Aircraft undercarriage fitted with a device for detecting bottoming of its shock absorber

Patent metadata

Field	Value
Publication number	US-11142336-B2
Application number	US-202016856908-A
Country	US
Kind code	B2
Filing date	Apr 23, 2020
Priority date	Apr 25, 2019
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

An aircraft undercarriage comprising a shock absorber further comprising first and second portions that are mounted to slide telescopically relative to each other and that can come into internal abutment in the event of the shock absorber being compressed, the undercarriage being fitted with a detector device for detecting the shock absorber coming into internal abutment, which comprises firstly a punch secured to the first portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the first portion of the shock absorber, and secondly a sacrificial piece secured to the second portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the second portion of the shock absorber, the punch and the sacrificial piece being arranged in such a manner that, in the event of the two portions of the shock absorber coming into internal abutment, the punch strikes the sacrificial piece so as to form an indentation therein.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An aircraft undercarriage comprising
a shock absorber comprising first and second portions that are mounted to slide telescopically relative to each other and that can come into internal abutment in the event of the shock absorber being compressed, the undercarriage being fitted with a detector fitted to the undercarriage, the detector configured to detect the shock absorber coming into internal abutment, said detector comprising firstly a punch secured to the first portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the first portion of the shock absorber, and secondly a sacrificial piece secured to the second portion of the shock absorber or to a portion of the undercarriage that does not slide relative to the second portion of the shock absorber, the punch and the sacrificial piece being arranged in such a manner that, in the event of the two portions of the shock absorber coming into internal abutment, the punch strikes the sacrificial piece so as to form an indentation therein.

2. The aircraft undercarriage according to claim 1 , wherein the punch is a pyramid-shaped point.

3. The aircraft undercarriage according to claim 2 , wherein the pyramid-shaped point is secured to a plate fitted to the undercarriage with interposed peelable shims.

4. The aircraft undercarriage according to claim 1 , wherein the sacrificial piece is a pellet.

5. The aircraft undercarriage according to claim 4 , wherein the pellet is carried by a tray formed integrally with the sliding rod of the undercarriage.

6. The aircraft undercarriage according to claim 1 , wherein the undercarriage is of the direct type in which the first portion of the shock absorber is formed by a strut of the undercarriage and the second portion of the shock absorber is formed by a sliding rod carrying at least one axle and mounted to slide telescopically in the strut, and wherein the punch is carried by the strut and the sacrificial piece is carried by the sliding rod.

7. The aircraft undercarriage according to claim 1 , wherein the undercarriage is of the type having a rocker lever hinged to a strut, the shock absorber being coupled to the rocker lever and to the strut and comprising a cylinder in which a rod is mounted to slide telescopically, the punch and the sacrificial piece being secured, one to the cylinder and the other to the rod.

8. The aircraft undercarriage according to claim 1 , wherein the undercarriage is of the steerable type comprising a steering tube mounted to turn relative to a strut of the undercarriage and connected by a scissors leakage to a rod carrying an axle and slidably mounted in the strut, the rod forming a cylinder of the shock absorber of the undercarriage, the punch and the sacrificial piece being secured, one to the rod and the other to the steering tube.

Assignees

• Safran Landing Systems

Inventors

• Farcy Marc
• Faure Thibault
• Renault Frédéric

Classifications

• B64D2045/008

  Devices for detecting or indicating hard landing · CPC title

• B64C25/60 Primary

  Oleo legs · CPC title

• B64F5/60 Primary

  Testing or inspecting aircraft components or systems · CPC title

• B64C25/50

  Steerable undercarriages; Shimmy-damping · CPC title

• B64D45/00

  Aircraft indicators or protectors not otherwise provided for · CPC title