US 5,511,944 A · Pitch link for rotary wing aircraft and automatic adjuster thereof

Abstract

A pitch link having an adjustable length is constructed as a diamond-shaped frame by coupling and fixing four flexible beams same in length and rigidity each at end portions thereof. Spherical bearings are provided on opposite ends with the longer diagonal line as an axis of the pitch link. A turnbuckle shaft is screwed into vertex portions on the shorter diagonal line, which is turned so as to adjust a length of the shorter diagonal line, thereby adjusting a length of the pitch link. The turnbuckle shaft is rotated by a detachable motor. Vibrations of a body and the rotational position of a rotor are detected by a vibrosensor and a phase detector respectively while an aircraft equipped with the pitch link is flying, an amount for adjusting the pitch link is calculated by a vibration analyzer from the electrical signals, and the motor is driven through a FM data transmitter/receiver to adjust the pitch link.

Claims20

Dependent claims

A pitch link length automatic adjuster for adjusting a pitch angle of a blade of a rotary wing aircraft comprising:

a vibrosensor for detecting vibrations of a body of the aircraft;
a phase detector for detecting a rotational position of a rotor of the aircraft with respect to a reference position;
a vibration analyzer for calculating a pitch link adjusting amount based on the vibrations and rotor rotational position detected by the vibrosensor and the phase detector, respectively;
an FM data transmitter/receiver converting the calculated pitch link adjusting amount into an electrical signal;
and
pitch link length adjusting means for automatically adjusting a pitch link length based on the electrical signal from the FM data transmitter/receiver.

3 more elements

An automatic adjusting system for adjusting a pitch angle of a blade of a rotary wing aircraft comprising:

an automatic adjuster and an adjustable pitch link operatively connected to the automatic adjuster for adjustment thereby, the automatic adjuster comprising:
a vibrosensor for detecting vibrations of a body of the aircraft;
a phase detector for detecting a rotational position of a rotor of the aircraft with respect to a reference position;
a vibration analyzer for calculating a pitch link adjusting amount based on the vibrations and rotor rotational position detected by the vibrosensor and the phase detector, respectively;
an FM data transmitter/receiver converting the calculated pitch link adjusting amount into an electrical signal;
and
pitch link length adjusting means operatively connected to the adjustable pitch link for automatically adjusting a pitch link length of the pitch link based on the electrical signal from the FM data transmitter/receiver.

4 more elements

Dependencies are inferred from the claim text.

Pitch link for rotary wing aircraft and automatic adjuster thereof

Life of this patent

Pitch link for rotary wing aircraft and automatic adjuster thereof

Life of this patent

Abstract

Claims20