Multi-speed transmission

• US 7,704,180 B2
• Filed: 12/12/2007
• Issued: 04/27/2010
• Est. Priority Date: 01/11/2007
• 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., Carey, Clinton E., Raghavan, Madhusudan, Phillips, Andrew W., Wittkopp, Scott H.
• Primary Examiner(s): HO, HA DINH
• Application Number:
  US11/954,862
• Publication Number:
  US 20080171628A1
• Time in Patent Office: 867 Days
• Field of Search: 475275-278, 475/284
• US Class Current: 475/275
• 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 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 brakes.

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, wherein the output member is continuously interconnected with the second member of the third planetary gear set;

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

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

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

a fourth interconnecting member continuously interconnecting the second member of the third planetary gear set with the third 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 another of the first, second, third members, and a stationary element, 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 a first of the five torque transmitting mechanisms is selectively engageable to interconnect the second member of the first planetary gear set with the first member of the third planetary gear set.

3. The transmission of claim 2 wherein a second 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 second planetary gear set and the third member of the third planetary gear set.

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

5. The transmission of claim 4 wherein a fourth of the five torque transmitting mechanisms is selectively engageable to interconnect the first member of the second planetary gear set with the stationary element.

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

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.

9. The transmission of claim 1 wherein two of the torque transmitting mechanisms are brakes and three of 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 to the second member of the first planetary gear set and wherein the output member is continuously interconnected to the second member of the third planetary gear set;

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

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

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

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

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

a second 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 second planetary gear set and the third member of the third planetary gear set;

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

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

a fifth torque transmitting mechanism selectively engageable to interconnect the third member of the second planetary gear set with the stationary element, 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.

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 12 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 to the carrier member of the first planetary gear set and wherein the output member is continuously interconnected to the carrier member of the third planetary gear set;

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

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

a third interconnecting member continuously interconnecting the carrier member of the second planetary gear set with the ring gear of the third planetary gear set;

a fourth interconnecting member continuously interconnecting the carrier member of the third planetary gear set with the ring gear of the fourth planetary gear set;

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

a second 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 second planetary gear set and the ring gear of the third planetary gear set;

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

a fourth torque transmitting mechanism selectively engageable to interconnect the sun gear of the second planetary gear set with the stationary element; and

a fifth torque transmitting mechanism selectively engageable to interconnect the ring gear of the second planetary gear set with the stationary element, 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.

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