Pre-Weakening Of Fabric Covered Airbag Doors

• US 20070040360A1
• Filed: 08/18/2006
• Published: 02/22/2007
• Est. Priority Date: 02/24/2003
• Status: Active Grant

• Current Assignee: Collins & Aikman Automotive Company Incorporated
• Original Assignee: Collins & Aikman Holdings SA de CV
• Inventors: RIHA, Keith, WEISSERT, Ulrich, GRAY, John, SULLIVAN, A. Hardy, BATCHELDER, Bruce, TOTTEN, Brian
• Granted Patent: US 7,556,284 B2
• Time in Patent Office: Days
• US Class Current: 280/728.300
• CPC Class Codes: B23K 2103/172 wherein at least one of the layers is non-metallic
• CPC Class Codes: B23K 2103/38 Fabrics, fibrous materials
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: B29C 2035/0827 using UV radiation
• CPC Class Codes: B29C 2035/0838 using laser
• CPC Class Codes: B29C 37/0032 the coating being applied upon the mould surface before introducing the moulding compound, e.g. applying a gelcoat B29C44/14 and B29C44/32 take precedence
• CPC Class Codes: B29C 59/007 Forming single grooves or ribs, e.g. tear lines, weak spots by moulding B29C37/0057; folding lines B29C53/06; in metal articles B21D17/00; by cutting B26D3/08
• CPC Class Codes: B29C 59/16 by wave energy or particle radiation , e.g. infrared heating B29C59/007 takes precedence
• CPC Class Codes: B29L 2009/00 Layered products
• CPC Class Codes: B29L 2031/3005 Body finishings
• CPC Class Codes: B32B 2262/02 Synthetic macromolecular fibres
• CPC Class Codes: B32B 2605/003 Interior finishings
• CPC Class Codes: B32B 3/10 characterised by a discontinuous layer, i.e. formed of separate pieces of material
• CPC Class Codes: B32B 3/266 characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
• CPC Class Codes: B32B 43/003 Cutting
• CPC Class Codes: B32B 5/026 Knitted fabric
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B60R 21/2165 characterised by a tear line for defining a deployment opening
• CPC Class Codes: D03D 1/02 Inflatable articles
• CPC Class Codes: D03D 15/573 : Tensile strength
• CPC Class Codes: D03D 27/00 : Woven pile fabrics
• CPC Class Codes: D04B 19/00 : Unravelling knitted fabrics
• CPC Class Codes: D06M 11/38 : Oxides or hydroxides of elements of Groups 1 or 11 of the Periodic Table
• CPC Class Codes: D06M 23/16 : Processes for the non-uniform application of treating agents, e.g. one-sided treatment; Differential treatment
• CPC Class Codes: D06Q 1/02 : Producing patterns by locally destroying or modifying the fibres of a web by chemical actions, e.g. making translucent
• CPC Class Codes: D10B 2201/02 : Cotton
• CPC Class Codes: D10B 2201/04 : Linen
• CPC Class Codes: D10B 2201/06 : Jute
• CPC Class Codes: D10B 2201/20 : Cellulose-derived artificial fibres
• CPC Class Codes: D10B 2201/24 : Viscose
• CPC Class Codes: D10B 2201/28 : Cellulose esters or ethers, e.g. cellulose acetate
• CPC Class Codes: D10B 2211/02 : Wool
• CPC Class Codes: D10B 2321/021 : polyethylene
• CPC Class Codes: D10B 2321/022 : polypropylene
• CPC Class Codes: D10B 2321/06 : polymers of unsaturated alcohols, e.g. polyvinyl alcohol, or of their acetals or ketals
• CPC Class Codes: D10B 2321/10 : polymers of unsaturated nitriles, e.g. polyacrylonitrile, polyvinylidene cyanide
• CPC Class Codes: D10B 2331/02 : polyamides D10B2331/08 takes precedence
• CPC Class Codes: D10B 2331/021 : aromatic polyamides, e.g. aramides
• CPC Class Codes: D10B 2331/04 : polyesters, e.g. polyethylene terephthalate [PET]
• CPC Class Codes: D10B 2401/041 : thermoplastic; thermosetting
• CPC Class Codes: D10B 2401/063 : high strength
• CPC Class Codes: D10B 2505/124 : Air bags

Abstract

A variety of embodiments are disclosed, in both apparatus and method form, that relate to the use of fabric material in the manufacture of an air bag deployment system. In addition, fabric weakening is disclosed according to a technique that does not result in physical alteration of the fabric. This invention therefore includes an air bag cover for an air bag safety system for a vehicle comprising a fabric outer layer having a frontside and a backside and a substrate containing an opening wherein the opening has a periphery. The substrate is preferably formed by low pressure molding, wherein the fabric outer layer overlies the opening in the substrate, and wherein the fabric outer layer is weakened at a location that is adjacent or overlies the substrate opening periphery.

Claims

1. An air bag cover for an air bag safety system for a vehicle comprising:

a fabric outer layer having a front side and a backside,

a substrate containing an opening, said opening closed by an airbag door, said door having a periphery at least a portion of which comprises a door/substrate tear seam, the substrate formed by low pressure molding at a clamp pressure of less than or equal to about 1000 psi.,

wherein the fabric outer layer overlies the opening in the substrate, and wherein the fabric outer layer is weakened at a location a portion of which is located outboard of said door/substrate tear seam.

2. The air bag cover of claim 1, wherein said door is formed integrally with said substrate, said door having an outer edge.

3. The air bag cover of claim 1, wherein the fabric outer layer includes a backing layer positioned between said fabric outer layer and said substrate.

4. The air bag cover of claim 1, wherein said fabric outer layer is weakened by partially cutting into the backside of said fabric outer layer.

5. The air bag cover of claim 3 wherein said weakening of said fabric outer layer including said backing layer is provided by cutting with a laser or knife.

6. The air bag cover of claim 3, wherein at least one of said fabric outer layer, said backing layer or said substrate are weakened by the application of a knife or a laser and at least partially cutting through any one of said fabric outer layer, said backing layer or said substrate.

7. The air bag cover of claim 4 wherein the fabric outer layer is weakened in a pattern that lies just outside of the opening in the substrate that is closed by the door.

8. The air bag cover of claim 1 wherein said low pressure molding comprises one of sequential injection molding, reaction injection molding, injection-compression molding, gas assist injection molding, structural foam molding, gas counter-pressure injection molding, and extrusion molding.

9. A method for forming a trim panel for concealing an air bag system, said trim panel having a molded substrate, said substrate having first and second opposing surfaces and a fabric applied to said first surface, the method comprising the steps of:

(a) providing a mold assembly having coacting first and second mold members, the first mold member having a cavity portion disposed thereon and the second mold member having a detail portion disposed thereon, said first and second mold members being interchangeable with each other such that the cavity and core portions cooperatively define an interior cavity of said mold assembly;

said cavity portion having a series of blade members extending therefrom to substantially engage with said core portion when said mold assembly is closed, said blade members disposed in a pattern that at least partially outlines the periphery of said door;

(b) providing a sheet of fabric for application to said trim panel;

(c) placing the fabric sheet between said coacting first and second mold members in alignment with said cavity portion;

(d) engaging said first and second mold members together to form said mold assembly interior cavity;

(e) injecting a plastic material into said interior mold cavity to integrally form said injection molded substrate and said door and urging the sheet of fabric into contact with the surface of the cavity portion including the blade portions extending from the cavity portion; and

(f) removing said trim panel from said mold assembly; and

weakening said fabric in the slots formed by said thin blade members.

10. The method of claim 9 wherein said fabric is weakened by a cut via projecting a knife or laser through said slots formed in said trim panel wherein said cut is either partially through or completely through said fabric.

11. The method of claim 9 further wherein said step of providing a sheet of fabric includes providing a sheet of fabric containing a backing layer.

12. The method of claim 11 wherein said weakening of said fabric includes weakening of said backing layer.

13. The method of claim 12 wherein said weakening of said backing layer comprises cutting either partially or completely through said backing layer.

14. A method for forming a trim panel for concealing an air bag system, said trim panel having a low pressure injection molded substrate, said substrate having first and second opposing surfaces and a fabric applied to said first surface, the method comprising the steps of:

(a) providing a mold assembly having contacting first and second mold members, the first mold member having a cavity portion disposed thereon and the second mold member having a detail portion disposed thereon, said first and second mold members being interchangeable with each other such that the cavity and core portions cooperatively define an interior cavity of said mold assembly;

(b) providing a sheet of fabric for application to said trim panel;

(c) placing the fabric sheet between said contacting first and second mold members in alignment with said cavity portion;

(d) engaging said first and second mold members together to form said mold assembly interior cavity;

(e) injecting a plastic material into said interior mold cavity to integrally form said low pressure injection molded substrate and said door and urging the sheet of fabric into contact with the surface of the cavity portion; and

(f) removing said trim panel from said mold assembly; and

weakening any one of said fabric sheet or said substrate.

15. The air bag cover of claim 14, wherein at least one of said fabric outer layer or said substrate are weakened in by the application of a knife or a laser and at least partially cutting through any one of said fabric outer layer or said substrate.

16. The trim panel of claim 14 further including wherein the fabric sheet includes a backing layer.

17. The trim panel of claim 16, wherein at least one of said fabric sheet, said backing layer or said substrate are weakened in by the application of a knife or a laser and at least partially cutting through any one of said fabric outer layer, said backing layer or said substrate.

18. The trim panel of claim 14 wherein said low pressure molded substrate is formed by one of sequential injection molding, reaction injection molding, injection-compression molding, gas assist injection molding, structural foam molding, gas counter-pressure injection molding, and extrusion molding.