Fibre flattening

Patent metadata

Field	Value
Publication number	US-11673299-B2
Application number	US-201917042701-A
Country	US
Kind code	B2
Filing date	Mar 26, 2019
Priority date	Mar 29, 2018
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

A method of forming a fibre article, comprising: providing a former having a contoured forming surface; locating a fibre preform between a first diaphragm and a second diaphragm, the second diaphragm being offset from the forming surface; drawing a vacuum between the first and second diaphragms so as to hold the preform captive between the diaphragms; displacing the second diaphragm towards the former so as to bring the second diaphragm into partial contact with the former; drawing a vacuum between the second diaphragm and the former so as to bring at least a part of the second diaphragm adjoining the preform into conformity with the forming surface; and setting the preform in its configuration; wherein: the fibre preform comprises one or more substantially inextensible fibres extending linearly in a first direction; the forming surface comprises a concavity and prominences on either side of the concavity; and the step of bringing the second diaphragm into partial contact with the former comprises bringing the second diaphragm into contact with the prominences whilst the second diaphragm does not fully contact the concavity and with the substantially inextensible fibres extending from one of the prominences to the other.

First claim

The invention claimed is:

1. A method of forming a fibre article, comprising:
providing a former having a contoured forming surface;
locating a fibre preform between a first diaphragm and a second diaphragm, the second diaphragm being offset from the forming surface;
drawing a vacuum between the first and second diaphragms so as to hold the preform captive between the diaphragms;
displacing the second diaphragm towards the former so as to bring the second diaphragm into partial contact with the former;
drawing a vacuum between the second diaphragm and the former so as to bring at least a part of the second diaphragm adjoining the preform into conformity with the forming surface; and
setting the preform in its configuration;

wherein:
the fibre preform comprises one or more substantially inextensible fibres extending linearly in a first direction, and a first sheet of fibre material, the fibres of the first sheet being offset from the first direction by at least 30°, the said substantially inextensible fibres being laminated to the first sheet, and the said substantially inextensible fibres extend in the first direction beyond the boundary of the first sheet;
the forming surface comprises a concavity and prominences on either side of the concavity; and
the step of bringing the second diaphragm into partial contact with the former comprises bringing the second diaphragm into contact with the prominences whilst the second diaphragm does not fully contact the concavity and with the substantially inextensible fibres extending from one of the prominences to the other.

2. A method as claimed in claim 1 , wherein the fibre preform comprises a second sheet of fibre material, the fibres of the second sheet being offset from the first direction by at least 30° and the said substantially inextensible fibres being laminated to the second sheet and being located between the first sheet and the second sheet.

3. A method as claimed in claim 2 , wherein the said substantially inextensible fibres extend in the first direction beyond the boundary of the second sheet.

4. A method as claimed in claim 3 , wherein the said inextensible fibres are comprised in a sheet of fibre material.

5. A method as claimed in claim 2 , wherein the diaphragms are elastic.

6. A method as claimed in claim 5 , wherein the step of bringing the second diaphragm into partial contact with the former comprises, after bringing the second diaphragm into contact with the prominences whilst the second diaphragm does not fully contact the concavity, stretching the diaphragm over the prominences so as to cause the substantially inextensible fibres to apply tension to a portion of the preform extending across the concavity.

7. A method as claimed in claim 2 , wherein the said inextensible fibres are comprised in a sheet of fibre material.

8. A method as claimed in claim 1 , wherein the said inextensible fibres are comprised in a sheet of fibre material.

9. A method as claimed in claim 1 , wherein the or each sheet of fibre material is a sheet of woven fibre material.

10. A method as claimed in claim 1 , wherein the diaphragms are elastic.

11. A method as claimed in claim 10 , wherein the step of bringing the second diaphragm into partial contact with the former comprises, after bringing the second diaphragm into contact with the prominences whilst the second diaphragm does not fully contact the concavity, stretching the diaphragm over the prominences so as to cause the substantially inextensible fibres to apply tension to a portion of the preform extending across the concavity.

Assignees

• Mclaren Automotive Ltd

Inventors

• Santoni Claudio

Classifications

• B29C2043/3655

  Pressure transmitters, e.g. caul plates; pressure pads · CPC title

• B29C70/56 Primary

  Tensioning reinforcements before or during shaping · CPC title

• B29C43/3642 Primary

  Bags, bleeder sheets or cauls for isostatic pressing · CPC title

• B29C51/28

  for applying pressure through the wall of an inflated bag or diaphragm · CPC title

• B29C2791/006

  Using vacuum · CPC title