Multi-speed transmission
View Patent ↗A transmission is provided having an input member, an output member, four planetary gear sets each having a first, a second, and a third members, 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 are each selectively engageable to interconnect at least one of the first, second, 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. 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.
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 member;
a second interconnecting member continuously interconnecting the first member of the second planetary gear set with the first member of the first planetary gear set;
a third interconnecting member continuously interconnecting the second member of the first planetary gear set with the first member of the fourth planetary gear set;
a fourth interconnecting member continuously interconnecting the third member of the first planetary gear set with the second member of the second planetary gear set;
a fifth interconnecting member continuously interconnecting the second member of the second planetary gear set with the first member of the third planetary gear set; and
five torque transmitting devices each selectively engageable to interconnect at least one of the first, second, 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 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.
2. The transmission of claim 1 wherein a first of the five torque transmitting devices is selectively engageable to interconnect the third member of the third planetary gear set with at least one of the second 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 devices is selectively engageable to interconnect the third member of the third planetary gear set with at least one of the third member of the fourth planetary gear set and the input member.
4. The transmission of claim 3 wherein a third of the five torque transmitting devices is selectively engageable to interconnect the second member of the third planetary gear set with at least one of the third member of the fourth planetary gear set and the input member.
5. The transmission of claim 4 wherein a fourth of the five torque transmitting devices is selectively engageable to interconnect the third member of the second planetary gear set with the third member of the third planetary gear set.
6. The transmission of claim 5 wherein a fifth of the five torque transmitting devices is selectively engageable to interconnect at least one of the first member of the second planetary gear set, the first member of the first planetary gear set and the stationary member with the second member of the third planetary gear set.
7. The transmission of claim 1 wherein the first members of the first and second planetary gear sets and third members of the third and fourth planetary gear sets are sun gears, the second members of the first, second and fourth planetary gear sets and first member of the third planetary gear set are carrier members and the third members of the first and second planetary gear sets, second member of the third planetary gear set, the first member of the fourth planetary gear set are ring gears.
8. The transmission of claim 1 wherein the input member is continuously interconnected with the third member of the fourth planetary gear set and wherein the output member is continuously interconnected with the second member of the fourth planetary gear set.
9. The transmission of claim 1 wherein four of the torque transmitting devices are clutches and one of the torque transmitting devices is a brake.
10. The transmission of claim 1 wherein the stationary member 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 third member of the fourth planetary gear set and wherein 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 a stationary member;
a second interconnecting member continuously interconnecting the first member of the second planetary gear set with the first member of the first planetary gear set;
a third interconnecting member continuously interconnecting the second member of the first planetary gear set with the first member of the fourth planetary gear set;
a fourth interconnecting member continuously interconnecting the third member of the first planetary gear set with the second member of the second planetary gear set;
a fifth interconnecting member continuously interconnecting the second member of the second planetary gear set with the first member of the third planetary gear set; and
a first torque transmitting device selectively engageable to interconnect the third member of the third planetary gear set with at least one of the second member of the fourth planetary gear set and the output member;
a second torque transmitting device selectively engageable to interconnect the third member of the third planetary gear set with at least one of the third member of the fourth planetary gear set and the input member;
a third torque transmitting device selectively engageable to interconnect the second member of the third planetary gear set with at least one of the third member of the fourth planetary gear set and the input member;
a fourth torque transmitting device selectively engageable to interconnect the third member of the second planetary gear set with the third member of the third planetary gear set; and
a fifth torque transmitting device selectively engageable to interconnect at least one of the first member of the second planetary gear set, the first member of the first planetary gear set and the stationary member with the second member of the third planetary gear set, 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.
12. The transmission of claim 11 wherein the first members of the first and second planetary gear sets and third members of the third and fourth planetary gear sets are sun gears, the second members of the first, second and fourth planetary gear sets and first member of the third planetary gear set are carrier members and the third members of the first and second planetary gear sets, second member of the third planetary gear set, the first member of the fourth planetary gear set are ring gears.
13. The transmission of claim 11 wherein the stationary member 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 sun gear of the fourth planetary gear set and wherein 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 a stationary member;
a second interconnecting member continuously interconnecting the sun gear of the second planetary gear set with the sun gear of the first planetary gear set;
a third interconnecting member continuously interconnecting the carrier member of the first planetary gear set with the ring gear of the fourth planetary gear set;
a fourth interconnecting member continuously interconnecting the ring gear of the first planetary gear set with the carrier member of the second planetary gear set;
a fifth interconnecting member continuously interconnecting the carrier member of the second planetary gear set with the carrier member of the third planetary gear set;
a first torque transmitting device selectively engageable to interconnect the sun gear of the third planetary gear set with at least one of the carrier member of the fourth planetary gear set and the output member;
a second torque transmitting device selectively engageable to interconnect the sun gear of the third planetary gear set with at least one of the sun gear of the fourth planetary gear set and the input member;
a third torque transmitting device selectively engageable to interconnect the ring gear of the third planetary gear set with at least one of the sun gear of the fourth planetary gear set and the input member;
a fourth torque transmitting device selectively engageable to interconnect the ring gear of the second planetary gear set with the sun gear of the third planetary gear set; and
a fifth torque transmitting device selectively engageable to interconnect at least one of the sun gear of the second planetary gear set, the sun gear of the first planetary gear set and the stationary member with the ring gear of the third planetary gear set, 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.
15. The transmission of claim 14 wherein the stationary member is a transmission housing.