Pressure activated latch

• US 20070202759A1
• Filed: 02/24/2006
• Published: 08/30/2007
• Est. Priority Date: 02/24/2006
• Status: Active Grant

• Current Assignee: Apical Industries, Inc. (Transdigm Group Incorporated)
• Original Assignee: Apical Industries, Inc. (Transdigm Group Incorporated)
• Inventors: Bermal, Jay
• Granted Patent: US 7,329,164 B2
• Time in Patent Office: Days
• US Class Current: 441/42
• CPC Class Codes: B64C 1/1415 Cargo doors, e.g. incorporating ramps
• CPC Class Codes: E05B 47/0038 using permanent magnets
• CPC Class Codes: E05B 51/02 by pneumatic or hydraulic means E05B17/0029 takes precedence
• CPC Class Codes: Y10T 292/0969 Spring projected
• CPC Class Codes: Y10T 292/097 Operating means
• CPC Class Codes: Y10T 292/1021 Motor

Abstract

A pressure activated latch includes a latch housing, a fluid inlet, a fluid outlet, an internal biasing member and a sliding latch pin that is configured to engage a latch tab that is substantially adjacent to the latch housing. The latch pin is slidable between a first position in which the latch pin prevents fluid communication between the fluid inlet and the fluid outlet and engages the latch tab and a second position in which the latch pin is disengaged from the latch tab and fluid communication is permitted between the fluid inlet and the fluid outlet. The internal biasing member is configured to apply a force upon the latch pin to bias it into the first position.

Claims

1. A pressure activated latch, comprising:

a latch housing;

a latch pin slidably coupled to the latch housing between a first extended position and a second retracted position;

a fluid inlet port;

a fluid outlet port; and

an internal biasing element configured to force the latch pin to the first position,

wherein the latch pin prevents fluid communication between the fluid inlet port and the fluid outlet port in the first position, and

wherein there is fluid communication between the fluid inlet port and the fluid outlet port when the latch pin is in the second position.

2. The pressure activated latch of claim 1, wherein the internal biasing element is a spring.

3. The pressure activated latch of claim 1, wherein the latch pin includes an interface portion configured to engage a latch tab that is substantially adjacent to the latch housing when the latch pin is in the first position.

4. The pressure activated latch of claim 3, wherein the interface portion is configured to be disengaged from the latch tab when the latch pin is in the second position.

5. The pressure activated latch of claim 3, wherein the interface portion is configured to disengage from the latch tab when the latch pin is between the first and the second position.

6. The pressure activated latch of claim 1, wherein the latch housing includes a longitudinal bore and a portion of the latch pin is disposed in the longitudinal bore.

7. The pressure activated latch of claim 6, wherein the fluid inlet port is in fluid communication with the longitudinal bore substantially adjacent to a first end of the longitudinal bore and the fluid outlet port is in fluid communication with the longitudinal bore substantially adjacent to a second end of the longitudinal bore.

8. The pressure activated latch of claim 1, further comprising at least one sealing member configured to create a fluid seal between the latch pin and the latch housing.

9. The pressure activated latch of claim 8, wherein the sealing member is an o-ring.

10. A pressure activated latch for latching an emergency door of an aircraft emergency flotation system, comprising:

a latch housing including a fluid inlet and a fluid outlet spaced longitudinally from the fluid inlet;

a latch pin including an interface portion that extends out of the latch housing in a latched position and a sealing portion, the latch pin being configured to slide within the latch housing between the latched position and an unlatched position in which the interface portion is retracted into the latch housing; and

an internal biasing element disposed within the latch housing and configured to bias the latch pin to the latched position,

wherein the interface portion of the latch pin is engaged with a latch tab of the emergency door and the sealing portion of the latch pin is configured to prevent fluid communication between the fluid inlet and the fluid outlet when the latch pin is in the latched position, and

wherein the interface portion of the latch pin is disengaged from the latch tab of the emergency door and the sealing portion of the latch pin is configured to allow fluid communication between the fluid inlet and the fluid outlet when the latch pin is in the unlatched position.

11. The pressure activated latch of claim 10, wherein the internal biasing element is a helical spring.

12. The pressure activated latch of claim 10, wherein the internal biasing element is a plurality of belville spring washers.

13. The pressure activated latch of claim 10, wherein latch pin is configured to slide away from the latch tab when moving from the latched position to the unlatched position.

14. The pressure activated latch of claim 13, wherein outlet is located further proximal from the latch tab than the fluid inlet.

15. The pressure activated latch of claim 10, wherein latch pin includes a travel limit stop that is configured to limit the travel of latch pin so that the sealing portion is spaced from the fluid inlet when latch pin is in the latched position.

16. An emergency flotation system, comprising

a pressurized fluid source;

an inflatable device storage compartment including a lid and lid latching tabs;

a plurality of pressure activated latches including configured to selectively engage the lid latching tabs, wherein each pressure activated latch includes a fluid inlet, a fluid outlet, a latch pin that is slidable between a first extended position and a second retracted position, and an internal biasing element configured to bias latch pin to the first position wherein in the first position the latch pin prevents fluid communication between the inlet and the outlet, and wherein the pressure activated latches are fluidly coupled to each other; and

an inflatable device coupled in fluid communication with the pressurized fluid source through the plurality of pressure activated latches.

17. The emergency flotation system of claim 16, wherein the plurality of pressure activated latches are fluidly coupled to each other in series.

18. The emergency flotation system of claim 16, wherein the plurality of pressure activated latches are fluidly coupled to each other in parallel.

19. The emergency flotation system of claim 16, further comprising a pressure valve interposed between the pressurized fluid source and the plurality of pressure activated latches.

20. The emergency flotation system of claim 19, wherein the pressure valve is configured to be operated remotely.