Rudder system for an aircraft

Patent metadata

Field	Value
Publication number	US-2026062119-A1
Application number	US-202418819765-A
Country	US
Kind code	A1
Filing date	Aug 29, 2024
Priority date	Aug 29, 2024
Publication date	Mar 5, 2026
Grant date	—

Abstract

A rudder system of an aircraft includes a first shaft assembly and a second shaft assembly. Each of the first shaft assembly and the second shaft assembly includes a shaft, a trim crank coupled to the shaft, and a pedal crank. The trim crank is configured such that rotation of the trim crank causes rotation of the shaft, and pedal crank is configured such that rotation of the pedal crank causes rotation of the shaft without rotation of the trim crank. The rudder system includes a pedal input link configured to couple the pedal crank of the first shaft assembly and the pedal crank of the second shaft assembly together. The rudder system also includes a rudder trim link configured to couple the trim crank of the first shaft assembly and the trim crank of the second shaft assembly together.

First claim

What is claimed is:

1 . A rudder system of an aircraft to control a position of a rudder, comprising:
a first shaft assembly and a second shaft assembly, wherein each of the first shaft
assembly and the second shaft assembly comprises:
a shaft;
a trim crank coupled to the shaft and configured such that rotation of the trim crank causes rotation of the shaft; and
a pedal crank coupled to the shaft and configured such that rotation of the pedal crank causes rotation of the shaft without rotation of the trim crank;

a pedal input link configured to couple the pedal crank of the first shaft assembly and the pedal crank of the second shaft assembly together; and
a rudder trim link configured to couple the trim crank of the first shaft assembly and the trim crank of the second shaft assembly together.

2 . The rudder system of claim 1 , wherein the rudder trim link comprises a mechanical link between the trim crank of the first shaft assembly and the trim crank of the second shaft assembly.

3 . The rudder system of claim 2 , wherein the mechanical link comprises one or more rods, one or more cable systems, or combinations thereof.

4 . The rudder system of claim 1 , wherein the rudder trim link comprises an electrical and mechanical link.

5 . The rudder system of claim 4 , wherein electrical and mechanical link includes:
wiring that electrically couples a trim actuator of the first shaft assembly to a second drive of the second shaft assembly; and a second control rod that connects the second drive to the trim crank of the second shaft assembly.

6 . The rudder system of claim 5 , wherein each of the trim actuator and the second drive comprise a low gear ratio motor.

7 . The rudder system of claim 1 , wherein each of the first shaft assembly and the second shaft assembly includes a centering unit, and wherein each centering unit includes one or more bias members.

8 . The rudder system of claim 7 , wherein the one or more bias members of the centering unit of the first shaft assembly are configured to cause rotation of the shaft of the first shaft assembly to a first position corresponding to a rudder trim position of the rudder in response to implementation of a change of rudder trim position of the rudder.

9 . The rudder system of claim 7 , wherein the one or more bias members of the first shaft assembly comprise one or more springs, one or more elastic members, or combinations thereof.

10 . The rudder system of claim 7 , wherein:
the one or more bias members are configured to resist rotation of the shaft of the first shaft assembly from a first position corresponding to a rudder trim position of the rudder due to application of a second force to the shaft that rotates the shaft; the first position of the shaft is established by a position of the trim crank of the first shaft assembly; and the one or more bias members are configured to return the shaft toward the first position in response to reduction of the second force.

11 . The rudder system of claim 10 , wherein the second force is configured to be applied to the shaft via the pedal crank due to pilot input to a pedal or via a backdrive crank due to activation of a backdrive actuator.

12 . The rudder system of claim 7 , wherein the centering unit of the first shaft assembly comprises:
a cam coupled to the shaft of the first shaft assembly, wherein the cam includes a travel path for a follower of the trim crank of the first shaft assembly, and wherein the shaft is in a first position corresponding to a rudder trim position of the rudder when the follower is positioned in a detent of the travel path; and the trim crank of the first shaft assembly, wherein the trim crank includes:
a second arm and a third arm; a follower assembly pivotally coupled to the second arm, wherein the follower assembly includes the follower; and
the one or more bias members coupled to the follower assembly and the third arm and configured such that application of a second force to the shaft, via the pedal crank due to pilot input to a pedal or via a back drive crank due to activation of a back drive actuator, causes rotation of the cam, movement of the follower along the travel path, and application by the one or more bias members of a first force to the shaft via the follower and the cam, and wherein the first force resists the second force.

13 . The rudder system of claim 12 , wherein:
the centering unit of the second shaft assembly comprises a second cam; the second cam includes a second travel path with a detent in a middle portion of the second travel path; a trim crank of the second shaft assembly includes a follower positioned on the second travel path; and a shape of the travel path of the cam of the first shaft assembly is different than a shape of the second travel path.

14 . An aircraft comprising:
a first shaft assembly and a second shaft assembly, wherein each of the first shaft assembly and the second shaft assembly comprises:
a shaft; a trim crank coupled to the shaft and configured such that rotation of the trim crank causes rotation of the shaft; and a pedal crank coupled to the shaft and configured such that rotation of the pedal crank causes rotation of the shaft without rotation of the trim crank; a pedal input link configured to couple the pedal crank of the first shaft assembly and the pedal crank of the second shaft assembly together; a rudder trim link configured to couple the trim crank of the first shaft assembly and the trim crank of the second shaft assembly together; and a control system configured to receive first signals from one or more sensors of the first shaft assembly, receive second signals from one or more sensors of the second shaft assembly, and cause a rudder command signal to be sent to one or more rudder actuators to adjust a position of a rudder of the aircraft based on the first signals and the second signals.

15 . The aircraft of claim 14 , wherein the rudder trim link comprises a mechanical link between the trim crank of the first shaft assembly and the trim crank of the second shaft assembly.

16 . The aircraft of claim 14 , wherein the rudder trim link comprises an electrical and mechanical link.

17 . The aircraft of claim 14 , wherein each of the first shaft assembly and the second shaft assembly includes a centering unit.

18 . A method for rudder control of an aircraft comprising:
receiving input, at a control system, to change rudder trim of the aircraft to a particular rudder trim position; and sending a rudder trim command signal from the control system to a trim actuator of a first shaft assembly, wherein the rudder trim command signal causes the trim actuator to rotate a trim crank of the first shaft assembly, wherein a rudder trim link causes corresponding rotation of a trim crank of a second shaft assembly, wherein each of the first shaft assembly and the second shaft assembly comprise: a shaft; the trim crank coupled to the shaft and configured such that rotation of the trim crank causes rotation of the shaft; and a pedal crank coupled to the shaft and configured such that rotation of the pedal crank causes rotation of the shaft without rotation of the trim crank; and wherein the pedal crank of the first shaft assembly and the pedal crank of the second shaft assembly are coupled together by a pedal input link.

19 . The method of claim 18 , wherein the rudder trim link comprises a mechanical link between the trim crank of the first shaft assembly and the trim c

Assignees

• Boeing Co

Inventors

• Whittington Seth Alan
• Elliott Joseph E

Classifications

• B64C13/044 Primary

  operated by feet, e.g. pedals · CPC title