US3264389A

US3264389A - Method for spinning special yarns

Info

Publication number: US3264389A
Application number: US452668A
Authority: US
Inventors: James G Sims
Original assignee: Monsanto Co
Current assignee: Monsanto Co
Priority date: 1962-12-26
Filing date: 1965-05-03
Publication date: 1966-08-02
Anticipated expiration: 1983-08-02
Also published as: NO115812B; LU45083A1; BE641893A; FR1378565A; CH409227A; DE1435571A1; GB1010143A; NL302605A

Description

Aug. 2, 1966 J. G. SIMS METHOD FOR SPINNING SPECIAL YARNS I4 I l IZ'. I3 I I8 2 Sheets-Sheet l FlG.l.

ATTORNEY Aug. 2, 1966 J. G. sums METHOD FOR SPINNING SPECIAL YARNS Original Filed Dec. 26, 1962 2 Sheets-Sheet 2 FIG. 3.

ATTORNEY United States Patent 3,264,389 METHOD FOR SPINNING SPECIAL YARNS James G. Sims, Pensacola, Fla, assignor to Monsanto Company, St. Louis, Mo., a corporation of Delaware Original application Dec. 26, 1962, Ser. No. 247,006. Divided and this application May 3, 1965, Ser. No. 452,668

2 Claims. (Cl. 264-131) This is a division of US. application Serial No. 247,006, filed December 26, 1962.

This invention relates to'an apparatus and method for spinning synthetic filament yarns and to special filament yarns produced therefrom. More particularly, this in-- vention relates to a novel method and apparatus for quenching thermoplastic filaments and to special bumpy filament yarns produced therefrom.

conventionally, freshly spun molten filaments are quenched by passing them through a cooling unit referred to as a quench chimney, a quench chamber, or a quench box. Freshly spun molten filaments issuing from a spinneret pass through the quench chimney and extend to a convergence guide mounted at the bottom thereof where the filaments are bundled into a yarn. One side of the chimney is open to a plenum chamber from which air under pressure is cross-directed into the path of the filaments. The filaments are cooled by the airstream, and the air is then exhausted through an open side of the chimney. In the conventional process and method,

heat from the filaments is transferred by convective circulation of air and depends on the film coefficient and the temperature difference between the filament surface and the ambient gas.

Endeavors to improve upon the described filament yarn spinning process and equipment with objectives of providing more uniform cooling and higher quenching rates of filaments are constantly being made.

Further efforts are directed toward adapting filament yarn spinning practices for the production of novelty yarns which have become commercially attractive for their refractive and ornamental effects.

It is an object of this invention to provide a novel method and apparatus adapted to rapidly and uniformly quench freshly spun filaments of polymeric structure by passing the filaments through a fluidized bed of fine heatconducting particles.

A further object is to produce special bumpy filament yarns.

According tothe novel method and apparatus embodying the invention, an elongated, tapered tube is adapted to be uprightly positioned beneath a spinneret to receive freshly spun molten filaments issuing therefrom. The tapered tube is adapted byjoining an air manifold and an air induction means therewith to effect a fluidized bed of fine particles in the path of the filaments as they pass through the tube. The air ,manifold means provides an airstream in the tube which flows counter to the direction of the filaments and the air induction means provides a source of fine particles which are entrained within the airstream. By controlling pressure and velocity of the airstream, a stable fluidized bed of fine particles .is established in the tube.

If inert type particles are used, the particles contact the filaments and absorb the heat therefrom, thus promoting cooling of the filaments. Where fine inert particles of harder structure than the spun filaments are used, the filaments are impinged upon and are dented so that the resulting filaments are pitted or pockmarked. Where a fusible type fine particle is used, the particles fuse to the filaments and provide a novel nubby yarn.

3,2643%? Patented August 2, 1966 ice The detailed description of the novel quench method and apparatus and of the novelty yarns produced therefrom which follows taken in conjunction with the acompanying drawing provides a better understanding of the invention.

In the drawing:

FIGURE 1 is an elevation view with parts cut away showing the novel quench apparatus and method,

FIGURE 2 is a cross section view taken through 22 of FIGURE 1,

FIGURE 3 is an elevation view showing a nubby type novel yarn of the invention, and

FIGURE 4 is an elevation view showing a pockmarked type of novelty yarn of the invention.

The embodiment shown in the various figures in the drawing are illustrations of the invention and are not intended to be limitative thereof.

Referring to the drawing, a preferred construction of the novel spinning apparatus embodying the invention, as shown in FIGURES 1, 2, comprises an elongated vertically positioned tapered tube or vessel 1 having an axial chamber 2 extending therethrough. Tube 1 can be of integral construction but, preferably, is constructed in three sections: an upper section 3, an intermediate section 4, and a lower section 5. The

sections

3, 4, and 5 are sealingly and clampingly connected therebetween by means of flanges 6 provided at the joining ends of the sections, gaskets 7, and bolts and nuts S. Upper section 3 is relatively short in length and has a wide funnelform mouth at its top and extends downwardly therefrom at a high degree of taper to join with intermediate section 4. A spinneret 9 for extruding filaments 10 of thermoplastic material is positioned adjacent the funnelform mouth of section 3. Section 4 is the longest section and has a constantly decreasing degree of taper from its upper to lower end where it joins with section 5. Section 5 is substantially of the same width along most of its length. Section 5 extends from the lower end of section 4 for a distance and then is provided with a flared portion that terminates at its lower end in a cylindrical portion having a flange 11 formed about its outer periphery inwardly from the end thereof.

An air manifold 12 having a pressure chamber 13 defined therein is sealingly and clampingly connected to the flange 11 surrounding the cylindrical portion of section 5 by a gasket 14 and bolts 15. The cylindrical portion of section 5 depends into the pressure chamber 13 and has a space defined therearound. Manifold 12 has a chimney or sleeve member 16 of a smaller diameter than tube 1 which is coaxially arranged therewith. Manifold 12 extends upwardly into section 5 and defines an annular space 17 between chimney 16 and the wall of section 5. Preferably, chimney 16 is tapered so that it gets progressively wider as it extends into section 5. A smooth surfaced collar is provided at the inner end of chimney 16 to prevent damage to filaments that normally enter the chimney. Annular space 17 permits communication between chamber 13 in manifold 12 and chamber 2 of tube 1.

A gas, such as air under pressure from a source thereof, is normally delivered to pressure chamber 13 of manifold 12 by lines 18 adapted to be connected to suitable connectors press-fitted in ports provided in manifold 12.

Drain plug 19 is provided in manifold 12 to permit removal of particles which settle therein.

Longitudinal, slotted support members or braces 20 are affixed to tube 1 at opposite sides thereof by suitable bracket 21 and bolt and nut assemblies. Support members 20 are mounted on respective fixed clamps 22 which extend through the slots of support members 20 and which section 4-widens as it extends upwardly.

provide vertical adjustment of tube 1 .to permit access to spinneret 9.

To permit a constant check to be made of the process and operation in the interior of tube 1, covered aperture or Window 23 is provided in section 4 of tube 1.

An induction device 25 is provided to introduce fine. particles or other particulate matter into annular space L 17. Induction device 25 comprises a hopper 24 normally supplied with fine particles 26, a mixing chamber 271a gate 28 for admitting the particles into the mixing chamber 27, anda blower and motor assembly 29 that gen-- erates an airstream for transporting the particles from the mixing chamber 27 to the annular space 17 of tube 1 via duct 30 having a flexible joint. nected at its one end to an air inlet fitting fixed to the Duct 30 iscon- I lower end of section'5 and opening into annular space '17. and at its opposite end the duct is connected and open to mixing chamber 27.

A recirculating pipe- 31 :is; connected at one end to an adapter mounted in an inlet port formed at the upper'end of section 3; and at its opposite end the recirculating pipe is. connected to an adapter mounted in an inlet port formed in section 5. The recirculating pipe 31 is provided to stabilize the level of the bed and to collect fluidized par ticles which become disengaged from the'bed and to return them to space 17;

Filaments 10, after passing through tube 1, are directed through a convergence guide 32 which convergesthe filament bundle for forming a yarn 33.. Yarn 33 is then advanced through a pigtail guide 34 and thence through a traverse guide 35 before being collected on a bobbin 36 of take-up device 37.

In' operation, it will initially be assumed that the apparatus and method of the invention is operated to quench filaments; i.e., primarily to cool freshly spun filaments. In this case tube 1 is adjusted by clamps 22 to be axially aligned with spinneret 9, with the top end of tube 1 approximately two feet below the spinneret 9. A polymer compound such as nylon for forming filaments is pumped through spinneret 9 and a bundle of filaments 10 are extruded therefrom. By employing a vacuum device, such as an aspirator gun inserted within chimney 16, filaments 10 are pulled downwardly through chamber 2 of tube 1 and through chimney 16. Filaments 10'are then threaded through the convergence guide 32, advanced through pigtail guide 34, forwarded to the traverse guide 35 and then laid on driven bobbin 36 of the take-up device 37. Air.

under pressure is then delivered to pressure chamber 13 of manifold 12 through lines 18. The air will flow up.-

wardly from chamber 13 into annular space 17 in section 5 of tube 1 at a high velocity because of the narrow dimensions of annular space 17 and will continue to rise into section 4 with a slight decrease in velocity because Flowing into section 3,. the, airstream will decrease further in velocity due to the progressively rapidly widening of section 3;

Having. established an airstream of predetermined velocity and'pressure flowing counter to the flow of fila ments 10, fine inert particles of glass material and of 515 micron size are dispensed from hopper 24 to the mixing chamber 27 past gate 28. The airstream produced by blower 29 then forces the. inert glass particles into annular space 17 of tube 1. The particles are entrained within the high velocity airstream traveling through annular space 17 and are carried rapidly upward into section 4. The particles are further transported upwardly through section 4 at a progressively decreasing velocity due to the configuration of this section and the particles are thereafter further lifted into section 3. I At this level a pressure drop is realized; and a coefiiient of the air pressure to weight of the particles is attained such that the particles do not rise further but are suspended by the airstream and form a'stable fluidized bed.

As is characteristic of fine particles in a fluidized state, the particles move at random within the bed and contact therewith. A high rate of heat transfer resultsfrom the large particle surface available for fluid-solid contact. The temperature within the bed remains substantially uniform.

Should the particles be pneumatically carried from the fluidized bed, they will be returned to the system .by recirculating pipe'31.

Where it is desired to spin pockmarked or pitted filaments, fine inert'infusible particles such as crushed quartz having sharp edges and a higher degree of hardness than the molten filaments is used to establish the'fiuid bed. Yarn of this type is shown in FIGURE 4 andis denoted by reference numeral 38; ,In this case the particles .upon contact with the filaments dent and deform the surface of the filament but do not-adhere firmly thereto so that upon solidification the filaments have .small indentations at random points 'onthe filaments;

Where it is desired to, spin nubby filament yarn 39, as

shown in FIGURE 3, fine particles such aspolyethylene powder or powdered sugar of fusible characteristic are used .toiestablish the fluidized bed. Under this condition, the particles partially fuse to the filaments and when the filaments are cooled a nubby type yarn islproduceda Various'effects and profiles can be provided by using particles of different shapes: spheroidal, cubical, cylindrical, etc. Dissolution of solublerparticles adhering to the filaments (such as sugar), have irregular craters in the yarn surface, resulting inyarn illustrated in FIGURE 4.-

Aerosol fogs of water,,inorganic, or organic liquids may.

be generated and delivered to the quench tube 1.? Highly volatile liquid-droplets provide great heat absorption capacity. Localized surface nubs are formed at the point of dropletimpingement upon the still molten filament to yield a pimpled or wart-likesurfacea It will be understood that changes and variations may be made Without departing from the spirit and scope of the invention as defined in theappended claims.

Whatis claimed is: 1. A fluidized bed filament yarn spinning method comprising the steps of,

(a) extruding a group of molten filaments of thermoplastic material,

(b) passing said filaments longitudinally in one direction through a quenching zone,

(c) converging. said filamentsto form a yarn after they pass out of said quenching zone,

((1) collecting said yarn,

(e) establishing. an airstreaminsaid quenching zone flowing in an opposite direction to said one direction of filament travel,

(f) entraining fine particles of inert material into said airstream,

(g) forming a fluidized bed of said fine particles in said quenching zone in surroundment of and adjacent to the a entrance .of said filaments-into said a quenching zone,

(h) whereby saidparticles inisaid fluidized bed move about at random therein and contact said filaments thereby effecting transfer'of heat from said filaments to said particlesfor cooling said filaments.

2.1 A fluidized bed 'filament'yarn spinning method as claimed in claim 1 wherein fine particles of a fusible type material are used to form'the fluidized bed and wherein said fusible fine particles partially fuse to. the molten filaments and produce a resulting yarnrhaving a nubby appearance.v

(References on following page) 5 6 References Cited by the Examiner 3,072,968 1/ 1963 Watson et a1 264-176 UNITED 3,088,188 Kl'lIldSfiIl 57-140 3,1 ,99 6 1 64 3/1936 Taylor 264131 X 37 0 9 Carranza 57 140 1/ 1948 wuvburger 28-82 5 STANLEY N. GILREATH, Primary Examiner. 12/1956 Davls 57-140 X 7 1957 Kahn 57 1 0 MERVIN STEIN, Exammer. 5/ 1960 Carey et a1 57149 X D. E. WATKINS, Assistant Examiner. 11/1962 Keen 264-131

Claims

1. A FLUIDIZED BED FILAMENT YARN SPINNING METHOD COMPRISING THE STEPS OF, (A) EXTRUDING A GROUP OF MOLTEN FILAMENTS OF THERMOPLASTIC MATERIAL, (B) PASSING SAID FILAMENTS LONGITUDINALLY IN ONE DIRECTION THROUGH A QUENCHING ZONE, (C) CONVERGING SAID FILAMENTS TO FORM A YARN AFTER THEY PASS OUT OF SAID QUENCHING ZONE, (D) COLLECTING SAID YARN, (E) ESTABLISHING AN AIRSTREAM IN SAID QUENCHING ZONE FLOWING IN AN OPPOSITE DIRECTION TO SAID ONE DIRECTION OF FILAMENT TRAVEL, (F) ENTRAINING FINE PARTICLES OF INERT MATERIAL INTO SAID AIRSTREAM, (G) FORMING A FLUIDIZED BED OF SAID FINE PARTICLES IN SAID QUENCHING ZONE IN SURROUNDMENT OF AND ADJACENT TO THE ENTRANCE OF SAID FILAMENTS INTO SAID QUENCHING ZONE, (H) WHEREBY SAID PARTICLES IN SAID FLUIDIZED BED MOVE ABOUT AT RANDOM THEREIN AND CONTACT SAID FILAMENTS THEREBY EFFECTING TRANSFER OF HEAT FROM SAID FILAMENTS TO SAID PARTICLES FOR COOLING SAID FILAMENTS.