Retractable aircraft landing gear

Patent metadata

Field	Value
Publication number	US-12097950-B2
Application number	US-202217735606-A
Country	US
Kind code	B2
Filing date	May 3, 2022
Priority date	May 4, 2021
Publication date	Sep 24, 2024
Grant date	Sep 24, 2024

Abstract

An aircraft landing gear is disclosed including a main leg, a foldable stay and a lock link configured to hold the foldable stay in position when the landing gear is extended. The foldable stay includes a first stay member and a second stay member, and the landing gear is configured such that the second stay member rotates in a first direction from a first position to a second position as the landing gear moves from a retracted configuration to an extended configuration. An end stop is arranged such that in the event the lock link fails, the second stay member rotates in the first direction from the second position to a third position in which the stay contacts the end stop thereby preventing further movement of the second stay member in the first direction and wherein the foldable stay goes over centre as the second stay member moves from the first position to the third position.

First claim

The invention claimed is:

1. An aircraft landing gear assembly, comprising:
a main leg;
a foldable stay comprising a first stay member and a second stay member, the first stay member being pivotally connected to the second stay member, the second stay member being pivotally mounted on the main leg, the landing gear assembly is configured such that the second stay member rotates in a first direction from a first position to a second position relative to the main leg as the landing gear assembly moves from a retracted configuration to an extended configuration;
a lock link configured to prevent rotation of the second stay member away from the second position in the first direction when the lock link is in a locked position; and,
an end stop arranged such that in the event the lock link fails, the second stay member rotates in the first direction from the second position to a third position in which the foldable stay contacts the end stop thereby preventing further movement of the second stay member in the first direction and wherein the foldable stay goes over centre as the second stay member moves from the first position to the third position.

2. An aircraft landing gear assembly according to claim 1 , wherein
the second stay member is pivotally connected at a first pivot point to the main leg and at a second pivot point to the first stay member;
the first stay member is pivotally connected at a first pivot point to the second stay member and configured for pivotal connection at a second pivot point;
each of the first and second stay members has a longitudinal axis being a notional straight line between the first and second pivot points;
a first angle is defined as an angle between the longitudinal axis of the first stay member and the longitudinal axis of the second stay member; and,
the landing gear is configured such that the first angle increases as the landing gear assembly moves from the retracted configuration to the extended configuration, and the first angle is greater than 180 degrees when the stay is in contact with the end stop.

3. An aircraft landing gear assembly according to claim 1 , wherein the end stop is arranged to contact the second stay member such that further movement of the second stay member in the first direction is prevented.

4. An aircraft landing gear assembly according to claim 3 , wherein the end stop is mounted on the main leg.

5. An aircraft landing gear assembly according to claim 1 , wherein the end stop is arranged to contact the first stay member such that further movement of the second stay member in the first direction is prevented.

6. An aircraft landing gear assembly according to claim 5 , wherein the second end of the first stay member is pivotally connected to the aircraft structure and the end stop is mounted on the aircraft structure in the region of the second end of the stay.

7. An aircraft landing gear assembly according to claim 1 , wherein the end stop is mounted on one of the first and second stay member, to contact the other of the first and second stay member such that further movement of the second stay member in the first direction is prevented.

8. An aircraft landing gear assembly according to claim 1 , wherein the second stay member is pivotally connected at a first end to the main leg and at a second end to the first stay member, and the first stay member is pivotally connected at a first end to the second stay member and configured for pivotal connection at a second end to the rest of the aircraft.

9. An aircraft landing gear assembly according to claim 1 , wherein the foldable stay is a drag stay.

10. An aircraft landing gear assembly according to claim 1 , wherein the foldable stay is a side-stay.

11. An aircraft landing gear assembly according to claim 1 , wherein a first end of the lock link is pivotally mounted on the stay and a second end of the lock link is pivotally mounted on the main leg.

12. An aircraft landing gear assembly according to claim 11 , wherein the second end of the lock link is pivotally mounted to a main fitting of the main leg.

13. An aircraft landing gear assembly according to claim 1 , wherein the landing gear is a nose landing gear assembly.

14. An aircraft including an aircraft landing gear assembly according to claim 1 .

15. A method of operating a landing gear, the landing gear comprising a main leg, a foldable stay comprising first and second stay members, a lock link, and an end stop, and the first stay member is pivotally connected at a first pivot point to the second stay member and configured for pivotal connection at a second pivot point and the second stay member is pivotally connected at a first pivot point to the main leg and at a second pivot point to the first stay member; each of the first and second stay members has a longitudinal axis being a notional straight line between the first and second pivot points and a first angle is defined as an angle between the longitudinal axis of the first stay member and the longitudinal axis of the second stay member; and wherein:
during normal operation the stay folds as the landing gear retracts, such that the first angle between the first stay member and the second stay members reduces; the stay unfolds as the landing gear extends, such that the first angle between the first stay member and the second stay members increases; and the lock link holds the stay in a first position when the landing gear is extended; and
in the event the lock link fails, the stay continues to unfold until it contacts the end stop which prevents further unfolding, and the first angle is greater than 180 degrees when the stay is in contact with the end stop.

16. An aircraft landing gear assembly, comprising:
a main leg;
a foldable stay comprising a first stay member and a second stay member, the first stay member is pivotally connected at a first pivot point to the second stay member and configured for pivotal connection to the rest of the aircraft at a second pivot point and the second stay member is pivotally connected at a first pivot point to the main leg and at a second pivot point to the first stay member;
each of the first and second stay members has a longitudinal axis being a notional straight line between the first and second pivot points and a first angle is defined as an angle between the longitudinal axis of the first stay member and the longitudinal axis of the second stay member; and wherein
the landing gear assembly is configured such that the first angle increases as the landing gear assembly moves from a retracted configuration to an extended configuration, the first angle being less than 180 degrees when the landing gear is in the retracted configuration;

a lock link configured to lock the foldable stay in position when the landing gear is in the extended configuration; and,
an end stop arranged to limit the increase in the first angle in the event the lock link fails by limiting movement of the foldable stay, and wherein the first angle is greater than 180 degrees when the foldable stay is in contact with the end stop.

Assignees

• Airbus Operations Ltd
• Airbus Operations Sas
• Airbus Operations Sas

Inventors

• Venn Robert
• Mounty Andy
• Marples Matthew
• Tizac Laurent

Classifications

• B64C25/30

  emergency actuated · CPC title

• B64C25/26 Primary

  Control or locking systems therefor · CPC title