MULTI-SPEED TRANSMISSION

• US 20090054193A1
• Filed: 03/05/2008
• Published: 02/26/2009
• Est. Priority Date: 08/21/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Hart, James M., Phillips, Andrew W., Wittkopp, Scott H., CAREY, CLINTON E.
• Granted Patent: US 7,896,773 B2
• Time in Patent Office: Days
• US Class Current: 475/276
• 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 include clutches.

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 interconnecting member continuously interconnecting the first member of the first planetary gear set with a stationary element;

a second interconnecting member continuously interconnecting the third member of the second planetary gear set with the stationary element;

a third interconnecting member continuously interconnecting the third member of the first planetary gear set with the first member of the third planetary gear set;

a fourth interconnecting member continuously interconnecting the first member of the second planetary gear set with the third member of the third planetary gear set and the first member of the fourth planetary gear set; and

five torque transmitting mechanisms selectively engageable to interconnect one of the first, second, and third members with at least one of the first, second, and third members, and

wherein the torque transmitting mechanisms are selectively engageable in combinations of at least two 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 a first of the five torque transmitting mechanisms is selectively engageable to interconnect the second member of the second planetary gear set with at least one of the third member of the fourth planetary gear set and the output member.

3. The transmission of claim 2 wherein a second of the five torque transmitting mechanisms is selectively engageable to interconnect at least one of the second member of the first planetary gear set and the input member with at least one of the third member of the third planetary gear set, the first member of the second planetary gear set, and the first member of the fourth planetary gear set.

4. The transmission of claim 3 wherein a third of the five torque transmitting mechanisms is selectively engageable to interconnect the second member of the fourth planetary gear set with at least one of the second member of the first planetary gear set and the input member.

5. The transmission of claim 4 wherein a fourth of the five torque transmitting mechanisms is selectively engageable to interconnect at least one of the third member of the first planetary gear set and the first member of the third planetary gear set with at least one of the third member of the third planetary gear set, the first member of the second planetary gear set, and the first member of the fourth planetary gear set.

6. The transmission of claim 5 wherein a fifth of the five torque transmitting mechanisms is selectively engageable to interconnect the second member of the third planetary gear set with the second member of the fourth planetary gear set.

7. 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.

8. The transmission of claim 1 wherein the input member is continuously interconnected with the second member of the first planetary gear set and wherein the output member is continuously interconnected with the third member of the fourth planetary gear set.

9. The transmission of claim 1 wherein the torque transmitting mechanisms are clutches.

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

11. A transmission comprising:

an input member;

an output member;

first, second, third and fourth planetary gear sets each having first, second and third members, wherein the input member is continuously interconnected with the second member of the first planetary gear set and wherein the output member is continuously interconnected with the third member of the fourth planetary gear set;

a first interconnecting member continuously interconnecting the first member of the first planetary gear set with a stationary element;

a second interconnecting member continuously interconnecting the third member of the second planetary gear set with the stationary element;

a third interconnecting member continuously interconnecting the third member of the first planetary gear set with the first member of the third planetary gear set;

a fourth interconnecting member continuously interconnecting the first member of the second planetary gear set with the third member of the third planetary gear set and the first member of the fourth planetary gear set;

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

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

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

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

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

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

12. The transmission of claim 11 wherein the first members are sun gears, the second members are carrier members, and the third members are ring gears.

13. The transmission of claim 11 wherein the stationary element is a transmission housing.

14. 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 first planetary gear set and wherein the output member is continuously interconnected with the ring gear of the fourth planetary gear set;

a first interconnecting member continuously interconnecting the sun gear of the first planetary gear set with a stationary element;

a second interconnecting member continuously interconnecting the ring gear of the second planetary gear set with the stationary element;

a third interconnecting member continuously interconnecting the ring gear of the first planetary gear set with the sun gear of the third planetary gear set;

a fourth interconnecting member continuously interconnecting the sun gear of the second planetary gear set with the ring gear of the third planetary gear set and the sun gear of the fourth planetary gear set;

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

a second torque transmitting mechanism selectively engageable to interconnect at least one of the carrier member of the first planetary gear set and the input member with at least one of the ring gear of the third planetary gear set, the sun gear of the fourth planetary gear set, and the sun gear of the second planetary gear set;

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

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

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

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

15. The transmission of claim 14 wherein the stationary element is a transmission housing.