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US3795468A Expired / Lapsed US ⏱️ 0.0 years remaining

Waste recovery of thermoplastic continuous filamentary material

Assignee: Eastman Kodak Co
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Filing: 1972-09-05
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Granted: 1974-03-05
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Expires: 1992-09-05
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Abstract

Abstract Method and apparatus for recovering waste thermoplastic fiber of continuous length filamentary material and converting it into reuseable feed stock and particularly a large otherwise unmanageable, entangled mass of continuous length filamentary material, some or all of which being either drafted or undrafted, wherein the continuous length filamentary material is converted into random length staple fiber, the staple fiber is then mechanically compacted and melted into a melt flow, and the melt flow is finally extruded as the re-useable feed stock; and the resulting product of the method.

Inventors

  • 👤 R Hester
  • 👤 H Pierson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 21:04
CPC Classifications
B; B29; B29B; B29B17/00; B29B17/0026; B29B17/0036; B29C; B29C48/00; B29C48/25; B29C48/275; B29C48/277; B29C48/285; B29C48/287; B29C48/288; B29C48/2886; B29C48/36; B29C48/50; B29C48/505; B29C48/52; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92085; B29C2948/92104; B29C2948/92504; B29C2948/92514; B29C2948/9258; B29C2948/926; B29C2948/92819; B29C2948/92857; B29C2948/92876; B29C48/03; B29C48/05; B29C48/68; B29C48/685; B29C48/72; B29C48/725; B29C48/78; B29C48/793; B29C48/797; B29C48/80; B29C48/802; B29C48/83; B29C48/834; B29K; B29K2105/00; B29K2105/06; B29K2105/12; B29K2105/26; B29L; B29L2031/00; B29L2031/731; Y; Y02; Y02P; Y02P70/00; Y02P70/10; Y02W; Y02W30/00; Y02W30/50; Y02W30/62

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 336 words
In an extruder adapted to receive thermoplastic staple fiber and having a barrel and a feed screw rotatable in the barrel, the barrel at one end having an extrusion die and at the other end having a feed section, the improvement comprising: said feed section defining a. an elongated tangential side opening through which the staple fiber is introduced into the bite of the feed screw, as defined therebetween by the downwardly turning portion of the feed screw and the interior wall of the barrel within which the feed screw revolves, thereby entrapping the staple fiber on the underside of the feed screw; and b. a downwardly inclined surface extending from the elongated tangential side opening toward the bite of the feed screw and adapted to conduct the staple fiber into the bite when the staple fiber is introduced into the side opening; said feed section including therewithin means for preventing the staple fiber from rotating with the feed screw and thereby enabling and assuring continuous forward movement of the staple fiber from the feed section, the latter recited means including surfaces extending radially inwardly from the interior wall of the feed section and being circumferentially spaced apart and adapted to cooperate with the flights on the feed screw to keep the movement of the staple fiber perpendicular to the screw flights; said barrel being jacketed and provided with heating means along its length and having means for internally cooling the feed section so that the interior wall surface of the feed section with whiCh the fiber comes into contact is below the temperature at which the staple fiber would tend to stick to the interior wall surface; and said feed screw having substantially coextensive with the tangential side opening a first section having a root diameter of constant size, the interior wall surface adjacent to the first section and to the side opening tapering inwardly toward the feed screw and thereby adapted in cooperation with the feed screw to initiate compression of the staple fiber.
Claim 2
Dependent Claim 336 words
In an extruder adapted to receive thermoplastic staple fiber and having a barrel and a feed screw rotatable in the barrel, the barrel at one end having an extrusion die and at the other end having a feed section, the improvement comprising: said feed section defining a. an elongated tangential side opening through which the staple fiber is introduced into the bite of the feed screw, as defined therebetween by the downwardly turning portion of the feed screw and the interior wall of the barrel within which the feed screw revolves, thereby entrapping the staple fiber on the underside of the feed screw; and b. a downwardly inclined surface extending from the elongated tangential side opening toward the bite of the feed screw and adapted to conduct the staple fiber into the bite when the staple fiber is introduced into the side opening; said feed section including therewithin means for preventing the staple fiber from rotating with the feed screw and thereby enabling and assuring continuous forward movement of the staple fiber from the feed section, the latter recited means including surfaces extending radially inwardly from the interior wall of the feed section and being circumferentially spaced apart and adapted to cooperate with the flights on the feed screw to keep the movement of the staple fiber perpendicular to the screw flights; said barrel being jacketed and provided with heating means along its length and having means for internally cooling the feed section so that the interior wall surface of the feed section with whiCh the fiber comes into contact is below the temperature at which the staple fiber would tend to stick to the interior wall surface; and said feed screw having substantially coextensive with the tangential side opening a first section having a root diameter of constant size, the interior wall surface adjacent to the first section and to the side opening tapering inwardly toward the feed screw and thereby adapted in cooperation with the feed screw to initiate compression of the staple fiber.
Claim 3
Dependent Claim 68 words
In an extruder according to claim 1 and wherein said surfaces extending radially inwardly from the interior wall of the feed section comprises a keyed section spaced from the feed screw, the keyed section initially spiralling partly around and along a portion of the length of the feed section and then straightening out to extend parallel to and for the remainder of the length of the feed section.
Claim 4
Dependent Claim 101 words
In an extruder according to claim 1 and wherein said means for preventing the staple fiber from rotating includes a removable insert positioned within the barrel, the removable insert forming the interior wall of the feed section; and wherein said surfaces extending radially inwardly from the interior wall of the feed section comprise a plurality of keyed wedges spaced from the feed screw, the keyed wedges each initially spiralling partly around and along a portion of the length of the feed section and then straightening out to extend parallel to and for the remainder of the length of the feed section.
Claim 5
Dependent Claim 25 words
In an extruder according to claim 1 and wherein said tangential side opening has a length about three times the diameter of the feed screw.

References Cited (Backward Citations)

US23880A Cited
US760481A Cited
US1427272A Cited
US1604799A Cited
US2200997A Cited
US2786505A Cited
US3101511A Cited
US3431599A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1977-03-04 1977-09-03 1978-03-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1981-03-04 1981-09-03 1982-03-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1985-03-04 1985-09-03 1986-03-05 $7700.00 Window Closed / Lapsed

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