US3413697A - Apparatus for production of high-shrink yarn - Google Patents

Description

Dec. 3, 1968 A. H. AGETT ET 3,413,697

APPARATUS FOR PRODUCTION OF HIGH-SHRINK YARN 5 Sheets-Sheet 1 Original Filed March 26, 1962 cm: 9 q I l l N FEE n menu ,5: 5M5 FII| |I|L 3 mm w z 7 m Qzom m zmva EB "ill |1|L rlllll lw hwv m mv w mm H u J J r371. r571. r.L r171 So Tax 23 v 2E0 Tex w o in. @200 Fll lIlL rlllllvu 1|| P 11L N g 8 3 AW on S L ha 2% .25 A LWfiE 51 E55 mEQEmB 2am om 9 w. 2 9

Albert Henry Age MY/iam Lotus Aspy,J/:

INVENTORS BY Mu, HM! K 74 ATTORNEYS AND A6507 1968 A. H. AGETT ET AL 3,413,697

APPARATUS FOR PRODUCTION OF HIGH'SHRINK YARN Original Filed March 26. 1962 3 Sheets-Sheet 3 skw g Albert Henry Age/t William Lotus Aspy, Jr.

Dec. 3, 1968 -r1 ET AL 3,413,697

APPARATUS FOR PRODUCTION OF HIGH-SHRINK YARN 3 Sheets-Sheet 3 Original Filed March 26, 1962 Al bgrt Henry Age" WIIIIOII'I Loius Aspey,Jr. INVENTORS BY 7M ATTORNEYS 301 .E o hmm I 21:22am 20mm 30;.

United States Patent 3,413,697 APPARATUS FDR PRQDUCTION 0F HIGH-SHRTNK YARN Albert H. Agett and Wiiliain L. Aspy, Jr., Kingsport,

TemL, assignors to Eastman Kodak Company, Rochester, N.Y., a corporation of New Jersey Application Mar. 26, 1962, Ser. No. 182,500, now Patent No. 3,258,825, dated daily 5, 1966, which is a continuation-in-part of application Ser. No. 150,320, Nov. 6, 1961. Divided and this application Feb. 28, 1966, Ser. No. 559,012

2 Claims. (Cl. 28-1) ABSTRACT OF THE DISCLOSURE Apparatus arrangement including drafting rolls, bulking jet, crimper and heat setting equipment which in combination produce a continuous filament yarn having higher bulk and improved shrink properties.

This is a division of Ser. No. 182,500, filed Mar. 26, 1962, now U.S. Patent 3,258,825 granted July 5, 1966.

This invention relates to the production of high-shrink yarn. More particularly, this invention concerns an apparatus arrangement whereby continuous filament yarn is given an air-jet treatment for the increasing of the high bulk and high shrink properties as well as increasing the linear speed of production thereof.

In our application Ser. No. 150,320, filed Nov. 6, 1961, now abandoned, of which Ser. No. 182,500 is a continuation-in-part, we have disclosed a high-bulk and high-shrink yarn and method and apparatus for producing same. In said application we have disclosed the subjecting of yarn ends after drafting up to 850% to a jet treatment for imparting a certain amount of entanglement to the yarn. The yarn is preferably taken up from the jet at a speed approximately equal to or slightly lower than the speed at which it is introduced thereto. Although such a procedure satisfactorily fulfills the needs of high-bulk yarn producers, by the use of such a jet or gas treatment there is a possible tendency, unless close supervision and control of this specific operation is provided, for air treatment to reduce the amount of crimp recovery and high bulk retention and resilience which may be imparted to the yarn in accordance with the process which we have disclosed in said copending application. Also the yarn industry is always desirous of increasing speed of production. It is apparent, therefore, that the development of a new, more efficient jet treatment which would provide increased resilience and crimp retention represents a highly desirable result. After extending investigation we have found an apparatus arrangement for making highshrink, high-bulk yarn in which the speed of production as well as the capability of imparting a lasting crimp is additionally enhanced or secured.

This invention has for one object to provide an apparatus arrangement for increasing the crimp-retention or crimp-recovery produced by heat treatment in the production of high-shrink yarn. Another object is to provide an apparatus for increasing the cover and improving the hand of high-shrink, high-bulk yarn. A further object is to provide an apparatus arrangement for preventing or substantially eliminating the capability of high-shrink, high-bulk yarn to lose at least a part of its crimp. Another object is to provide a jet construction with facilities for controlling the degree of entanglement and degree of gas treatment of yarn subjected thereto. Still another object is to increase the bulkiness, resilience and springiness in continuous-filament yarn. Other objects will appear hereinafter.

In the broader aspects of our invention we have found that by subjecting tow to a special gas treatment which may be used alone or to supplement a separate crimping operation in the preparation of a high-bulk yarn, the tendency of the yarn to lose some of its crimp or resilience in further processing is minimized and the bulk is increased. The preferred gas treatment is provided by passing the yarn through a circular jet wherein it is subjected to a controlled gaseous expansion, preferably of compressed air, in a specially adapted venturi nozzle described in more detail hereinafter. The tow may be passed on to a crimping operation after being expelled from the jet under the influence of the expanding gas flow. In accordance with our invention the jet is preferably equipped at the exit portion of such a venturi nozzle with a plurality of flat spring members whereby the tow may be retarded or partially confined as it exits from said venturi. The tow may be passed to the jet treatment either as spun and preferably stretched or from tow packages.

For assistance in a better understanding of the present invention reference is made to the attached drawing forming a part of the instant application.

FIG. 1 is a flow diagram of a process such as may be carried out in accordance with the present invention.

FIG. 2 is a cross-sectional view of a circular jet such as may be used in carrying out the process of the present invention.

FIG. 3 is a side elevation view somewhat of a schematic nature illustrating the manner in which the straightening out of the tow is decreased and the crimp retention aided by retentive fingers affixed to a venturi nozzle portion of the jet of FIG. 2.

FIG. 4 is a schematic side elevation view of a jet without the retentive fingers shown in FIG. 3.

FIG. 5 is a schematic elevation of the combined tow treating apparatus of the present invention.

Reference is now made to FIG. 1. In the spinning operation 10, one or more spinning cabinets (not shown) of any usual dry spinning or melt spinning equipment construction may be used to produce a plurality of individual filaments of suitable denier and cross-sectional shape, for example 1.5-16 denier per filament and regular clover-section, Y or C yarn. More detailed descriptions of methods of spinning and spinning equipment which may be used in the process of this invention are found in our co-workers US. Patents 2,829,027, 2,750,653 and 3,000,053. Yarn ends produced by the spinning operation may be passed through lubricating zone 12 wherein an appropriate amount of lubricant is added prior to a drafting operation indicated at 14. Lubricant may be applied as described in our co-workers US. Patent 2,807,864. After drafting up to 850%, that is, stretching to a length of up to 8%. times their original length, preferably in accordance with an idler roll, preheat roll, first draft roll, second draft roll, third draft roll arrangement, described below in more detail, the yarn ends are subjected to a jet treatment at 16. The desired degree or controlled amount of entangling is imparted to the yarn by use of a gas jet such as shown in detail in FIG. 2 described hereinafter. The pressure may be regulated in such a way as to further assist in limiting the amount of entangling to the desired degree. The preferred speed of take-up of the jet-trained yarn is approximately equal to or slightly lower than the input speed. The yarn ends thus lubricated, drafted, and exposed to our controlled jet treatment may next be conducted into a crimping zone 18, preferably of a conventional stufier-box type or of the improved stutter-box construction also described below. If desired, the crimper 18 may be positioned prior to the gas jet 16. The crimped yarn is then subjected to drying and heat action in a heat-setting zone 20 to a high-bulk, high-shrink, high crimp-retention yarn product. The yarn may then be converted to cut-staple form and processed accordingly, packaged for movement to another point for further processing, or subjected to further processing in continuous filament form. If a cut-staple yarn is to be used in making a carpet, the yarn, as indicated in the drawing, is first cut into staple at 22, next carded at 24, then subjected to drawing at 26 and roving at 28 prior to plying at 30. When continuous filament yarn is used in forming a carpet the plying may be performed substantially direcly after the heat-setting step. When the yarn is cut into staple fiber, after carding at 24 it may be converted to non-woven fabric, as indicated at 32, using an appropriate bonding agent. For carpet use, after plying at 30 the yarn is formed on cones at 34 from which it may be tufted into carpet at 36 and then subjected to latexing and curing at 38. If it is desired to impart further shrinkage and crimp retention, it may be subjected to a further heat-treating step at 40. If it is desired to impart additional high bulk and characteristic retentive crimp to the yarn prior to converting it to a carpet or other appropriate product, it may be formed into skeins at 42 and then subjected to an appropriate heat treatment at 44.

Referring to FIG. 2, a shrouded circular jet such as we have found most effective in jet treating step 16 of FIG. 1 will now be described.

The jet 46 is composed of an outside shell 48 containing several inner members 50, 52 and 54 held in place by threaded plugs 56 and 58. A passageway 60 extends through the jet device so that the continuous multifilament tow may be passed from the entrance 62 in member 50 to an exit 64 in member 54. The passageway in member 50 is substantially of uniform diameter. The outer surface 66 of the lower end of member 50 is conical in shape with an included angle of about 40 to 80 degrees, for providing, in conjunction with the tapered surface 68 of thin plate orifice plate 52, an annular orifice or passageway for metering the air flow into the venturi tube member 54.

The venturi tube member 54 is provided with a converging entrance section 70 of about 30 to 40 degrees included angle, and in series a straight cylindrical tube passage 72 having a length of from 2 to 10 times the inside diameter of the passage 72, and a flaring or diverging exit section 74 with an included angle of from 2 to 7.

This exact construction of this portion of the jet assures a maximum controlled entangling effect on the tow. If this uniform passage 72 is too short, or the exit angle of passageway 74 is too great, less than optimum entangling and final yarn crimp-recovery and retention will result. Likewise, if passage 74 has little or no exit angle flare, the entangling of the tow will also be poor. Best results are obtained when the length of passageway 72 is about six times its inside diameter and the included angle of the exit passage 74 is about 3 to degrees.

In addition, for proper functioning of the jet, the inside diameter of passageway 72 is best at about 0.75" for a tow of about 37,000 denier size, and is best at about 163% of the diameter of the orifice plate orifice 68 and 400% of the inside diameter of the passageway 60 in inlet tube 50. The taper 66 of tube 50 is preferably about 60 degrees and about 30 degrees less than the angle of the taper of the orifice 68 in plate 52 which is preferably about 90 degrees. Proper sizing of these items insures that the jet 46 will produce a suction at entrance 62 to facilitate threading the tow into the jet 46. It also insures metering and impingement of the air onto the tow as it enters the orifice plate. The passageways in the jet should be in accurate concentric and axial alignment to insure uniform impingement of the air on the tow around the periphery of the tow and to insure a minimum of turbulence and swirling or twisting of the air flow. If the air flow swirls, it will tend to twist the tow rather entangling it and separating the filaments from each other.

Air is provided to the jet shell 48 through one or more openings 76 and 76' to an annular chamber formed by the outer surface of inlet member 50 and shell 48 and sealed at one end by threaded plug 56. It has been found that, while one inlet 76 is often adequate, better air flow distribution can be obtained with two or more openings equi-spaced around the shell periphery. The air from the chamber 78 then impinges on the tow by passing through the annular orifice formed by the tapered portion 66 of inlet tube 50 and the tapered opening 68 in orifice plate 52.

While the design and assembly of the jet have been described in a specific manner it will be recognized that variations in the size of the jet, the manner of assembling the component parts of the jet and variations in the shape of non-critical surfaces can be made without departing from the spirit of the invention.

Most effective crimp retention and high bulk was obtained when the venturi throat length to diameter ratio was about 6 to 1. The exit flare or diverging portion of the nozzle preferably has an included angle of about 3 to 5 degrees. It might also be pointed out that use of just a long straight tube with no divergent exit angle and no shrouded or restricted exit portion gives less controllable entangling as well as less satisfactory crimp retention in the final yarn product. This the venturi tube design is of some importance to obtain optimum results according to our invention.

It has been further found that the entangling of the tow can be materially enhanced if the flow of the tow as it exits from the jet venturi member 54 is retarded and partially confined. To achieve this end, a plurality of flat spring fingers 80, 80, 80" and others (not shown) are positioned equidistant around the outer surface of the venturi member 54 and extend beyond the end of the member 54, for example for a distance of 3" to 8" for the jet described hereinabove. The fingers 80 may be curved slightly outward, for example as at 82, to avoid snagging the tow, are slidable axially on the member 54, and are held in place by a clamp ring 84 and suitable thumb screw tightening means 86 or other appropriate fastening device. The force to spring the fingers outward is adjustable by moving the clamp 84 closer to or farther away from the end 64 of the member 54.

The effect of these fingers is to retard the exit of the tow from the jet and cause a temporary pile-up of a mass of disoriented filaments through which the exhaust air from the jet must pass.

Thus, as shown in FIG. 3, the filaments 88 exit from the confined zone 90 formed by fingers 80, 80', 80" of jet 46 in highly resilient crimped or crinkled form. The freshly spun filaments may have a certain amount of natural or inherent resiliency or crimp which the jet fingers will enhance and tend to prevent removal of in later processing steps. The resiliency and crimp retention of the filaments, whether previously or subsequently crimped or not, are improved and the tendency of further processing to straighten out the filaments or remove some of the resilience or crinkle therefrom substantially eliminated by passage through jet finger zone 90.

In FIG. 4, relatively straight but somewhat bulked or uncrinkled tow 92 is shown passing directly from the exit portion of an unfingered jet 46 without passing through a restricting or confining zone.

FIGURE 5 represents a preferred apparatus embodiment capable of producing the high-bulk yarn product of the invention in which the tow 118 is passed from spinning cabinets under an idler roll 120 for about /6 of its peripheral surface and then over and around a preheat roll 122, which may be heated by shoes or other conventional heating means (not shown). The tow should be in contact with the preheat roll 122 for at least 200 of a circular path. It then passes over and around a first draft roll 124 moving at about 1.6 times faster than preheat roll 122 in order to provide the necessary tension for an initial drafting or stretching step. Again the tow should be in contact with at least 200 of a circular path while in contact with said first draft roll 124. Additional tension is then applied as the tow moves over a second draft roll 126 and the tow is drawn or stretched approximately another 3.0 to 4.1 times. After leaving second draft roll 126 the tow continues around about 40% of the surface of a third draft roll 128 moving counterclockwise and opposite to the direction of second draft roll 126. An additional 1.1 to 1.3 draft may be applied between the second draft roll 126 and third draft roll 128.

After being drawn the yarn is passed through a circular jet 127 constructed as is described above and into a crimping zone which may be used in the practice of our invention. The crimper is provided with a clapper gate controlled by air cylinders so that the tow may move through the crimping zone in a continuous and unrestricted manner, thus imparting a substantially uniform crimp. The stretched and bulked yarn 130 after passing through circular jet 127 may be moistened by means of water or steam spray nozzles 134, which also controls the temperature of the yarn, prior to being fed into a stuffer box crimper through the bite of feed rolls 136 and 138. The water may be applied from a humidifier nozzle. Top feed roll 136 has a straight mechanical linkage (not indicated) to air cylinder 140, which is used to transmit pressure to the roll nip. Feed rolls 136 and 138 operate cooperatively, one being driven by the other either by gear or surface friction. The stufier box crimper outlet 142 is restricted by a clapper gate 144 which is pivoted at point 146 and controlled from air cylinder 148. The untreated yarn 130, which is in the form of a bundle may pass through a vapor cloud produced by the vapor nozzles 134 prior to passing through the bite of the feed rolls 136, 138 and next into the stuffer box crimping chamber formed between walls 150 and 152. As the yarn passes from the feed rolls 136, 138 into the stuffer box defined by walls 150 and 152, it is heated to semi-plasticity and further moistened by steam which is directed into the stutter box through inlets 154 and 156. The crimper clapper gate pressure should be less than about 30 p.s.i.g. and the steam pressure at least about 5 p.s.i.g. The steam admitted through inlets 154 and 156 also heats the stuffer box Walls 150, 152. This helps to keep the yarn in a semi-plastic state during treatment. The heated, moistened, semi-plastic yarn inside the stuffer box crimping chamber defined by walls 150 and 152 accumulates and fills the crimping chamber in a configurated yarn mass 158 which exerts a pressure and curled, is dried to a heat-set form 168 in a high amplitude, low frequency, crimped and curled state. The treated, heat-set, and dried yarn 168 upon leaving the heating chamber 166 may be removed from variablespeed endless conveyor 164 by any suitable means such as a plurality of mechanical packaging devices. Other suitable devices include beamers, ball-warping apparatus, or baling devices which would package a plurality of the yarns after treatment. The yarn could also be formed substantially directly into a non-woven yarn fabric, tufted into a carpet after plying and coning, or cut into staple fibers to be further processed.

It is sometimes helpful to apply a stream of air against the yarn 160 just as it leaves the crimping chamber restriction 142 to immediately cool the yarn and direct it toward the endless conveyor 164. A finishing agent may be applied to the yarn prior to packaging or further processing.

The air pressure (p.s.i.g.) at air cylinder 140 is adjusted to exert such pressure 'between rolls 146 and 148 as to prevent yarn slippage. The pressure applied to the clapper gate 144 is adjustable to obtain the desired amount of kinkiness of crimp in the yarn. Higher pressures produce a higher frequency, sharper crimp or curl. The pressure application at the air cylinders may also be accomplished in other ways, e.g., by dead weights, hydraulic devices, and the like.

The amount of moisture which may be applied to the sheet of yarn 130 from vapor nozzles 134 will control the hold-up time factor and temperature for the heat setting and drying of the yarn within the heat-setting and drying chamber 166.

An understanding of the functioning of the apparatus parts disclosed in the several figures as they may be used in this invention is already apparent to a substantial extent from the preceding description. However, a further understanding of the functioning as well as an understanding of the process of the present invention Will be had from a consideration of the examples which follow and which are set forth to illustrate certain preferred 7 embodiments of the instant invention.

EXAMPLES I-III Three samples of modacrylic tow (-80% acrylonitrile units) were extruded and processed in the steps diagrammatically indicated in FIG. 1 for continuous filament processing, including passage through a fingered or bustled jet such as illustrated in FIG. 2 and stutter-box crimper prior to heat treatment as continuous filament, high-bulk yarn. The extrusion speed, draft ratio and other specific processing conditions for these three samples are set out in tabular form hereinbelow.

Denier per Total Extrusion Jet-passage filament of denier of DJF. of Sample speed, Draft speed, Shrinkage, yarn prior lofted, lofted,

No. n1./m. ratio m./m. percent to jet heat-set heat set passage and yarn yarn heat-setting 1st Stage 2nd Stage on the clapper gate 144. When the mass pressure equals or exceeds the pressure produced by the air cylinder 148 operating on the clapper gate 144, the configurated yarn 160 then flows out of the stuffer box crimper restriction 142 to fall freelv on a variable speed endless conveyor 164 and be carried through a drying or heat-setting Tow dryer temperatures, C Relax roll surface temperatures, C Bulking or entangling, 25%

EXAMPLE IV chamber 166 in which the moist, hot yarn, now crimped unsteamed and steamed form with yarn passed through 7 a bustled jet such as that of FIG. 3. The results of this comparison are shown in the following table.

The above table illustrates that yarn jet treated in accordance with the process of the present invention (Sample 2) has a higher bulk both unsteamed and steamed than representative yarn which has not been jet treated.

EXAMPLES V-VI Separate samples of continuous filament modacrylic yarn were produced by dry-spinning and roll lubricated at the spinning machine, drafted (4.8/1) by the hot roll technique, and then passed through a jet such as depicted in FIG. 3 operated with air pressures from 10-35 p.s.i. Both samples were discharged on a dryer apron and heat set in a dryer operated with a hold-up time of 3 minutes and a temperature of 110l55 C. The heat-set yarn was then drawn through a lubricator by a set of draw rolls and wound. The following table indicates various conditions and properties of the apparatus used and yarn produced in these samples.

Example V Example VI (sample 1) (sample 2) Spinning speed (n1./m.) 46 45. 4 Top air temperature C.) 40 40-60 Bottom air temperature 0.). 140-150 140-150 Draft ratio 4. 6/1 4. 85/1 Relax ratio 99 99 Lubricant roll speed 3 Percent hot water shrinkage 48-52 42-49 Percent entanglement 23 20-30 D./f. from relax roll 8 5-9. 8. 0-9. 0 Heat setting temperature 140 140 Heat setting time (min.) 5 Winding speed (m./m.) 104 100-105 Speed at jet entrance (m./m.) 203 200-205 Speed at jet discharge (m./m.) 166 160-175 Heat-set, d./i'. (app) The yarn of Example V was of 1500 total denier/100 filaments produced at 50 lbs/day per cabinet and the yarn of Example VI of 2700 total denier/200 filaments produced at 100 lbs./ day per cabinet.

Continuous multifilament cellulose acetate tow was spun from a polymer dope, stretched and jet-treated with a shrouded jet according to the procedure of Examples V and VI to a yarn of 100 cu. in. per 1b. bulk. Polypropylene filaments spun from a melt were likewise treated with a jet such as depicted in FIG. 3 with resulting enhanced resilience and bulk in the textile product.

Although in the preceding description we have shown the use of the jet treatment of our invention prior to crimping, it may also be used after the crimping operation or without a separate crimping step.

It is believed apparent from the foregoing that we have provided a simplified procedure and apparatus combination for the manufacture of yarn of increased bulk and resilience whereby any tendency of the yarn to lose some of its crimp, entanglement or resilience is minimized and the crimp retention and speed of operation are substantially increased.

Although the invention has been described in considerable detail with particular reference to certain preferred embodiments thereof, variations and modifications can be effected within the spirit and scope of the invention as described hereinabove, and as defined in the appended claims.

We claim:

1. An apparatus arrangement for entangling yarn to a high degree of crimp retention comprising a tube entrance element and a flared tube-type exit member, an orifice plate and adjacent portions of said tube members being enclosed in a cylindrical housing whereby there is provided a chamber adapted to receive a gaseous fluid supplied thereto so that said fluid flows through the orifice plate and discharges through the exit member, said device being further characterized in that the exit member has attached to the end thereof spring means whereby the exit of the tow from the jet may be retarded enabling the gaseous fluid to entangle and bulk the yarn, means for introducing tow to said tube and conducting same therefrom and stuffer-box crimping means in association therewith, and heat treating means positioned subsequent to said spring means whereby the tow may be set in the form of a high-bulk, high crimp retention yarn, said heating means having in association therewith means for conducting the tow thereinto, therethrough and therefrom.

2. Apparatus for the manufacture of high-bulk yarn comprising in series a plurality of draft rolls consisting respectively of an idler roll, a preheat roll, a first draft roll, a second draft roll and a third draft roll, said draft rolls capable of stretching tow up to 850% of its original length prior to drafting thereon, a circular jet positioned after and downstream from said plurality of draft rolls, said jet comprised of a chamber for movement of tow therethrough, means for supply of gaseous fluid thereto and exit therefrom, and tow-retarding extension members at the exit end thereof to retain the yarn that has been entangled and bulked by the gaseous fluid, stuffer-box crimping means positioned after said exit end of said jet, heat-treating means following said crimping means, all of said apparatus co-operating as means whereby a highbulk, high crimp retention and high crimp recovery yarn product may be produced from spun continuous filament tow.

References Cited UNITED STATES PATENTS 5/1962 Cook et al. 28l

7/1963 Caines et al. 28l X

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