Method for determining a recommended inflation pressure for an aircraft tire, and associated maintenance methods

Patent metadata

Field	Value
Publication number	US-11655053-B2
Application number	US-201816759539-A
Country	US
Kind code	B2
Filing date	Oct 26, 2018
Priority date	Oct 27, 2017
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

A method determines an inflation pressure expected in an aircraft tire provided with a pressure and temperature sensor. Also disclosed is a method for assistance in the maintenance for an aircraft tire and also a portable electronic device intended for assistance in the maintenance.

First claim

The invention claimed is:

1. A method for determining an inflation pressure expected in an aircraft tire provided with a pressure and temperature sensor, the method comprising:
in a preliminary stage, recording a pressure P 0 and a temperature T 0 of the tire, measured at a time t 0 , in a memory of the pressure and temperature sensor;
at a moment t, measuring and comparing an internal air temperature T m of the tire and an ambient air temperature T amb ; and
if the two temperatures are equal or substantially equal, determining a pressure expected at the moment t, P expected_hom , using P expected_hom =P 0 *T m /T 0 ; or
if the two temperatures are different, determining a pressure expected at the moment t, P expected_het , using P expected_het =F(T m , P 0 , T 0 and θ), where θ depends on a position of the pressure and temperature sensor in the tire at the moment t,
wherein F is a linear function where P expected_het (t)=A(θ)*(T m (t)−T 0 )+P 0 , A(θ)=p 1 *θ+p 2 , and p 1 and p 2 are predetermined constants, or F is a polynomial function where P expected_het =A(θ)*(T m (t)−T 0 ) 2 +B(θ)*(T m −T 0 )+P 0 and A(θ) and B(θ) are predetermined polynomial functions.

2. A method for the detection of loss of pressure in an aircraft tire provided with a pressure and temperature sensor, the method comprising:
determining an expected pressure P exp of the tire using the method according to claim 1 ;
measuring an internal air pressure P m of the tire at the moment t is measured; and
comparing values P exp and P m such that if P exp =P m , then no loss of pressure is detected, and if P exp >P m , a rate of loss of pressure V p is determined, where, if V p is less than a predetermined threshold, an acceptable loss of pressure is detected, and, if V p is greater than the predetermined threshold, an unacceptable loss of pressure is detected.

3. The method according to claim 2 , wherein the predetermined threshold is expressed as percentage and is between 4 and 10% per 24 h.

4. The method according to claim 2 , wherein a rate of loss of pressure is calculated as follows: V p =(P 0 −P 0,eq )/P c *(t−t 0 ), where P 0,eq is a pressure which would be necessary to have at the moment to in order for the pressure expected at the moment t to be equal to P m .

5. A method for assistance in maintenance for an aircraft tire provided with a pressure and temperature sensor, comprising:
determining an expected pressure P exp of the tire using the method according to claim 1 ;
determining a takeoff pressure P tak in the absence of maintenance;
calculating a ratio of the takeoff pressure P tak to a set pressure P s and, depending on a value of the ratio, carrying out a maintenance operation.

6. The method according to claim 5 , wherein the takeoff pressure P tak in the absence of maintenance is determined as follows:
calculating a temperature of the tire at takeoff T tak ; and
calculating P tak =P 0 *T tak /T 0 .

7. The method according to claim 5 , wherein the maintenance operation, knowing a set pressure P s of the tire, is selected from the group consisting of:
doing nothing if the P tak /P s ratio is between 100% and 105%,
inflating the tire if the ratio is between 95% and 100%,
deflating the tire if the ratio is greater than 105%, and
inspecting a fitted assembly if the ratio is less than 95%.

Assignees

• Michelin & Cie
• Safran
• Safran Landing Systems
• Safran Electronics & Defense

Inventors

• Arnoux Michael
• Neba Eric Carin

Classifications

• B64D2045/0085

  Devices for aircraft health monitoring, e.g. monitoring flutter or vibration · CPC title

• B64F5/60 Primary

  Testing or inspecting aircraft components or systems · CPC title

• B60C23/0479

  Communicating with external units being not part of the vehicle, e.g. tools for diagnostic, mobile phones, electronic keys or service stations · CPC title

• B60C23/20 Primary

  Devices for measuring or signalling tyre temperature {only} · CPC title

• B64F5/40

  Maintaining or repairing aircraft · CPC title