US2961223A - Additive injecting and blending apparatus for filament spinning - Google Patents

Description

Nov. v22, 1960 w. P. DOOLEY ADDITIV'E INJECTING AND BLENDING APPARATUS FOR FILAMENT SPINNING Flled Aprll 25. 1957 KPH Q I 5523a Zzt v n\ All N\ Q G. 02.25% E ,7 I #553935 I: 2T uifieqq hlm m Q w gm on United States FateiitfOTi I ADDITIVE INJECTING AND BLENDING APPA- RATUS FOR FILANIENT SPINNING William P. Dooley, Wallingford, Pa., assignor to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware Filed Apr. 25, 1957, Ser. No. 655,055

4 Claims. (Cl. 259-9) This invention relates to liquid injection and blending apparatus, and more particularly to a device for injecting a secondary stream of additive-containing viscose into aprimary stream of viscose and thoroughly blending the. mixture pr1or to spinning. This case is related to Serial No. 477,904, filed December 27, 1954, now Patent No. 2,798,698, same assignee.

The problems connected with the injection of one stream of a liquid such as viscose into a second viscose "I stream are, to a considerable extent, influenced by the 1 viscose is such that the injected stream tends to resistcomplete mixing and therefore relatively violent agitation and blending is required to achieve homogeneity.

A primary object of the invention therefore is to provide a combined injection apparatus and blender which is highly efficient in its blending action and leaves no stagnant zones.

A still further object of the invention is to provide an improved injection blender having a two-stage blending element mounted ona common shaft, the first stage comprising a high speed agitator of relatively small diameter and the second stage comprising a series of rotors and stators of relatively larger diameter. A more concise object is to improve the preliminary dispersator described in Patent No. 2,798,698.

"Furtherobjects will be apparent from the specification and drawings in which:

Figure 1 is a flow diagram showing the pre-blender of this invention in place in a viscose spinning system;

Figure 2 is an enlarged sectional view of the injection blending device of this invention;

Figure 3 is a front view of the wiper rotor used in the construction of Figure 2; and

Figure 4 is an isometric view of one of the rotors of Figure 2.

The invention comprises essentially the provision of a cylindrical housing having two mixing or blending zones in series, the first zone employing a novel wiper otor, and the second a plurality of alternating stator and rotor elements mounted along its axis. The liquids to be blended flow axially through the rotor and stator elements and the rotor discharges the mixture of primary and secondary liquids tangentially through a discharge port at right angles to the axis of the rotor shaft. The secondary or additive stream is delivered to the preliminary mixing zone immediately in front of the stators and rotors. The rotor shaft at a point within this premixing zone is provided with the wiper rotor which functions as a preliminary stirring element to initially smear the additive stream into a circular ring within the main viscose stream before the latter enters the rotor-stator mixing zone.

. Referring ,to Figure 1, a stream of viscose passesv through line 10 to a final blender 17. A portion of the viscose is metered off from line 10 through shunt line.

12 into pre-blender 14 wherein it is mixed with a stream of additive from line 13. The resulting blended stream of viscose and additive (seed viscose) is metered through;

metering pumps 15 and line 16 which draw more liquid than is supplied through line 12, so that the difference is made up by the additive drawn in through line 13. The seed viscose stream is pumped into final blender 17 wherein it is injected into and mixed with the main viscose the top of injector 23 and the periphery of Wiper 25 is stream from line 10. The final blend from blender 17 is passed through line 18 to suitable spinning means. This system as described is of primary use when the additive from line 13 is an abrasive pigment dispersion; such an.

additive would cause severe wear and abrasion on metering pumps 15 if the additive was not dispersed to some extent in the viscose; this is the function of pre-blender 14. This basic system is covered in applicants copending application Serial No. 474,154, filed December 9, 1954 now abandoned.

Referring to Figure 2, pre-blender 14 is contained in a cylindrical housing 20 which has an inlet flanged coupling 21 through which the primary stream enters the housing via orifice 22. The secondary stream from line 13 is injected into the main stream through injector 23.

Wiper rotor 25, mounted on shaft 26, continuously rotates past the nipple of nozzle 23 so as to immediatelybegin dispersing the additive into the viscose as soon as it enters the blender. This prevents the formation of crusts and agglomerates of pigment at the entry point.

It also prevents the formation of viscose gels when the additive is of limited compatibility in viscose, such as polyvinyl alcohol or Pycal (4 dendrophenol). have low solubility with viscose. The clearance between slight, on the order of inch; the wiper should pass as' close to the injector tip as possible since its purpose is to 'wipe the additive form the injector outlet and to spread the additive in a thin film at high speed.

As seen in Figure 3, wiper rotor 25 is in the form of I a cup-shaped member having curved fingers 25a extending toward the orifice 22'. The curved fingers 25a form an interrupted cylindrical surface which lies close to the discharge of nozzle 23. Wiper 25 is secured to shaft 26 t (Figure 2) by key 27 which fits keyway 25b of the wiper,

and is tightened to the shaft by nut 29.

The secondary blending stages comprise a series of rotors 30, 30a, 30b and alternating stators 40, 40a. The rotors are keyed to shaft 26, which in turn is supported in bearing sleeve 28, the latter being seated in recessed flange 21a. Each stator 40, 40a contains a series of perforations 41 preferably arranged in concentric rows to permit passage of the liquid and to break up the initially mixed streams into relatively fine filaments. Each stator is centrally recessed to permit sufficient clearance for key 27 on shaft 26 to clear the stators during rotation.

The final rotor 30b is in line with the axis of discharge fitting 45. which is at right angles to the axis of the rotors and shaft. In this way the rotor 30: functions, in addition to its mixing action, as a centrifugal pump to boost the discharge pressure from the blender and thus eliminate the necessity for installing a secondary booster pump in the line should the pressure drop be considered excessive. This tangential rather than axial outlet also permits the entire shaft and rotor assembly to be carried in very adequate outbo rd su ports. All rotors are of identical construction (Figure 4). Each rotor has a solid hub that is keyed to shaft 26, and the periphery of the rotors comprises a plurality of spokes 33 having a substantially rectangular cross-section. In addition to the spokes, I provide two or more vanes or paddles 34 spaced Patented Nov. 22,1960,

These COSB.

plicants .copending applications-Serial No. 477,904 new- Patent No. 2,798,698 in that it has a predictable capacity at various speeds. lTheudis'persatoriof'that application loses proportional capacity at low speeds andtends to act as a solid body .at:hi-gh:speeds in highwiscosity vis- The contribution to capacity of the blender by wiper rotor-25 is at least twice that ofthe said dispersator.

Ina typical embodimentiof the inventionlfinal'blender 17 has an inner diameter of four. inches, has four rotors and three stators and'the wiper'rotor, andoperates at 1800 'r.p.rn., which results ina capacity of 40 gallons per minute; preblender 141hasa two-inch inner diameter,

three rotors and two stators and the wiper rotor, and' when operated at 1800 rpm. has :acapacity of about 9 gallons per minute. The speed'of the pre-blender 14 is adjusted independently of'the final blender 17 to give the desired 'pre-blendercapacity. The percent of additive in jected varies widely'according'to what the additive is and the elfect desired,:whetherpigment or other viscose chemical-additives. For example in the spinning of ajpale pink .colorspun rayon yarn as :compared toa black color spun yarn the ratio'of pink pigment to carbon black is 1:2,000. Also asmall denier filament requires more pi'gment than a large denier filament toattain the same degree 'of color. Thus, in' spinninglOO pounds of a 15 denier yarn as compared to spinning 100 pounds of'a 1 .5 denier'yarn of the same color it' is necessary to use about three times 'as much pigmentifor the'finer denier. Hence all of these factors must be taken into consideration in adjusting the blenders for each run.

'The combined injectionblender, as described above,' is admirably suited for use with relatively thick viscous liquids'such as viscose. It is simple, effective, and the two'stages provide exceptionally efiective'blending for the addition of any desired secondary fluid. As illustrated above, this is preferably "an additive intended to accomplish an improved physical characteristic in theextruded filaments, such as a delustrant or a pigmented'mixture for yarn coloring. This doesinot excludesuch'additives as surfactants or greening agents used in high strength yarns and fibers whereby the-process is simplified, resulting in economic advantage or in commercial practicality. Depending upon the particular installation, the design may be modified to operate as a booster pump if the elimination of pressure drop through the device is important. Low cost, adequate capacity andelimination of stagnant areas-together with very completeblending are important features of the design.

I claim:

1. An injectionblender for viscous material comprising a cylindricalhousing, means for admittingya viscous liquid into one end of said housing, an injector'extending through said housing-near theend where the viscous liquid is admitted for introducing an additive liquid, said injector having an opening dire'ctedtoward the axis of said housing, a discharge port in said housing axially removed from the points of admission of the liquids, a rotatable shaft. extending throughthe other-end of said housinggafirststage agitator secured to said'sha'ft within said housing, saidagitator comprising a cup-shaped member. having .curved fingers extending axially toward the point of admission of: the viscous liquid, said curved fingers forming an interrupted cylindrical-surface which lies close to and directly in line with the opening of said injector-so. that as said agitator rotates the additive liquid is wiped .intoland dispersed in the viscous liquid, and a second stage? agitator in said housing between said first stage:agitator andisaid discharge port, said second stage agitator. comprising :a pluralityof rotors mounted onsaid shaft .and a plurality of stationary perforated plates located betweenv said rotors, the rotors and stationary plates beingarrangedwith arotor aheadof each plate.

2. The apparatus set forth in claim 1 wherein one of the rotors ofsaid secondstage agitator is located directly adjacent said cup-shaped member.

3. The apparatus set forth in claim 1 wherein'said rotors have a diameter'only slightly less than'the internal diameter of said cylindrical housing.

4. The.apparatus-set'forthin claim 1 wherein said discharge :port extends radially through said housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,948,871 Quehl Feb. 27, 1934 2,509,267 Goodwin May 30, 1950 2,650,168 Dijk Aug. 25, 1953 2,791,404 Kelly May 7, 1957 2,798,698 Dooley July 9,

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