US2729028A

US2729028A - Method and apparatus for simultaneously attenuating and severing glass fibers

Info

Publication number: US2729028A
Authority: US
Inventors: Slayter Games; Fletcher Ed
Original assignee: Owens Corning Fiberglas Corp
Current assignee: Owens Corning
Priority date: 1950-11-22
Filing date: 1950-11-22
Publication date: 1956-01-03
Anticipated expiration: 1973-01-03
Also published as: US2719336A; DE869113C; NL85567C; FR1051216A; GB734189A; BE505323A

Description

1956 G- SLAYTER ETAL METHOD AND APPARATUS FOR SIMULTANEOUSLY ATTENUATING AND SEVERING GLASS FIBERS Filed Nov. 22, 1950 2 Sheets-Sheet 1 311 ventor5: FAML'E' SLAY'T'EH 8 .ED FLETCHER.

Gttorueg Jan. 3, 1956 e. SLAYTER EI'AL METHOD AND APPARATUS FOR SIMULTANEOUSLY ATTENUATING AND SEVERING GLASS FIBERS Filed Nov. 22, 1950 2 Sheets-Sheet 2 fay M Zmnentors: FAMEE ELAYTER,

E17 FLE TUHER.

AM AVAVA A A mn nvnvt I O k 7 I (Kttomeg ITZI'7 United States Patent Games Slayter and Ed Fletcher, Newark, Ohio, assignors to Owens-Coming Fiberglas Corporation, Toledo, Ohio, a corporation of Delaware Application November 22, 1950, Serial No. 197,142

16 Claims. (Cl. 49-47) This invention relates to method and apparatus for processing fibers of thermoplastic materials, especially mineral substances and more particularly glass and includes a process also comprising the forming and attenuation of such fibers.

Mineral fibers and especially fine fibers formed of glass in strand or linear configuration have been found to have particular utility when reduced to comparatively short lengths in producing bonded fibrous mats and for forming preforms for use as reinforcement in articles or products molded of plastic or'synthetic resinous materials, asphaltic compounds, natural or synthetic rubber, and mineral materials such as gypsum. Production of short length strands and fibers usually involves the utilization of continuous fibers or strands of fibers which are subsequently reduced to short lengths by additional processing operations.

The production of short length strands, partially opened strands and separate or discrete fibers by controlled means whereby the strand or fiber form best suited for a particular purpose obtainable by simple and inexpensive equipment has long been sought. Various methods have been proposed and tried but they have involved numerous and costly operations and repeated handling of materials and the end results have not been entirely satisfactory or commercially adaptable because of the high cost of production.

Several methods heretofore employed involve the preformation of continuous strands of fibers, and numerous difficulties have been encountered and expensive equip ment required to successfully carry on this phase or step in the ultimate production of short length strands and fibers. One method employed in producing continuous strands is to flow streams of fiber-forming mineral material as for example molten glass from a bushing, attenuating the streams into continuous fibers, gathering the fibers into a strand, applying a binder or adhesive material to the strand and collectingthe strand in cylindrical formation by a so-called cap winder method.

A factor that has impaired the successful attenuation of fine glass fibers by means of pull rolls is that at the high speeds necessary in present-day commercial operations, individual or straggling fibers resulting from fiber breakage and fibers that are not securely bonded in the strand tend to lick" or adhere to and become wound upon the pull rolls resulting in frequent interruption of the process. Such interruptions in the formation of glass fibers are costly as considerable time is required after a stoppage to again attain normal operating conditions of fiber attenuation.

Continuous strands of fibers have been formed by winding a strand at high speed into package or spool formation, the high linear winding speed serving to attenu ate the streams of molten material into fibers. The fibrous strands are reduced or severed to comparatively short lengths in further processing operations, and by various methods the short length strands are partially 2,729,028 Patented Jan. 3, 1956 opened to result in subdivided strand lengths embodying fewer fibers and separated or discrete fibers.

One method employed for this purpose involves splitting the strand package lengthwise, spreading the split packaged strand upon a conveyor and feeding the strand bulk into a spiral cutter or chopper to produce short lengths. This method has not been entirely satisfactory for several reasons. Due to the fact that the strands of the split package are not always conveyed into the spiral cutter or chopper in a direction normal thereto, the resulting severed strands are not of uniform length.

During the formation of the strand, it is impregnated with an adhesive or binder. As the strand is immediately wound into spool or package formation, the winding usually taking place at high linear speeds upwards of several thousand feet per minute, the adhesive or hinder does not have sufficient time to set or harden completely before the strand is wound into package form. Thus the adhesive on the interior convolutions of adhesive-bearing strand in the spool or package may be tacky so that the short length strands emerging from the chopping machine embody or are formed into a mass of tangled clumps and cohering groups of strands Wholly unsuitable for further processing.

One of the advantages of mineral or glass fibers utilized in strand formation lies in the individual strength characteristics of a fibrous strand, but if tangled groups or clumps of strands are prevalent in the assembly, the concentrated groups or clumps of strands result in n0nuniform strength characteristics in the resulting product. Moreover, a mat or other product made of such a mixture is uneconomical because of the excess of glass strands in concentrated groups or clumps. In order to separate the tangled clumps and cohering strands, the mass is subjected to the action of mechanical pickers or separating devices but such operations are expensive and have not been entirely satisfactory because of lack of control over the extent of strand separation and strand clump disintegration so as to secure a satisfactory assembly of intact cut strands, partially opened strands and discrete fibers that is commercially acceptable.

The present invention overcomes these difiiculties and embraces an improved method and the utilization of simple yet effective apparatus for attenuating mineral fibers, gathering them in strand formation and reducing the strand so formed to severed lengths, these operations being effected concomitantly.

An object of the invention resides in the provision of a method whereby continuous mineral fibers in strand or linear formation are attenuated by pull rolls of a character embodyingv a fiber severing means whereby the fibers passing between the pull rolls are severed to predetermined controlled lengths in a manner eliminating any tangled clumps oi cohering strand sections.

Another object of the invention resides in a method and apparatus for concomitantly attenuating and reducing continuous strands to predetermined comparatively short lengths wherein all tendency of any isolated or insecurely bonded fibers to lick or adhere to the pull rolls is com pletely eliminated.

' Another object of the invention resides in the provision of resilient strand-engaging, fiber-attenuating surfaces incorporating fiber severing means co-ordinated with the surfaces in a manner whereby a continuous linear group of fibers is at all times engaged by and under the control of the resilient surfaces in such a manner that an attenuating tension is constantly applied to the fibers being formed in an attenuating zone.

A further object is the provision of an instrumentaiity for concomitantly attenuating fibers of a strand and severing the strand into predetermined lengths whereby the fibers may be attenuated and the strands severed at high 3 linear speeds upwards of several thousand feet per minute whereby the production of severed strands and fibers is rendered economicai for commercial purposes I Ariothcr object of the invention resides in the provision of an apparatus for concomitantly attenuatingand severing fibers whereby through the application of an adhesive or binder to the strand and a regulation of the character and amount thereof applied to the strand, an elfective control is provided over the ratio of opened or partially opened severed strands and individual or discrete fibers emanating fromthe strand severing zone.

A further object of the invention resides in the pro vision of a combinedfiber attenuating and severing device which is operative to sever a linear. group or sliver of fibers in which little or no binderw or. adhesive is applied whereby a massof substantially discrete-or separated cut fibers may be produced if desired.

A further object of the invention is the provision of fiber attenuating means including deformable surfaces arranged for substantial area of contact with the fibers whereby slippage between the deformable surfaces and the fibers is rendered inappreciable or entirely eliminated. Another object of the invention resides in the provision of an inst-rumentality for attenuating glass fibers embody ing a deformable surface whereby substantial linear contact or engagement of the surface with the fibers is constantly maintained.

Another object of the invention resides in the provision of a strand conveying or severing apparatus eliminating extraneous feed rolls.

The invention embraces the provision of method and apparatus especially adaptable for producing bonded mat of strands or fibers of predetermined comparatively short lengths wherein substantially uniform distribution of short length strands and fibers is obtained throughout the mat to provide substantially uniform strength characteristics therein.

Another feature of the invention involves the establishment of forces operable adjacent the fiber attenuating and severing means to alter the normal path of traverse of the severed strands and fibers. whereby a more uniform distribution thereof in a mat or inass formation may be obtained.

Another object of the invention includes the utilization of blasts of gas effectively directed against the cut strands for facilitating and controlling the separation or partial disintegration of the cut strands into partially opened strands and discrete or separated fibers.

Another object resides in the provision. of simple, yet effective apparatus for attenuating and reducing a strand of fibers into short lengths and concomitantly directing blasts of gas against the reduced Strands to alter their direction of travel away from the strand reducing zone.

Another object is the provision of a method and apparatus for producing staple slivers or yarns from severed lengths of attenuated fibers formed of thermoflowable materials such as glass, synthetic resins, plastics or like substances in which blasts of air are employed to facilitate homogeneous distribution and orientation of the severed fibers in a manner particularly suited to the production of staple slivers r yarns wherein the fibers thereof lie in untwisted and nonparallel relation.

Still another object is the provision of a sliver or yarn formed of cut fibers. in which the fibers of the sliver or yarn lie in untwisted, nonparallel relation adapted for use in the manufacture of textiles or for various other uses.

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 struc ture, to various details of construction and to combinations of parts, elements per se, and to economics of manufacture and numerous other features as will be apparent from a consideration of the specification and drawings of a form of'th'einvention, which maybe preferred, in which:

Figure 1 is a semidiagrammatic view illustrating apparatus for carrying out the method of attenuating and severing fibers as utilized in producing bonded mats from the severed fibers;

Figure 2 is an elevational view illustrating the fiber attenuating and severing instrumentality of the invention.

Figure 3 is a plan view of the construction shown in Figure 2;

Figure 4 is a fragmentary view partly in section illustrating a portion of one of the fiber attenuating and severing devices;

Figure 5 is a fragmentary detail sectional view illustrating the character of engagement of the attenuating members with a linear group of fibers;

Figure 6 is a semidiagrammatic view similar to Figure 1 illustrating a modified form of apparatus embodying the use of air blasts for fiber distribution in producing bonded that from the severed fibers, and

Figure 7 is a semidiagrammatic view illustrating apparatus for utilizing the method in forming staple slivers or yarns from out fibers.

The method and apparatus of the present invention is especially adapted for forming and processing glass fibers but the invention is susceptible for use in producing or processing fibers formed of other materials such as thermoplastic fiber forming resins. The arrangement has particular utility in attenuating fibers which are preferably assembled or directed into a strand or linear group, the fibers being continuous so that the strand or group of fibers is of substantially uniform character as there is little or no variation in fiber size when optimum conditions of fiber formation are attained.

Referring to the drawings and initially to Figure 1, there is illustrated an arrangement for carrying out the method of the invention. A suitable receptacle 10 adapted to contain a supply of fiowable or molten film-forming material such as glass is suitably heated by electrical means or other heating medium, and disposed beneath the receptacle 10 is a feeder bushing 12 provided with a comparatively large number of small openings or apertures through which flow streams of the fiber forming material. The streams are attenuated into fine fibers 14 by means of attenuating instrumentalities or rolls 17 and 18. It is desirable that the fibers be gathered into a linear or strand formation S prior to their engagement with the attenuating rolls and hence a gathering member or roll 20 is provided for the purpose.

The present invention has particular utility in the production of lengths of strands or discrete fibers which are adaptable for many and various uses and purposes. For example, the apparatus is. readily adaptable to pro duce unopened or intact strands of short lengths in which the lengths may be varied depending upon the spacing of strand severing means, or the strand or linear group of fibers may be treated in a manner prior to severing same into short lengths whereby opened or subdivided short length strands or strands having fewer fibers may be obtained or discrete or separated fibers may be produced. The extent of the opening up or subdivision of the severed strands or the production of discrete fibers may be controlled by varying the treatment of the fibers or strand prior to the severing operation.

If itis desired to attain substantially unopened or intact severed strands, a suitable adhesive or binding agent having a high mass integrity factor may be applied so as to secure substantial intercohesion of the fibers. If the severed strands are to be separated or subdivided into strands having fewer fibers, then an adhesive .or cohesive agent may be used which does not have a high fiber integrity factor, or the amount of the cohesive or binding agent may be reduced to accomplish this purpose.

if it is desired to obtain severed fibers in discrete or separated form, a nonbinding material such as water or light oil, primarily for lubricating purposes, may be ap- .5 plied to, the fibers. The water or light oil provides a low degree of temporary fiber adhesion which maybe disrupted or rendered ineffective after the engagement of the fibers with the attenuating and severing instrumentality. It has been found that water emulsified with a vegetable oil, as for example, coconut or peanut oils, may be utilized to advantage. Cationic active materials such as amine compounds have been found economical and satisfactory for fiber lubrication purposes when the use of binder is dispensed with. If higher strand cohesion or integrity is desired, binding materials such as starch, gelatin, gum, resin or the like may be used.

Lubricant, adhesive or binding material may be applied in any suitable manner, but may be dispensed to the fibers through the application of the material to the fiber gathering member or roll 20. As illustrated in Figure 1 a receptacle 22, containing a supply of material for treating the fibers or strand, is provided with a discharge tube 23 for directing the treating material to the roll 20, a valve 24 being associated with the tube 23 to control the flow or discharge of material from the container 22.

The fiber attenuating and conveying means of the present invention is inclusive of the rolls 17 and 18 which may be arranged in a manner illustrated inFigures 1 through 3. The rolls 17 and 18 are of similar construction and each may include a pair of disc-

like members

25 and 26 illustrated in Figures 2, 3 and-4. The pairs of

members

25 and 26 together form rotor structures, one being mounted upon a shaft 30, the other being mounted on a shaft 38. The attenuating instrumentalities are provided with resilient or deformable fiber engaging surfaces attained through the utilization of

annular members

32 and 33 formed of rubber, synthetic rubber, molded cork or the like. In the embodiment illustrated, an annular metal ring or band 35 is secured between each pair of

members

25 and 26, a rubber or resilient ring being bonded to each of the metal bands 35 by conventional means.

The shaft 30 carrying the attenuating roll 17 is mounted in suitable bearings 36 carried by a supporting frame 37. The attenuating roll 18 is fixedly secured upon a shaft 38 mounted in bearings 39 carried by the frame 37. Any suitable means may be utilized for rotating the attenuating instrumentalities or rolls as for example a pulley 40 may be mounted upon shaft 38 connected to a motor (not shown) by means of a belt 41.

In certain installations where the rolls operate at comparatively low attenuating speeds, the frictional engage ment of the deformable surfaces of the rolls may be utilized to drive one roll from the other. When a drive of this character is employed, it is imperative to secure proper frictional engagement, and for this purpose the bearings 39 may be supported on adjustable plates 47 formed with elongated slots to accommodate securing bolts 49 for changing the relative position of the attenuating roll 18 toward or away from the roll 17 and retaining the plates 47 and associated elements in adjusted position.

To facilitate satisfactory high speed operation how ever, it has been found preferable to provide for positive driving means between the rolls 17 and 18 so as to assure simultaneous operation without slippage. Any form of positive drive may be employed, as for example, intermeshing gears 44 and mounted respectively on shafts 30 and 38. Through such an arrangement, the resilient

annular members

32 and 33 are relieved of driving stresses. A driving means for the rolls independent of the frictional engagement of the resilient surfaces is desirable as the rapid continuous deformation and flexure of the resilient members at their areas of engagement generates heat. If the frictional engagement is utilized as a driving connection, additional stresses are set up increasing the amount of friction heat which may impair the efliciency of operation at high speeds through heat deterioration of the resilient or rubber fiber-engaging

members

32 and 33. 1

One 'or both of the attenuating rolls may be provided with strand severing instrumentalities or knives for severing the fibers or strand of fibers into short lengths, the linear dimension of the severed fibers being determined by the linear peripheral distance between adjacent knives. In the embodiment illustrated the attenuating roll 17 is provided with one or more strand severing knives 50, there being three shown in Figure 2 which are spaced about the periphery of the roll. In the embodiment illustrated each of the severing instrumentalities or knives 50 extends into awell or recess formed in the annular resilient rubber ring 32, each severing knife being anchored by suitable means 52 in the manner shown in Figure 4.

As illustrated the strand or fiber severing knives or instrumentalities project radially of the axis of rotation of the attenuating member or roll so as to impinge upon and sever the strand or linear group of fibers S passing between the attenuating members 17 and 18. The lengths of the severed strands or fibers is determined by the peripheral distance between adjacent knives when they are carried by a single attenuating roll and if both rolls are provided with strand severing knives the linear distance between one knife on one roll and the next succeeding knife on the other roll determines the severed strand or fiber length.

It should be noted that the deformable or resilient surfaces or surface portions of the attenuating means provided by the resilient rubber rings 32 and 33 are engaged in a manner whereby a substantial rectilinear area of contact is obtained so that the strand S is gripped between the rolls for a substantial rectilinear distance as exemplified in Figure 5. This is an impo1tant factor in attaining successful strand gripping and fiber attenuation through the utilization of the method and apparatus of the invention as the strand is severed when the strand severing knife is in the central zone of the deformed area of the attenuating or strand gripping surfaces. Thus the rectilinear area between the deformed portions of the rubber rings above the strand severing knife must be of sufiicient dimension to securely grip the end of the continuous strand so as to continuously convey or advance the strand through the attenuating rolls. In this manner the fibers are attenuated directly by the rolls from the streams of flowable fiberforming material and are simultaneously severed to desired lengths without intermediate steps or additional operations. This method and apparatus effects extensive savings in production of severed strands or fibers through the elimination of hand labor and handling and transportation involved in other processes for attaining short length strands and fibers.

Due to the fact that the strand is severed at least once during every revolution of the strand severing-attenuating roll 17 such action practically eliminates so-called licking or the tendency of broken discrete or straggling fibers incompletely bound in the strand or group to adhere to the attenuating rolls. Thus if one or more fibers adhere or cling to the roll 18 such adherence is temporary as subsequent severing impact of one of the knives will sever the adhered fiber or fibers and thereby prevent accumulation on the rolls. If both rolls are equipped with severing devices, no licking or adherence of fibers will occur.

The arrangement of Figure l is illustrative of one use for the cut strands or fibers. The severed strands S from the severing Zone are collected upon a suitable surface or conveyor 60 preferably foraminous in character and associated with a suction chamber 61 which is connected with a blower or suction producing means (not shown) which establishes a zone of subatmospheric pressure beneath the surface 60 to facilitate collection of the cut fibers or strands into a mat or mass of predetermined configuration.

The surface 60 may be in the form of an endless conveyor mounted on rollers 64. The collected mass or mat M of fibers may be treated or impregnated with a suitable binding agent as for example phenol formaldehyde dispensed from one or more applicators 65. The fiber collecting and conveying surface 60 may be arranged to advance the mat of fibers through an oven 66 or other suitable apparatus for setting or curing the binder in the mat of fibers to establish mass integrity thereof. The finished mat may be wrapped upon itself in roll configuration 67 or cut to predetermined lengths depending upon the ultimate purpose of use.

The invention is inclusive of means associated with the fiber attenuating and severing instrumentalities for setting up differential forces or zones of pressure for in fiuencing the movement of the cut strands or fibers in carrying on further processing operations. Figure 6 exemplifies in schematic representation an apparatus especially adaptable for producing bonded mat of short length strands, individual fibers or a mixture of partially opened strands and discrete fibers, the relative proportions of cut strands, subdivided strands or individual fibers being dependent upon the density required for the end product and the purpose for which it is to be used.

As illustrated the streams 14' of fiber-forming material issuing from orifices in the bushing 12 are attenuated into fine continuous fibers by the

rolls

60 and 61. The fibers are gathered into a linear group 62 prior to their engagement with the rolls by means of a guide member The fiber attenuating and severing rolls 60 and 61 in this form of the invention are each formed with an interior chamber 63 adapted to be connected with a source of fluid under pressure as, for example, compressed air through hollow-shafts 65 revolubly supporting the rolls. Both rolls are formed with resilient peripheral surfaces for gripping the linear group of fibers and roll 63 is provided with fiber severing knives or bars 68 in the manner illustrated in Figure 4.

Each of the

rolls

60 and 61 is formed with spaced radially arranged passages 76 in communication with the chambers 63 in the rolls, the outlets of passages 70 forming jets adapted to provide blasts of air or other gaseous fluid under pressure from the chambers 63. Disposed in a position to receive cut fibers from the fiber severing zone is a reticulated surface 7.2 of a conveyor 73 carried upon rollers 74 for continuously conveying the formed mat M away from the fiber collecting zone. A suction chamber 76 is preferably disposed adjacent the fiber receiving surface 72 to facilitate the collection and accumulation of the cut fibers 77 thereon.

A shroud or hood 78 may be employed if desired as an aid in directing the cut fibers to the collecting surface but this may be dispensed with without impairing the functioning of the apparatus. Provision is made for the application of a suitable binder to the mat M to establish mass fixation or integrity in the finished product. The binder may be applied preferably in liquid form from a jet or applicator 80, the binder impregnated mat passing through an oven of the character shown in Figure l for curing the binder. Binders such as phenolformaldehyde, starch, gelatin, resins or the like may be used.

In carrying out the method by means of the apparatus of Figure 6, the streams 14' of glass or other flowable fiber-forming material are attenuated to fine fibers by the attenuating rolls 60 and 61, the fibers being guided there to in a linear group 62 by member 20'. It is usually desirable that the mat contain a large proportion of discrete or individual fibers disposed in haphazard assembly and hence no binder or adhesive is applied to the fibers entering the attenuating rolls. It may be advantageous to use water or water containing a small percentage of vegetable oil or a cationic material applied to the fibers at the guide 20' to minimize the friction or abrasion among the fibers.

As the linear group of fibers is successively cut by the knives 68, the cut fibers are subjected to the blasts of air issuing from the passages 70 which are effective in separating the fibers, and facilitating the distribution of the separated fibers over the collecting surface. The air blasts also serve to direct the fibers in a generally downward direction. The turbulence set up by the air blasts forming zones of differential pressure facilitates the ultimate haphazard orientation of the fibers during accumulation into mat formation to secure a product that is fiutfy and of relatively low density. The mat M is treated with binder from the applicator 8i) and is subsequently cured in a suitable oven.

Figure 7 illustrates an arrangement for producing staple slivers or yarns from cut fibers. In this form the streams 14" of fiber-forming material flowing from the bushing 12' are gathered together in a linear group by a guide member 29'. The group of fibers is directed between the attenuating rolls 60' and 61' of the character employed in the form of the invention shown in Figure 6.

While a number of fiber severing knives may be employed on the roll 60, it is desirable to utilize fibers of substantial length in fabricating staple siivers or yarns and a single knife 68' provides cut fibers of a length equal to the circumference of the roll. The attenuating rolls 60 and 61 are provided with peripheral outlets providing blasts of air directed against the cut fibers during rotation of the rolls which effectively dissect the cut fiber groups into separated fibers and distribute the individual or separated fibers over the fiber collecting surface 72' of a movable conveyor 73'.

In order that the severed groups of cut fibers may be readily broken up under the influence of the air blasts, no binder, adhesive or other material which would angment intcrcohesion of the fibers is applied thereto prior to the severing of the fibers into predetermined lengths.

A suction chamber 76 is disposed adjacent the collecting surface 72 to facilitate the collection of the fibers and to set up a resistance to the withdrawal of the fibers during the formation of slivers or yarns therefrom. The mass of fibers on the collecting surface is advanced by the conveyor 73' toward a funnel shaped guide 86 into which the cut fibers are drawn into a sliver or yarn form by the tension thereon through the winding of the sliver or yarn on a bobbin or spool 87 rotated by a driving roll 88. A traverse 89 of conventional character employed in the textile industry serves to distribute the staple sliver or yarn on the bobbin.

Through this process an untwisted staple sliver or yarn in which the fibers are arranged in nonparallel relation may be continuously and inexpensively formed utilizing a simple apparatus which is reliable in operation requiring a minimum of attention on the part of the operator. If it is desired to augment the intercohesion of the fibers on the surface 72', an adhesive may be sprayed onto the fibrous mass by means of an applicator 9d), the character of the adhesive used being dependent upon the tensile strength factor required in the end product. The air blasts from the outlet 70 also serve to prevent the accumulation of cut fibers upon the peripheries of the attenuating rolls. A shroud or hood of the character shown in Figure 6 may be used in this form of the invention to confine the fibers to a predetermined zone although it is not essential to the operation of the method.

It will be apparent that the method and apparatus of the invention, while of a simple nature, is adaptable for high speed operation whereby cut strands and fibers may be economically produced commercially with a minimum of equipment and supervision and eliminating the disadvantages enconntered in the use of other processes.

We claim:

1. A methodof forming and processing fibers including feeding streams of fiber-forming mineral material from a supply; attenuating the streams to form comparatively fine continuous fibers by directing the fibers into engagement with relatively movable deformable surfaces, and

em e

of reducing the attenuated fibers .into predetermined lengths while they are in engagementwith the deformable surfaces.

2. A method of forming and processing fibers including feeding streams of fiber-forming mineral material from a supply; attenuating the streams to form comparatively fine continuous fibers by directing the fibers between a pair of contacting rotatable deformable surfaces, and of severing the attenuated fibers into predeterminedlengths concomitantly with the attenuation of the fibers.

3. A method of formingand processing a strand of mineral fibers including feeding streams of molten mineral from a supply; attenuating the streams to comparatively fine continuous fibers by directing them into frictional engagement with relatively movable deformable surfaces; and of successively engaging the continuous strand of fibers with an instrumentality for reducing the strand to predetermined relatively short lengths while in engagement with the surfaces.

4. A method of forming and processing linear groups of glass fibers including feeding streams of molten glass from a supply; attenuating the streams to form comparatively fine continuous fibers by directing them into frictional engagement with a pair of relatively movable deformable surfaces; and of successively engaging the continuous linear group of glass fibers with an instrumentality for reducing the linear group to predetermined relatively short lengths as the group moves between the surfaces. H h

5. A method of forming and processing a linear group of fibers including feeding streams of molten fiber-forming material from a supply; attenuating the streams of material to form fine continuous fibers by engaging them with relatively movable deformable surfaces; gathering the fibers into a linear group formation prior to their engagement with the deformable surfaces; applying a fluid material to the fibers of the group for establishing fiber intercohesion, and severing the linear group of fibers into predetermined short lengths as it moves between the deformable surfaces.

6. A method of forming and processing strands of fibers including feeding streams of molten fiber-forming material from a supply; attenuating the streams of material to form fine continuous fibers by engaging them with relatively movable deformable surfaces; gathering the fibers into strand formation prior to their engagement with the deformable surfaces; applying a material to the strand for establishing fiber intercohesion; severing the strand of fibers into predetermined short lengths while it is in engagement With the deformable surfaces; and of controlling the extent of separation of the severed lengths into strands of fewer fibers and discrete fibers by varying the character of fiber interoohesion in the strand.

7. A method of forming and processing strands of fibers including feeding streams of molten fiber forming material from a supply; attenuating the streams of material to form fine continuous fibers by engaging them with a pair of relatively rotatable contacting deformable surfaces; gathering the fibers into strand formation prior to their engagement with the deformable surfaces; applying a material to the strand for establishing fiber intercohesion; severing the strand of fibers into predetermined short lengths as it moves between the rotatable deformable surfaces; and of controlling the extent of separation of the severed lengths into strands of fewer fibers and discrete fibers by varying the effectiveness of fiber intercohesion in the strand.

8. A method of forming and processing attenuated fibers formed of glass including flowing streams of molten glass from a supply to form fibers of glass; positioning a pair of surfaces at least one of which is resiliently deformable with their adjacent contacting portions tightly compressed together to present substantial area of contact; directing the fibers as a group into said area of contact; moving said surfaces to advance the group of fibers linearly and concomitantly to'attenuate the fibers; and engaging the linear group of fibers'while they are in said area of contact to sever the same into predetermined lengths, the severing operation being effected in a zone of the area of contact so that the continuous linear group of fibers is constantly in frictional engagement with the surfaces whereby continuous fiber attenuation is obtained unaffected by the fiber severing operation.

9. Apparatus for attenuating and processing continuous fibers including, in combination, means for feeding streams of flowable fiber-forming mineral material; means for attenuating the streams to comparatively fine fibers including a pair of relatively movable surfaces at least one of which is resiliently deformable; said surfaces being engaged whereby adjacent contacting portions thereof are deformed to present substantial area of contact; means for gathering the fibers into linear group formation and directing the group between the surfaces in the area of contact, means for moving the surfaces to attenuate the streams into fibers; means associated with said surfaces engageable with the group of fibers while in said area of contact for reducing the linear group to predetermined lengths, said fiber reducing operation being efiective in a zone of said area of contact so that the continuous linear group is constantly in frictional engagement with said surfaces whereby continuous fiber attenuation is obtained unalfected by the fiber reducing operation.

10. Apparatus for attenuating and processing continuous fibers including, in combination, means for feeding streams of fiowable fiber-forming mineral material; means for attenuating the streams to comparatively fine fibers including a pair of resilient rotatable surfaces; said sur faces being disposed in engagement whereby adjacent contacting portions thereof are deformed to present substantial area of contact; means for gathering the fibers into linear group formation and directing the group between the resilient surfaces in the area of contact, means for rotating the surfaces to attenuate the streams into fibers; means associated with one of said surfaces engageable with the linear group of fibers while in said area of contact for severing the linear group of fibers to predetermined lengths, said fiber severing operation being effective in a zone of said area of contact so that the continuous group of fibers is constantly in frictional engagenient with said surfaces whereby continuous fiber attenuation is obtained unaffected by the severing operation.

11. A method of forming and processing fibers including feeding streams of fiber-forming material from a supply; attenuating the streams to comparatively fine continuous fibers by directing them into engagement with a pair of relatively movable deformable surfaces; of successively engaging the fibers with an instrumentality for reducing the fibers to predetermined relatively short lengths while in engagement with the surface, and of directing blasts of gas against the short length fibers to distribute them over a substantial area.

12. A method of processing fibers including directing a linear group of continuous fibers into engagement with relatively movable deformable surfaces; of moving the surfaces to advance the group of fibers; of successively severing the linear group of fibers into predetermined lengths while the group is in engagement with the surfaces, and of establishing zones of differential pressure for entraining and distributing the severed fibers as they are discharged from engagement with the surfaces.

13. The method of processing fibers including directing a linear group of continuous fibers into engagement with continuously rotating deformable surfaces; of severing the group of fibers into predetermined lengths in the zone of engagement of the surfaces with the group, and of entraining the severed fibers in blasts of air emanating from outlets formed in the surfaces and conveying them away from the surfaces.

14. Apparatus for processing a linear group of continuous fibers including, in combination, a pair of relatively movable members having deformable fiber-engaging surfaces, said surfaces being in contacting relation whereby a rectilinear contact of substantial area is established for frictionally engaging the linear group of fibers passing through the area. of contact; means for moving said surfaces to advance the group of fibers in a linear direction, means associated with one of the members for successively severing the continuous linear group of fibers into predetermined lengths while the group of fibers is in the area of rectilinear contact of the members; said surfaces being formed with outlets arranged to discharge blasts of gas against said severed fibers.

15, Apparatus for processing a linear group offibers including, in combination, a pair of rotatable members having engaging resilient surfaces; said engaging surfaces being adapted to frictionally contact and advance the linear group of fibers; a fiber severing instrumentality car.- ried by one of said members arranged to sever the g oup of fibers to predetermined lengths during rotation of said members; said members being formed with chambers adapted to contain gas under pressure, and outlets formed in said members for discharging blasts of gas in the zone of discharge of the severed fibers from the rotatable members.

16. A method of forming and processing attenuated fibers formed of glass including flowing streams of molten glass from a supply to form fibers, rotating a pair of circular surfaces at least. one of which surfaces is compressible upon parallel axes so spaced that said surfaces contact each other over a substantial area of contact; associating said fibers into a. group; directing said fibers as a group into said. area of contact between said surfaces; rotating said surfaces to advance the group of fibers linearly and concomitantly to attenuate the fibers; and engaging the group of fibers while. they are in said area of contact for severing the same into predetermined lengths, whereby during severing said group of fibers is frictionally engaged between said surfaces in said area of contact adjacent to and on both sides of the line of severing and continuous fiber attenuation is obtained unaffected by the fiber severing operation.

References Cited in, the, file of this patent UNITED STATES PATENTS

Claims

9. APPARATUS FOR ATTENUATING AND PROCESSING CONTINUOUS FIBERS INCLUDING, IN COMBINATION, MEANS FOR FEEDING STREAMS OF FLOWABLE FIBER-FORMING MINERAL MATERIAL; MEANS FOR ATTENUATING THE STREAMS TO COMPARATIVELY FINE FIBERS INCLUDING A PAIR OF RELATIVELY MOVABLE SURFACES AT LEAST ONE OF WHICH IS RESILIENTLY DEFORMABLE; SAID SURFACES BEING ENGAGED WHEREBY ADJACENT CONTACTING PORTIONS THEREOF ARE DEFORMED TO PRESENT SUBSTANTIAL AREA OF CONTACT; MEANS FOR GATHERING THE FIBERS INTO LINEAR GROUP FORMATION AND DIRECTING THE GROUP BETWEEN THE SURFACES IN THE AREA OF CONTACT, MEANS FOR MOVING THE SURFACES TO ATTENUATE THE STREAMS INTO FIBERS; MEANS ASSOCIATED WITH SAID SURFACES ENGAGEABLE WITH THE GROUP OF FIBERS WHILE IN SAID AREA OF CONTACT FOR REDUCING THE LINEAR GROUP TO PREDETERMINED LENGTHS, SAID FIBER REDUCING OPERATION BEING EFFECTIVE IN A ZONE OF SAID AREA OF CONTACT SO THAT THE CONTINUOUS LINEAR GROUP IS CONSTANTLY IN FRICTIONAL ENGAGEMENT WITH SAID SURFACES WHEREBY CONTINUOUS FIBER ATTENUATION IS OBTAINED UNAFFECTED BY THE FIBER REDUCING OPERATION.