Multi-speed transmission

• US 8,157,695 B2
• Filed: 03/31/2008
• Issued: 04/17/2012
• Est. Priority Date: 04/20/2007
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Phillips, Andrew W., Wittkopp, Scott H., Carey, Clinton E., Hart, James M.
• Primary Examiner(s): Le, David D
• Assistant Examiner(s): Bishop, Erin D
• Application Number:
  US12/059,270
• Publication Number:
  US 20080261765A1
• Time in Patent Office: 1,478 Days
• Field of Search: 475/278
• 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
• CPC Class Codes: F16H 3/666 with compound planetary gear units, e.g. two intermeshing orbital gears F16H3/663 takes precedence

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. The torque transmitting devices 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.

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 input member is continuously interconnected with the third member of the first planetary gear set;

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

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

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

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

five torque transmitting devices each selectively engageable to interconnect at least one of the first members, second members, and third members of the planetary gear sets with at least one other of the first members, second members, third members of the planetary gear sets, and a stationary member; and

wherein a first of the five torque transmitting devices is selectively engageable to interconnect the second member of the third planetary gear set with the second member of the fourth planetary gear set and the torque transmitting devices 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 second of the five torque transmitting devices is selectively engageable to interconnect the second member of the third planetary gear set with the third member of the fourth planetary gear set.

3. The transmission of claim 2 wherein a third of the five torque transmitting devices is selectively engageable to interconnect the third member of the third planetary gear set with the stationary member.

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

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

6. The transmission of claim 1 wherein the third members of the first, second, third and fourth planetary gear sets are sun gears, the second members of the first, second, third and fourth planetary gear sets are carrier members and the first members of the first, second, third and fourth planetary gear sets are ring gears.

7. The transmission of claim 1 wherein the output member is continuously interconnected with the second member of the fourth planetary gear set.

8. The transmission of claim 1 wherein the stationary member is a transmission housing.

9. 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 third member of the first planetary gear set and the output member is continuously interconnected with the second member of the fourth planetary gear set;

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

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

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

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

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

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

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

a fourth torque transmitting device selectively engageable to interconnect the third member of the fourth planetary gear set with the stationary member; and

a fifth torque transmitting device selectively engageable to interconnect the second member of the second planetary gear set with the stationary member, and

wherein the torque transmitting devices 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.

10. The transmission of claim 9 wherein the third members of the first, second, third and fourth planetary gear sets are sun gears, the second members of the first, second, third and fourth planetary gear sets are carrier members and the first members of the first, second, third and fourth planetary gear sets are ring gears.

11. The transmission of claim 9 wherein the stationary member is a transmission housing.

12. 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 sun gear of the first planetary gear set and the output member is continuously interconnected with the carrier member of the fourth planetary gear set;

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

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

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

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

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

a second torque transmitting device selectively engageable to interconnect the carrier member of the third planetary gear set with the sun gear of the fourth planetary gear set;

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

a fourth torque transmitting device selectively engageable to interconnect the sun gear of the fourth planetary gear set with the stationary member; and

a fifth torque transmitting device selectively engageable to interconnect the carrier member of the second planetary gear set with the stationary member, and

wherein the torque transmitting devices 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.