Pitch control system

Patent metadata

Field	Value
Publication number	US-10647422-B2
Application number	US-201916410843-A
Country	US
Kind code	B2
Filing date	May 13, 2019
Priority date	Aug 28, 2014
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

A pitch control system configured to vary a pitch angle of at least one of a plurality of propeller blades of a propeller system is provided including a switch movable between a neutral position and a plurality of non-neutral positions. Movement of the switch to a first non-neutral position generates a command to move the propeller blades in a first direction. Movement of the switch to a second non-neutral position generates a command to move the propeller blades in a second direction. Movement of the switch to a third non-neutral position generates a command to move the propeller blades to a zero thrust position.

First claim

What is claimed is:

1. A method of adjusting a pitch of a plurality of propeller blades comprising:
measuring an airspeed and rotor revolutions per minute;
determining in response to the airspeed, rotor revolutions per minute, and at least one discrete logical value, whether to operate a control system for adjusting the pitch of the plurality of propeller blades in a slew mode or a track mode; wherein the at least one discrete logical value is selected from the pitch control system command, an increase/decrease thrust command, latched switch fail, latched loop close switch, and dump valve activated;
issuing a command to one or more actuators coupled to the propeller blades; and
changing the pitch of the one or more propeller blades via the one or more actuators.

2. The method according to claim 1 , wherein in slew mode, the command for the one or more actuators is generated manually via a pitch control system.

3. The method according to claim 2 , wherein the pitch control system includes a switch movable between a neutral position and a plurality of non-neutral position, and the command is generated based on the non-neutral position and a length of time that the switch is held in that non-neutral position.

4. The method according to claim 1 , wherein in track mode, the command for the one or more actuators is generated automatically by a flight control computer.

5. The method according to claim 1 , wherein upon detection of an error, track mode is selected.

Assignees

• Sikorsky Aircraft Corp

Inventors

• Bredenbeck Kevin L
• Cotton Bryan S
• Wilson Mark K

Classifications

• B64C11/34

  automatic · CPC title

• B64C27/82

  characterised by the provision of an auxiliary rotor or fluid-jet device for counter-balancing lifting rotor torque or changing direction of rotorcraft · CPC title

• B64C2027/8236

  including pusher propellers · CPC title

• B64C11/30 Primary

  Blade pitch-changing mechanisms · CPC title

• B64C11/305

  characterised by being influenced by other control systems, e.g. fuel supply · CPC title