Patent · US Active

Magnetorheological fluid elastic lag damper for helicopter rotors

US8413772B2 · kind B2 · utility

4Cited by
7References
17Claims
0Family size

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Key dates

Filing dateFeb 12, 2009
Grant dateApr 9, 2013
Priority date
Expiry dateJul 18, 2031

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16F13/305
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A MagnetoRheological Fluid Elastic (MRFE) lag damper system for adaptive lead-lag damping of helicopter main rotors. Embodiments include snubber dampers especially for hingeless helicopter rotors, and concentric bearing dampers. The snubber lag dampers include a flexible snubber body defining a cavity, a flexible or rigid interior (e.g., center) wall subdividing the cavity, and a flow valve in the interior wall or external to the cavity. The flexible snubber body may comprise elastomeric materials and metal rings stacked together to create a sealed MR fluid cavity. The shear deformation of the snubber body induces MR fluid flow through the valve, controlled by a magnetic field in the valve. An MRFE concentric bearing damper is also disclosed, comprising a pair of concentric tubes with elastomeric material injected and cured in an annular gap between the two tubes, and an MR fluid reservoir with piston-mounted MR valve housed inside the innermost tube.

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