Servicing assisting system for shock struts with negative dead volume

Patent metadata

Field	Value
Publication number	US-2017166330-A1
Application number	US-201514969874-A
Country	US
Kind code	A1
Filing date	Dec 15, 2015
Priority date	Dec 15, 2015
Publication date	Jun 15, 2017
Grant date	—

Abstract

System and methods for servicing and monitoring shock struts are provided. A shock strut servicing assistance system may comprise: a controller in electronic communication with a display; and a tangible, non-transitory memory configured to communicate with the controller, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the controller, cause the controller to perform operations comprising: calculating, by the controller, a dead volume of a shock strut and determining, by the controller, a first decision, the first decision being whether or not the dead volume of the shock strut is negative. A shock strut servicing assistance system may be for servicing a shock strut having a negative dead volume.

First claim

What is claimed is:

1 . A shock strut servicing assistance system, comprising:
a controller in electronic communication with a display; and a tangible, non-transitory memory configured to communicate with the controller, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the controller, cause the controller to perform operations comprising: calculating, by the controller, a dead volume of a shock strut; and determining, by the controller, a first decision, the first decision being a Boolean value based upon whether the dead volume of the shock strut is negative.

2 . The shock strut servicing assistance system of claim 1 , wherein the operations further comprise displaying, by the controller, a first prompt on the display, wherein the first prompt is displayed in response to the first decision being true.

3 . The shock strut servicing assistance system of claim 2 , wherein the operations further comprise activating, by the controller, a first shock strut servicing assistance system in response to the first prompt being true.

4 . The shock strut servicing assistance system of claim 2 , wherein the operations further comprise activating, by the controller, a second shock strut servicing assistance system in response to the first prompt being false.

5 . The shock strut servicing assistance system of claim 2 , wherein the first prompt calls for an operator to indicate whether or not a shock strut servicing will be performed under weight-on-wheel conditions.

6 . The shock strut servicing assistance system of claim 1 , wherein the operations further comprise:
receiving, by the controller, a temperature of a gas and at least one shock strut design parameter, wherein the calculating is performed using the temperature of the gas and the at least one shock strut design parameter.

7 . The shock strut servicing assistance system of claim 6 , wherein the at least one shock strut design parameter is received from a memory.

8 . The shock strut servicing assistance system of claim 6 , wherein the temperature of the gas is received from a temperature sensor.

9 . A shock strut servicing assistance system, comprising:
a controller in electronic communication with a display; and a tangible, non-transitory memory configured to communicate with the controller, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the controller, cause the controller to perform operations comprising: sending, by the controller, visible instructions to the display; receiving, by the controller, at least one shock strut parameter; calculating, by the controller, a stroke of a shock strut; comparing, by the controller, the stroke of the shock strut with at least one stroke threshold value; sending, by the controller, an indicator to the display; calculating, by the controller, a volume of an oil located inside of the shock strut; calculating, by the controller, a desired number of moles of a gas; calculating, by the controller, a number of moles of the gas added to the shock strut; and comparing, by the controller, at least one of the desired number of moles of the gas and the number of moles of the gas added to the shock strut with at least one number of moles threshold value.

10 . The shock strut servicing assistance system of claim 9 , wherein the at least one shock strut parameter includes at least one of a gas pressure, a gas temperature, and a shock strut stroke.

11 . The shock strut servicing assistance system of claim 9 , wherein the shock strut servicing assistance system is for servicing a shock strut with a negative dead volume.

12 . The shock strut servicing assistance system of claim 9 , wherein the visible instructions include at least one of:
prompting an operator to add oil to the shock strut via a first valve until oil starts to exit the shock strut via a second valve; prompting the operator to close the second valve; prompting the operator to add oil to the shock strut until the indicator is displayed; prompting the operator to disconnect an oil pump from the shock strut; prompting the operator to add the gas to the shock strut until a pressure inside of the shock strut reaches a pre-determined pressure; or prompting the operator to add the gas to the shock strut until the indicator is displayed.

13 . The shock strut servicing assistance system of claim 9 , wherein the indicator is sent to the display in response to the comparing.

14 . The shock strut servicing assistance system of claim 9 , wherein the shock strut servicing assistance system is for servicing a shock strut of an aircraft under a weight-on-wheel condition.

15 . A method for servicing a shock strut, comprising:
sending, by a controller, visible instructions to a display; receiving, by the controller, at least one shock strut parameter, the at least one shock strut parameter including at least a gas pressure; calculating, by the controller, a stroke of the shock strut; comparing, by the controller, the stroke of the shock strut with at least one stroke threshold value; sending, by the controller, an indicator to the display; comparing, by the controller, the gas pressure with at least one gas pressure threshold value; calculating, by the controller, a volume of an oil located inside of the shock strut; calculating, by the controller, a desired number of moles of a gas; calculating, by the controller, a number of moles of the gas added to the shock strut; and comparing, by the controller, at least one of the desired number of moles of the gas and the number of moles of the gas added to the shock strut with at least one number of moles threshold value.

16 . The method of claim 15 , wherein the at least one shock strut parameter includes at least one of a gas temperature and a shock strut stroke.

17 . The method of claim 15 , wherein the method for servicing the shock strut is for servicing a shock strut with a negative dead volume.

18 . The method of claim 15 , wherein the visible instructions include at least one of:
prompting an operator to compress the shock strut via a landing gear jack until a stroke setpoint is achieved; prompting the operator to add oil to the shock strut via a first valve until oil starts to exit the shock strut via a second valve; prompting the operator to close the second valve; prompting the operator to add oil to the shock strut until the indicator is displayed; prompting the operator to disconnect an oil pump from the shock strut; prompting the operator to lower a landing gear jack; prompting the operator to add the gas to the shock strut until a pressure inside of the shock strut reaches a pre-determined pressure; or prompting the operator to add the gas to the shock strut until the indicator is displayed.

19 . The method of claim 15 , wherein the indicator is sent to the display in response to the comparing.

20 . The method for servicing a shock strut of claim 15 , wherein the method for servicing the shock strut is for servicing a shock strut of an aircraft under a weight-off-wheel condition.

Assignees

• Goodrich Corp

Inventors

• Fazeli Amir
• Cepic Adnan

Classifications

• B64F5/40

  Maintaining or repairing aircraft · CPC title

• B64F5/60

  Testing or inspecting aircraft components or systems · CPC title

• F16F9/3264 Primary

  Arrangements for indicating, e.g. fluid level; Arrangements for checking dampers (F16F9/3292 takes precedence; testing of vehicle damping G01M17/04) · CPC title

• G07C5/006 Primary

  Indicating maintenance · CPC title

• B64C25/60

  Oleo legs · CPC title