Multi-speed transmission

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, and wherein the input member is continuously connected for common rotation with one of the first, second, and third members of one of the first, second, third, and fourth planetary gear sets;

three interconnecting members continuously interconnecting a member of the first, second, third and fourth planetary gear sets with a member of another of first, second, third and fourth planetary gear sets;

a grounding member for continuously interconnecting at least one of the members of the planetary gear sets to a stationary member; and

six torque transmitting mechanisms wherein four of the six torque transmitting mechanisms are each selectively engageable to interconnect at least one of the first, second and third members of one of the planetary gear sets with a common member, another one of the six torque transmitting mechanisms are each selectively engageable to interconnect at least one of the first, second and third members of one of the planetary gear sets with another of the first, second and third members of another of the planetary gear sets, and wherein yet another one of the six torque transmitting mechanisms are each selectively engageable to interconnect at least one of the first, second and third members of one of the planetary gear sets with the stationary member, and

wherein the six torque transmitting mechanisms are selectively engageable in combinations of at least three to establish a plurality of 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 the three interconnecting members includes a first of the three interconnecting member continuously interconnecting a second member of the first planetary gear set with a third member of the second planetary gear set and a third member of the third planetary gear set, a second of the three interconnecting member continuously interconnecting a second member of the second planetary gear set with a second member of the fourth planetary gear set and a third of the three interconnecting member continuously interconnecting a first member of the third planetary gear set is permanently coupled to a first member of the fourth planetary gear set.

3. The transmission of claim 1 wherein the grounding member interconnects the third member of the first planetary gear set to the stationary member.

4. The transmission of claim 1 wherein a first of the six torque transmitting mechanisms is selectively engageable to interconnect the second member of the third planetary gear set with the common member.

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

6. The transmission of claim 5 wherein a third of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the third planetary gear set and the first member of the fourth planetary gear set with the common member.

7. The transmission of claim 6 wherein a fourth of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the first planetary gear set with the common member.

8. The transmission of claim 7 wherein a fifth of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the first planetary gear set with the second member of the second planetary gear set.

9. The transmission of claim 8 wherein a sixth of the six torque transmitting mechanisms is selectively engageable to interconnect the third member of the fourth planetary gear set with the stationary member.

10. The transmission of claim 1 wherein the input member is continuously connected for common rotation with the second member of the third planetary gear set and the output member is continuously connected for common rotation with the second member of the fourth planetary gear set.

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

12. A transmission comprising:

an input member;

an output member;

first, second, third and fourth planetary gear sets each having first, second and third members, and wherein the input member is continuously connected for common rotation with one of the first, second, and third members of one of the first, second, third, and fourth planetary gear sets;

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

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

a grounding member for continuously interconnecting at least one of the members of the planetary gear sets to a stationary member;

a third interconnecting member continuously interconnecting a first member of the third planetary gear set is permanently coupled to a first member of the fourth planetary gear set; and

six torque transmitting mechanisms each selectively engageable to interconnect at least one of the first, second, and third members of one of the planetary gear sets with at least one other of the first, second, third members of another one of the planetary gear sets, a common member, or the stationary member, and

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

13. The transmission of claim 12 wherein a first of the six torque transmitting mechanisms is selectively engageable to interconnect the second member of the third planetary gear set with the common member.

14. The transmission of claim 13 wherein a second of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the second planetary gear set with the common member.

15. The transmission of claim 14 wherein a third of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the third planetary gear set and the first member of the fourth planetary gear set with the common member.

16. The transmission of claim 15 wherein a fourth of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the first planetary gear set with the common member.

17. The transmission of claim 16 wherein a fifth of the six torque transmitting mechanisms is selectively engageable to interconnect the first member of the first planetary gear set with the second member of the second planetary gear set.

18. The transmission of claim 17 wherein a sixth of the six torque transmitting mechanisms is selectively engageable to interconnect the third member of the fourth planetary gear set with the stationary member.

19. The transmission of claim 12 wherein the grounding member interconnects the third member of the first planetary gear set to the stationary member.

20. The transmission of claim 12 wherein the input member is continuously connected for common rotation with the second member of the third planetary gear set and the output member is continuously connected for common rotation with the second member of the fourth planetary gear set.

21. The transmission of claim 12 wherein the third member of the first planetary gear set, the third member of the second planetary gear set, the first member of the third planetary gear set and the first member of the fourth planetary gear set are sun gears, the second members of the first, second, third and fourth planetary gear sets are carrier members and the first member of the first planetary gear set, the first member of the second planetary gear set, the third member of the third planetary gear set and the third member of the fourth planetary gear set are ring gears.

22. 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 connected for common rotation with the carrier member of the third planetary gear set, and wherein the output member is continuously connected for common rotation with the carrier member of the fourth planetary gear set;

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

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

a third interconnecting member continuously interconnecting the sun gear of the third planetary gear set is permanently coupled to the sun gear of the fourth planetary gear set;

a grounding member for continuously interconnecting the sun gear of the first planetary gear set to a stationary member;

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

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

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

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

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

a sixth torque transmitting mechanism selectively engageable to interconnect the ring gear of the fourth planetary gear set with the stationary member, and

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