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US5038833A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel line for fixed-length vehicle installation

Assignee: Technoflow Tube Systems GmbH
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Filing: 1987-06-19
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Granted: 1991-08-13
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Expires: 2007-06-19
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Abstract

Abstract A fixed-length fuel line, for automotive vehicles to be powered by an alcohol-containing fuel such as gasohol, has a relatively thick polyamide wall which is internally lined by a polyvinyl alcohol based alcohol-barrier layer protected against the fuel by a water-barrier layer, e.g. of polyamide, the line being constructed so that swelling of the water-barrier layer does not change the length of the line because any swelling stress is taken up by the thicker polyamide wall.

Inventors

  • 👤 Erwin Brunnnhofer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 22:34
CPC Classifications
F; F16; F16L; F16L11/00; F16L11/04; F16L11/12; F02; F02B; F02B1/00; F02B1/02; F02B1/04; F16L2011/047; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1379; Y10T428/1383; Y10T428/139; Y10T428/1393

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 86 words
The combination with a vehicle fuel system for a vehicle adapted to operate on an alcohol-containing fuel of a fixed-length fuel line which consists of a polyamide wall internally lined with a polyvinyl alcohol based alcohol-barrier layer which is internally lined with a water-barrier layer selected from nylon 11 or nylon 12, said layers being bonded by coextrusion with one another and said wall, the polyamide wall having a thickness sufficient to prevent length changes in said fuel line resulting from swelling of said water-barrier layer.
Claim 2
Dependent Claim 86 words
The combination with a vehicle fuel system for a vehicle adapted to operate on an alcohol-containing fuel of a fixed-length fuel line which consists of a polyamide wall internally lined with a polyvinyl alcohol based alcohol-barrier layer which is internally lined with a water-barrier layer selected from nylon 11 or nylon 12, said layers being bonded by coextrusion with one another and said wall, the polyamide wall having a thickness sufficient to prevent length changes in said fuel line resulting from swelling of said water-barrier layer.
Claim 3
Dependent Claim 19 words
The fuel line defined in claim 1 wherein said polyamide wall is composed of nylon 11 or nylon 12.
Claim 4
Dependent Claim 22 words
The fuel line defined in claim 1 wherein said alcohol-barrier layer is composed of an extrudable copolymer comprised substantially of polyvinyl alcohol.
Claim 5
Dependent Claim 18 words
The fuel line defined in claim 3 wherein said copolymer is a copolymer of vinyl alcohol and ethylene.
Claim 6
Dependent Claim 20 words
The fuel line defined in claim 1 wherein said water-barrier layer is composed of the same material as said wall.
Claim 7
Dependent Claim 20 words
The fuel line defined in claim 1 wherein said polyamide wall has a thickness of substantially 0.75 to 1.25 mm.
Claim 8
Dependent Claim 25 words
The fuel line defined in claim 6 wherein each of said layers has a thickness of substantially 10% of the thickness of said polyamide wall.
Claim 9
Dependent Claim 19 words
The fuel line defined in claim 6 wherein each of said layers has a thickness of substantially 0.1 mm.
Claim 10
Dependent Claim 18 words
The fuel line defined in claim 8 wherein said polyamide wall has a thickness of substantially 0.8 mm.
Claim 11
Dependent Claim 18 words
The fuel line defined in claim 9 wherein said line has an outer diameter of about 8 mm.
Claim 12
Dependent Claim 14 words
The fuel line defined in claim 1 wherein said polyamide wall is hard polyamide.
Claim 13
Dependent Claim 27 words
The fuel line defined in claim 1 wherein said polyamide wall is composed of a polyamide composition containing a plasticizer for polyamide whereby said line is flexible.
Claim 14
Independent Claim 62 words
A method of preventing length-change in a fuel line for an automotive vehicle to be powered by alcohol-containing fuel which comprises the steps of lining a polyamide wall of said fuel line with a layer of polyvinyl alcohol based alcohol-barrier material and separating said alcohol-barrier material from the fuel in said line by a polyamide-water barrier of nylon 11 and nylon 12.
Claim 15
Independent Claim 62 words
A method of preventing length-change in a fuel line for an automotive vehicle to be powered by alcohol-containing fuel which comprises the steps of lining a polyamide wall of said fuel line with a layer of polyvinyl alcohol based alcohol-barrier material and separating said alcohol-barrier material from the fuel in said line by a polyamide-water barrier of nylon 11 and nylon 12.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-08-12 1995-02-11 1995-08-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-08-12 1999-02-11 1999-08-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-08-12 2003-02-11 2003-08-13 $7700.00 Window Closed / Lapsed

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