Hydraulic Strut Assembly for Semi-Levered Landing Gear

Abstract

A hydraulic strut assembly, for use in a semi-levered landing gear in an aircraft, comprising an actuator and a manifold associated with the actuator. The actuator comprises a housing, a first piston, a second piston, and a third piston. The first piston is positioned between outer and inner cylindrical structures of the housing. The outer and inner cylindrical structures and first piston form an outer chamber that receives a first fluid. The inner cylindrical structure, the first piston, and the second piston, which is nested within the first piston, form an inner chamber, which holds a second fluid comprising a gas. A volume of the inner chamber changes when at least one of the first and second pistons moves. The third piston is positioned between the outer cylindrical structure and the first piston. The first, second, and third pistons move in a direction parallel to an axis through the housing.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is a continuation-in-part of U.S. patent application Ser. No. 12 / 951,861, filed Nov. 22, 2010, entitled “Hydraulic Actuator for Semi Levered Landing Gear”, which is incorporated herein by reference.BACKGROUND INFORMATION[0002]1. Field[0003]Embodiments of the present disclosure relate generally to landing gear and, more particularly, to a semi-levered landing gear and an associated method of positioning the bogie beam of the landing gear using a telescopic hydraulic actuator.[0004]2. Background[0005]Many airplanes include landing gear to facilitate takeoff, landing and taxi. The landing gear of some aircraft includes a shock absorber that is pivotally attached to a bogie beam at a distal or lower end thereof. The shock absorber may also be referred to as a shock strut. The bogie beam includes two or more axles upon which tires are mounted. In this regard, the bogie beam may include a forward axle positioned forward of the s...

AI Technical Summary

Problems solved by technology

The use of a shrink-link increases the complexity, expense and weight of the resulting semi-levered landing gear more than desired.

Mechanical linkages also may not provide sufficiently desired damping during landing or bogie beam pitch dampening while on the ground.

While a semi-levered landing gear having a locking hydraulic strut is suitable for some aircraft, the landing gear of other aircraft may not have sufficient clearance or room for the hydraulic strut to be positioned between the shock absorber and the bogie beam in an efficient manner.

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