Patent · US Expired

Process and apparatus for suppressing external load carrying wing flutter for aircraft

US4502652A · kind A · utility

21Cited by
3References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 9, 1982
Grant dateMar 5, 1985
Priority date
Expiry dateSep 9, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S416/50
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

In a semi-active system for suppressing external load-carrying wing flutter in aircraft, the carrying wing (1) is provided with one or more external loads (2), and the suspension of the external load (2) on the carrying wing (1) about an axis is arranged at right angles to the plane of symmetry of the aircraft. The external load (2) is mounted to pivot about the axis (3). A spring is provided between the carrying wing (1) and the external load (2); however, it is constructed, to take up the stationary and quasi-stationary moments, as a linear spring (7) with relatively great stiffness and permitting only small spring excursions. A further spring (8) is arranged in parallel with spring (7) and is constructed to be nonlinear and also to have negative stiffness and passage through zero in the region of the negative stiffness. The springs (7 and 8) form a spring system of small stiffness in and about the operating point defined by the passage through zero of the nonlinear spring (8) and the stationary moments. The operating point of the nonlinear spring (8) is slaved in each equilibrium position between the carrying wing (1) and external load (2).

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