Helicopter rotor

1. A rotor for a helicopter, comprising:

a drive shaft rotating about a first axis;

a hub angularly integral with said drive shaft about said first axis;

at least two blades projecting from said hub, on the opposite side to said first axis, and extending along respective second axes crosswise to said first axis; each said blade being movable with respect to said hub and the other said blades about a respective fourth axis parallel to said first axis, about the respective said second axis, and about a respective third axis crosswise to said first and respective second axis; and

a number of first dampers for damping vibration associated with at least oscillation of the relative said blades about the respective said fourth axes; said first dampers being connected to one another and each to a relative blade;

said blades rotating, in use, collectively about said first axis together with said hub;

characterized in that at least one said first damper is located between said first axis and said fourth axis of the relative blade, in a radial direction with respect to said first axis;

said rotor further comprising a second damper interposed between said hub and at least one said first damper.

2. A rotor as claimed in claim 1 , characterized in that at least one said blade comprises a connecting member hinged to said hub to move about the respective said second, third, and fourth axis; and a shank defining a radially inner end of the blade with respect to said first axis, and cooperating with the relative said first damper.

3. A rotor as claimed in claim 1 , characterized in that said first dampers define respective arms of a ring surrounding said first axis.

4. A rotor as claimed in claim 1 , characterized in that at least one of said first dampers comprises a tooth engaging a slot defined by said hub.

5. A rotor as claimed in claim 2 , characterized in that each said first damper comprises an elastomeric member fitted through at least partly with said shank of the relative said blade; and a body made of rigid material and defining a cavity housing said elastomeric member.

6. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 1 .

7. A helicopter comprising an antitorque tail rotor; and a main rotor as claimed in claim 1 .

8. A rotor as claimed in claim 2 , characterized in that said first dampers define respective arms of a ring surrounding said first axis.

9. A rotor as claimed in claim 2 , characterized in that at least one of said first dampers comprises a tooth engaging a slot defined by said hub.

10. A rotor as claimed in claim 3 , characterized in that at least one of said first dampers comprises a tooth engaging a slot defined by said hub.

11. A rotor as claimed in claim 6 , characterized in that each said first damper comprises an elastomeric member fitted through at least partly with said shank of the relative said blade; and a body made of rigid material and defining a cavity housing said elastomeric member.

12. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 2 .

13. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 3 .

14. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 4 .

15. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 5 .

16. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 8 .

17. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 9 .

18. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 10 .

19. A helicopter comprising a main rotor; and an antitorque tail rotor as claimed in claim 11 .