Landing gear storage and quick servicing solution

Patent metadata

Field	Value
Publication number	US-11479347-B2
Application number	US-201715608544-A
Country	US
Kind code	B2
Filing date	May 30, 2017
Priority date	Jun 1, 2016
Publication date	Oct 25, 2022
Grant date	Oct 25, 2022

Abstract

A method for pressurizing and depressurizing a shock absorber of an aircraft. More specifically, it relates to a method in which an aircraft weight and ambient temperature are used to calculate a required pressurization level of a shock absorber. As such, the shock absorber may be pressurized to the correct level without applying an iterative approach, greatly reducing initialization time.

First claim

The invention claimed is:

1. A method of pressurising or depressurising an aircraft shock absorber, comprising:
determining the weight of the aircraft;
measuring an ambient temperature around the shock absorber;
calculating a target length of the shock absorber based on the ambient temperature and the determined weight of the aircraft; and
pressurising or depressurising the shock absorber to the target length;
wherein the step of determining the weight of the aircraft comprises increasing the internal pressure of the shock absorber from a fully compressed length of the shock absorber until the shock absorber begins to extend in length and then measuring the internal pressure of the shock absorber when the shock absorber begins to extend.

2. A method according to claim 1 , wherein the target length is a shock absorber maintenance length, a flight length or a storage length.

3. A method according to claim 1 , wherein the length of the shock absorber is measured using a Rotary Variable Differential Transducer.

4. A method according to claim 1 , wherein the shock absorber is pressurised using Nitrogen gas.

5. A method according to claim 1 , wherein the method is performed on at least two shock absorbers simultaneously.

6. The method according to claim 1 , wherein increasing the internal pressure comprises increasing the internal pressure from a state where the shock absorber length is not determined by the internal pressure.

7. The method according to claim 1 , wherein increasing the internal pressure comprises increasing the internal pressure from a shortest shock absorber length where the length of the shock absorber is determined by the internal pressure.

8. A system for pressurising or depressurising a shock absorber of an aircraft, comprising:
pressurisation means, in fluid connection with the shock absorber;
a temperature sensor, arranged to measure an ambient temperature around the system; and
control logic, arranged to control the pressurisation means,
wherein the control logic comprises a processor arranged to:
determine the weight of the aircraft;
receive an ambient temperature measurement from the temperature sensor;
calculate a target shock absorber length based on the temperature measurement and the determined weight of the aircraft; and
instruct the pressurisation means to pressurise or depressurise the shock absorber to the target length;
wherein the processor is configured to determine the weight of the aircraft by:
instructing the pressurisation means to increase the internal pressure of the shock absorber from a fully compressed length of the shock absorber until the shock absorber begins to extend in length; and
measuring the internal pressure of the shock absorber when the shock absorber begins to extend.

9. The system according to claim 8 , wherein increasing the internal pressure comprises increasing the internal pressure from a state where the shock absorber length is not determined by the internal pressure.

10. The system according to claim 8 , wherein measuring the internal pressure comprises measuring the internal pressure at a shortest shock absorber length where the length of the shock absorber is determined by the internal pressure.

Assignees

• Safran Landing Systems Uk Ltd

Inventors

• Simonneaux Yann
• Smith Jon

Classifications

• B64C25/60 Primary

  Oleo legs · CPC title

• B64F5/60

  Testing or inspecting aircraft components or systems · CPC title

• G05B19/04

  Program control other than numerical control, i.e. in sequence controllers or logic controllers (G05B19/418 takes precedence) · CPC title

• F16F9/0245

  Means for adjusting the length of, or for locking, the spring or dampers · CPC title

• B64C25/62 Primary

  Spring shock-absorbers; Springs · CPC title