Spark containment cap

Patent metadata

Field	Value
Publication number	US-9951804-B2
Application number	US-201514964475-A
Country	US
Kind code	B2
Filing date	Dec 9, 2015
Priority date	Dec 16, 2014
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A spark containment cap is disclosed for enclosing an end of a fastener protruding from a structure. The cap includes a cap body having an annular base terminating at a rim which surrounds an opening into an air cavity arranged to enclose the fastener end and having an aperture in fluid communication with the cavity. An annular bead of uncured sealing material is provided around the opening into the cavity, the bead of sealing material being curable to provide a seal between the cap body and the structure to seal a volume of gas within the cavity. A closure member has a closed configuration in which it seals the aperture, and an open configuration in which it does not seal the aperture.

First claim

The invention claimed is:

1. A spark containment cap for enclosing an end of a fastener protruding from a structure, the cap comprising:
a cap body having an annular base terminating at a rim which surrounds an opening into an air cavity arranged to enclose the fastener end and having an aperture in fluid communication with the cavity;
an annular bead of uncured sealing material around the opening into the cavity, the bead of sealing material being curable to provide a seal between the cap body and the structure to seal a volume of gas within the cavity; and
a closure member having a closed configuration in which it seals the aperture, and an open configuration in which it does not seal the aperture.

2. A cap according to claim 1 , wherein the closure member comprises a curable sealing material arranged to cure in the closed configuration.

3. A cap according to claim 1 , wherein the closure member comprises a fastener passing through the aperture in the closed configuration.

4. A cap according to claim 1 , wherein the closure member comprises a lid arranged to interlock with the cap body in the closed configuration.

5. A cap according to claim 4 , wherein the lid and the cap body each comprise cooperating interlocking features arranged to interlock the lid with the cap body in the closed configuration.

6. A cap according to claim 1 , wherein the cap comprises an annular skirt extending from the cap body to provide an annular sealing volume between the skirt and the annular base for containing the annular bead of sealing material.

7. A cap according to claim 6 , wherein the cap comprises a sealant inlet hole in fluid communication with the annular sealing volume and arranged to interconnect with a sealing material injection device to provide a flow of sealing material into the annular sealing volume via the sealant inlet hole.

8. A cap according to claim 7 , wherein the sealant inlet hole extends through the annular skirt.

9. A cap according to claim 6 , wherein the cap body comprises an inner cap member and the annular skirt comprises a base of an outer cap member which fits over the inner cap member, and wherein the aperture extends through the inner cap member and the outer cap member.

10. A joint comprising:
a structure;
a fastener having a fastener end protruding from the structure; and
a spark containment cap according to claim 1 , the cap body of the spark containment cap being arranged over the fastener end so that the fastener end is enclosed within the cavity, the cap closure member being arranged in the closed configuration to seal the aperture, and the bead of sealing material being arranged between the cap body and the structure to thereby seal a volume of gas within the air cavity.

11. A joint according to claim 10 , wherein the structure comprises a boundary of an aircraft fuel tank.

12. A method of installing a spark containment cap over an end of a fastener protruding from a structure, the cap including a cap body having a cavity, the method including the steps of:
assembling the cap body with the fastener end so that the fastener end is enclosed within the cavity, the cap body having an aperture that is in fluid communication with the cavity;
providing an annular bead of uncured sealing material between the structure and the cap;
curing the bead of sealing material; and
sealing the aperture to thereby seal a volume of gas within the cavity after the bead of sealing material is substantially or partially cured.

13. A method according to claim 12 , wherein the method includes forming the aperture in the cap body after the step of assembling the cap body with the fastener end.

Assignees

• Airbus Operations Ltd

Inventors

• Dobbin Richard
• Humphrys Ben

Classifications

• B64D45/02

  Lightning protectors; Static dischargers · CPC title

• F16B33/004

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

• F16B37/14 Primary

  Cap nuts; Nut caps or bolt caps · CPC title