US3609835A - Method and apparatus for texturizing yarn - Google Patents

Method and apparatus for texturizing yarn Download PDF

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Publication number
US3609835A
US3609835A US844054A US3609835DA US3609835A US 3609835 A US3609835 A US 3609835A US 844054 A US844054 A US 844054A US 3609835D A US3609835D A US 3609835DA US 3609835 A US3609835 A US 3609835A
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yarn
tension
jet
frequency
fluctuations
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US844054A
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English (en)
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Edmund F Boon
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Glanzstoff AG
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Glanzstoff AG
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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
    • D02G1/16—Producing crimped or curled fibres, filaments, yarns, or threads, giving them latent characteristics using jets or streams of turbulent gases, e.g. air, steam

Definitions

  • apparatus for producing a texturized, tangled or intertwined effect in the individual filaments of multifilament yarns.
  • apparatus which provides a bore, groove or the like as a yarn guide along whose longitudinal axis the yarn travels.
  • a jet of a fluid medium under pressure is blown onto it from one or more nozzles, with the result that the individual filaments are irregularly looped and/r intertwined.
  • the nozzles may be differently arranged in various positions.
  • the yarn or multifilament thread is guided through the jet under a tension which prevents it from slackening.
  • a measure of the texturization of the yarn i.e. the amount of interlacing or entanglement, is the so-called gap length, sometimes referred to as the opening length.
  • This gap length is defined as the distance by which a needle or pin inserted into the yarn perpendicularly to or radially of the yarn axis can be displaced axially of the yarn until the next entanglement or point of interlacing prevents further relative movement between the needle and the yarn. It will be apparent that the shorter the gap length, the greater the extent to which the individual filaments are entangled in the yarn.
  • One object of the present invention is to make it possible to texturize multifilament yarns of widely variable denier in such a Way that the intervals between the entanglements or points of interlacing, i.e. the gap lengths, are kept the same or made to differ under predetermined and controlled conditions throughout the entire winding operation, i.e. in a manner comparable to the controlled conditions of producing a twisted yarn. It is also an object of the invention to provide a method or means to preadjust both the average gap length and to control any deviation from this average gap length to a large extent.
  • the invention is preferably carried out in combination with a yarn texturizing apparatus identical with or similar to that described in Canadian patent specification No. 554,150.
  • the apparatus of this invention is readily adapted for use with conventional jet texturizing equipment.
  • the present invention essentially provides a method for producing a texturized multifilament yarn of predetermined average gap length, as defined hereinabove, in which the yarn to be treated is passed through a jet of a fluid medium, preferably air or steam, which is directed substantial- 1y perpendicularly to the linear path of travel of the yarn and thereafter flowing away or passing off freely from the texturizing zone, i.e. where the jet intersects the yarn path, and in which the yarn is simultaneous subjected to fluctuations in its linear tension as it passes through the texturizing zone, the frequency of the fluctuations in tension being given by the equation ice W 1 11- mm.
  • a fluid medium preferably air or steam
  • the yarn In addition to a well defined maximum occurrence of the desired value calculated for the gap length, the yarn also exhibits nodules with lengths of up to a few centimeters. A distribution such as this is essentially obtained in those cases where W/n or W-t is less than about 0.02 meter. In addition, a distribution of gap lengths of this kind is obtained in those cases where the lower yarn tension in particular is reduced to approximately zero.
  • the third possibility represents the preferred embodiment of the present invention wherein it is possible to obtain the expected or calculated gap length in the treated yarn with high accuracy and a high frequency of distribution or, where irregularity is required, to obtain a specific irregularity as between two or more calculated gap lengths with a high degree of accuracy.
  • Blowing or initial jet pressures of from 2.5 to 5 atms., preferably from 3.2 to 4.2 atms., are employed in those cases where air is used as the fluid jet medium.
  • the initial pressures are corrected in a manner known to any competent expert in order to achieve the jet velocities as governed both by material and physical data to guarantee approximately equivalent jet impulses. The same applies as regards nozzles differing in form from those described.
  • air as the fluid jet medium at approximately room temperature, e.g. at approximately 20 C., within the abovenoted pressure range.
  • the velocity of the jet as it leaves a nozzle furnished with a cylindrical bore or duct to impinge on the yarn amounts to the so-called critical velocity, e.g. about 315 meters/ second.
  • critical velocity e.g. about 315 meters/ second.
  • the yarn tension preferably fluctuates between a lower range of from 0.02 to 0.18 gram/denier and an upper range of from 0.4 to 0.8 gram/ denier so as to achieve a narrow range of distribution of gap length close to the calculated value.
  • the lower tension range is preferably between 0.04 and 0.15 gram/denier and the upper range preferably between 0.45 and 0.63 gram/denier.
  • favorable values for the frequency of the fluctuations in yarn tension lie at least above about 1500 cycles per minute, e.g. between about 2000 cycles/ min. and about 10,000 cycles/ min. and preferably between about 5,000 cycles/min. and about 8,500 cycles/min, i.e. corresponding to values between about 33 c.p.s. and about c.p.s., and preferably between about 83 c.p.s. and about 142 c.p.s.
  • important factors in the process of the invention include the take-off rate or speed of yarn travel, the frequency of the applied fluctuation in yarn tension, the upper and lower tension ranges, the nozzle dimensions and the initial jet pressure or the jet velocity and pressure at the mouth of the nozzle.
  • the ratio between minimum and maximum yarn tension and also the average value of the two tension ranges must be kept within relatively narrow limits. In this case it is essential to maintain a minimum tension, especially with a lower limit, as well as a maximum tension limited at both ends of the prescribed range, these tensions being dependent upon the denier of the yarn.
  • Another major advantage of the method according to the invention is that it is possible to obtain a texturized yarn which, unlike conventional yarns, has a regular distribution of nodules comparable to the regularity of a twisted yarn.
  • the calculated gap length is closely approximated throughout the entire texturizing treatment and can be adjusted as desired to provide a highly uniform degree of texturization.
  • EXAMPLE 1 A polyester yarn having a yarn size of 68/24 denier was treated in a jet texturizing apparatus as described in Canadian patent specification No. 554,150 and indicated in FIG. 3 of the drawings with the following dimensions:
  • a pin is arranged 30 cm. in front of the blowing unit between two yarn guides arranged 15 cm. apart the pin being eccentrieally mounted with respect to the line of yarn travel on a disc rotatable about an axis perpendicularly to the direction of yarn travel, e.g. as indicated in FIG. 2 of the drawings.
  • the pin serves to deflect the yarn periodically.
  • the eccentric pin was arranged in such a way that the minimum yarn tension obtained was about 0.12 gram/denier and the maximum yarn tension obtained was about 0.52 ram/denier.
  • the frequency of the fluctuation in yarn tension between these minimum and maximum values was adjusted to 7000 cycles/min. and the rate of yarn travel was 245 meters/min.
  • the gap length was highly regular at 3.5 cm. which corresponds exactly to the calculated value:
  • EXAMPLE 2 In an arrangement of exactly the same kind as that of Example 1, an eccentric is driven through an interference gear or so-called variable speed gearing means so as to produce deviations of 115% at an average frequency of 7000 cycles/ min. Examination of the gap lengths revealed an average gap length of 3.5 cm. with fluctuations in size corresponding to the percentage deviations in the deflection of tension frequency from the average value of 7,000 cycles/min. This example clearly shows that the method of the invention permits a very excellent control over the size of the gap lengths so as to be able to achieve practically any desired distribution of various gap lengths with uniform and reproducible results.
  • Example 5 The conditions of Example 3 were modified by increasing the upper yarn tension in stages. It was found that when the maximum yarn tension was increased beyond 0.59-0.60 gram/denier and the lower yarn tension was simultaneously lowered to below .074 gram/denier, neither a regular distribution of the gap lengths nor one changing with the tension frequency occurred in a well defined form. At a blowing pressure of from 3.5 to about 3.7 atm., there was a wider variation in the gap lengths with a maximum occurrence at around 3.5 cm. i.e. corresponding to procedure (a) above. At a blowing pressure of from about 3.7 to 3.9 atms., there was a pronounced peak at a gap length of 3.5 cm. although very short as well as relatively long Opening lengths were also noticed, i.e. corresponding to procedure (b) above.
  • FIG. 1 illustrates different distribution curves for the opening or gap length depending upon the particular technique or procedure used, the frequency of occurrence of each particular gap length being plotted against the gap length;
  • FIG. 2 is a schematic illustration of a combination of apparatus for carrying out the process according to the invention
  • FIG. 3 illustrates in partly schematic form a known type of jet nozzle and resonance chamber suitable for carrying out the process according to the invention
  • FIG. 4 is a partly schematic perspective view of an electromagnetic yarn brake suitable for achieving a fluctuating yarn tension
  • FIG. 5 is a schematic representation of drive means linked with an eccentric deflecting cam by means of a variable gearing means to produce specific deviations from an average frequency of fluctuation in tension.
  • the curve 1 shows the frequency distribution of the gap lengths in the treatment of a yarn in following procedure (a) above.
  • Curve 2 shows the distribution of the gap lengths in the case of a yarn treated in accordance with the preferred embodiment of the invention, i.e. case (c) above.
  • Curve 3 shows the frequency distribution of the gap lengths formed in cases where the procedure resulted in case (b).
  • FIG. 2 schematically illustrates the more important elements of an apparatus for carrying out the process according to the invention.
  • a multifilament yarn 4 being texturized passes through the yarn guides 5 and 6 which are disposed respectively in front of and behind an eccentric disc 7 which carries a deflector pin 8.
  • the nozzle 9 is of open design with a suitable embodiment thereof being shown by way of example in FIG. 3.
  • yarn guides 10 and 11 Arranged respectively in front of and behind the jet or texturizing zone, there are placed yarn guides 10 and 11 by which the yarn is held in a normally linear path through the jet. How'- ever, it will be recognized that the yarn tends to fluctuate from side to side under the influence of the jet, particularly with a resonance chamber aligned on the same axis with the jet nozzle.
  • Any form of blowing unit can be used which enables the fluid medium to flow off relatively freely from the texturizing zone.
  • the yarn 4 travels from a delivery means such as a pair of nip rolls 12 and 13 arranged in front of the yarn guide 5, through the yarn guide 5, and over the deflector pin 8 as an eccentric yarn contacting element or over the circumferential yarn contacting surface of the disc 7.
  • a delivery means such as a pair of nip rolls 12 and 13 arranged in front of the yarn guide 5, through the yarn guide 5, and over the deflector pin 8 as an eccentric yarn contacting element or over the circumferential yarn contacting surface of the disc 7.
  • a variation in yarn tension is thus produced as between the deflector pin 8 and the disc 7 as the yarn passes through the yarn guide 6 of the blowing nozzle 9 and then through another delivery means such as rolls 14 and 15 to a conventional winding or take-up mechanism (not shown).
  • the axis of rotation of the eccentric disc 7 is preferably arranged in such a way that it can be displaced perpendicularly of the direction of yarn travel, the axis remaining parallel to its original position. In this way the extent to which the yarn is deflected can be controlled.
  • the pin 8 on the disc 7 may also be radially adjustable, or pins of different sizes can be used. It will be evident that one yarn tension fluctuation cycle or period corresponds to one revolution of the eccentric disc 7 when using a single deflector pin 8. Instead of one pin 8, two or more pins 8' may be arranged at regular intervals around the periphery of the eccentric disc, i.e. as indicated in dotted lines. The upper limit to the number of pins is governed by the requirement that no pin 8' must touch the yarn until the preceding pin has ceased to be in contact with the yarn.
  • any other known adjustable tensioning means may be used or adapted to produce the fluctuations in yarn tension.
  • an electromagnetic yarn brake as illustrated in FIG. 4 which can be rapidly switched on and off to produce the required frequency, is also especially suitable in providing a smooth transition back and forth between the upper and lower values of tension.
  • a vibrator of adjustable frequency may also be used. It is not essential for the fluctuations in yarn tension to provide a sine Wave or curve when plotting the amount of tension against time, and in fact, it is preferable to maintain the lower tension on the yarn over a large proportion of each cycle with only a relatively brief interruption during which the tension is quickly increased to the prescribed higher tension.
  • FIG. 3 is an exemplary form of a suitable jet nozzle which has a nozzle body 16 with a jet channel or blowing duct 17 and, opposite this duct, a second body 18 in which a resonance or compression chamber 19 is arranged.
  • a texturizing zone is defined by the common axis of the blowing duct 17 and the compression chamber 19.
  • Two yarn guides and 11, each of which is preferably in the form of a narrow eye or small tube, are arranged just in front of and just behind the texturizing zone in such a way that they tend to keep the yarn 4 passing precisely through the jet of air or other fluid medium.
  • the jet nozzles that may be used for carry ing out the process according to the present invention are by no means limited to this particular embodiment as shown in FIG. 3.
  • the resonance or compression chamber 19 may be omitted entirely or may be replaced by a flat plate or any other type of obstacle to the jet flow.
  • the only requirement that must be satisfied is that the fluid medium should be able to flow off relatively freely from the treatment zone, preferably not at all or only partly in the direction of the general yarn axis.
  • the types of jet nozzles or blowing nn its having this characteristic freedom of flow are referred to in the present context as nozzles of open design.
  • the jet impinge substantially or at least approximately perpendicularly to the yarn axis, but it is also permitted to dissipate as freely as possible away from the point of treatment or from the resonance zone established by means of an oppositely disposed resonance chamber. Poorer results are achieved if this dissipation of the jet stream is channeled in a specific direction, especially if directed solely along the axis of the yarn.
  • the means used to generate the fluctuations in yarn tension must be arranged between the delivery means 12, 13 and 14, but may be disposed on either side of the nozzle 9.
  • the yarn tensioning means may be arranged in front of or behind the nozzle 9, as seen in the direction of yarn travel.
  • the eccentric disc 7 of FIG. 2 can be driven by a variable speed motor 23 to establish a specific desired frequency of fluctuation in yarn tension while arranging a variable speed gearing means 24 between the motor 23 and the disc 7 so as to produce a variation in the fluctuation frequency, e.g. both above and/or below the average or prefixed frequency established by the motor 23.
  • n is the number of cycles of the fluctuations in tension per minute
  • W is the rate of linear travel of the yarn in meters per minute
  • L is the required average gap length of the texturized yarn in meters.
  • a method as claimed in claim 3 wherein the air pressure for producing the jet is between about 3.2 and 4.2 atmospheres.
  • a method as claimed in claim 1 wherein the frequency of said fluctuations in yarn tension is from about 5,000 to 8,500 cycles per minute.
  • a method as claimed in claim 7 wherein the frequency of said fluctuations in yarn tension is from about 5,000 to 8,500 cycles per minute.
  • Apparatus for producing a texturized multifilament yarn having a predetermined average gap length which comprises in combination:
  • a texturizing jet nozzle of open design to direct a jet of fluid medium onto said multifilament yarn with means to guide said yarn in a normally linear path through said jet while the fluid medium passes off substantially freely from its point of directed jet contact with said yarn;
  • n is the number of cycles per minute of the fluctuations in yarn tension
  • W is the rate of linear travel of the yarn in meters per minute
  • L is the required average gap length in meters.
  • Apparatus as claimed in claim 11 wherein said texturizing jet nozzle is directed substantially perpendicularly to the linear path of the yarn and is so arranged together with said yarn guide means to permit the fluid medium to flow freely away from the zone of jet contact with the yarn in directions predominately other than the path of the yarn.
  • Apparatus as claimed in claim 11 wherein said texturizing jet nozzle is combined with a resonance cham- 10 her opposite to and on a common axis with said nozzle and adapted to receive said jet of fluid medium to create a turbulent texturizing zone therebetween.
  • Apparatus as claimed in claim 11 wherein two yarn conducting means are arranged on either side of said nozzle and said means for generating the fluctuations in yarn tension is arranged between one of said conducting means and said nozzle.
  • Apparatus as claimed in claim 14 wherein said means for generating the fluctuations in yarn tension is arranged between the first of said yarn conducting means and the nozzle as seen in the direction of yarn travel.
  • Apparatus as claimed in claim 11 wherein said means for generating the fluctuations in yarn tension is an electromagnetic yarn brake.
  • Apparatus as claimed in claim 11 wherein said means for generating the fluctuations in yarn tension is a yarn deflecting means including a rotatable eccentric driven by a variable speed motor.
  • Apparatus as claimed in claim. 11 including additional means to program variations in the frequency n of said yarn tension fluctuations in an amount of up to i-2S% of the average frequency established by said means for generating said fluctuations.
  • Apparatus as claimed in claim 11 including additional means to program variations in the frequency n of said yarn tension fluctuations in an amount of from about :5% up to about il5% of the average frequency established by said means for generating said fluctuations.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Textile Engineering (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Inorganic Fibers (AREA)
  • Preparation Of Compounds By Using Micro-Organisms (AREA)
  • Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
US844054A 1968-07-24 1969-07-23 Method and apparatus for texturizing yarn Expired - Lifetime US3609835A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19681760957 DE1760957A1 (de) 1968-07-24 1968-07-24 Verfahren zum Verwirbeln der Einzelfaeden multifiler Garne

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US3609835A true US3609835A (en) 1971-10-05

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US844054A Expired - Lifetime US3609835A (en) 1968-07-24 1969-07-23 Method and apparatus for texturizing yarn

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US (1) US3609835A (enrdf_load_stackoverflow)
JP (1) JPS4833422B1 (enrdf_load_stackoverflow)
AT (1) AT318792B (enrdf_load_stackoverflow)
BE (1) BE735829A (enrdf_load_stackoverflow)
CH (1) CH485884A (enrdf_load_stackoverflow)
DE (1) DE1760957A1 (enrdf_load_stackoverflow)
ES (2) ES369806A1 (enrdf_load_stackoverflow)
FI (1) FI49327C (enrdf_load_stackoverflow)
FR (1) FR2013625A1 (enrdf_load_stackoverflow)
GB (1) GB1232716A (enrdf_load_stackoverflow)
IL (1) IL32583A (enrdf_load_stackoverflow)
LU (1) LU59094A1 (enrdf_load_stackoverflow)
NL (1) NL6911292A (enrdf_load_stackoverflow)
NO (1) NO123096B (enrdf_load_stackoverflow)
RO (1) RO57729A (enrdf_load_stackoverflow)
SE (1) SE347033B (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2200390A1 (enrdf_load_stackoverflow) * 1972-09-14 1974-04-19 Mach Dev Enterprise
US4120078A (en) * 1975-12-24 1978-10-17 Basf Aktiengesellschaft Simultaneous texturizing and entangling of filament bundles
US4159619A (en) * 1976-09-13 1979-07-03 Akzona Incorporated Method for producing novelty yarns
US4184316A (en) * 1976-09-13 1980-01-22 Akzona Incorporated Production of novelty yarns
US4209881A (en) * 1978-03-21 1980-07-01 Phillips Petroleum Company Knitting intermittently drawn yarns
US4437301A (en) 1982-03-25 1984-03-20 Milliken Research Corporation Method of making yarn
US4467594A (en) * 1981-03-05 1984-08-28 Milliken Research Corporation Spun-like textured yarn
US5221059A (en) * 1991-01-30 1993-06-22 Basf Corporation Uniform yarn tensioning

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2200390A1 (enrdf_load_stackoverflow) * 1972-09-14 1974-04-19 Mach Dev Enterprise
US4120078A (en) * 1975-12-24 1978-10-17 Basf Aktiengesellschaft Simultaneous texturizing and entangling of filament bundles
US4159619A (en) * 1976-09-13 1979-07-03 Akzona Incorporated Method for producing novelty yarns
US4184316A (en) * 1976-09-13 1980-01-22 Akzona Incorporated Production of novelty yarns
US4209881A (en) * 1978-03-21 1980-07-01 Phillips Petroleum Company Knitting intermittently drawn yarns
US4467594A (en) * 1981-03-05 1984-08-28 Milliken Research Corporation Spun-like textured yarn
US4437301A (en) 1982-03-25 1984-03-20 Milliken Research Corporation Method of making yarn
US5221059A (en) * 1991-01-30 1993-06-22 Basf Corporation Uniform yarn tensioning

Also Published As

Publication number Publication date
SU380018A3 (enrdf_load_stackoverflow) 1973-04-20
RO57729A (enrdf_load_stackoverflow) 1974-12-15
NL6911292A (enrdf_load_stackoverflow) 1970-01-27
DE1760957A1 (de) 1971-12-30
LU59094A1 (enrdf_load_stackoverflow) 1969-11-21
SE347033B (enrdf_load_stackoverflow) 1972-07-24
ES369806A1 (es) 1971-12-16
AT318792B (de) 1974-11-11
BE735829A (enrdf_load_stackoverflow) 1969-12-16
IL32583A (en) 1972-07-26
GB1232716A (enrdf_load_stackoverflow) 1971-05-19
FI49327B (enrdf_load_stackoverflow) 1975-01-31
ES394225A1 (es) 1973-12-01
CH485884A (de) 1970-02-15
FR2013625A1 (enrdf_load_stackoverflow) 1970-04-03
IL32583A0 (en) 1969-09-25
JPS4833422B1 (enrdf_load_stackoverflow) 1973-10-13
NO123096B (enrdf_load_stackoverflow) 1971-09-27
FI49327C (fi) 1975-05-12

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