Attachment of Ignition Suppression or Quenching Device to a Fastener Stack

Patent metadata

Field	Value
Publication number	US-2022220995-A1
Application number	US-202117466088-A
Country	US
Kind code	A1
Filing date	Sep 3, 2021
Priority date	Jan 13, 2021
Publication date	Jul 14, 2022
Grant date	—

Abstract

A device which is attachable to a fastener stack, the device comprising: an attachment element made of shape memory material; and a cap comprising a base having an aperture and a shell having an interior space in fluid communication with the opening, wherein the base supports the shell and is coupled to the attachment element.

First claim

1 . A device which is attachable to a fastener stack, the device comprising:
an attachment element made of shape memory material which is configured to clamp onto a portion of the fastener stack when the shape memory material is stimulated into a state of compression; and a cap comprising a base having an opening and a shell having an interior space in fluid communication with the opening, wherein the base is coupled to the attachment element.

2 . The device as recited in claim 1 , wherein the attachment element comprises a ring.

3 . The device as recited in claim 2 , wherein the base of the cap comprises a plurality of slots and the attachment element further comprises a plurality of tabs which are respectively seated in the plurality of slots.

4 . The device as recited in claim 2 , wherein the base of the cap comprises internal threads and the attachment element further comprises external threads which are interengaged with the internal threads of the base of the cap.

5 . The device as recited in claim 1 , further comprising a base seal.

6 . The device as recited in claim 5 , wherein the base of the cap further comprises a groove in which the base seal is seated.

7 . The device as recited in claim 1 , wherein the cap is made of porous material.

8 . The device as recited in claim 1 , wherein the attachment element in a pre-stimulus state is U-shaped and in a post-stimulus state is circular or arc-shaped.

9 . A device comprising:
an attachment element comprising a first ring made of shape memory material having an aperture and an inner circumferential seat; and a base seal comprising a second ring made of thermoplastic material which is seated on and has a knife edge lip pointing away from the inner circumferential seat of the attachment element.

10 . The device as recited in claim 9 , wherein the first ring is configured to transform from a first state in which the first ring is not clamped onto a portion of a fastener stack to a second state in which the first ring is clamped onto the portion of the fastener stack in response to a stimulus.

11 . The device as recited in claim 9 , further comprising a cap which is impermeable to fluids, integrally formed with the base seal, and attached to the attachment element.

12 . An assembly comprising:
first and second plates which are mutually adjacent and have respective holes which are mutually aligned; a fastener stack comprising a fastener and a mating part, a portion of the fastener being disposed in the aligned holes; an attachment element made of shape memory material in a state of compression whereby the attachment element is clamped onto a portion of the fastener stack; and a cap comprising a base having an aperture and a shell having an interior space in fluid communication with the opening, wherein the base is in contact with the first plate, is coupled to the attachment element, and supports the shell in a position such that the interior space of the shell is partially occupied by the portion of the fastener stack.

13 . The assembly as recited in claim 12 , wherein the portion of the fastener stack onto which the attachment element is clamped is selected from a group consisting of a washer, a nut, a collar, a bolt head, and external projections of a mating portion of a fastener.

14 . The assembly as recited in claim 12 , further comprising a base seal, wherein the base of the cap further comprises a groove in which the base seal is seated.

15 . The assembly as recited in claim 14 , wherein the cap is configured to contain fluids.

16 . The assembly as recited in claim 12 , wherein the cap comprises a porous portion.

17 . An assembly comprising:
a plate having a hole; a fastener stack comprising a fastener and a mating part; an attachment element comprising a ring made of shape memory material in a state of compression whereby the attachment element is clamped onto a portion of the fastener stack; and a base seal made of thermoplastic material which surrounds a portion of the fastener stack and is disposed between the attachment element and the plate.

18 . The assembly as recited in claim 17 , further comprising a cap which is impermeable to fluids, integrally formed with the base seal, and attached to the attachment element.

19 . A method for covering a portion of a fastener stack, the method comprising:
(a) placing an attachment element made of shape memory material having a first shape so that the attachment element is adjacent to the fastener stack along at least a portion of a periphery of the fastener stack; (b) applying a stimulus to the shape memory material that is sufficient to cause the shape memory material in place to transform to a second shape in which the attachment element is compressively attached to the fastener stack; and (c) attaching a cap to the attachment element, the cap having an interior space that is sized to receive a portion of the fastener stack.

20 . The method as recited in claim 19 , wherein step (c) is performed prior to step (a).

21 . The method as recited in claim 19 , wherein step (c) is performed subsequent to step (b).

22 . The method as recited in claim 21 , wherein step (c) comprises twist-locking the cap onto the attachment element.

23 . The method as recited in claim 21 , wherein step (c) comprises threadably coupling the cap to the attachment element.

Assignees

• Boeing Co

Inventors

• Roper Christopher S
• O'Masta Mark R
• Dessalegn Haftom Y

Classifications

• B64D45/02

  Lightning protectors; Static dischargers · CPC title

• F16B37/14 Primary

  Cap nuts; Nut caps or bolt caps · CPC title

• B64D37/32

  Safety measures not otherwise provided for, e.g. preventing explosive conditions · CPC title

• F16B33/004

  Sealing; Insulation (by means of washers F16B43/001) · CPC title

• F16B2200/77

  Use of a shape-memory material · CPC title