Landing gear having tandem wheels and independent shock absorbers

• US 4,681,284 A
• Filed: 05/06/1985
• Issued: 07/21/1987
• Est. Priority Date: 05/15/1984
• Status: Expired due to Fees

• Current Assignee: Messier Hispano Bugatti SA
• Original Assignee: Messier-Hispano-Bugatti
• Inventors: Derrien, Michel, Veaux, Jacques
• Primary Examiner(s): BAREFOOT, GALEN L
• Application Number:
  US06/730,790
• Time in Patent Office: 806 Days
• Field of Search: 244/102 R, 244/102 SS
• US Class Current: 244/102.00R
• CPC Class Codes: B64C 2025/125 into the fuselage, e.g. main landing gear pivotally retracting into or extending out of the fuselage
• CPC Class Codes: B64C 25/14 fore-and-aft
• CPC Class Codes: B64C 25/22 fluid

Abstract

Each rocking arm (9, 10) hinged to a shock absorber (7, 8) has a lateral extension (13, 14) extending at an acute angle a to one side of the shock absorber (7, 8). This extension (13, 14) is connected by a telescopic strut (15, 16) to the opposite end (7A, 8A) of the same shock absorber (7, 8) in order to shorten said shock absorber when the landing gear is raised, thereby reducing the space it occupies in the raised position.

Claims

1. A retractable landing gear having at least two wheels mounted in tandem in a single plane, for an aircraft having a fuselage, said landing gear being retractable into said fuselage in a maximum retraction condition, wherein:

said landing gear comprises a longitudinal beam solidly fixed parallel to said fuselage;

a wheel lever for each said wheel, said wheel lever having top and bottom ends which is hinged by its top end to said beam, respectively to the opposite ends of said beam; and

a rocking arm for each said wheel and having a lower end;

a respective shock absorber for each said wheel hinged at its bottom end to the bottom end of said wheel lever, the opposite end of said shock absorber being hinged to a lower end of said rocking arm which has a pivotal connection with said fuselage at a point on its upper end, both said rocking arms being connected by a parallelogram-shaped hinge constituted by a connecting rod parallel to said fuselage;

an actuator having one end hinged to said fuselage and its other end hinged to either said rocking arm or to said connecting rod; and

each of said rocking arms having a lateral extension near or at its lower end and a telescopic strut articuled with said extension and with said bottom end of said shock absorber to cause said shock absorber to shorten to a maximum retraction condition when said landing gear is retracted by said actuator into said fuselage.

2. A retractable landing gear according to claim 1, wherein said longitudinal beam is solidly fixed parallel to said fuselage by at least one stiffener link means to the same fixing point that said respective rocking arm has a pivotal connection with said fuselage.

3. A retractable landing gear according to claim 1, wherein each said rocking arm and each said shock absorber in the extended position of the landing gear is situated on a broken line having an obtuse angle on one side, on which side said lateral extension is provided to one side of a straight line connecting the hinge between the shock absorber and the wheel lever and the hinge between the rocking arm and the fuselage, and in the retracted position the same rocking arm and the same shock absorber are situated on the other side of the same straight line.

4. A retractable landing gear according to claim 1, wherein each said lateral extension extends, when the landing gear is extended, in a direction which makes an acute angle a with the geometrical direction of the corresponding shock absorber.

5. A retractable landing gear according to claim 4, wherein the actute angle a is chosen to have a value such that in the retracted position of the landing gear each lateral extension extends in a direction which is substantially parallel to the direction of the geometrical axis of the corrsponding shock absorber and in the opposite direction thereto relative to the hinge between said shock absorber and the rocking arm.