US3070981A

US3070981A - Method of and apparatus for forming strands of filaments

Info

Publication number: US3070981A
Application number: US860378A
Authority: US
Inventors: Philip J Frickert
Original assignee: Owens Corning Fiberglas Corp
Current assignee: Owens Corning
Priority date: 1959-12-18
Filing date: 1959-12-18
Publication date: 1963-01-01
Anticipated expiration: 1980-01-01

Description

Jan. 1, 1963 P. J. FRICKERT 3,07 ,981

METHOD OF AND APPARATUS FOR FORMING STRANDS 0F FILAMENTS Filed Dec. 18, 1959 A JNVENTOR.

PHIL/P J. Ric/(5 9T BWZW Fatented Jan. 1, 1963 3,fi7tl,981 METHQD OF AND AFPARATEE FOR FQRMING 6F FELAMENES Philip J. Frieirert, Anderson, 3.6., assignor to @wens- (Iorning Fiherglas Qorporation, a corporation of Dela" ware Fi'ted Dec. 13, 1959, Ser. No. 86%,378 2 Qlaims. ((13. 654) This invention relates to method of and apparatus for forming continuous filaments from heat-softenable min- .eral materials and more especially to a method of forming strands of fine continuous filaments from heat-softened glass.

It has been a practice, in forming fine continuous filaments, to flow a plurality of streams of heat-softened glass or other fiber-forming material from a feeder or bushing and winding a strand of filaments formed from the streams upon a rapidly rotating collector to attenuate the streams to filaments. In order to increase the output or throughput of a feeder or bushing, it has been a practice to attenuate two groups of streams into two strands of filaments by simultaneously Winding the two strands upon collectors or rotating sleeves wherein the two groups of streams providing the respective groups of filaments for the strands are arranged one at either side of the minor or transverse axis of a rectangular bushing whereby one strand of filaments is formed of a group of streams at one side of the transverse central plane or axis of the bushing and the other group formed from streams at the opposite side of the transverse central plane.

The feeder or bushing is usually heated electrically by flowing current lengthwise of the feeder or bushing through connections with lugs or terminals provided at the ends thereof. Due to the rectangular shape of the feeder and the lengthwise flow of electric current, variations in the temperature of the glass occur lengthwise whereas little or no variation in temperature occurs at any transverse region of the feeder or bushing. In multiple filament double strand arrangements taken from so-called double bushings where the respective groups of filaments are derived from groups of streams, one group flowing at each side of a transverse central plane of the bushing, temperature differentials existent lengthwise of the feeder effect differences in viscosity of the glass whereby variations in the size of filaments as between the two groups of filaments may be substantial, imp-airing the quality and uniformity of the strands and yardage variations. Furthermore, it is believed that the feeder throughput oscillates around a transverse axis of the feeder which, in a measure, aggravates the tendency toward nonuniformity of streams and filaments formed therefrom where substantial temperature difi erentials occur in the glass lengthwise of the feeder.

The invention embraces the provision of a method of concomitantly forming strands of filaments from groups of streams of heat-softened mineral material emanating from a feeder wherein the groups of streams lie in parallel relation lengthwise of the feeder and the filaments of each group derived from parallel zones of the material lengthwise of the feeder thereby reducing the coeificient of variation in yardage of the respective strands.

An object of the invention resides in a method of flowing groups of streams of heat-softened material from a feeder and attenuating at least two strands formed from the groups of filaments by winding them on a collector, the filaments of each strand being derived from streams of material flowed from groups of orifices arranged in side-by-side relation lengthwise of a feeder whereby to attain improved distribution of filaments of differential sizes in the respective strands.

Another object of the invention resides in a method of flowing parallel groups of streams from an elongated feeder wherein each group. of streams is derived from rows of orifices arranged lengthwise of the feeder and filaments attenuated from the respective groups of streams gathered into strands of filaments which are concomitantly wound upon a collecting medium at a speed to effect attenuation of the streams of the groups to fine filaments.

Another object of the invention resides in a method of flowing groups of streams of glass from a double bushing whereby the filaments of each of two groups are flowed from regions or zones of the glass in a feeder in a manner to distribute filaments of like variations in size through each of two strands formed from the filaments to effect a minimum coefficient of variation and improved stability in the yardage of the strands.

Another object of the invention resides in a feeder formed with two groups of orifices or orificed tips oriented in side-by-side relation lengthwise of the feeder or bushing whereby to minimize the effect of viscosity differentials in the glass lengthwise of the feeder and the throughput of molten glass or other heat-softened filament-forming material flowing through the orifices or tips of each group is substantially equalized or stabilized whereby strands of continuous filaments attenuated from the respective groups have a minimum yardage coefficient of variation.

Further objects and advantages are within the scope of this invention such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinations of parts, elements per se, and to economies of manufacture and numerous other features as will be apparent from a consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

FIGURE 1 is a side elevational semidiagrammatic view of a form of apparatus for carrying out the method of the invention;

FIGURE 2 is a front elevational semidiagrammatic view of the arrangement shown in FIGURE 1;

FIGURE 3 is a bottom plan view of a feeder illustrating one pattern of orientation of orifices formed therein, and

FIGURE 4 is a front elevational semidiagrammatic view of a double bushing of conventional construction.

The method and apparatus of the invention are illustrated as particularly usable in the formation and collection of dual strands of fine continuous filaments formed from heat-softened glass, but it is to be understood that the method and apparatus of the invention may be utilized in forming or processing continuous filaments formed from other heat-soften'able filament forming materials.

With particular reference to FIGURES 1 and 2, the arrangement includes a rectangular shaped feeder or bushing 10 adapted to contain a supply of heat-softened material such as glass of the character or composition usuable for forming textile filaments or fibers. The feeder 10 may receive a supply of heat-softened glass from a forehearth of a glass furnace (not shown) or the feeder equipped with heating means for reducing glass marbles or cullet to a flowable condition.

In either type of supply, the feeder it} is electrically heated by current supplied by conductors 11 connected with lugs or terminals 12 provided at the ends of the feeder to maintain the heat-softened material or glass at the proper temperature and viscosity. The bushing or feeder lti is formed with a bottom wall or floor 14 provided with groups of orificed tips or projections 16 through which streams of glass are delivered for attenuation to continuous filaments.

The pattern or orientation of the orificed tips 16 in the bottom of the feeder for carrying out the method of the invention is shown in FiGURE 3 and will be hereinafter described in detail. The streams flowing from the orifices in the orificed tips 16 associated with the floor 14 of the feeder are attenuated into two groups of continuous filaments gathered into separate dual strands by winding the strands upon a collecting medium.

As shown in FIGURES l and 2, a housing 20 contains means journally supporting an arbor or shaft 22 which is adapted to be rotated at a comparatively high speed by a motor (not shown) contained within the housing 24 In the embodiment illustrated, the

dual strands

24 and 28 of filaments are wound upon a medium or surface which, as illustrated, comprises a tubular sleeve 30 upon which the strand 24 is Wound and a tubular sleeve 32 upon which the strand 28 is Wound.

In the embodiment illustrated, the strand collecting sleeves 3t and 32 are mounted upon the single rotatable arbor 2'2, but it is to be understood that the sleeves or strand collecting media may be mounted on separate arbors driven by suitable means. The collector sleeves 3d and 32; are rotated at a comparatively high speed to advance the strands of filaments and hence attenuate the streams to filaments at linear speeds of upwards of ten thousand or more linear feet per minute.

Disposed intermediate the feeder 10 and the winding sleeves are filament gathering means or

members

34 and 36 supported respectively upon brackets 38 and M). The filament gathering means 34 and 36 may be in the form of grooved members as illustrated. The

strands

24 and 28 are influenced by traverse means 42 and 44 mounted upon a rotatable and reciprocable shaft 46 for simultaneously traversing the respective strands lengthwise of the collectors 3t and 32 whereby the strands are wound into strand packages designated respectively 43 and Stl.

The traverse supporting shaft 4-6 is actuated by conventional means contained within the housing 20 for rotating the shaft to secure micro traverse of each strand and for reciprocating the shaft and traverse means lengthwise of the sleeves 3t) and 32 for securing a so-called macro traverse motion for distributing the strand lengthwise of the sleeves in forming the strand packages. The traverse means 42 and 44 influences the deposition of the strands on the packages so that successive convolutions of strand are angularly disposed, one with respect to another, to minimize the liability of the convolutions sticking together so as not to impair unwinding of the strands from the packages in subsequent processing operations.

The filaments 52 comprising one group 53 formed from one group .17 of streams delivered from the feeder 10 are gathered into the strand 24 by the filament gathering means 34 and the filaments 54 formed from a second group 18 of the streams are gathered into a strand 28 by the gathering means 36. Means is provided for applying a lubricant, sizing or coating to the filaments of the respective groups prior to the convergence of the filaments into strand formations.

Receptacles

53 and 60 are disposed respectively adjacent the groups of filaments above the filament gathering means 34 and 36 as shown in FIGURE 2. The bracket 38 is supported from the receptacle and the bracket 4% is supported from the receptacle 6% Each receptacle is adapted to contain a lubricant, size or coating for application to the filaments. The receptacles are respectively provided or equipped with rolls supporting applicator-s or belts 62 and as for delivering a lubricant, size or coating onto the filaments of the respective groups through wiping contact of the filaments with the surfaces of the belts.

The applicator supporting rolls are preferably rotated at a comparatively slow speed and the belts are adapted to continuously acquire a film of the material for transfer onto the filaments. it is preferably to provide a continuous circulation through the receptacles of coating material from a supply and to accomplish this the receptacles are provided with inlet tubes 65 and overflow tubes 66 connected with a supply of filament coating material and a suitable pump (not shown to maintain continuous circulation of coating material in the receptacles.

The method of the invention of attenuating dual strands of filaments resides in attenuating each group of filaments from groups of streams of glass flowing through groups of orifices or orificed tips in the feeder wherein the streams from which the filaments of a group are formed are disposed in parallel relation lengthwise of the feeder. As shown in FIGURE 2, the filaments 52 of one group are obtained from a substantial number of orificed tips 15 flowing streams 17 throughout substantially the length of the feeder, the filaments being converged by the gathering means as in a fan-like pattern or configuration 53 whereby filaments in the strand 2d are obtained from streams flowing from orifices arranged throughout substantially the length of the feeder.

The filaments 54- are formed from a second group of streams l8 flowing from orificed tips 16 arranged throughout substantially the length of the feeder and in transverse parallel relation to the first group of streams 17, the filaments 54 being converged into a strand by the gathering means 36, the converging filaments being in a fan-like pattern 55 as shown in FIGURE 2. The fan-

like patterns

53 and 55 of the respective converging groups of

filaments

52 and 54 are in transverse overlapping relation as shown in FIGURE 2.

FIGURE 3 illustrates a bottom view of a portion of a floor 14 of the feeder ltl showing the lengthwise arranged

groups

15 and 16 of orificed tips, the groups being preferably spaced transversely from a median plane AA lengthwise through the feeder. In the embodiment illustrated in FIGURE 3, there are four rows of orificed tips 15 at one side of the median plane AA lengthwise of the feeder and four rows 17 at the opposite side of the plane AA. The orificed tips are preferably arranged in transverse rows in pairs which are spaced as illustrated to accommodate fins or heat absorbing members 72 of a fin cooler 74 arranged beneath the feeder.

Water or other heat absorbing fluid is circulated through the tubular portion of the cooler 74 to convey away heat absorbed from the glass streams l7 and 18. The function of the fin cooler is to absorb heat from the streams of glass flowing through the orificed tips to increase the viscosity of the glass of the streams providing for improved attenuation of the material to filaments.

This arrangement enables maintaining the glass in the feeder at a higher temperature and hence lower viscosity to facilitate more uniform flow of the highly liquid glass through the orifices in the tips. The glass streams which flow through the orifices of tips 15 are attenuated into filaments 52 forming one group of filaments converged to provide the strand 24, while the streams flowing through the orifices of the tips 16 are attenuated to form the filaments 54 of the second group which make up the strand 28.

It will be apparent that the respective groups of streams flow from parallel zones or regions of the molten glass in the feeder. As the feeder 14B is of rectangular shape, there is a tendency for the existence of greater temperature differentials in the glass and hence greater differentials in the viscosity of the glass lengthwise of the feeder than in transverse directions. Any variations in the viscosity of the glass in the feeder modify the characteristics of the stream flowing through the orificed tips in the feeder floor resulting in variations in the sizes of filaments attenuated from the streams.

By flowing streams of the respective groups from groups of orifices arranged in lengthwise parallel relation in the feeder floor 14, the average variation in size or coefiicient of variation of the filaments in each of the groups is substantially reduced through this method of grouping of streams from which the groups of filaments are formed. Thus while filament sizes in the respective groups may vary, substantially the same differentials in size of filaments occur in each group with the result that more uniformity or stability of yardage is obtained in the respective strands formed from the groups of filaments.

A thermocouple (not shown) may be connected to a central region of the feeder as indicated by connections 7%) for indicating variations in the temperature of the glass in the feeder.

With particular reference to FIGURE 3, it should be noted that the transverse spacing between lengthwise rows of orificed tips 15 and the transverse spacing between lengthwise rows of the orificed tips 16 is less than the space between the

innermost rows

15 and 16 at the opposite sides of the median plane AA. This arrangement provides an effective spacial division between the groups lengthwise of the feeder to foster more uniform fiow of the glass through the respective groups of streams and facilitate initially threading the respective groups of filaments to the gathering means and onto the strand collector.

FIGURE 4 is a schematic illustration of the prior standard method of forming dual strands of filaments from groups of orifices in a feeder 80. In this prior method, one group of orificed tips 82 from which flow streams attenuated to form one group of filaments 84 is arranged at an area of approximately one half of the feeder fioor at one side of a transverse median plane BB through the feeder, while the other group of orificed tips 86 from which streams are attenuated to form a second group of filaments 88 is arranged at the other side of the transverse median plane BB.

In such method of multifilament dual strand formation, temperature differentials lengthwise of the feeder resulted in the average size of filaments of the group 84 being different from the average size of filaments in the group 88.

This resulted in a substantial over-all ditference in sizes of the strands formed therefrom and hence substantial differentials in the yardage of the

respective strands

90 and 92.

While in FIGURES 1 and 2 the dual strands have been illustrated as being wound upon a collecting surface or surfaces mounted upon a single arbor 22, it is to be understood that the

strands

24 and 28 may be wound on individual collectors driven by individual means. It will be noted from FIGURE 3 that there is illustrated two groups of orificed tips, each group comprising four transversely spaced longitudinally extending rows of orificed tips, but it is to be understood that the number of orifices or orificed tips and hence the number of filaments formed in each strand may be varied dependent upon the number of filaments desired in each strand.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than as herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

I claim:

1. The method of reducing yardage variations between strands of continuous filaments wherein the filaments are of substantially uniform size attenuated from groups of streams of glass including flowing a first group of streams from a group of a plurality of parallel rows of orifices in an elongated feeder arranged lengthwise of the feeder, flowing a second group of streams from a group of a plurality of parallel rows of orifices in the feeder arranged lengthwise of the elongated feeder wherein the orifices of both groups are of substantially the same size and the rows of orifices of the individual groups being in closely adjacent relation to minimize temperature differentials of the glass of the streams flowing from the feeder, the space between the groups of rows being slightly greater than the space between adjacent parallel rows of orifices of the groups, converging the filaments formed from the first group of streams into a strand, converging the filaments formed from the second group of streams into a second strand, and concomitantly attenuating the filaments formed from the groups of streams by simultaneously winding each strand on a separate collector with the groups of filaments moving in side-by-side relation prior to their region of convergence whereby to simultaneously form wound packages of strands having the same yardage in each package.

2. Apparatus for forming continuous filaments from heat-softened mineral material including, in combination, a feeder adapted to contain a supply of the heat-softened mineral material, said feeder being of elongated rectangular shape and having a bottom wall provided with groups of rows of depending projections, the said projections being formed with orifices of substantially uniform size through which flow streams of the material, each group comprising a plurality of rows of the depending projections extending lengthwise of the feeder wherein the rows of the groups are arranged in closely adjacent relation whereby to minimize temperature differentials in the mineral material of the streams, said groups of rows of projections being disposed at each side of a median plane lengthwise of the feeder, the transverse distance between the innermost rows of each group being slightly greater than the transverse distance between adjacent rows of projections of each group, a pair of rotatable collecting surfaces upon which strands of filaments formed from the respective groups of streams are simultaneously wound to attenuate the streams to filaments whereby to form two packages of strands having the same yardage in each package, guide means individual to each group of filaments for converging each group of filaments into a strand wherein the converging filaments of the groups are arranged in overlapping relation transversely of the feeder, and a pair of filament coating applicators arranged in spaced relation lengthwise of the feeder and adapted to be engaged respectively by the individual filaments of each group prior to their convergence into strands whereby each filament receives a coating of material.

References Cited in the file of this patent UNITED STATES PATENTS 2,373,078 Kleist Apr. 3, 1945 2,377,772 Fletcher et a1. June 5, 1945 2,383,168 Slayter Aug 21, 1945 2,386,158 Collins Oct. 2, 1945 2,664,375 Slayter Dec. 29, 1953 2,723,215 Biefeld et a1. Nov. 8, 1955 2,875,503 Frickert et al. Mar. 3, 1959 2,915,806 Grant Dec. 8, 1959

Claims

2. APPARATUS FOR FORMING CONTINUOUS FILAMENTS FROM HEAT-SOFTENED MINERAL MATERIAL INCLUDING, IN COMBINATION, A FEEDER ADAPTED TO CONTAIN A SUPPLY OF THE HEAT-SOFTENED MINERAL MATERIAL, SAID FEEDER BEING OF ELONGATED RECTANGULAR SHAPE AND HAVING A BOTTOM WALL PROVIDED WITH GROUPS OF ROWS OF DEPENDING PROJECTIONS, THE SAID PROJECTIONS BEING FORMED WITH ORIFICES OF SUBSTANTIALLY UNIFORM SIZE THROUGH WHICH FLOW STREAMS OF THE MATERIAL, EACH GROUP COMPRISING A PLURALITY OF ROWS OF THE DEPENDING PROJECTIONS EXTENDING LENGTHWISE OF THE FEEDER WHEREIN THE ROWS OF THE GROUPS ARE ARRANGED IN CLOSELY ADJACENT RELATION WHEREBY TO MINIMIZE TEMPERATURE DIFFERENTIALS IN THE MINERAL MATERIAL OF THE STREAMS, SAID GROUPS OF ROWS OF PROJECTIONS BEING DISPOSED AT EACH SIDE OF A MEDIAN PLANE LENGTHWISE OF THE FEEDER, THE TRANSVERSE DISTANCE BETWEEN THE INNERMOST ROWS OF EACH GROUP BEING SLIGHTLY GREATER THAN THE TRANSVERSE DISTANCE BETWEEN ADJACENT ROWS OF PROJECTIONS OF EACH GROUP, A PAIR OF ROTATABLE COLLECTING SURFACES UPON WHICH STRANDS OF FILAMENTS FORMED FROM THE RESPECTIVE GROUPS OF STREAMS ARE SIMULTANEOUSLY WOUND TO ATTENUATE THE STREAMS TO FILAMENTS WHEREBY TO FORM TWO PACKAGES OF STRANDS HAVING THE SAME YARDAGE IN EACH PACKAGE, GUIDE MEANS INDIVIDUAL TO EACH GROUPS OF FILAMENTS FOR CONVERGING EACH GROUP OF FILAMENTS INTO A STRAND WHEREIN THE CONVERGING FILAMENTS OF THE GROUPS ARE ARRANGED IN OVERLAPPING RELATION TRANSVERSELY OF THE FEEDER, AND A PAIR OF FILAMENT COATING APPLICATORS ARRANGED IN SPACED RELATION LENGTHWISE OF THE FEEDER AND ADAPTED TO BE ENGAGED RESPECTIVELY BY THE INDIVIDUAL FILAMENTS OF EACH GROUP PRIOR TO THEIR CONVERGENCE INTO STRANDS WHEREBY EACH FILAMENT RECEIVES A COATING OF MATERIAL.