Patent · US Expired

Tail rotor yaw position control for a helicopter

US4759514A · kind A · utility

24Cited by
6References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 30, 1986
Grant dateJul 26, 1988
Priority date
Expiry dateSep 30, 2006

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB64C27/82
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A yaw rate stabilizer for the tail rotor of a helicopter includes a tail rotor shaft rotatably supporting a tail rotor on which rotor blades are radially mounted to develop a lift force directed substantially horizontal and transverse to the longitudinal axis of the aircraft. A slider is provided connected by pitch links to the rotor. The angle of attack of the blades varies with the displacement of the slider relative to a rotor. The rotor shaft is mounted pivotably by a universal joint on the tail of the helicopter fuselage. A frame, pivotably aligned with the universal joint, is supported by a tension or compression spring and connected to a collective pitch transfer lever. The slider, which is slidably mounted on the rotor shaft, moves toward the tail rotor and increases the collective pitch of the blades as a result of the rotor pivoting at the universal joint to precession caused by a transient, yaw moment applied to the rotor by a transverse gust of wind. The blades develop increased lift directed opposite to the gust which opposes the yaw moment and stabilizes the aircraft.

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