Patent · US Expired

Rotor blade retention system

US4135856A · kind A · utility

25Cited by
10References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 3, 1977
Grant dateJan 23, 1979
Priority date
Expiry dateFeb 3, 1997

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB64C27/32
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A rotor blade retention system connects an elongated rotor blade to a rotor hub that is rotatable about its central axis. The connected rotor blade normally extends generally radially from the hub and is rotatable with the hub. The retention system includes a pair of bearings that are interconnected in parallel load transmitting relationship. Both bearings are connected in serial load transmitting relationship with a flap hinge. One bearing is relatively stiff along the longitudinal axis of the rotor blade and is less stiff in directions transverse to the longitudinal blade axis. The other bearing is most stiff in directions transverse to the rotor blade axis and is less stiff along the axis. Both bearings define effective elastic centers which are located along the longitudinal blade axis, but the two elastic centers are spaced from each other. The two bearings accommodate lead-lag motions of the rotor blade. Because of the relative stiffnesses of the bearings in directions transverse to the longitudinal axis of the rotor blade, the axis about which lead-lag motion occurs is displaced from the effective elastic center of the bearing that has its greatest stiffness along the longit…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.