Hingeless helicopter rotor with improved stability
Rotor without flapping hinges and without lead-lag hinges
Multi-blade propellers Patent #: 4281966
ApplicationNo. 06/143628 filed on 04/25/1980
US Classes:416/141, Plural articulation416/134AAircraft rotors
ExaminersPrimary: Powell, Everette A. Jr.
Attorney, Agent or Firm
International ClassesB64C 27/32 (20060101)
B64C 27/33 (20060101)
Foreign Application Priority Data1979-05-16 DE
AbstractThe wing blades of a hingeless and bearingless multiblade rotor are connected to a substantially rigid rotor hub by spar sections elastically twistable and bendable in the flapping direction and in the lead-lag direction. The mounting positions on the periphery of the rotor hub for connection of the spar sections of the respective blades are off-set relative to the angular position of the corresponding blades to which they are connected. Further, the mounting positions for the spar sections of each rotor blade are situated on the periphery of the half side or far side of the rotor hub, facing away from the respective rotor blade. A rear spar section of each mounted rotor blade with reference to the direction of rotation, overlaps the front spar section of the immediately following rotor blade but with free clearance and spacing between the overlapping spar sections in the direction of the rotor axis so that the maximum bendable length of the elastic spar sections is afforded without interference between the blades. The effective or virtual flapping hinges and lead-lag hinges of each blade is shifted closer to the rotor axis thereby minimizing the masses necessary for propeller moment compensation, and static and dynamic balancing of the rotor blades, as well as reducing the required steering forces.