US3304593A - Yarn bulking method and apparatus - Google Patents

Yarn bulking method and apparatus Download PDF

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Publication number
US3304593A
US3304593A US427021A US42702165A US3304593A US 3304593 A US3304593 A US 3304593A US 427021 A US427021 A US 427021A US 42702165 A US42702165 A US 42702165A US 3304593 A US3304593 A US 3304593A
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US
United States
Prior art keywords
yarn
head
crimping
over
bulking
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Expired - Lifetime
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US427021A
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English (en)
Inventor
Glenn A Burklund
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BURKLUND LAB Inc
BURKLUND LABORATORIES Inc
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BURKLUND LAB Inc
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Priority to US427021A priority Critical patent/US3304593A/en
Priority to GB51814/65A priority patent/GB1126673A/en
Priority to DE19651660216 priority patent/DE1660216B1/de
Priority to FR46793A priority patent/FR1467312A/fr
Priority to BE674986D priority patent/BE674986A/xx
Priority to CH72066A priority patent/CH441607A/fr
Priority to ES0322402A priority patent/ES322402A1/es
Application granted granted Critical
Publication of US3304593A publication Critical patent/US3304593A/en
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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

Definitions

  • This invention relates to an improved process and apparatus for bulking and/or texturing synthetic yarn, and more particularly relates to a method and apparatus for producing crimps in each filament of a continuous running strand by applying mechanical shock to the fibers as they pass over a vibrating head at a high linear rate.
  • a first process teaches the idea of subjecting the yarn to air jets which cause the filaments within the yarn to be blown apart and to become mutually entwined so that a certain amount of crimping or kinking occurs.
  • a sec-0nd process known as the false-twist process subjects linear increments of the yarn to torsional twisting about the yarns longitudinal axis, and the process further employs subsequent heating of the twisted yarn so as to substantially set the twist.
  • a third process includes the steps of passing the yarn over a heating element to raise its temperature to a point where the yarn becomes plastic but short of its melting point; and then stuffing the yarn into a stuffing box or else drawing the yarn over an acute-angle knife edge so as to distort its normal cross-sectional distribution of plastic, whereby when the yarn cools each filament will have a tendency to form a series of loops somewhat resembling the convolutions of a coil spring.
  • a fourth process has been suggested wherein the yarn is passed between electrodes to which a difference of potential is periodically applied at a relatively high repetition rate, the yarn having been heat-softened when it is introduced between the electrodes to permit it to distort under the potential stresses,
  • the present invention represents a novel approach employing the application of physical shock to the yarn as it is drawn over a crimping head which is vibrated at a relatively high mechanical rate, driven for instance by a signal recurring at at least a sonic rate, which signal is applied to a crystal transducer mechanically connected to the head.
  • yarn ends are drawn over the edges of crimping heads which are vibrated in such a direction as to pulse the yarn transversely of its linear axis, thereby distorting each of the fibers by relatively violent mechanical shock so that the fibers develop adjacent cusps or kinks, the separation between which depends upon the vibration rate of the head and the linear rate of travel of the yarn thereover.
  • the acceleration is of the order of magnitude of 1000 to 150,000 Gs, but the amplitude of the mechanical shock is only a few thousandths of an inch, perhaps 3 to thousandths.
  • Another object of the invention is to provide a bulking method and apparatus in which the yarn, while passing over the crimping head, changes direction at right angles or at obtuse angles so that the molecules in the fiber are transversely shocked at spaced points along their lengths.
  • the head comprises a small block against which the yarn is distorted by feeding the yarn up one side of the block, across the top of the block, and down the other side of the block with the block vibrating back and forth in a direction parallel to its sides.
  • the block is supported upon a crystal transducer which is connected to a signal generator capable of driving the transducer with a power oscillation, in the present embodiment of up to watts, at an ultrasonic rate of about 20 kilocycles.
  • the closeness together of the kinks in the filaments depends on the linear rate of movement of the yarn over the crimping head and upon the rate of vibration of the crystal transducer.
  • the displacements during vibration of the transducer affects the tightness or looseness of the kinks in the filaments, although once a sufiicient amplitude of displacement is reached to provide optimum kinking, further increase in amplitude does not appear to be beneficial and in some instances has even proven harmful.
  • the yarn will be free to vibrate in a standing wave mode having an amplitude which is much greater than the displacement of the head itself, and it appears that this standing wave vibration assists the crimping action by adding a jerking motion to the yarn at the same rate of occurrence as the vibrations of the head, and the amplitude of the standing wave being augmented greatly by resonance.
  • Experiments have also been run on the idea of placing a follower member opposite the head member itself so that the yarn passes between the two members. Because of the tremendous accelerations and low amplitudes involved, the follower member does not seem to touch the main vibrating head, but there appears tobe a pulsating cushion of air trapped between the heads.
  • the mechanism by which the presence of the follower mass helps the crimping action appears to be different from the resonance theory of the standing waves, perhaps based upon periodic clamping of the yarn to the main vibrating head so as to reduce the ability of the yarn to retreat as the vibrating head approaches its maximum advance against the yarn.
  • the distance of the drag means and of the pinch rolls from the top surface of the head is a function of the longitudinal stretch characteristics of the yarn as determined by its denier and by its composition, and that by moving the pinch rolls and the drag means further from the top surface of the head, too much stretch of the fibers may be permitted, such stretch allowing them to retreat from the advance of the head to such an extent that optimum crimping does not occur.
  • the crimping which takes place as a result of the ultrasonic vibration is permanent to a large degree, but the ultimate degree of the crimp can be increased by briefly heating the bulked yarn in untensioned condition after it leaves the pinch roll and before it is stored on a spindle. It is therefore desirable to provide a small heater through which the yarn passes in relaxed condition on its way from the pinch rolls to the storage spool.
  • One advantage of the present invention is that a very versatile bulking method is provided by which novel effects can be obtained.
  • a yarn can be provided having alternate bulked and non-bulked longitudinal portions by keying the crystal transducer on and off.
  • the extent to which the yarn is bulked is proportional to the extent to which the yarn is foreshortened. If, for example, a three foot length of yarn is subjected to the present process, it may be shortened to about one foot of bulked length. However, by grasping the ends of the one-foot length and pulling it out until it appears unkinked again, it will be found that the yarn under the latter circumstance is still approximately three feet in length. It thus appears that the present process does not stretch the fibers, it mere provides them with a sawtooth shape amounting to a permanent set to which the fibers return when longitudinal tension is released.
  • the benefits realized by the present apparatus and method include a reduction in size and a greater simplification in the mechanical complexity of the apparatus required to perform the present process.
  • a transducer-driving generator is required, such electronic equipment needs very little maintenance, and therefore is believed to be an improvement over the mechanical apparatus performing other texturizing or bulking processes.
  • the present system produces tighter and more uniform kinks in the filaments, and these kinks being closer together, the invention provides a finer ultimate texture having smaller tighter coils which when woven in a stretch material will permit the material to stretch and/or relax more smoothly.
  • the present process is anon-torque process of the general type referred to in Patents 2,919,653, 2,931,089, 3,028,653 and 3,028,654, as distinguished from a high-torque process such as the one mentioned above and shown in Patent 3,108,430 in which the yarn is twisted about its longitudinal axis.
  • the present type of nontorque yarn is believed to be more satisfactory since there is no tendency for it to twist while being woven or knitted, and since there is no tendency for the present yarn to distort a fabric due to strand rotation.
  • FIG. 1 is a diagrammatic view showing yarn passing from a spindle over a crimping head, and to a storage spool, and showing a diagram of suitable electrical wiring;
  • FIG. 2 is a perspective view showing multiple strands or ends of yarn being simultaneously bulked by the same head
  • FIG. 3 is an elevation view of a modified form of crimping head showing the yarn passing thereover and developing standing waves across the upper surface of the head;
  • FIG. 4 shows a second modification of the head, and illustrates how a different mode of standing waves can be set up where the head is vibrated at a different frequency
  • FIG. 5 shows a third modified form of the head having a serpentine upper surface located opposite a spring loaded follower member whose lower surface is shaped in the form of a substantially complementary serpentine contour
  • FIG. 6 is a greatly magnified view of a length of yarn in which the fibers are bulked in one longitudinal portion, and unbulked in adjacent portions.
  • FIG. 1 shows a practical illustrative embodiment using an ultrasonic generator 1 capable of delivering ultrasonic undulating electrical output at a high power level, the generator being connected to drive a crystal transducer 2 which supports and drives a mechanical motion transforming column 3 which in turn supports a crimping head 4 in the form of a rectangular block of metal, which can also be seen at 4 in FIG. 2.
  • the generator 1, the crystal transducer 2, and the support column 3 are purchased items manufactured by Branson Instruments, Model LS-75.
  • the electrical circuit of FIG. 1 also includes a rotary drum switch 5 which is capable of alternately making and breaking the circuit between the generator 1 and the transducer 2 when the drum 5 is rotated by a motor 6, thereby modulating the amplitude of the head vibrations at a rate which is slow as compared with the greater-thansonic vibration rate.
  • the drum 5 may also be considered as comprising an ON-OFF switch when it is manually positioned to either continuously make or break the circuit. It is also to be understood that the drum 5 can be replaced with other modulating means which would operate to increase and decrease the vibration amplitude rather than to key it ion, ifl'7,
  • the yarn Y to be processed is taken from one or more spindles 10 through guide means 11 and through friction drag blocks 12 and 13, the block 13 being supported on a rod 13a which can be reciprocated through a sleeve 14, and which is urged toward the block 12 by a spring 15 calibrated to provide a predetermined drag upon the yarn Y.
  • the yarn passes between the blocks 12 and 13 upwardly over the top surface of the crimping head 4 and down again on the other side of the head. It then passes between pinch rollers 16 and 17, the latter roller being driven continuously by a motor 18 and serving to draw the yarn over the crimping head 4 against the degree of tension determined by the spring 15.
  • the bulked yarn B passes over a roller 20 and downwardly to a storage spool 21 which is rotated by suitable means (not shown).
  • suitable means not shown.
  • the crimping of the filaments is permanent and that no further treatment of the yarn is necessary.
  • some improvement in the degree of bulking can be bad if the yarn which has been crimped is relieved of tension and then heat-treated somewhat, for example by passing it through an electricheater 22 which can be conveniently connected to a source of power.
  • PEG. 2 shows a modification of FIG. 1 in which multiple ends of yarn are passed over the same crimping head 4- so that they are simultaneously bulked, this being especially advantageous for production purposes, it merely being necessary to lengthen the friction blocks 12 and 13' as well as the pinch rolls l6 and 17' to accommodate plural strands.
  • the present thinking suggests that approximately 40 strands can be drawn over a single crimping head and that the electrical power to drive such a head would be about 75 watts.
  • the crimping heads are driven so that they reciprocate in the direction of the arrows A, and the yarn passes over the tops of the heads at a predetermined velocity in the direction of the arrows V. This velocity and the rate of vibration of the head are interrelated parameters which together determine how far apart the kinks will be separated in the bulked yarn.
  • the head shown in FIG. 3 comprises a block 24 having two recessed areas extending across the block for its full width in a direction measured normal to the plane of the paper on which the drawing is made. These recesses are separated by a cusp 25 in the center which would be located at a node in the vibratory pattern of the standing waves Y so that the vibration is essentially a full-wave mode.
  • a different mode of vibration is obtained in FIG. 4 by the head 25 which has only a single recess across its full width intended to permit a standing wave Y" to occur, resonance being obtained in FIG. 4 at a different frequency of the vibration head 26, as compared with the resonant frequency in FIG. 3, assuming the same weight of yarn.
  • FIG. 5 shows still another modified form of the head in which a head block 27 has a serpentine upper surface 27a extending the full width of the head, and a complementary follower block member 28 is mounted on a vertical rod 29 passing through a sleeve 30.
  • a spring 31 biases the follower member 28 downwardly toward the head member 27.
  • FIG. 6 shows a greatly magnified strand of yarn in which the yarn is alternately bulked and unbulked in a novel fashion.
  • This alternate bulking of the yarn is the result of rotation of the drum switch 5 by the motor 6 so that the energy to the crystal from the ultrasonic generator is alternately keyed on and off while the yarn is continuously drawn over the bulking head.
  • the method of bulking a synthetic yarn by crimping comprising (a) continuously passing the yarn over a crimping edge while tensioning the yarn on both sides of the edge to pull it thereagainst;
  • said head comprising at least tWo mutually spaced edges across which the yarn is passed under tension, and the head being recessed between the edges to provide clearance permitting the yarn to sustain standing waves therebetween.
  • said head comprising a block having a surface across which the yarn is passed under tension, a second block having a surface substantially complementary in shape to said surface of the head, and spring means urging the second block theretoward to press the yarn thereagainst.
  • said complementary surfaces being serpentine as viewed across the path of the yarn.
  • Apparatus for bulking a yarn of synthetic fibers comprising (a) a source of supply of said yarn;
  • transducer means coupled to the head for vibrating it in a direction to alternately increase and decrease the yarn tension
  • said drive roll means and said drag means being located close to the crimping head to reduce the tendency of the yarn to stretch between the head and these means to partially escape the shock of the applied vibrations.
  • said head comprising at least two mutually spaced edges across which the yarn is passed under tension, and the head being recessed between the edges to provide clearance permitting the yarn to sustain standing waves therebetween.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Treatment Of Fiber Materials (AREA)
  • Preliminary Treatment Of Fibers (AREA)
US427021A 1965-01-21 1965-01-21 Yarn bulking method and apparatus Expired - Lifetime US3304593A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US427021A US3304593A (en) 1965-01-21 1965-01-21 Yarn bulking method and apparatus
GB51814/65A GB1126673A (en) 1965-01-21 1965-12-07 Yarn bulking method and apparatus
DE19651660216 DE1660216B1 (de) 1965-01-21 1965-12-16 Vorrichtung zum Kraeuseln synthetischer Faeden
FR46793A FR1467312A (fr) 1965-01-21 1966-01-06 Procédé et appareil pour le crêpage des fils textiles
BE674986D BE674986A (OSRAM) 1965-01-21 1966-01-12
CH72066A CH441607A (fr) 1965-01-21 1966-01-19 Procédé et appareil pour le crêpage de fibres synthétiques
ES0322402A ES322402A1 (es) 1965-01-21 1966-01-21 Aparato para tratar fibras sinteticas.

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Application Number Priority Date Filing Date Title
US427021A US3304593A (en) 1965-01-21 1965-01-21 Yarn bulking method and apparatus

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US3304593A true US3304593A (en) 1967-02-21

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US427021A Expired - Lifetime US3304593A (en) 1965-01-21 1965-01-21 Yarn bulking method and apparatus

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US (1) US3304593A (OSRAM)
BE (1) BE674986A (OSRAM)
CH (1) CH441607A (OSRAM)
DE (1) DE1660216B1 (OSRAM)
ES (1) ES322402A1 (OSRAM)
FR (1) FR1467312A (OSRAM)
GB (1) GB1126673A (OSRAM)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3346932A (en) * 1965-09-07 1967-10-17 Monsanto Co Methods for relaxing synthetic fiber filaments
US3377673A (en) * 1965-12-27 1968-04-16 Phillips Petroleum Co Method and apparatus for crimping filaments
US3438104A (en) * 1966-02-25 1969-04-15 Phillips Petroleum Co Filament crimping method
US3439392A (en) * 1965-10-08 1969-04-22 Stevens & Co Inc J P Method and apparatus for texturizing synthetic thermoplastic yarns
US3514824A (en) * 1967-04-17 1970-06-02 Ici Ltd A method of producing a coherent multifilament yarn
US3534453A (en) * 1967-03-23 1970-10-20 Michel Serge Maxime Lefebvre Process for converting textile threads
US3548469A (en) * 1967-11-16 1970-12-22 Bayer Ag Method of and an apparatus for crimping synthetic yarns
US3640063A (en) * 1968-09-13 1972-02-08 Basf Ag Process and apparatus for crimping yarns and the like
US3646744A (en) * 1969-12-22 1972-03-07 Us Agriculture Method and apparatus for bulking yarn
US3672012A (en) * 1970-07-30 1972-06-27 Glenn A Burklund Apparatus for texturizing yarns and the like
US3704485A (en) * 1970-12-14 1972-12-05 Hercules Inc Apparatus for spreading a graphite fiber tow into a ribbon of graphite filaments
US3729914A (en) * 1971-06-08 1973-05-01 C Mcclure Strand treatment
US3745618A (en) * 1970-07-30 1973-07-17 G Burklund Methods for texturizing yarns and the like
US3966519A (en) * 1974-12-27 1976-06-29 Kimberly-Clark Corporation Method of bonding fibrous webs and resulting products
US4109353A (en) * 1974-12-27 1978-08-29 Kimberly-Clark Corporation Apparatus for forming nonwoven web
US4729151A (en) * 1986-09-10 1988-03-08 Rhs Industries, Inc. Apparatus for entangling yarn
US5102690A (en) * 1990-02-26 1992-04-07 Board Of Trustees Operating Michigan State University Method coating fibers with particles by fluidization in a gas
US5123373A (en) * 1990-02-26 1992-06-23 Board Of Trustees Operating Michigan State University Method for fiber coating with particles

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977661A (en) * 1955-11-18 1961-04-04 Deering Milliken Res Corp Yarn elasticizing apparatus
US3047932A (en) * 1959-08-18 1962-08-07 Deering Milliken Res Corp Apparatus for intermittently edgecrimping yarn
FR1342601A (fr) * 1962-12-28 1963-11-08 Application des ultra-sons au finissage des produits textiles artificiels ou synthétiques
US3167847A (en) * 1961-11-28 1965-02-02 American Enka Corp Treatment of multi-filament yarn

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD28546A (OSRAM) *
DE894433C (de) * 1938-08-19 1953-10-26 Siemens Ag Verfahren zur Herstellung von wollartigen kuenstlichen Faeden
DE1176311B (de) * 1955-11-02 1964-08-20 Deering Milliken Res Corp Verfahren zum Herstellen gekraeuselter Faeden oder Fadenbuendel aus synthetischen, thermo-plastischen, linearen Kondensationspolymeren
US2943377A (en) * 1959-06-29 1960-07-05 Elwood Res Company Method and apparatus for crimping filaments
US3052009A (en) * 1960-07-11 1962-09-04 Colorspace Patent Associates Apparatus for the crimping of synthetic fibers by electrostatic means

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2977661A (en) * 1955-11-18 1961-04-04 Deering Milliken Res Corp Yarn elasticizing apparatus
US3047932A (en) * 1959-08-18 1962-08-07 Deering Milliken Res Corp Apparatus for intermittently edgecrimping yarn
US3167847A (en) * 1961-11-28 1965-02-02 American Enka Corp Treatment of multi-filament yarn
FR1342601A (fr) * 1962-12-28 1963-11-08 Application des ultra-sons au finissage des produits textiles artificiels ou synthétiques

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3346932A (en) * 1965-09-07 1967-10-17 Monsanto Co Methods for relaxing synthetic fiber filaments
US3439392A (en) * 1965-10-08 1969-04-22 Stevens & Co Inc J P Method and apparatus for texturizing synthetic thermoplastic yarns
US3377673A (en) * 1965-12-27 1968-04-16 Phillips Petroleum Co Method and apparatus for crimping filaments
US3438104A (en) * 1966-02-25 1969-04-15 Phillips Petroleum Co Filament crimping method
US3534453A (en) * 1967-03-23 1970-10-20 Michel Serge Maxime Lefebvre Process for converting textile threads
US3514824A (en) * 1967-04-17 1970-06-02 Ici Ltd A method of producing a coherent multifilament yarn
US3548469A (en) * 1967-11-16 1970-12-22 Bayer Ag Method of and an apparatus for crimping synthetic yarns
US3640063A (en) * 1968-09-13 1972-02-08 Basf Ag Process and apparatus for crimping yarns and the like
US3646744A (en) * 1969-12-22 1972-03-07 Us Agriculture Method and apparatus for bulking yarn
US3672012A (en) * 1970-07-30 1972-06-27 Glenn A Burklund Apparatus for texturizing yarns and the like
US3745618A (en) * 1970-07-30 1973-07-17 G Burklund Methods for texturizing yarns and the like
US3704485A (en) * 1970-12-14 1972-12-05 Hercules Inc Apparatus for spreading a graphite fiber tow into a ribbon of graphite filaments
US3729914A (en) * 1971-06-08 1973-05-01 C Mcclure Strand treatment
US3966519A (en) * 1974-12-27 1976-06-29 Kimberly-Clark Corporation Method of bonding fibrous webs and resulting products
US4109353A (en) * 1974-12-27 1978-08-29 Kimberly-Clark Corporation Apparatus for forming nonwoven web
US4729151A (en) * 1986-09-10 1988-03-08 Rhs Industries, Inc. Apparatus for entangling yarn
US5102690A (en) * 1990-02-26 1992-04-07 Board Of Trustees Operating Michigan State University Method coating fibers with particles by fluidization in a gas
US5123373A (en) * 1990-02-26 1992-06-23 Board Of Trustees Operating Michigan State University Method for fiber coating with particles

Also Published As

Publication number Publication date
CH441607A (fr) 1967-08-15
FR1467312A (fr) 1967-01-27
ES322402A1 (es) 1967-03-16
DE1660216B1 (de) 1972-05-31
BE674986A (OSRAM) 1966-05-03
GB1126673A (en) 1968-09-11

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