Method of fabricating a force transfer part having a lug made of composite material, and a part obtained by such a method

Patent metadata

Field	Value
Publication number	US-2016114884-A1
Application number	US-201514921181-A
Country	US
Kind code	A1
Filing date	Oct 23, 2015
Priority date	Oct 24, 2014
Publication date	Apr 28, 2016
Grant date	—

Abstract

The invention provides a method of fabricating a force transfer part ( 100 ) including at least one lug ( 108 ) made of composite material that is to receive a pin for making a pivot connection with another part, the method comprising making a fiber preform for a main body of the part and making a preform for a reinforcing ring out of discontinuous long fibers, making the reinforcing ring preform to match the dimensions of at least one bore in the preform of the main body, inserting the reinforcing ring preform in the bore of the preform of the main body, and polymerizing the reinforcing ring and main body preforms in injection tooling. The invention also provides a force transfer part obtained by such a method.

First claim

1 . A method of fabricating a force transfer part including at least one lug made of composite material that is to receive a pin for making a pivot connection with another part, the method comprising the following steps:
making a fiber preform for a main body of the part and making a preform for a reinforcing ring out of discontinuous long fibers; making the reinforcing ring preform to match the dimensions of at least one bore in the preform of the main body; inserting the reinforcing ring preform in the bore of the preform of the main body; and polymerizing the reinforcing ring and main body preforms in injection tooling.

2 . A method according to claim 1 , wherein the reinforcing ring preform is made from discontinuous long fibers of carbon or glass that are pre-impregnated with a thermosetting resin.

3 . A method according to claim 2 , wherein the thermosetting resin is selected from at least the following resins: epoxy type resins, cyanate-ester type resins, and polybismaleimide (BMI) resins.

4 . A method according to claim 1 , wherein the reinforcing ring preform is made by winding a mat of discontinuous long fibers around a mandrel.

5 . A method according to claim 1 , wherein the reinforcing ring preform is made by using a “cookie-cutter” punch to cut a ring out from a preform made of discontinuous long fibers.

6 . A method according to claim 1 , wherein the main body preform is made from a fiber blank obtained by: three-dimensional weaving, multilayer weaving of continuous fiber yarns, stacking plies of continuous fibers that are dry or pre-impregnated, shaping discontinuous long fibers that are pre-impregnated.

7 . A method according to claim 1 , wherein the step of polymerizing the reinforcing ring and main body preforms comprises compacting said preforms in injection tooling, the compacting of the reinforcing ring preform being obtained by using an expandable mandrel that is received inside the reinforcing ring preform.

8 . A method according to claim 1 , wherein the bore is cut out in the preform of the main body by using a “cookie-cutter” punch, by ultrasound, by water jet, by laser, or by hand.

9 . A force transfer part including at least one lug of composite material that is to receive a pin for making a pivot connection with another part, the force transfer part comprising:
a main body of composite material made from a fiber preform, said main body being provided with at least one bore; and a reinforcing ring made of composite material that is inserted in the bore in the main body, said reinforcing ring comprising discontinuous long fiber reinforcement densified by a matrix, chips of the reinforcing ring interpenetrating among fibers of the fiber preform of the main body.

10 . A part according to claim 9 , characterized in that it constitutes a lever of an aircraft landing gear side-brace.

Assignees

• Safran

Inventors

• Mandel Robin
• Dunleavy Patrick
• Renaud Mathieu

Classifications

• B29L2031/06

  Rods, e.g. connecting rods {, rails, stakes (shafts B29L2031/75; poles, masts, posts B29L2031/766)} · CPC title

• B29C70/081

  Combinations of fibres of continuous or substantial length and short fibres · CPC title

• F16C9/04

  Connecting-rod bearings; Attachments thereof · CPC title

• F16C2326/43

  Aeroplanes; Helicopters · CPC title

• B29C70/48

  and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] {, e.g. by vacuum} · CPC title