by engagement of the first, second, and fourth torque transmitting mechanisms.

9. The transmission of claim 8 wherein a fourth of the at least eight forward speed ratios is achieved by engagement of the second, third, and fourth torque transmitting mechanisms.

10. The transmission of claim 9 wherein a fifth of the at least eight forward speed ratios is achieved by engagement of the first, third, and fourth torque transmitting mechanisms.

11. The transmission of claim 10 wherein a sixth of the at least eight forward speed ratios is achieved by engagement of the first, second, and third torque transmitting mechanisms.

12. The transmission of claim 11 wherein a seventh of the at least eight forward speed ratios is achieved by engagement of the first, third, and fifth torque transmitting mechanisms.

13. The transmission of claim 12 wherein an eighth of the at least eight forward speed ratios is achieved by engagement of the second, third, and fifth torque transmitting mechanisms.

14. The transmission of claim 1 wherein the third member of the first planetary gear set and the stationary element form a non-rotary member, the second member of the first planetary gear set and the third member of the fourth planetary gear set form a first rotary member, the first member of the first planetary gear set and the first member of the second planetary gear set form a second rotary member, the third member of the second planetary gear set and the first member of the third planetary gear set form a third rotary member, and the third member of the third planetary gear set and the first member of the fourth planetary gear set form fourth rotary member.

15. A transmission comprising:

an input member;

an output member;

first, second, third and fourth planetary gear sets each having a sun gear, a carrier member, and a ring gear wherein the input member is continuously interconnected with the carrier member of the second planetary gear set;

at least five continuous interconnections from at least one of the sun gears, carrier members, and ring gears to at least one other of the sun gears, carrier members, ring gears, and a stationary member;

a first torque transmitting mechanism selectively engageable to interconnect the sun gear of the first planetary gear set with the stationary member;

a second torque transmitting mechanism selectively engageable to interconnect the carrier member of the second planetary gear set with the ring gear of the third planetary gear set;

a third torque transmitting mechanism selectively engageable to interconnect at least one of the ring gear of the second planetary gear set and the sun gear of the third planetary gear set with the ring gear of the third planetary gear set;

a fourth torque transmitting mechanism selectively engageable to interconnect the carrier member of the third planetary gear set with the output member; and

a fifth torque transmitting mechanism selectively engageable to interconnect the carrier member of the fourth planetary gear set with the output member, and

wherein the torque transmitting mechanisms are selectively engageable in combinations of at least three to establish at least eight forward speed ratios and at least one reverse speed ratio between the input member and the output member.

16. The transmission of claim 15 wherein a first of the five interconnecting members continuously interconnects the ring gear of the first planetary gear set with the stationary member, a second of the five interconnecting members continuously interconnects the carrier member of the first planetary gear set with the ring gear of the fourth planetary gear set, a third of the five interconnecting members continuously interconnects the sun gear of the first planetary gear set with the sun gear of the second planetary gear set, a fourth of the five interconnecting members continuously interconnects the ring gear of the second planetary gear set with the sun gear of the third planetary gear set, and a fifth of the five interconnecting members continuously interconnects the ring gear of the third planetary gear set with the sun gear of the fourth planetary gear set.

17. The transmission of claim 15 wherein the at least one reverse speed ratio is achieved by engagement of the third, fourth, and fifth torque transmitting mechanisms.

18. The transmission of claim 17 wherein a first of the at least eight forward speed ratios is achieved by engagement of the first, fourth, and fifth torque transmitting mechanisms.

19. The transmission of claim 18 wherein a second of the at least eight forward speed ratios is achieved by engagement of the second, fourth, and fifth torque transmitting mechanisms.

20. The transmission of claim 19 wherein a third of the at least eight forward speed ratios is achieved by engagement of the first, second, and fourth torque transmitting mechanisms.

21. The transmission of claim 20 wherein a fourth of the at least eight forward speed ratios is achieved by engagement of the second, third, and fourth torque transmitting mechanisms.

22. The transmission of claim 21 wherein a fifth of the at least eight forward speed ratios is achieved by engagement of the first, third, and fourth torque transmitting mechanisms.

23. The transmission of claim 22 wherein a sixth of the at least eight forward speed ratios is achieved by engagement of the first, second, and third torque transmitting mechanisms.

24. The transmission of claim 23 wherein a seventh of the at least eight forward speed ratios is achieved by engagement of the first, third, and fifth torque transmitting mechanisms.

25. The transmission of claim 24 wherein an eighth of the at least eight forward speed ratios is achieved by engagement of the second, third, and fifth torque transmitting mechanisms.