Method of Repairing a Core Stiffened Structure

Patent metadata

Field	Value
Publication number	US-2016101878-A1
Application number	US-201414512837-A
Country	US
Kind code	A1
Filing date	Oct 13, 2014
Priority date	Oct 13, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

A method of repairing a core stiffened structure, including removing a damaged portion of the core stiffened structure; bonding a shelf onto a first core member; bonding a second core member to a shelf; and securing a skin patch over the second core member.

First claim

1 . A method of repairing a core stiffened structure, the method comprising:
removing a damaged portion of the core stiffened structure; bonding a shelf onto a first core member; bonding a second core member to the shelf; and securing a skin patch over the second core member.

2 . The method according to claim 1 , wherein the step of removing the damaged portion includes removing a skin portion and a damaged core portion.

3 . The method according to claim 1 , wherein the step of bonding the shelf onto the first core member includes locating an adhesive approximate to a lower surface of the shelf and an upper surface network of the first core member.

4 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf includes depositing a foam mixture into a cell of the second core member.

5 . The method according to claim 4 , further comprising:
allowing the foam mixture to expand and fill the plurality of cells so as to form an expanded foam; and trimming the expanded foam.

6 . The method according to claim 1 , further comprising:
curing the skin patch.

7 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf also includes depositing a foam mixture into a space between outer cell members of the second core member and adjacent cells walls of the first core member.

8 . The method according to claim 1 , wherein the core stiffened structure is a rotor blade.

9 . The method according to claim 1 , wherein the skin patch is a composite member.

10 . The method according to claim 1 , wherein the shelf is a composite member.

11 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf also includes applying a foam adhesive into a space between outer cell members of the second core member and adjacent cells walls of the first core member.

12 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf also includes applying a past adhesive into between outer cell members of the second core member and adjacent cells walls of the first core member.

13 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf includes applying a film adhesive between the second core member and an upper surface of the shelf.

14 . The method according to claim 1 , wherein the step of bonding the second core member to the shelf includes applying a foam adhesive between the second core member and an upper surface of the shelf.

15 . A repaired core stiffened structure, comprising:
a lower skin; an upper skin; a core member; a cavity formed from a partial removal of the upper skin and the core member; a shelf bonded within the cavity; a repair core member bonded on the shelf within the cavity; and a skin patch.

16 . The repaired core stiffened structure according to claim 15 , wherein the core member includes a plurality of cells.

17 . The repaired core stiffened structure according to claim 15 , wherein the core member has hexagonal shaped cells.

18 . The repaired core stiffened structure according to claim 15 , wherein the core stiffened structure is an airfoil member.

19 . The repaired core stiffened structure according to claim 15 , wherein the core stiffened structure is a rotor blade.

20 . The repaired core stiffened structure according to claim 15 , wherein the shelf is a composite member.

Assignees

• Bell Helicopter Textron Inc

Inventors

• Wardlaw Robert
• Modrzejewski Brian S
• Mueller Byron
• Cribb Iii Vance N

Classifications

• B29C2073/264

  for cutting out or grooving the area to be repaired · CPC title

• B29C44/1285

  the preformed part being foamed · CPC title

• B29L2031/082

  Blades, e.g. for helicopters · CPC title

• B32B2038/0076

  Curing, vulcanising, cross-linking · CPC title

• B64F5/40

  Maintaining or repairing aircraft · CPC title