Leak-proof fastening device

Patent metadata

Field	Value
Publication number	US-9574603-B2
Application number	US-201314073116-A
Country	US
Kind code	B2
Filing date	Nov 6, 2013
Priority date	Nov 12, 2012
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

The present invention pertains to a washer ( 11 ) for a female fastener ( 12, 12 A), particularly a nut or collar, said washer comprising an annular base ( 15 ) and a substantially cylindrical skirt ( 13 ) of an outer periphery of the annular base, said annular base comprising a central orifice ( 18 ) coaxial with the axis ( 14 ) of the skirt, characterized in that the annular base is at least partially covered with a layer ( 21 ) of a viscous composition capable of forming a liquid-tight coating through polymerization.
When installing a nut having such a washer onto a male fastener such as a pin ( 33 ), the spreading of the viscous layer makes it possible to fill in the gaps ( 36 ) of the assembly, the polymerization of the composition ensuring its leak-tightness afterwards.

First claim

The invention claimed is:

1. An assembly comprising a washer and a female fastener onto which the washer is assembled, said washer comprising an annular base and a substantially cylindrical skirt rigidly connected to an outer periphery of the annular base, the annular base being at least partially covered with a layer of a viscous composition capable of forming a liquid-tight seal through polymerization, characterized in that the female fastener is assembled onto the washer and the female fastener and the washer are adhered together by the layer of the viscous composition in an uncured state before joining with a mating fastener and while allowing rotation between the female fastener and the washer.

2. An assembly according to claim 1 , such that the female fastener is a nut or a collar.

3. An assembly according to claim 1 , such that the skirt of the washer has an elastic skirt portion for joining with the female fastener, said elastic skirt portion allowing the female fastener to rotate with respect to the washer.

4. An assembly according to claim 1 , such that the viscous composition comprises a liquid polysulfide and a reagent capable of releasing oxygen.

5. An assembly according to claim 4 , such that the reagent capable of releasing oxygen is manganese dioxide.

6. An assembly according to claim 5 , such that the liquid polysulfide and/or reagent capable of releasing oxygen are in microencapsulated form in the viscous composition.

7. An assembly according to claim 5 , such that the liquid polysulfide and/or reagent capable of releasing oxygen are in mixed form in the viscous composition.

8. An assembly according to claim 4 , such that the liquid polysulfide and/or reagent capable of releasing oxygen are in microencapsulated form in the viscous composition.

9. An assembly according to claim 4 , such that the liquid polysulfide and/or reagent capable of releasing oxygen are in mixed form in the viscous composition.

10. An assembly according to claim 1 , such that the annular base is flat or truncated-cone-shaped.

11. An assembly according to claim 1 , such that the annular base forms an angle greater than or equal to 90° with the skirt.

12. A leak-proof assembly method of a fastening system, said system comprising:
an assembly including a washer and a female fastener onto which the washer is assembled, said washer comprising an annular base and a substantially cylindrical skirt rigidly connected to an outer periphery of the annular base, the annular base being at least partially covered with a layer of a viscous composition capable of forming a liquid-tight seal through polymerization, wherein the female fastener is assembled onto the washer by adhering to the layer of the viscous composition before assembly onto a male fastener,
said assembly comprising the female fastener being free to rotate with respect to the washer, the layer of viscous composition being located between a proximal plane of the female fastener and an annular base of the washer,
a male fastener having an end capable of cooperating with the female fastener, said method comprising the following steps:
inserting the male fastener into a bore of structural elements to be fastened;
installing the assembly onto the end of the male fastener, to the point that the washer is brought in contact with one of the structural elements to be fastened, in order to lock the axial rotation of said washer relative to said structural element;
installing the female fastener onto the male fastener, its movement relative to the washer causing the viscous composition layer to spread towards the axis of the annular base in order to fill in the gaps formed between the male fastener, the female fastener, and the bore;
after full installation of the female fastener, hardening the viscous composition through polymerization, so as to make the system and the structural elements leak-proof.

13. A method according to claim 12 , such that:
the annular base of the washer supporting the layer of a viscous composition is truncated-cone-shaped;
installing the female fastener causes said annular base to compress between a structural element and the flat proximal face of the female fastener, said compression causing said annular base of the washer to flatten.

14. A method according to claim 12 , wherein the male fastener is a pin, a lockbolt, a pin with a sleeve, or a lockbolt with a sleeve.

15. A leak-proof assembly method of a fastening system, said system comprising:
an assembly including a washer and a female fastener onto which the washer is assembled, said washer including an annular base and a substantially cylindrical skirt rigidly connected to an outer periphery of the annular base, the annular base being at least partially covered with a layer of a viscous composition capable of forming a liquid-tight seal through polymerization, wherein the viscous composition includes a liquid polysulfide and a reagent capable of releasing oxygen, wherein the liquid polysulfide and/or reagent capable of releasing oxygen are in microencapsulated form in the viscous composition, wherein the female fastener is assembled onto the washer by adhering to the layer of the viscous composition before assembly onto a male fastener,
wherein the female fastener is free to rotate with respect to the washer, the layer of viscous composition being located between a proximal plane of the female fastener and an annular base of the washer,
a male fastener having an end capable of cooperating with the female fastener, said method comprising the following steps:
inserting the male fastener into a bore of structural elements to be fastened;
installing the assembly onto the end of the male fastener, to the point that the washer is brought in contact with one of the structural elements to be fastened, in order to lock the axial rotation of said washer relative to said structural element;
installing the female fastener onto the male fastener, the movement of said female fastener relative to the washer causing the viscous composition layer to spread towards the axis of the annular base in order to fill in the gaps formed between the male fastener, the female fastener, and the bore;
said movement of the female fastener relative to the washer also causing the microcapsules to break and the liquid polysulfide and reagent capable of releasing oxygen to mix with the viscous composition;
after full installation of the female fastener, hardening the viscous composition through polymerization, so as to make the system and the structural elements leak-proof.

Assignees

• Lisi Aerospace

Inventors

• Verdier Florent
• Regnard Benoit

Classifications

• F16B11/004 Primary

  by cold pressure welding · CPC title

• F16B39/225

  by means of a settable material · CPC title

• B29C65/562

  using extra joining elements, i.e. which are not integral with the parts to be joined (using plastic snap elements B29C65/58; using plastic rivets B29C65/601) · CPC title

• F16B19/05

  Bolts fastening by swaged-on collars (F16B19/08 takes precedence) · CPC title

• B29C65/561

  using screw-threads being integral at least to one of the parts to be joined · CPC title