Multi-speed transmission
View Patent ↗A transmission is disclosed having an input member, an output member, a plurality of planetary gear sets, a plurality of interconnecting members and a plurality of torque-transmitting mechanisms. The plurality of planetary gear sets has first, second and third members. The input member is continuously interconnected with a member of the planetary gear sets. The output member is continuously interconnected with another member of the planetary gear sets. At least eight forward speeds and one reverse speed are produced by the selective engagement of the five torque-transmitting mechanisms.
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 second member of the second 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 the first member of the second planetary gear set;
a second interconnecting member continuously interconnecting the second member of the first planetary gear set with the third member of the fourth planetary gear set;
a third interconnecting member continuously interconnecting the third member of the second planetary gear set with the first member of the third planetary gear set;
a fourth interconnecting member continuously interconnecting the second member of the third planetary gear set with the second member of the fourth planetary gear set; and
five torque transmitting mechanisms each selectively engageable to interconnect at least one of the first members, the second members, and the third members with at least one other of the first members, the second members, the third members member, and a stationary 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 a first of the five torque-transmitting mechanisms is selectively engageable to interconnect the first member of the first planetary gear set with the stationary member.
3. The transmission of claim 1 wherein a second of the five torque-transmitting mechanisms is selectively engageable to interconnect the third member of the first planetary gear set with the stationary member.
4. The transmission of claim 1 wherein a third of the five torque-transmitting mechanisms is selectively engageable to interconnect the second member of the second planetary gear set with the first member of the fourth planetary gear set.
5. The transmission of claim 1 wherein a fourth of the five torque-transmitting mechanisms is selectively engageable to interconnect the first member of the third planetary gear set with the first member of the fourth planetary gear set.
6. The transmission of claim 1 wherein a fifth of the five torque-transmitting mechanisms is selectively engageable to interconnect the third member of the third planetary gear set with the first member of the fourth planetary gear set.
7. The transmission of claim 1 wherein the first, second, and third members of the first, second, third, and fourth planetary gear sets are each at least one of a sun gear, a ring gear, and a carrier member.
8. 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.
9. 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, and the output member is continuously interconnected with the carrier member of the fourth 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 carrier member of the first planetary gear set with the 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 sun gear of the third planetary gear set;
a fourth interconnecting member continuously interconnecting the carrier member of the third planetary gear set with the planet gear carrier of the fourth planetary gear set; and
five torque transmitting mechanisms each selectively engageable to interconnect at least one of the sun gears, carrier members, and ring gears with at least one other of the sun gears, ring gears, carrier members, and a stationary 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.
10. The transmission of claim 9 wherein the five torque-transmitting mechanisms include two brakes connected to the first planetary gear set and three clutches connected to the second, third, and fourth planetary gear sets.
11. The transmission of claim 9 wherein a first of the torque-transmitting mechanisms is operable to selectively connect the first planetary gear set to the stationary member.
12. The transmission of claim 9 wherein a second of the torque-transmitting mechanisms is operable to selectively connect the first planetary gear set and the second planetary gear set to the stationary member.
13. The transmission of claim 9 wherein a third of the torque-transmitting mechanisms is operable to selectively connect the second planetary gear set and the input member to the fourth planetary gear set.
14. The transmission of claim 9 wherein a fourth of the torque-transmitting mechanisms is operable to selectively connect the second planetary gear set and the third planetary gear set to the fourth planetary gear set.
15. The transmission of claim 9 wherein a fifth of the torque-transmitting mechanisms is operable to selectively connect the third planetary gear set to the fourth planetary gear set.
16. 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, and the output member is continuously interconnected with the carrier member of the fourth planetary gear set;
a first torque-transmitting mechanism selectively engageable to interconnect the sun gear of the first and second planetary gear sets with a stationary member;
a second torque-transmitting mechanism selectively engageable to interconnect the ring gear of the first planetary gear set with the stationary member;
a third torque-transmitting mechanism selectively engageable to interconnect the carrier member of the second planetary gear set with the sun gear of the fourth planetary gear set;
a fourth torque-transmitting mechanism selectively engageable to interconnect the sun gear of the third planetary gear set with the sun gear of the fourth planetary gear set; and
a fifth torque-transmitting mechanism selectively engageable to interconnect the ring gear of the third planetary gear set with the sun gear of the fourth planetary gear set, 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.
17. The transmission of claim 16 wherein the sun gear of the first planetary gear set is fixedly connected with the sun gear of the second planetary gear set.
18. The transmission of claim 17 further comprising 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.
19. The transmission of claim 16 wherein the carrier member of the first planetary gear set is fixedly connected with the ring gear of the fourth planetary gear set.
20. The transmission of claim 19 further comprising a second interconnecting member continuously interconnecting the carrier member of the first planetary gear set with the ring gear of the fourth planetary gear set.
21. The transmission of claim 16 wherein the ring gear of the second planetary gear set is fixedly connected with the sun gear of the third planetary gear set.
22. The transmission of claim 21 further comprising a third interconnecting member continuously interconnecting the ring gear of the second planetary gear set with the sun gear of the third planetary gear set.
23. The transmission of claim 16 wherein the carrier member of the third planetary gear set is fixedly connected with the carrier member of the fourth planetary gear set.
24. The transmission of claim 23 further comprising a fourth interconnecting member continuously interconnecting the carrier member of the third planetary gear set with the carrier member of the fourth planetary gear set.