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US3909893A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for making tubular needlefelted material

Assignee: Individual
•
Filing: 1974-07-15
•
Granted: 1975-10-07
•
Expires: 1994-07-15
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Abstract

Abstract A tubular needlefelted material is formed from a continuous web of fibres which is wound as an overlapping helix to form the tube. As the web is wound parallel reinforcing threads are supplied to wrap the tube. The wound web and threads are needlefelted and the needlefelted tube thus produced is progressively advanced in the direction of the axis of the tube. Preferably the threads lay to one side of the web so as to be located near the inner surface of the finished tube.

Inventors

  • 👤 John Clarke Wilde

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 02:31
CPC Classifications
D; D04; D04H; D04H5/00; D04H5/02; D04H1/00; D04H1/70; D04H1/76; D04H18/00; D04H3/00; D04H3/02; D04H3/07

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 120 words
A process for manufacturing an improved tubular needlefelted material comprising: a. forming a continuous web of fibres of predetermined width; b. feeding the web as a helix to create a tube with adjacent turns of the helix overlapping by a major part of said predetermined width; c. causing a plurality of strengthening strands to wrap said tube helically as the web is fed, said strands occupying a width which is less than said predetermined width of said web; d. needlefelting said tube and strands and e. progressively advancing the needlefelted tube in the direction of the axis of the tube, whereby there is formed a needlefelted tube with helically wound strengthening strands located within the wall thickness of the tube.
Claim 2
Dependent Claim 120 words
A process for manufacturing an improved tubular needlefelted material comprising: a. forming a continuous web of fibres of predetermined width; b. feeding the web as a helix to create a tube with adjacent turns of the helix overlapping by a major part of said predetermined width; c. causing a plurality of strengthening strands to wrap said tube helically as the web is fed, said strands occupying a width which is less than said predetermined width of said web; d. needlefelting said tube and strands and e. progressively advancing the needlefelted tube in the direction of the axis of the tube, whereby there is formed a needlefelted tube with helically wound strengthening strands located within the wall thickness of the tube.
Claim 3
Dependent Claim 12 words
The process of claim 1 in which the strands comprise parallel filaments.
Claim 4
Dependent Claim 14 words
The process of claim 2 in which tHe strands are provided by a tape.
Claim 5
Dependent Claim 13 words
The process of claim 2 in which the strands are provided by scrim.
Claim 6
Dependent Claim 52 words
The process of claim 1 in which the strands are fed, relative to the web of fibres, so as to lay to one side of the web thereby forming a needle felted tube with helically wound strengthening strands which lie nearer to the inside wall of the tube than the outside wall.
Claim 7
Dependent Claim 44 words
The process of claim 1 in which an additional step of causing strengthening strands to wrap said tube helically is performed whereby there is formed a needlefelted tube with helically wound strengthening strands located at two depths within the wall thickness of the tube.
Claim 8
Dependent Claim 15 words
The process of claim 1 in which the carded fibres are of heat shrinkable material.
Claim 9
Dependent Claim 30 words
The process of claim 7 in which the tube formed by the process is cut to produce a sheet and the sheet is heat pressed to flatten and shrink it.
Claim 10
Dependent Claim 23 words
The process of claim 1 in which the needlefelted tube is impregnated by spraying with a substance which adds a desired property thereto.
Claim 11
Dependent Claim 11 words
The process according to claim 9 wherein said substance comprises graphite.
Claim 12
Dependent Claim 11 words
The process according to claim 9 wherein said substance comprises resin.
Claim 13
Dependent Claim 117 words
A process for manufacturing tubular needlefelted material comprising: a. forming a continuous web of base fibres of predetermined width; b. feeding said web over spaced rollers having free ends as a helix with adjacent turns overlapping by a major part of said predetermined width; c. needlefelting the overlapping turns to form a sleeve; d. causing a series of parallel strengthening filaments to wrap said sleeve helically as it is being formed, said filaments occupying a width which is less than said predetermined width of said web; e. needlefelting the wrapped sleeve; and f. causing the sleeve to move axially as web is fed so that the needlefelted wrapped sleeve leaves the rollers at the free ends thereof.
Claim 14
Dependent Claim 117 words
A process for manufacturing tubular needlefelted material comprising: a. forming a continuous web of base fibres of predetermined width; b. feeding said web over spaced rollers having free ends as a helix with adjacent turns overlapping by a major part of said predetermined width; c. needlefelting the overlapping turns to form a sleeve; d. causing a series of parallel strengthening filaments to wrap said sleeve helically as it is being formed, said filaments occupying a width which is less than said predetermined width of said web; e. needlefelting the wrapped sleeve; and f. causing the sleeve to move axially as web is fed so that the needlefelted wrapped sleeve leaves the rollers at the free ends thereof.

References Cited (Backward Citations)

US2748805A Cited
US3424204A Cited
US3375561A Cited
US3477898A Cited
US3673024A Cited
US3758926A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-10-06 1979-04-07 1979-10-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-10-06 1983-04-07 1983-10-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-10-06 1987-04-07 1987-10-07 $7700.00 Window Closed / Lapsed

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