Servicing procedure for single-stage mixed fluid/gas shock strut

Patent metadata

Field	Value
Publication number	US-10018240-B2
Application number	US-201514934741-A
Country	US
Kind code	B2
Filing date	Nov 6, 2015
Priority date	Nov 6, 2015
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

Methods for servicing shock struts are provided. In various embodiments, a method for servicing a shock strut may comprise deflating the shock strut; compressing the shock strut until the shock strut is in a fully compressed position; and charging the shock strut with a liquid until a pressure of the liquid decreases a volume of a residual air located inside of the shock strut. In various embodiments, charging the shock strut with liquid under pressure may reduce the volume of trapped air inside of the shock strut to a negligible volume, eliminating the servicing variations.

First claim

What is claimed is:

1. A method for servicing a shock strut comprising:
deflating the shock strut;
compressing the shock strut until the shock strut is in a fully compressed position; and
charging the shock strut with a liquid until a pressure of the liquid decreases a volume of a residual air located inside of the shock strut while the shock strut remains in the fully compressed position; and
with the shock strut in the fully compressed position, increasing the pressure of the liquid until the shock strut reaches a pre-determined extension, wherein the pressure is increased by moving additional liquid into the shock strut.

2. The method of claim 1 , further comprising charging the shock strut with a gas.

3. The method of claim 1 , wherein the shock strut includes a first valve and a second valve.

4. The method of claim 1 , wherein the compressing is performed via at least one of a jack or a weight of a vehicle, the vehicle supported at least in part by the shock strut.

5. The method of claim 4 , further comprising lowering the jack until a shock strut piston is in a fully extended position.

6. The method of claim 1 , wherein the pre-determined extension is determined, at least in part, based upon a servicing temperature.

7. A method for weight on wheel shock strut servicing comprising:
deflating the shock strut until the shock strut is in a fully compressed position;
charging the shock strut with an oil until a pressure of the oil decreases a volume of a residual air located inside of the shock strut, wherein the charging the shock strut with the oil comprises pumping the oil into a second valve and closing a first valve in response to the oil exiting the shock strut via the first valve; and
charging the shock strut with a gas until the gas comprises a pre-determined pressure.

8. The method of claim 7 , wherein the deflating comprises releasing the gas from the shock strut, wherein a weight of a vehicle, supported at least in part by the shock strut, compresses the shock strut.

9. The method of claim 7 , wherein the pre-determined pressure is determined, at least in part, based upon a servicing temperature.

10. The method of claim 7 , further comprising increasing the pressure of the oil until a shock strut piston reaches a pre-determined extension.

11. The method of claim 10 , wherein the pre-determined extension is determined, at least in part, based upon a servicing temperature.

Assignees

• Goodrich Corp

Inventors

• Fazeli Amir
• Cepic Adnan
• Reber Susanne

Classifications

• B64C25/60

  Oleo legs · CPC title

• B64F5/0081

  Operations & Transport · mapped topic

• F16F9/3271 Primary

  Assembly or repair · CPC title

• F16F2230/46

  Maintenance · CPC title

• F16F9/06

  using both gas and liquid {(F16F9/486 take precedence; self-pumping fluid springs B60G17/044)} · CPC title