Patent US4124678A successfully refreshed from Google Patents.
US4124678A
Expired / Lapsed
US
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Method of making tortuous tubular articles
Assignee: Sipler Plastics Inc
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Filing: 1977-12-29
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Granted: 1978-11-07
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Expires: 1997-12-29
Abstract
Abstract Method for making tubular articles of tortuous configuration and of resin impregnated material. The method is intended to avoid resin-starved areas in the product. Specifically, tubular articles having high curvature, sharp transitions in cross section size and/or shape and close tolerance ends are provided these being made by applying and incorporating selectively placed porous components. The article is formed in a mold by an inflatable mandrel which carries a continuous, surrounding knitted fabric component and one or more localized foam, felt and/or fabric devices of porous nature which control the supply, flow and/or final disposition of resin matrix in the molding process.
Inventors
- 👤 James D. Stroupe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:23
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/04; B29C70/28; B29C70/54; B29C70/546; B29C70/547; B29C49/00; B29C49/42; B29C49/44; B29C70/02; B29C70/30; B29C70/34; B29C70/342; B29C70/40; B29C70/42; B29C70/44; B29C70/446; F; F16; F16L; F16L11/00; F16L11/04; F16L11/12; B29C43/00; B29C43/02; B29C43/10; B29C43/12; B29K; B29K2105/00; B29K2105/04; B29K2105/06; B29K2105/08; B29K2105/0809; B29K2105/0854; B29L; B29L2031/00; B29L2031/24; B29L2031/243
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
233 words
The method of making a unitary hollow rigid tubular article by air displacement in a mold which comprises: mounting on an expansible and flexible core tube a thermosetting resin containing compressible element in at least partial covering relation to the core tube; mounting in covering relation to said element and in surrounding relation to the core tube an elongated circumferentially expansible seamless knitted fabric tube of a continuous length corresponding to a desired length of the finished article; applying locally in at least partial covering relation to said fabric tube, adjacent abrupt changes in tube configuration, a porous, compressible member to control flow of resin and air; inserting the expansible tube with assembled layers into an elongated smooth cavity in a mold which cavity has a fixed torous non-planar longitudinal configuration and a variable cross sectional area along the length thereof and is shaped to conform to a desired exterior shape of the finished article, expanding the core tube to compress resin from the resin containing element and expanding and distorting the fabric tube thereon to conform to the elongated mold cavity by pressure applied by the core tube and by the expansion forcing displacement of air and distribution of the resin into the interstices of the fabric tube and the compressible member, curing the resin by heat in the mold, removing the formed assembly from the mold, and removing the core tube.
Claim 2
Independent Claim
233 words
The method of making a unitary hollow rigid tubular article by air displacement in a mold which comprises: mounting on an expansible and flexible core tube a thermosetting resin containing compressible element in at least partial covering relation to the core tube; mounting in covering relation to said element and in surrounding relation to the core tube an elongated circumferentially expansible seamless knitted fabric tube of a continuous length corresponding to a desired length of the finished article; applying locally in at least partial covering relation to said fabric tube, adjacent abrupt changes in tube configuration, a porous, compressible member to control flow of resin and air; inserting the expansible tube with assembled layers into an elongated smooth cavity in a mold which cavity has a fixed torous non-planar longitudinal configuration and a variable cross sectional area along the length thereof and is shaped to conform to a desired exterior shape of the finished article, expanding the core tube to compress resin from the resin containing element and expanding and distorting the fabric tube thereon to conform to the elongated mold cavity by pressure applied by the core tube and by the expansion forcing displacement of air and distribution of the resin into the interstices of the fabric tube and the compressible member, curing the resin by heat in the mold, removing the formed assembly from the mold, and removing the core tube.
Claim 3
Dependent Claim
19 words
The method defined in claim 1 in which said compressible element is an open pore stabilized compressible synthetic foam.
Claim 4
Dependent Claim
14 words
The method defined in claim 1 in which the fabric tube is rib knit.
Claim 5
Dependent Claim
36 words
The method defined in claim 1 in which said air flow restricting member is disposed in partial longitudinal intersecting relation to at least one of the mold parting lines and is in contact with the mold.
Claim 6
Dependent Claim
21 words
The method defined in claim 1 in which at least one additional knitted fabric tube is applied onto said fabric tube.
Claim 7
Dependent Claim
20 words
The method defined in claim 5 in which additional thermosetting resin is applied to the outer of said knitted tubes.
Claim 8
Dependent Claim
20 words
The method of claim 1 wherein said compressible member is a fibrous mat of low resin capacity and low compressibility.
Claim 9
Dependent Claim
20 words
The method of claim 7 wherein said compressible member is a fibrous felt of low resin capacity and low compressibility.
Claim 10
Dependent Claim
24 words
The method defined in claim 1 in which the length of said resin containing element is less than the length of the finished article.
Claim 11
Dependent Claim
16 words
The method defined in claim 9 in which the compressible element is of elongated tubular shape.
Claim 12
Dependent Claim
16 words
The method defined in claim 9 in which the compressible element has longitudinally disposed overlapping edges.
Claim 13
Dependent Claim
18 words
The method defined in claim 9 in which the compressible element has its edges disposed in spaced relation.
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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) | 1981-11-06 | 1982-05-08 | 1982-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-06 | 1986-05-08 | 1986-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-06 | 1990-05-08 | 1990-11-07 | $7700.00 | Window Closed / Lapsed |