Blended fiber mat formation for structural applications

Patent metadata

Field	Value
Publication number	US-11072092-B2
Application number	US-201716465467-A
Country	US
Kind code	B2
Filing date	Nov 29, 2017
Priority date	Nov 30, 2016
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A process and system are provided for introducing a blend of chopped and dispersed fibers on an automated production line amenable for inclusion in molding compositions as a blended fiber mat for structural applications. The blend of fibers are simultaneously supplied to an automated cutting machine illustratively including a rotary blade chopper disposed above a vortex supporting chamber. The blend of chopped fibers and binder form a chopped mat. The chopped mat has a veil mat placed on either side, and is consolidated with the veil mat using heated rollers maintained at the softening temperature of thermoplastic binder, with consolidated mats being amenable to being stored in rolls or as flat sheets. A charge pattern is made using the consolidated mat, and the charge pattern can be compression molded in a mold maintained at a temperature lower than the melting point of the thermoplastic fibers.

First claim

The invention claimed is:

1. A process of forming a mat containing a blended fiber filler comprising:
providing two or more different types of fiber tow;
feeding the two or more different types of fiber tow simultaneously to an automated cutting machine to produce chopped fibers;
passing the chopped fibers through a vortex chamber into which a pressurized gas flow having both rotary and vertical flow components forming a vortex is directed to debundle the chopped fibers to form the blended fiber filler;
coating the chopped and debundled fibers that form the blended fiber filler with a binder and other additives; and
moving the coated fibers of the blended fiber filler to a treatment chamber to form a blended fiber mat having the binder therein.

2. The process of claim 1 wherein said two or more different types of fiber tow comprises at least two tows, each of the at least two tows comprising fibers selected from the group consisting of: glass fiber, carbon fiber, polyimide fiber, polyaramide fiber, polyester fiber, polyamide fiber, and binder fiber.

3. The process of claim 1 wherein said automated cutting machine is a rotating chopper vertically disposed above said vortex chamber.

4. The process of claim 1 wherein said two or more different types of fiber tow are supplied to provide a defined ratio by weight in the blended fiber mat.

5. The process of claim 1 further comprising exposing the chopped fibers to a plasma treatment.

6. The process of claim 5 wherein said vortex chamber includes a plasma generation electrode set that provides plasma exposure to the chopped fibers within said vortex chamber.

7. The process of claim 5 further comprising placing a veiled mat on a side of the blended fiber mat.

8. The process of claim 7 wherein the veiled mat is formed of glass fiber, carbon fiber, thermoplastic fiber, or a combination thereof.

9. The process of claim 7 further comprising consolidating the blended fiber mat with the veiled mat to form a consolidated mat using a set of heated rollers, wherein the veiled mat has a binder therein, the binders in the blended fiber mat and the veiled mat each comprise a thermoplastic binder having a softening temperature, and the heated rollers are maintained at the softening temperature of the thermoplastic binders in both the veiled mat and the blended fiber mat.

10. The process of claim 1 wherein said binder is in the form of a powder, a fiber, or a solvent spray.

11. The process of claim 1 wherein said vortex chamber is a tube having a uniform vertical cross-section.

Assignees

• Continental Structural Plastics Inc
• Continental Structural Plastics

Inventors

• Guha Probir Kumar
• Bonte Philippe
• Toitgans Marc-Philippe
• Boyer Dominique
• Boivin Gaetan
• Harbonner Anais

Classifications

• D04H1/58

  by applying, incorporating or activating chemical or thermoplastic bonding agents, e.g. adhesives (in combination with needling D04H1/488) · CPC title

• B29C70/12

  using fibres of short length, e.g. in the form of a mat {(non-woven fabrics per se D04H1/00)} · CPC title

• B29C70/506

  and impregnating by melting a solid material, e.g. sheet, powder, fibres (B29C70/508 takes precedence) · CPC title

• D06M10/025

  Corona discharge or low temperature plasma · CPC title

• B32B5/26

  another layer {next to it} also being fibrous or filamentary {(relative arrangement of fibres or filaments of different layers B32B5/12)} · CPC title