Bistable control valve for maintaining fluid pressure in a parking brake system

Patent metadata

Field	Value
Publication number	US-11059473-B2
Application number	US-201916535948-A
Country	US
Kind code	B2
Filing date	Aug 8, 2019
Priority date	Aug 8, 2019
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

A parking brake system is disclosed and includes a parking brake valve configured to maintain a fluid pressure of the parking brake system and one or more pressure transducers that monitor the fluid pressure of the parking brake system. The parking brake system also includes a bistable control valve fluidly connected to the parking brake valve, one or more processors in electronic communication with the bistable control valve, the parking brake valve, and the one or more pressure transducers, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the parking brake system to instruct the bistable control valve to actuate into the opened position when the fluid pressure of the parking brake system is less than a threshold pressure.

First claim

What is claimed is:

1. A parking brake system including a parking brake valve configured to maintain a fluid pressure of the parking brake system and one or more pressure transducers that monitor the fluid pressure of the parking brake system, the parking brake system comprising:
a bistable control valve fluidly connected to the parking brake valve, wherein the bistable control valve is configured to actuate between an opened position and a closed position, and wherein the bistable control valve is configured to retain a last switching state even after an input signal is no longer available;
one or more processors in electronic communication with the bistable control valve, the parking brake valve, and the one or more pressure transducers; and
a memory coupled to the one or more processors, the memory storing data comprising a database and program code that, when executed by the one or more processors, causes the parking brake system to:
receive a plurality of brake signals indicating a user is engaging the parking brake system;
in response to receiving the plurality of brake signals, monitor the one or more pressure transducers to determine the fluid pressure of the parking brake system;
determine the fluid pressure of the parking brake system is less than a threshold pressure; and
in response to determining the fluid pressure of the parking brake system is less than the threshold pressure, instruct the bistable control valve to actuate into the opened position.

2. The parking brake system of claim 1 , further comprising a return pressure conduit fluidly connected to the parking brake valve.

3. The parking brake system of claim 2 , wherein the bistable control valve is fluidly connected to the return pressure conduit of the parking brake system when placed in the closed position.

4. The parking brake system of claim 1 , further comprising a supply pressure conduit fluidly connected to the bistable control valve.

5. The parking brake system of claim 4 , further comprising a brake line conduit, wherein the bistable control valve fluidly connects the brake line conduit with the supply pressure conduit when in the opened position.

6. The parking brake system of claim 1 , wherein the one or more processors execute instructions to:
in response to receiving the plurality of brake signals, instruct the parking brake valve to close and block off a return pressure conduit of the parking brake system.

7. The parking brake system of claim 1 , wherein the bistable control valve is a mechanically operated hydraulic control valve.

8. The parking brake system of claim 1 , further comprising a force member positioned within a cylinder, wherein the parking brake valve is fluidly connected to the cylinder.

9. The parking brake system of claim 8 , wherein the threshold pressure indicates the fluid pressure at the parking brake is sufficient to keep the force member in place for a predetermined amount of time.

10. The parking brake system of claim 1 , further comprising a plurality of brake pedals in communication with the one or more processors, wherein the plurality of brake pedals are configured to generate a depression signal in response to being depressed.

11. The parking brake system of claim 10 , further comprising a brake selection device, wherein the brake selection device is configured to generate a set signal in response to being placed in an engaged state.

12. The parking brake system of claim 11 , wherein the plurality of braking signals include the set signal generated by the brake selection device and the depression signal generated by the plurality of brake pedals.

13. A method of operating a parking brake system, wherein the parking brake system includes a parking brake valve and a bistable control valve fluidly connected to the parking brake valve, wherein the method includes:
receiving, by a computer, a plurality of brake signals indicating the parking brake system is being placed into an engaged state;
in response to receiving the plurality of brake signals, monitoring one or more pressure transducers to determine fluid pressure of the parking brake system, wherein the one or more pressure transducers monitor the fluid pressure of the parking brake system;
determining the fluid pressure of the parking brake system is less than a threshold pressure; and
in response to determining the fluid pressure of the parking brake system is less than the threshold pressure, instruct the bistable control valve to actuate from a closed position into an opened position, wherein the bistable control valve is configured to retain a last switching state even after an input signal is no longer available.

14. The method of claim 13 , further comprising:
in response to receiving the plurality of brake signals, instructing the parking brake valve to close and block off a return pressure conduit of the parking brake system.

15. The method of claim 13 , further comprising:
determining, by the computer, the fluid pressure of the parking brake system is equal to or greater than the threshold pressure; and
in response to determining the fluid pressure of the parking brake system is equal to or greater than the threshold pressure, continuing to instruct the bistable control valve to remain in the closed position.

16. An aircraft having a parking brake system, wherein the aircraft comprises:
a parking brake valve configured to maintain hydraulic pressure of the parking brake system;
one or more pressure transducers that monitor the hydraulic pressure of the parking brake system;
a bistable control valve fluidly connected to the parking brake valve, wherein the bistable control valve is configured to actuate between an opened position and a closed position, and wherein the bistable control valve is configured to retain a last switching state even after an input signal is no longer available;
one or more processors in electronic communication with the bistable control valve, the parking brake valve, and the one or more pressure transducers; and
a memory coupled to the one or more processors, the memory storing data comprising a database and program code that, when executed by the one or more processors, causes the parking brake system to:
receive a plurality of brake signals indicating a user is engaging the parking brake system;
in response to receiving the plurality of brake signals, monitor the one or more pressure transducers to determine the hydraulic pressure of the parking brake system;
determine the hydraulic pressure of the parking brake system is less than a threshold pressure; and
in response to determining the hydraulic pressure of the parking brake system is less than the threshold pressure, instruct the bistable control valve to actuate into the opened position.

17. The aircraft of claim 16 , further comprising a return pressure conduit fluidly connected to the parking brake valve, wherein the bistable control valve is fluidly connected to the return pressure conduit of the parking brake system when placed in the closed position.

18. The aircraft of claim 16 , wherein the one or more processors execute instructions to:
in response to receiving the plurality of brake signals, instruct the parking brake valve to close and block off a return pressure conduit of the parking brake system.

19. The aircraft of claim 16 , wherein the bistable control valve is a mechanically operated hydraulic control valve.

20. The aircraft of claim 16 , further comprising a force member positioned within a cylinder, wherein the

Assignees

• Boeing Co

Inventors

• Smith Steven Elliot
• Yamamoto David T
• Forghani Nima

Classifications

• B60W10/182 Primary

  including control of parking brakes · CPC title

• F16H63/486

  Common control of parking locks or brakes in the transmission and other parking brakes, e.g. wheel brakes · CPC title

• B60T15/025

  Electrically controlled valves · CPC title

• F16H59/54

  dependent on signals from the brakes, e.g. parking brakes · CPC title

• B64C25/44

  Actuating mechanisms · CPC title