US3036357A - Crimping apparatus and method - Google Patents

Crimping apparatus and method Download PDF

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Publication number
US3036357A
US3036357A US797153A US79715359A US3036357A US 3036357 A US3036357 A US 3036357A US 797153 A US797153 A US 797153A US 79715359 A US79715359 A US 79715359A US 3036357 A US3036357 A US 3036357A
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United States
Prior art keywords
tow
crimping
belt
filaments
crimp
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Expired - Lifetime
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US797153A
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English (en)
Inventor
Harry M Cook
Jr James F Ryan
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EIDP Inc
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EI Du Pont de Nemours and Co
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Publication date
Priority to NL112601D priority Critical patent/NL112601C/xx
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Priority to US797153A priority patent/US3036357A/en
Priority to BE587928A priority patent/BE587928A/fr
Application granted granted Critical
Publication of US3036357A publication Critical patent/US3036357A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • D—TEXTILES; PAPER
    • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
    • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
    • D02G1/00—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics
    • D02G1/12—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics using stuffer boxes

Definitions

  • This invention relates to a method and apparatus for crimping heavy denier bundles of continuous filament synthetic fibers.
  • Synthetic staple fibers are prepared by cutting or breaking a continuous filament tow. In order that these staple fibers may be readily converted to spun yarns, they must exhibit a finite degree of crimp. This crimp is most advantageously applied to the fiber while it is still in the continuous filament tow form. The tow is crimped continuously and is then cut into staple of the desired length.
  • One common method used for imparting crimp to a tow of continuous filaments is to force the tow into a chamber in which the individual filaments are buckled against a mass of tow already present in the chamber and to remove the crimped product from the chamber when the pressure of the mass exceeds a certain limit.
  • This method produces a very uniform crimp but has the disadvantage that the bends in an individual fiber lie in a single plane.
  • a further disadvantage of this process is that it damages the fibers and reduces their tensile strength.
  • a further advantage of fibers with crimp in the form of convolutions is that they produce fabrics of softer handle than those prepared from fibers with cr'tnp in the form of sharp bends.
  • a further object is to provide apparatus suitable for imparting a three-dimensional convoluted crimp to'synthetic tows.
  • the objects of the invention are attained by passing a tow of synthetic filaments at a regulated speed through a confining tube while simultaneously introducing into said tube a heated gas under pressure, maintaining the contact of heated gas and filaments through a path sufficiently long to raise the temperature of the filaments to a point at which crimping takes place above their second order transition temperature but below their melting or de radation temperature, and ejecting the filaments into a confined space, one side of which is made up by a moving surface.
  • FIG- URE l is a diagrammatic showing of a suitable arrange- Patented May 29, 1952 ment for feeding, crimping and collecting continuous filament tow in accordance with the invention
  • FIGURE 2 is a cross-sectional elevation of a preferred form of crimper
  • FIGURE 3 is a side view of the restraining device or shoe which makes up part of the crimper.
  • a tow 11 of synthetic fibers is withdrawn from a container 12 through a guide 13 by means of positively driven feed rolls 14 rotating at a predetermined constant speed.
  • the tow then passes into the upper end of the crimping device 15 which is provided with steam or other hot compressible fluid through inlets 16 and 17 and thence into the confined volume defined by the steaming shoe 18 and the moving belt 19.
  • the belt travels in the direction indicated between rolls 20 and 21, one of which is driven at a surface speed less than that of roll 14.
  • the crimped tow issuing from the outlet of shoe 18 may be cooled or dried as desired by passing cool or hot air or other medium through the funnelshaped device 22, this air entering or being exhausted through opening 23 in said device.
  • the crimped tow 24 falling from theend of the belt is collected by gravity in container 25.
  • the nozzle 27 is adjustably mounted in supporting element 30 by a screw thread connection.
  • the edges of the upper opening 26 of this nozzle are rounded to prevent damage to the tow.
  • the lower end of the nozzle is beveled so that the position of the nozzle relative to the supporting member will vary the annular opening 29 between the two.
  • a fluid, particularly steam, enters the supporting member through the threaded inlet 16, filling the chamber 31 before passing through the annular opening 29.
  • the nozzle 27 is held in its desired position by means of the lock nut 32.
  • a second nozzle 33 is held in place in the tow exit end of the supporting element 30 by a threaded connection.
  • Adjustably attached to nozzle .33 by means of screw threads is the member .34.
  • This member is equipped with a second threaded inlet 17 for the introduction of steam or other fluid.
  • the fluid enters the chamber 39 before passing downward through the annular space 37 between the tapered lower end of nozzle 33 and the member 34, this armular opening being adjust-able because of the threaded connection between the two-members and capable of being set in a given position with the aid of lock nut 35.
  • the fluid and tow pass downward through openingSS in the tubular lower end of member 34.
  • the confining shoe 18 is attached to the lower end of member 34 by means of the cylindrical collar 40 pro- Example I
  • the starting material for this run was a 50,000 denier wet continuous filament tow of drawn filaments of about 6 denier per filament size prepared from a copolymer of 94% acrylonitrile and 6% methyl acrylate. This tow was drawn from the container 12 by the feed roll 14 at a linear speed of feet per minute and fed into the crimping device 15.
  • the inner diameter of the two nozzles 27 and 33 of the crimping device was A inch.
  • the taper at the output end of each of these nozzles was 20 and the openings between these nozzles and the surrounding members was that given by raising each nozzle inch from its closed position.
  • the steaming shoe 18 had a height of 1 4 inch, a width of "/3 inch at the top and a width of 2% inches at the bottom, it was 4 inches in length with the opening for the admission of the tow at a point 1 inch from the closed end.
  • Thebelt on which the crimped tow impinged was traveling at a rate of 19' feet per minute.
  • the length of belt from the exit end of the steaming shoe to the point of discharge of the crimped tow was 3 6 inches. No gaseous medium was passed through the funnel 22 in this run.
  • the crimped tow falling from the belt 19 was collected in the receptacle 25. This tow was free of large loops and showed no tendency to tangle.
  • the tow was removed from the receptacle 25'and cut to Z /-inch lengths using a yarn cutter of the type described in Cook, U.S.P. 2,747,663.
  • This staple was dried in trays at 127 C. for 15 minutes.
  • the staple was readily processed into jersey-knit fabric of desirable
  • a second run was carried out under identical conditions to those of Example I except that the steam entering opening 17 of the crimping device was under a pressure of 150 pounds per square inch gauge and no steam was introduced through opening 16.
  • the apparatus functioned satisfactorily and produced a crimped product free of large loops and with no tendency toward tangling. After cutting and drying the staple was readily processed into jerscy knit fabric of desirable aesthetic properties.
  • Example III The crimping device used in this experiment was a single-stage device of the type shown in US. 2,379,824 except that a steaming shoe described in Example I was attached to the exit end of the device just above the collecting belt. Steam was fed into the device at a pressure of 100 pounds per square inch gauge. A tow of polyethylene terephthalate filaments having'a total denier of 62,000 and an individual filament denier of 1.5 was fed into this device at a speed of 123 yards per minute. The belt on which the crimped tow impinged traveled at a rate of 53 feet per minute. The product obtained was readily processed through a staple cutter without tangling.
  • the cut staple was readily converted into spun yarns which were used to make woven fabrics of desirable aesthetics.
  • the process of our invention is applicable not only to the fibers described in the examples but also to other synthetic fibers such as poly(epsilon caproamide), celluloseesters, polyethylene, polypropylene, polyvinyl chloride, poly(trans-para-hexahydroxylylene terephthalate), or polyethylene terephthalate/isophthalate.
  • synthetic fibers such as poly(epsilon caproamide), celluloseesters, polyethylene, polypropylene, polyvinyl chloride, poly(trans-para-hexahydroxylylene terephthalate), or polyethylene terephthalate/isophthalate.
  • the tow may be fed to the crimping apparatus from a container as indicated or it may be fed to the feed rolls directly from a spinning machine or a drawing ma-
  • the size of the tow may be varied within wide depending upon production requirements. With tows of various sizes, it is necessary to alter the internal dimensions of the crimping apparatus. Thus, for an acrylic fiber tow of about-500,000 denier, nozzles having an internal diameter of inch have been found to be useful. Withheavy denier tows it is sometimes desirable to use apparatus which is rectangular in internal crosssection in order to give the fluid which. contacts the tow 4 in the apparatus the greatest opportunity to penetrate to the fibers near the center of the tow;
  • crimp frequency, crimp uniformity, and openness of the tow bundle may be obtained by utilizing apparatus in which the section immediately following the final jet increases in internal area in stepwise fashion in the direction of tow travel.
  • the crimp frequency and the permanence of the crimp will depend also on the speed of the belt relative to the input speed and on the dimensions of the steaming shoe. Shoes of larger crossseotional area and greater length are desirable for tow bundles of greater denier.
  • Fluids other than steam such as air, vapors of inert liquids and the like are sometimes of advantage in the crimping process.
  • the temperature of these gases should be sufficiently high to bring the temperature of the filament bundle above the second-order transition of the polymer from which the filaments are made the short time it takes for them to be delivered to the belt.
  • the contact of the fibers with the heated fluid in the apparatus brings about a certain degree of fiber relaxation which would otherwise have to be developed by a separate operation or by use of increased drier temperature.
  • the present crimping process produces a tow which can be dried with much less critical control of the drier temperature.
  • the length of the belt used to collect and discharge the crimped tow will depend on the properties of the individual tow. For different starting materials it may be desirable to use additional cooling or heating by auxiliary means while the tow is on the belt in order to reduce the length of belt travel.
  • the belt may discharge the product into a receptable as previously shown or may desirably discharge the material onto the moving belt of a drying apparatus.
  • the tow may be out directly into staple fibers which have desirable properties for conversion into spun yarns by the usual cotton system and wool system operations.
  • the tow may likewise be used directly in those operations which convert it to silver through breaking or staggered cutting operations. These slivers are in turn converted into spun yarns through commonly used textile processing operations.
  • the spun yarns may be converted into knit fabrics or woven fabrics in the usual way and these fabrics are found to possess desirable softness of a degree not attainable with yarns prepared from fibers of the same filament denier which have'been crimped by the mechanical crimping devices of the prior art. 7
  • Apparatus for crimping continuous synthetic linear filaments which comprises a nozzle, means for passing a bundle of filaments through the nozzle, a housing around the nozzle, means for supplying steam to the said housing, a tube below the said nozzle, an annular space between the nozzle and the said tube, connecting means between the housing and the said annular space for delivering steam through the annular space into the tube, a moving belt at the exit end of the said tube, and a shoe having an inlet through which the exit end of the said tube passes and delivers the yarn passing therethrough onto the said moving belt.
  • Apparatus for crimping a bundle of continuous linear synthetic filaments which comprises a tube, means for introducing the said bundle into the tube at a controlled rate, means for introducing a compressible fiui'd under pressure into the tube, a moving belt at the exit end of the said tube and a housing surrounding the immediate space above the said moving belt, and means for feeding the said bundle through the tube at a rate greater than that of the moving belt.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
US797153A 1959-03-04 1959-03-04 Crimping apparatus and method Expired - Lifetime US3036357A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
NL112601D NL112601C (en)van) 1959-03-04
US797153A US3036357A (en) 1959-03-04 1959-03-04 Crimping apparatus and method
BE587928A BE587928A (fr) 1959-03-04 1960-02-23 Procédé et appareil pour le traitement de fibres synthétiques.

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Cited By (34)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3093878A (en) * 1961-10-16 1963-06-18 Carl Nuissl Air jet for producing bulked stub yarn
US3099064A (en) * 1961-04-13 1963-07-30 Eastman Kodak Co Method and apparatus for making rug yarn
US3116589A (en) * 1961-12-21 1964-01-07 Du Pont Process for forming a slub yarn
US3152379A (en) * 1962-05-29 1964-10-13 American Cyanamid Co Tow crimper closure
US3152380A (en) * 1961-05-05 1964-10-13 Du Pont Process for treating polypropylene fibers
US3166820A (en) * 1960-03-04 1965-01-26 Glanzstoff Ag Process and apparatus for drying and fixing bands of crimped synthetic threads
US3167845A (en) * 1960-07-19 1965-02-02 Du Pont Bulk yarn process and apparatus
US3188713A (en) * 1963-05-06 1965-06-15 Eastman Kodak Co Apparatus for processing crosssection yarn
US3255508A (en) * 1959-06-02 1966-06-14 Du Pont Apparatus for crimping textile yarn
US3258825A (en) * 1962-03-26 1966-07-05 Eastman Kodak Co Methods for the production of highshrink modacrylic yarn
US3259954A (en) * 1965-01-25 1966-07-12 Eastman Kodak Co Apparatus for jet processing multifilaments
US3262181A (en) * 1963-11-22 1966-07-26 Eastman Kodak Co Method for opening fibrous tow
US3296677A (en) * 1963-05-20 1967-01-10 Eastman Kodak Co Crimping apparatus and process
US3300831A (en) * 1963-06-14 1967-01-31 British Nylon Spinners Ltd Crimping of textile fibres
US3334161A (en) * 1965-02-10 1967-08-01 Du Pont Filament forwarding jet device
US3339250A (en) * 1962-05-29 1967-09-05 American Cyanamid Co Crimping fibers
US3341914A (en) * 1964-07-22 1967-09-19 British Nylon Spinners Ltd Process for treating filamentary material in a fluid
US3343240A (en) * 1963-12-27 1967-09-26 Snia Viscosa Method and apparatus for bulking synthetic fibers
US3373470A (en) * 1961-02-08 1968-03-19 Rhodiaceta Process for crimping yarn
US3402970A (en) * 1967-08-22 1968-09-24 Grace W R & Co Venturi loading system
US3409956A (en) * 1966-07-05 1968-11-12 Allied Chem Apparatus and process for texturizing yarn
US3413697A (en) * 1966-02-28 1968-12-03 Eastman Kodak Co Apparatus for production of high-shrink yarn
US3457611A (en) * 1967-10-10 1969-07-29 Hercules Inc Apparatus for crimping thermoplastic yarns
US3471911A (en) * 1968-12-05 1969-10-14 Hercules Inc Process for crimping thermoplastic yarns
US3477218A (en) * 1966-07-21 1969-11-11 Courtaulds Ltd Apparatus and method for producing crimped filamentary materials
US3543358A (en) * 1967-10-24 1970-12-01 Du Pont Process for increasing the bulk of multifilament yarn
DE2512601A1 (de) * 1974-03-22 1975-09-25 Rhone Poulenc Textile Verfahren zur texturierung von polyestergarn und danach hergestelltes garn
US4069562A (en) * 1976-06-28 1978-01-24 Glen Raven Mills, Inc. Apparatus for producing interlaced or entangled multifilament yarns
US4190095A (en) * 1976-10-28 1980-02-26 Allied Chemical Corporation Chill roll casting of continuous filament
US4531965A (en) * 1981-11-07 1985-07-30 Siegfried Aktiengesellschaft Weed control method and composition
US4802268A (en) * 1974-11-26 1989-02-07 Allied-Signal Inc. Apparatus for texturizing yarn
US4863029A (en) * 1987-11-16 1989-09-05 E. I. Du Pont De Nemours And Company Apparatus and process for packaging yarn and product therefrom
US4936001A (en) * 1987-11-16 1990-06-26 Koskol Joseph E Apparatus and process for packaging continuously connected lengths of compacted yarn
US4956901A (en) * 1987-11-16 1990-09-18 E. I. Du Pont De Nemours And Company Apparatus and process for forming a wad of yarn

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2379824A (en) * 1943-03-06 1945-07-03 Du Pont Process and apparatus for treating artificial filaments
US2435891A (en) * 1941-06-24 1948-02-10 American Viscose Corp Method and apparatus for crimping textile fibrous material
US2622306A (en) * 1950-04-25 1952-12-23 Owens Corning Fiberglass Corp Strand blower
US2852906A (en) * 1951-12-14 1958-09-23 Du Pont Method and apparatus for producing bulky continuous filament yarn

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2435891A (en) * 1941-06-24 1948-02-10 American Viscose Corp Method and apparatus for crimping textile fibrous material
US2379824A (en) * 1943-03-06 1945-07-03 Du Pont Process and apparatus for treating artificial filaments
US2622306A (en) * 1950-04-25 1952-12-23 Owens Corning Fiberglass Corp Strand blower
US2852906A (en) * 1951-12-14 1958-09-23 Du Pont Method and apparatus for producing bulky continuous filament yarn

Cited By (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3255508A (en) * 1959-06-02 1966-06-14 Du Pont Apparatus for crimping textile yarn
US3166820A (en) * 1960-03-04 1965-01-26 Glanzstoff Ag Process and apparatus for drying and fixing bands of crimped synthetic threads
US3167845A (en) * 1960-07-19 1965-02-02 Du Pont Bulk yarn process and apparatus
US3373470A (en) * 1961-02-08 1968-03-19 Rhodiaceta Process for crimping yarn
US3099064A (en) * 1961-04-13 1963-07-30 Eastman Kodak Co Method and apparatus for making rug yarn
US3152380A (en) * 1961-05-05 1964-10-13 Du Pont Process for treating polypropylene fibers
US3093878A (en) * 1961-10-16 1963-06-18 Carl Nuissl Air jet for producing bulked stub yarn
US3116589A (en) * 1961-12-21 1964-01-07 Du Pont Process for forming a slub yarn
US3258825A (en) * 1962-03-26 1966-07-05 Eastman Kodak Co Methods for the production of highshrink modacrylic yarn
US3339250A (en) * 1962-05-29 1967-09-05 American Cyanamid Co Crimping fibers
US3152379A (en) * 1962-05-29 1964-10-13 American Cyanamid Co Tow crimper closure
US3188713A (en) * 1963-05-06 1965-06-15 Eastman Kodak Co Apparatus for processing crosssection yarn
US3296677A (en) * 1963-05-20 1967-01-10 Eastman Kodak Co Crimping apparatus and process
US3300831A (en) * 1963-06-14 1967-01-31 British Nylon Spinners Ltd Crimping of textile fibres
US3262181A (en) * 1963-11-22 1966-07-26 Eastman Kodak Co Method for opening fibrous tow
US3343240A (en) * 1963-12-27 1967-09-26 Snia Viscosa Method and apparatus for bulking synthetic fibers
US3341914A (en) * 1964-07-22 1967-09-19 British Nylon Spinners Ltd Process for treating filamentary material in a fluid
US3259954A (en) * 1965-01-25 1966-07-12 Eastman Kodak Co Apparatus for jet processing multifilaments
US3334161A (en) * 1965-02-10 1967-08-01 Du Pont Filament forwarding jet device
US3413697A (en) * 1966-02-28 1968-12-03 Eastman Kodak Co Apparatus for production of high-shrink yarn
US3409956A (en) * 1966-07-05 1968-11-12 Allied Chem Apparatus and process for texturizing yarn
US3477218A (en) * 1966-07-21 1969-11-11 Courtaulds Ltd Apparatus and method for producing crimped filamentary materials
US3402970A (en) * 1967-08-22 1968-09-24 Grace W R & Co Venturi loading system
US3457611A (en) * 1967-10-10 1969-07-29 Hercules Inc Apparatus for crimping thermoplastic yarns
US3543358A (en) * 1967-10-24 1970-12-01 Du Pont Process for increasing the bulk of multifilament yarn
US3471911A (en) * 1968-12-05 1969-10-14 Hercules Inc Process for crimping thermoplastic yarns
DE2512601A1 (de) * 1974-03-22 1975-09-25 Rhone Poulenc Textile Verfahren zur texturierung von polyestergarn und danach hergestelltes garn
US4175157A (en) * 1974-03-22 1979-11-20 Rhone-Poulenc Textile Process for texturizing polyester yarn and yarn
US4802268A (en) * 1974-11-26 1989-02-07 Allied-Signal Inc. Apparatus for texturizing yarn
US4069562A (en) * 1976-06-28 1978-01-24 Glen Raven Mills, Inc. Apparatus for producing interlaced or entangled multifilament yarns
US4069564A (en) * 1976-06-28 1978-01-24 Glen Raven Mills, Inc. Process for producing interlaced or entangled multifilament yarns
US4190095A (en) * 1976-10-28 1980-02-26 Allied Chemical Corporation Chill roll casting of continuous filament
US4531965A (en) * 1981-11-07 1985-07-30 Siegfried Aktiengesellschaft Weed control method and composition
US4863029A (en) * 1987-11-16 1989-09-05 E. I. Du Pont De Nemours And Company Apparatus and process for packaging yarn and product therefrom
US4936001A (en) * 1987-11-16 1990-06-26 Koskol Joseph E Apparatus and process for packaging continuously connected lengths of compacted yarn
EP0316862A3 (en) * 1987-11-16 1990-07-18 E.I. Du Pont De Nemours And Company Apparatus and process for packaging yarn and product therefrom
US4956901A (en) * 1987-11-16 1990-09-18 E. I. Du Pont De Nemours And Company Apparatus and process for forming a wad of yarn

Also Published As

Publication number Publication date
NL112601C (en)van)
BE587928A (fr) 1960-08-23

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