Patent US5695497A successfully refreshed from Google Patents.
US6016848A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluoropolymer tubes and methods of making same
Assignee: W.L. Gore and Associates Inc
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Filing: 1997-03-25
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Granted: 2000-01-25
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Expires: 2017-03-25
Abstract
Abstract The present invention relates to fluoropolymer tubes which exhibit excellent properties such as strength, wear resistance and dimensional stability when subjected to repeated flexing due to vibration, bending, or the like.
Inventors
- 👤 Ronald G. Egres, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:01
CPC Classifications
F; F16; F16L; F16L11/00; F16L11/04; F16L11/045; F16L9/00; F16L9/12
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
84 words
A flexible tube of layered expanded PTFE membrane comprising: a first layer of expanded PTFE membrane exhibiting a node and fibril structure comprising an inner surface and an outer surface; at least one subsequent layer of expanded PTFE membrane exhibiting a node and fibril structure comprising an inner surface and an outer surface; wherein each subsequent layer surrounds at least a portion of the outer surface of the immediately preceding layer; and wherein the inner diameter of said tube is greater than 25.4 mm.
Claim 2
Dependent Claim
84 words
A flexible tube of layered expanded PTFE membrane comprising: a first layer of expanded PTFE membrane exhibiting a node and fibril structure comprising an inner surface and an outer surface; at least one subsequent layer of expanded PTFE membrane exhibiting a node and fibril structure comprising an inner surface and an outer surface; wherein each subsequent layer surrounds at least a portion of the outer surface of the immediately preceding layer; and wherein the inner diameter of said tube is greater than 25.4 mm.
Claim 3
Dependent Claim
32 words
The flexible tube of claim 1, wherein said layered expanded PTFE membrane is wrapped in at least one configuration selected from the group consisting of a helical wrap and a coiled wrap.
Claim 4
Dependent Claim
18 words
The flexible tube of claim 1, wherein said tube has a wall thickness of greater than 0.25 mm.
Claim 5
Dependent Claim
40 words
The flexible tube of claim 1, wherein said tube has at least one geometry selected from the group consisting of a uniform diameter from one end of the tube to the other, a frustrum geometry, and a non-uniform patterned geometry.
Claim 6
Dependent Claim
27 words
The flexible tube of claim 1, wherein said tube comprises a flexible connection for connecting at least one set of members selected from conduits, ducts and pipes.
Claim 7
Dependent Claim
26 words
The flexible tube of claim 1, wherein said tube comprises a protective covering to protect components from at least one of thermal, chemical and mechanical stresses.
Claim 8
Dependent Claim
15 words
The flexible tube of claim 1, wherein said tube further comprises at least one filler.
Claim 9
Dependent Claim
29 words
The flexible tube of claim 1, wherein said tube further comprises at least one second material interposed between at least one of the layers of the expanded PTFE membrane.
Claim 10
Dependent Claim
16 words
The flexible tube of claim 1, wherein said tube further comprises at least one reinforcing rib.
Claim 11
Independent Claim
163 words
A method of forming a flexible tube of layered expanded PTFE membrane, comprising: providing a mandrel having a diameter greater than 25.4 mm with an exterior surface and at least one outlet to permit gas to flow to the exterior surface of the mandrel; wrapping at least two layers of expanded PTFE membrane exhibiting a node and fibril structure around the exterior surface of the mandrel; heating said mandrel and said expanded PTFE membrane to a temperature above the crystalline melting point of the fluoropolymer for a time sufficient to induce shrinkage and coalescence of the nodes and fibrils at the surface interface of the at least two layers, whereby said shrinkage and coalescence results in adhesion of the layers into a coherent tube of layered expanded PTFE membrane; blowing at least some gas through said outlet of the mandrel to separate the tube of expanded PTFE from the exterior surface of the mandrel; and removing said expanded PTFE tube from the mandrel.
Claim 12
Independent Claim
163 words
A method of forming a flexible tube of layered expanded PTFE membrane, comprising: providing a mandrel having a diameter greater than 25.4 mm with an exterior surface and at least one outlet to permit gas to flow to the exterior surface of the mandrel; wrapping at least two layers of expanded PTFE membrane exhibiting a node and fibril structure around the exterior surface of the mandrel; heating said mandrel and said expanded PTFE membrane to a temperature above the crystalline melting point of the fluoropolymer for a time sufficient to induce shrinkage and coalescence of the nodes and fibrils at the surface interface of the at least two layers, whereby said shrinkage and coalescence results in adhesion of the layers into a coherent tube of layered expanded PTFE membrane; blowing at least some gas through said outlet of the mandrel to separate the tube of expanded PTFE from the exterior surface of the mandrel; and removing said expanded PTFE tube from the mandrel.
Claim 13
Dependent Claim
33 words
The method of claim 10, wherein said wrapping of the at least two layers of expanded PTFE film is carried out in at least one of a coil wrap and a helical wrap.
Claim 14
Dependent Claim
20 words
The method of claim 10, further comprising providing at least one second material between the layers of expanded PTFE membrane.
Claim 15
Dependent Claim
75 words
A corrugated flexible tube of layered expanded PTFE membrane comprising: a first layer of expanded PTFE membrane comprising an inner surface and an outer surface; at least one subsequent layer of expanded PTFE membrane comprising a inner surface and an outer surface; wherein each subsequent layer surrounds at least a portion of the outer surface of the immediately preceding layer; and wherein said tube includes at least one corrugation in at least a portion thereof.
Claim 16
Dependent Claim
75 words
A corrugated flexible tube of layered expanded PTFE membrane comprising: a first layer of expanded PTFE membrane comprising an inner surface and an outer surface; at least one subsequent layer of expanded PTFE membrane comprising a inner surface and an outer surface; wherein each subsequent layer surrounds at least a portion of the outer surface of the immediately preceding layer; and wherein said tube includes at least one corrugation in at least a portion thereof.
Claim 17
Dependent Claim
33 words
The corrugated flexible tube of claim 13, wherein said layered expanded PTFE membrane is wrapped in at least one configuration selected from the group consisting of a helical wrap and a coiled wrap.
Claim 18
Dependent Claim
16 words
The corrugated flexible tube of claim 13, wherein said expanded PTFE is at least partially densified.
Claim 19
Dependent Claim
32 words
The corrugated flexible tube of claim 13, wherein the at least one corrugation has at least one geometry selected from the group consisting of to angled corrugations, rounded corrugations and squared corrugations.
Claim 20
Dependent Claim
27 words
The corrugated flexible tube of claim 13, wherein the density of the tube varies in one region of the tube relative to another region of the tube.
Claim 21
Dependent Claim
37 words
The corrugated flexible tube of claim 13, wherein said tube further comprises a first end, a middle region and a second end, and wherein said middle region comprises corrugations and said first and second ends are uncorrugated.
Claim 22
Dependent Claim
27 words
The corrugated flexible tube of claim 13, wherein said at least one corrugation is selected from the group consisting of longitudinal corrugations, helical corrugations and circumferential corrugations.
Claim 23
Dependent Claim
16 words
The corrugated flexible tube of claim 13, wherein said tube further comprises at least one filler.
Claim 24
Dependent Claim
30 words
The corrugated flexible tube of claim 13, wherein said tube further comprises at least one second material interposed between at least one of the layers of the expanded PTFE membrane.
Claim 25
Dependent Claim
28 words
The corrugated flexible tube of claim 21, wherein said at least one second material has a lower porosity than the porosity of the layers of expanded PTFE material.
Claim 26
Dependent Claim
46 words
The corrugated flexible tube of claim 21, wherein said at least one second material comprises at least one material selected from the group consisting of FEP, PFA, liquid crystal polymer, and PTFE having a lower porosity than the porosity of the layers of expanded PTFE material.
Claim 27
Dependent Claim
32 words
The corrugated flexible tube of claim 13, wherein said tube comprises a flexible connection for connecting at least one set of members selected from the group consisting of conduits, ducts and pipes.
Claim 28
Dependent Claim
27 words
The corrugated flexible tube of claim 13, wherein said tube comprises a protective covering to protect components from at least one of thermal, chemical and mechanical stresses.
Claim 29
Dependent Claim
22 words
The corrugated flexible tube of claim 21, wherein said at least one second material is present on the exterior of the tube.
Claim 30
Dependent Claim
22 words
The corrugated flexible tube of claim 21, wherein said at least one second material is present on the exterior of the tube.
Claim 31
Dependent Claim
66 words
A corrugated flexible tube comprising an outer region comprising corrugated layers comprising multiple wrapped layers of expanded PTFE membrane; an inner region comprising multiple wrapped layers of expanded PTFE membrane; and at least one layer of a second material sandwiched between and adhered to said outer region and said inner region, wherein said outer region has a lower porosity than the porosity of said inner region.
Claim 32
Dependent Claim
66 words
A corrugated flexible tube comprising an outer region comprising corrugated layers comprising multiple wrapped layers of expanded PTFE membrane; an inner region comprising multiple wrapped layers of expanded PTFE membrane; and at least one layer of a second material sandwiched between and adhered to said outer region and said inner region, wherein said outer region has a lower porosity than the porosity of said inner region.
Claim 33
Dependent Claim
30 words
The corrugated flexible tube of claim 28, wherein said at least one second material comprises at least one material having a porosity lower than the porosity of the outer region.
Claim 34
Dependent Claim
43 words
The corrugated flexible tube of claim 28, wherein said at least one second material comprises at least one material selected from the group consisting of FEP, PFA, liquid crystal polymer, and PTFE having a porosity lower than the porosity of the outer region.
Claim 35
Independent Claim
190 words
A method of forming a corrugated flexible tube of layered fluoropolymer membrane, comprising: providing a mandrel with an exterior surface and at least one outlet to permit gas to flow to the exterior surface of the mandrel; wrapping at least two layers of expanded PTFE membrane exhibiting a node and fibril structure around the exterior surface of the mandrel; heating said mandrel and said expanded PTFE membrane layers to a temperature above the crystalline melting point of the fluoropolymer for a time sufficient to induce shrinkage and coalescence of the nodes and fibrils at the surface interface of the at least two layers, whereby said shrinkage and coalescence results in adhesion of the layers into a coherent tube of layered expanded PTFE membrane; providing a mold having an internal geometry of corrugations spaced outwardly from said mandrel; blowing at least some gas through said outlet of the mandrel to separate the expanded PTFE tube from the exterior surface of the mandrel force the tube into the internal geometry of the mold, thereby forming corrugations in the expanded PTFE tube; and removing said corrugated flexible expanded PTFE tube from the mold.
Claim 36
Independent Claim
190 words
A method of forming a corrugated flexible tube of layered fluoropolymer membrane, comprising: providing a mandrel with an exterior surface and at least one outlet to permit gas to flow to the exterior surface of the mandrel; wrapping at least two layers of expanded PTFE membrane exhibiting a node and fibril structure around the exterior surface of the mandrel; heating said mandrel and said expanded PTFE membrane layers to a temperature above the crystalline melting point of the fluoropolymer for a time sufficient to induce shrinkage and coalescence of the nodes and fibrils at the surface interface of the at least two layers, whereby said shrinkage and coalescence results in adhesion of the layers into a coherent tube of layered expanded PTFE membrane; providing a mold having an internal geometry of corrugations spaced outwardly from said mandrel; blowing at least some gas through said outlet of the mandrel to separate the expanded PTFE tube from the exterior surface of the mandrel force the tube into the internal geometry of the mold, thereby forming corrugations in the expanded PTFE tube; and removing said corrugated flexible expanded PTFE tube from the mold.
Claim 37
Dependent Claim
33 words
The method of claim 31, wherein said wrapping of the at least two layers of expanded PTFE membrane is carried out in at least one of a coil wrap and a helical wrap.
Claim 38
Dependent Claim
23 words
The method of claim 31, further comprising providing at least one second material between two or more of the expanded PTFE membrane layers.
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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) | 2003-01-24 | 2003-07-26 | 2004-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-01-24 | 2007-07-26 | 2008-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-01-24 | 2011-07-26 | 2012-01-25 | $7700.00 | Window Closed / Lapsed |