Low permeation fittings, low permeation containers utilizing same, and methods for forming same

• US 20020063129A1
• Filed: 11/09/2001
• Published: 05/30/2002
• Est. Priority Date: 11/30/2000
• Status: Active Grant

• Current Assignee: Hanon Systems (Hahn & Co. Auto Holdings Co. Ltd.)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Vorenkamp, Erich James, Potter, James Fuller, Fish, Duane Allen, Thorn, John E., Vaughn, Link E.
• Granted Patent: US 6,860,398 B2
• Time in Patent Office: Days
• US Class Current: 220/4.13
• CPC Class Codes: B29C 2049/7862 characterised by temperature values or ranges
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 2791/006 Using vacuum
• CPC Class Codes: B29C 49/04 Extrusion blow-moulding
• CPC Class Codes: B29C 49/0691 using sheet like material, e.g. sheet blow-moulding from joined sheets
• CPC Class Codes: B29C 49/18 using several blowing steps B29C49/16 takes precedence
• CPC Class Codes: B29C 49/22 using multilayered preforms or parisons
• CPC Class Codes: B29C 65/028 making use of inherent heat, i.e. the heat for the joining comes from the moulding process of one of the parts to be joined
• CPC Class Codes: B29C 65/565 involving interference fits, e.g. force-fits or press-fits B29C65/66 takes precedence
• CPC Class Codes: B29C 66/112 Single lapped joints
• CPC Class Codes: B29C 66/131 Single flanged joints, i.e. one of the parts to be joined being rigid and flanged in the joint area
• CPC Class Codes: B29C 66/53247 said spouts comprising flanges
• CPC Class Codes: B29C 66/61 Joining from or joining on the inside for making tubes by bending sheets and joining from the inside B29C53/387
• CPC Class Codes: B29C 66/71 characterised by the composition of the plastics material of the parts to be joined welding bar compositions B29C65/125
• CPC Class Codes: B29C 66/723 being multi-layered B29C66/7292, B29C66/72941 take precedence
• CPC Class Codes: B29C 66/7234 comprising a barrier layer
• CPC Class Codes: B29C 70/74 Moulding material on a relatively small portion of the preformed part, e.g. outsert moulding B29C70/845 takes precedence
• CPC Class Codes: B29K 2023/06 PE, i.e. polyethylene
• CPC Class Codes: B29K 2023/065 HDPE, i.e. high density polyethylene
• CPC Class Codes: B29K 2023/086 EVOH, i.e. ethylene vinyl alcohol copolymer
• CPC Class Codes: B29K 2059/00 : Use of polyacetals , e.g. POM, i.e. polyoxymethylene or derivatives thereof, as moulding material
• CPC Class Codes: B29L 2031/7172 : Fuel tanks, jerry cans
• CPC Class Codes: B60K 15/03 : Fuel tanks chassis frame comprising fluid storage compartment B62D21/16 ; Details of the fuel feeding system related to the fuel tank F02M37/0076
• CPC Class Codes: B60K 15/03177 : made of non-metallic material, e.g. plastics, or of a combination of non-metallic and metallic material B60K15/03006 takes precedence
• CPC Class Codes: B60K 2015/03046 : made from more than one layer
• CPC Class Codes: B60K 2015/03453 : for fixing or mounting parts of the fuel tank together
• CPC Class Codes: F16L 47/28 : Joining pipes to walls or to other pipes, the axis of the joined pipe being perpendicular to the wall or to the axis of the other pipe

Abstract

Low permeation fittings and low permeation plastic containers using same are constructed by molding an outer component into the wall of a plastic container while it is being formed. This causes the opening of a passageway in the outer component to be covered with wall forming material. The inner component is then inserted into the outer component through the wall forming material thereby trapping the wall material between the internal and external components. The barrier layer of the container wall is therefore continuous from the container to inside the fitting. A new fuel container, fuel neck fitting, and flange for mounting components on a fuel tank are disclosed.

Claims

1. A container assembly, comprising a fitting and a wall,

said wall defining a container with an interior and an exterior surface, said wall having a fitting portion in said fitting and a container portion forming said container beyond said fitting, and

said fitting comprising an inner component and an outer component, said outer component being bonded at a first end to said wall and having an outer portion that extends outwardly from said exterior surface of said container, at least a portion of said inner component being situated inside of said outer portion of said outer component, wherein said fitting portion of said wall is apposed to said inner component and to said outer component in said outer portion of said outer component, wherein said fitting portion of said wall is continuous with said container portion.

2. The assembly of claim 1, wherein said container wall comprises a layer impermeable to hydrocarbons.

3. The assembly of claim 1, wherein said container is a fuel tank for a vehicle, and said fitting is selected from the group consisting of a fuel inlet fitting, a vapor control valve fitting, and a sender unit attachment fitting.

4. The assembly of claim 1, wherein said outer component comprises high density polyethylene, and said inner component comprises an acetal.

5. The assembly of claim 1, wherein said container wall comprises a layer of ethylene vinyl alcohol copolymer.

6. The assembly of claim 1, wherein said container wall comprises an inner layer of ethylene vinyl copolymer and at least one outer layer of high density polyethylene.

7. The assembly of claim 6, wherein said fitting portion of said wall has an average thickness of between about 1 mm to about 8 mm.

8. The assembly of claim 4, wherein said container wall comprises a layer of ethylene vinyl alcohol copolymer.

9. A method of forming a container, said method comprising the steps of:

bonding at least one exterior fitting component to a wall forming material during formation of the container, said exterior fitting component having an exterior portion and a passageway from said exterior portion to a first end opening, wherein said bonding step causes said first end opening to be covered by said wall forming material, and

inserting an interior fitting component into said exterior fitting component exterior portion via said first end opening to cause said wall forming material to extend into said exterior portion of said exterior fitting component.

10. The method of claim 9, wherein said wall forming material comprises a thermoplastic material.

11. The method of claim 9, wherein said exterior fitting component comprises high density polyethylene.

12. The method of claim 9, wherein said wall forming material comprises a layer of material impermeable to hydrocarbons.

13. The method of claim 9, wherein said wall forming material comprises a layer of ethylene vinyl alcohol copolymer.

14. The method of claim 9, wherein said wall forming material comprises an inner layer of ethylene vinyl alcohol copolymer and at least one outer layer of high density polyethylene.

15. The method of claim 9, wherein said wall forming material comprises a thermoplastic material, said exterior fitting component is bonded to said container wall forming material during thermoplastic forming of said container, and insertion of said interior fitting into said exterior fitting component is used to thermoform said wall forming material into said exterior fitting.

16. The method of claim 9, wherein said container is formed by a process selected from the group consisting of twin sheet thermoforming, and blow molding.

17. The method of claim 15, wherein said inserting step is performed at a temperature between about 360°

F. and about 430°

F.

18. A vehicle fuel tank produced by the process of claim 9.

19. A vehicle fuel tank produced by the process of claim 17.

20. A low permeability fitting for a low permeability container, comprising an inner component, and an outer component, wherein said outer component has a first end for bonding attachment to a low permeability container wall and a second end that extends away from a container wall upon bonding attachment of said first end to a low permeability container wall, said inner component has a first end that may be inserted through said first end of said outer component and into said second end of said outer component, wherein when said first end of said inner component is inserted through said first end of said outer component into said second end of said outer component a gap is defined therebetween sufficient to accommodate a portion of low permeability wall material to which said outer component may be bonded.

21. The fitting of claim 20, wherein said outer component is formed of a material comprising high density polyethylene.

22. The fitting of claim 20, wherein said outer component comprises a first cylinder and said inner component comprises a second cylinder, said first and second cylinders each having a first end and a second end, wherein said first end of said first cylinder comprises a flange that may be bonded to the wall of a container so that said second end of said first cylinder projects outward from the container, said first end of said second cylinder being insertable into said first end of said first cylinder to extend towards said second end of said first cylinder portion, wherein the outer diameter of said first end of said second cylinder is sufficiently smaller than the inner diameter of said first end of said first cylinder to form a gap to accommodate a desired thickness of container wall material, wherein a low permeability wall material may be formed between said second cylinder and said first cylinder by bonding said flange to a low permeability wall material followed by insertion of said first end of said second cylinder into the first end of said first cylinder.

23. The fitting of claim 22, wherein said second cylinder further comprises gripping projections on said first end of said second cylinder to facilitate insertion of low permeability wall material into said first cylinder.

24. A fuel tank inlet fitting, comprising an inner component, and an outer component, wherein said inner component and outer component can cooperate with a portion of a low permeability wall that forms a low permeability fuel storage container to integrally form said fitting to the container, wherein at least a portion of said inner and outer component will extend outwardly of a container to which said fitting may be integrally formed, and wherein, when said fitting is integrally formed to a container, a portion of the container wall is between the portions of said inner component and said outer component that extend outwardly from the container whereby the permeability properties of the storage container wall are extended to the fitting.