US3207587A

US3207587A - Method and apparatus for producing fibers

Info

Publication number: US3207587A
Application number: US91371A
Authority: US
Inventors: Murray E Fulk
Original assignee: Owens Corning Fiberglas Corp
Current assignee: Owens Corning
Priority date: 1961-02-24
Filing date: 1961-02-24
Publication date: 1965-09-21
Anticipated expiration: 1982-09-21

Description

Sept. 21, 1965 M. E. FULK METHOD AND APPARATUS FOR PRODUCING FIBERS Filed Feb. 24. 1961 IN V EN TOR.

MURRAY E. FULK A TTOPNEYS United States Patent 3,207,587 METHOD AND APPARATUS FOR PRODUCING FIBERS Murray E. Fulk, Newark, Ohio, assignor to Owens- Corning Fiherglas Corporation, a corporation of Delaware Filed Feb. 24, 1961, Ser. No. 91,371 11 Claims. (Cl. 65-5) The present invention relates to a method of and apparatus for producing fibers from heat-softenable materials and more especially to the production of fibers by attenuation through the utilization of high velocity gaseous blasts.

Glass fibers have been produced extensively by attenuating streams of glass by engaging the streams with high velocity gaseous blasts, the fibers being employed for mats, batts and the like. In such processes attenuation of the glass streams is attained by directing blasts of steam, compressed air or other gases under pressure from nozzles or orifices of a blower, the blasts of gas being directed at opposite sides of one or more rows of streams. Fibers attenuated by such process have been used to form comparatively thin fibrous mat containing a suitable binder which is cured to hold the fibers in integrated assembly, such product being generally known as a bonded mat.

Recent improvements in the blower arrangement for producing fibers especially employed in fabricating bonded mats have been made wherein a double row of streams are flowed from a stream feeder or bushing and each row of streams engaged by high velocity gaseous blasts wherein the region of engagement of the blasts at the inner sides of the streams are above the regions of engagement of the blasts at the outer sides of the rows of streams, an arrangement which reduces turbulence through a more effective control of the blast induced air streams. While such method improves the efliciency of blast attenuation of fibers and provides a high production yield of fibers in proportion to the energy expended, certain difficulties have been encountered which impair the shape and character of the fibers produced by this method. The pairs of blasts which, through moving in generally parallel relation are slightly convergent and the gases from the elongated orifices or nozzles of the dual blower sections impinge one another at a region a short distance below the blower sections and are abruptly deflected in divergent paths. This sudden change of direction of the gases of the blasts occurs during attenuation while the fibers or filaments are in a plastic state and are readily deformable. As the fibers or filaments being attenuated by the blasts are entrained with the gases of the blasts, the abrupt change in direction of the gases deforms the fibers or filament forming kinks therein. The presence of kinks in the fibers of a bonded mat formed from the fibers is undesirable as the strength of the fibers is impaired and they detract from the appearance of the finished bonded mat.

The present invention embraces a method of controlling the direction of flow of gases of multiple blasts employed for attenuating a plurality of rows of streams of fiberforming material whereby the gases of the blasts and the fibers being attenuated thereby are influenced to travel in rectilinear paths whereby the fibers formed by attenuation are of rectilinear character and are devoid of kinks.

An object of the invention is the provision of a method of controlling the flow of gases of multiple attenuating blasts during attenuating operations on heat softenable mineral materials whereby the tendency for formation of kinks in the attenuated fibers or filaments is substantially reduced or eliminated.

Another object of the invention is the provision of a 3,207,587 Patented Sept. 21, 1965 "ice means associated with a double blower construction ar ranged whereby pairs of blasts from the blower attenuate multiple rows or groups of streams of mineral material to fibers whereby the gases of the blasts are caused to travel in more nearly parallel paths at the attenuating zones whereby attenuation efficiency is improved.

Another object of the invention resides in the provision of a double blower construction from which multiple blasts emanate for attenuating multiple groups of streams of fiber-forming mineral material to fibers in combination with baffle or separator means disposed between pairs of gaseous blasts arranged to prevent or substantially reduce interimpingement or interference of the gases of adjacent blasts whereby to influence or direct the gases of the blasts to move in rectilinear paths throughout the attenuating regions of the blasts.

Another object of the invention resides in a double blower construction provided with a bafile or separator at the central section of the blower whereby the gases of adjacent fiber-attenuating blasts are prevented from interengagement throughout the length of the attenuating zones of the blasts with a consequent elimination or substantial reduction of turbulance occurring or existing at the attenuating zones.

Another object resides in the provision of a transversely arranged baffle means associated with a multiple blast blower construction for reducing the tendency of the gases of the blasts to pile-up at the central regions of the blasts by reason of the effect of the blast induced air streams existent at the end regions of the blower construction whereby more efiicient attenuation is attained.

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 an elevational view of a fiber-forming and fiber collecting apparatus embodying a double blower construction and baflie or separator arrangement for carrying out the method of the invention:

FIGURE 2 is a transverse sectional view taken substantially on the line 22 of FIGURE 1;

FIGURE 3 is an isometric view of a form of double blower construction illustrating the separator or bafile means at the central region of the blower construction, and

FIGURE 4 is a view similar to FIGURE 3 illustrating a transversely arranged bafile or separator means associated with a multiple blast blower.

The method and apparatus of the invention are especially adaptable for use in the attenuation of multiple rows of streams of heat-softened material such as glass to fine fibers through the employment of high velocity gaseous blasts, but it is to be understood that the invention may be utilized for controlling multiple blasts wherever the same may be found to have utility.

The forms of apparatus disclosed herein for carrying out the method are arranged to direct attenuating blasts at opposite sides of multiple rows or groups of streams of fiber-forming materials in a manner whereby the innermost blasts between rows or groups of streams of material are engaged with the streams in advance of the region of engagement of attenuating blasts at the outer sides of rows or groups of streams of material in combination with influencing the paths of traverse of gases of pairs of blasts to prevent engagement of the gases of one pair with the gases of another pair of blasts throughout the attenuating range of the blasts.

Referring to the arrangement disclosed in FIGURES 1 3 through 3 of the drawings, there is illustrated a means such as a forehearth or receptacle adapted to contain a supply of heat-softened fiber-forming material such as glass, the glass being.in molten of flowable condition. The forehearth may be connected with a melting furnace (not shown) in which the glass batch or other mineral material is reduced to a molten or flowable state and flowed from the furnace to the forehearth 10.

The forehearth or receptacle 10 is fashioned of refractory or other material capable of withstanding high temperatures, and is equipped with a stream feeder or bushing 12. The stream feeder 12 is mounted in the floor of the forehearth 10 and is preferably made of an alloy of platinum and rhodium. The feeder 12 is preferably of elongated rectangular shape, the end walls of which may be provided with lugs 14 for connection with conductors of an electric circuit for flowing controlled current through the feeder 12 to maintain the glass in the feeder at the proper temperature and viscosity.

As illustrated particularly in FIGURE 2, the bottom region of the stream feeder 12 is formed with lengthwise arranged trough-

like configurations

16 and 17 each

configuration

16 and 17 being provided with a row of tips or

projections

19 and 20 provided with orifices or passages through which rows or groups of

streams

22 and 24 flow downwardly from the feeder in parallel relation.

A screen 26 is preferably provided extending across the interior of the feeder. 12 for preventing particles of refractory or fragments of unrefined glass from flowing into the feeder to prevent obstruction of the passages in the

projections

19 and 20.

Disposed beneath the feeder 12 is a blower construction 28 formed with elongated passages or

slots

30 and 32 extending lengthwise of the blower through which the rows of streams flow from the feeder. Arranged beneath the feeder 12 is a fiber-forming hood or enclosure 34 providing a forming chamber into which the fibers formed by blast attenuation are delivered by the blasts. Arranged at the lower end of the fiber-forming hood is a fiber collecting means such as an endless belt-type conveyor 36 of foraminous or reticulated character, the upper flight 38 thereof being arranged to move across the end of the chamber 35.

The blast attenuated fibers 40 are collected in a com- 'paratively thin layer upon the advancing upper flight 38 for further processing.

Applicators 44 such as spray nozzles are arranged or adapted to spray or deliver a binder, adhesive or other fiber-coating material onto the fibers as they move through the fiber-forming chamber 35. A receptacle 46 is disposed beneath the upper flight 38 of the foraminous conveyor the receptacle providing a suction chamber 48 in registration with the forming chamber 35.

A pipe 50 joined with the chamber 48 is adapted to be connected with a suction blower or other source of reduced pressure to maintain reduced pressure in chamber 48 to facilitate collection of the fibers upon the conveyor flight 38 and to convey away the spent gases of the attenuating blasts. The blower construction is particularly illustrated in FIGURES 2 and 3 and is especially adapted for directingpairs of high velocity steam blasts into engagement with the

glass streams

22 and 24 for attenuating the glass to fibers, but it is to be understood that compressed air or other gas under pressure may be utilized if desired.

The blower construction 28 is inclusive of a manifold or gas distributor block 52 formed with a threaded extension 54 for connection with a pipe or conduit (not shown) arranged to convey steam or other gas under pressure to the blower. In the embodiment illustrated, the manifold 52 extends transversely from the blower construction and provides distribution chamber 56. Secured to the manifold 52 and disposed above the same are longitudinally-,-

extending substantially-parallel members or plates 58 arranged respectively at the outer sides of the rows of

streams

22 and 24, each of the plates 58 being formed with lengthwise arranged upwardly extending

portions

59 and 60.

A cover plate or blower cap 62 is provided for each of the plates 58 secured thereto by screws 63. The regions defined by each pair of upwardly extending

portions

59 and 60 with the cover plates 62 provide chambers or manifolds 64 which receive steam or other gas from the main manifold 56 through passages or ports 65.

The members or plates 58 and the cover plates 62 are secured to the manifold block 52by screws 68. As shown in FIGURE 2, the blower sections or assemblies provided by the

plates

58 and 62 are disposed at the respective outer sides of the

glass streams

2 and 24.

Disposed between these assemblies is a central blower section comprising a body member 72 extending in parallelism with the plates 62 and formed with upwardly extending walls 74 defining a chamber 76. Disposed above and extending lengthwise of the member 72is a blower cap or cover plate secured to member 72 by screws 82, the cap 80 defining an upper wall of the chamber 76. The member 72 and the blower cap 80 are secured to the manifold 52 by screws 78.

The central chamber 76 receives steam or other gas under pressure from the manifold chamber 56 through a passage or port 79. As particularly shown in FIG- URES 2 and 3, the member 80 extends substantially above the upper planar surfaces of the cover plates or blower caps 62 of the outer blower sections. The cover plates or blower caps 62 and the portions 60 are spaced from the respective side walls 74 of the central section providing the passages or

blower slots

30 and 32 through which the glass streams flow from the feeder 12.

The regions of the caps 62 adjacent the

slots

30 and 32 are formed with depending skirt portions 86 spaced transversely from the portions 60 of members 58 providing passages 8 through which the steam in the chambers 64 is projected at high velocities in the general direction of the streams at the outer sides of the rows of glass streams and into engagement with the streams. The blower cap 80 of the central blower section is formed with depending skirt portions 90 spaced from the upper portions of the walls 74 to form passages or slots 92 through which steam from the chamber 76 is projected at high velocities in a downward direction through the

slots

30 and 32 into engagement with the glass streams.

As shown in FIGURE 2, the blower cap 80 of the central section of the blower construction extends upwardly a substantial distance and terminates in a horizontal plane approximately at the terminus of the

orificed projections

19 and 20 through which the streams of glass flow from the feeder.

For theaverage size blower, it is found that the upper surface of the blower cap 80 is preferably disposed about thirteen thirty-seconds of an inch or more above the plane of the upper surfaces of blower caps 62. This dimension may be modified for use with glass compositions central region of each of the slots.

The member 72 atthe.

Disposed between the member 72 and each pair of

plates

59 and 62 are members or blocks 100. A pair of blocks 100 is arranged at each end of the blower assembly, the blocks of one pair being secured to the manifold member 52 and the blocks of the other pair secured to the transversely extending bar 96. The inner surfaces of the blocks 100 define the ends of the

stream receiving passages

30 and 32.

It will be noted in FIGURE 2 that the surfaces of the blower skirts 86 and the adjacent surfaces of the portions 60 of plates 58 defining the blower passages or slots 88 are arranged at an angle with respect to the vertical flow path of the streams from the feeder such angularity being between about ten and fourteen degrees to direct or converge the gases of the blasts into engagement with the streams of glass.

The inner surfaces of the blower skirts 90 of the central cap member 80 and the adjacent surfaces of walls 74 of member 72 are likewise angularly arranged with respect to the vertical flow path of the streams, the angularity being between approximately ten and fourteen degrees to converge the blasts from the center sections into engagement with the glass streams 22 and 24.

Thus the pair of blasts directed through each of the stream-receiving passages or slots are in converging relation to assure engagement of the gases of the blasts with the streams for attenuating the streams to fibers.

It has been found that, at a region a short distance beneath the blower assembly, the blasts engaging the respective rows of or groups of glass streams tend to converge at a median plane through the central section lengthwise of the blower. The gases of the blasts by their interimpingement are abruptly deflected outwardly and downwardly from the central median plane of the blower assembly. The attenuation of the glass stream to fibers is taking place in this region and as the fibers entrained in the gases of the blasts are still in plastic or deformable condition, the abrupt deflection of the blasts through their interimpingement forms kinks in the fibers under the influence of the outwardly deflected gases of the blasts.

In the average size blower it is found that the zone of interimpingement of the gases of the blasts occurs from three to five inches below the terminae of the stream receiving slots or

passages

30 and 32. The blower arrangement includes means for preventing interimpingement of the gases of the blasts throughout the attenuating region or zone. As illustrated in the drawings, a separator, baflle or deflector 104, which may be fashioned of sheet metal, is disposed lengthwise of the blower assembly and in a vertical plane through the median or central region of the blower assembly.

The sheet metal separator or baffie 104 is provided at its upper end region with a transversely extending flange 106 which accommodates securing screws 108 passing through openings in the flange and extending into threaded bores formed in the central section 72 of the blower. It is found that the separator or bafile 104 should preferably depend from the blower construction a distance of from four to seven inches depending upon the angularity of the blasts and the size of the blower construction.

Through this arrangement the pairs of blasts moving downwardly from the slots or

passages

30 and 32 are prevented or restrained from interimpingement at the attenuating region and the fibers formed by the blasts are rectilinear and devoid of kinks. Furthermore the employment of the baffle means 104 effects a reduction in turbulence at the attenuating region beneath the blower assembly resulting in improved efliciency of attenuation and in the production of longer fine fibers from the glass streams.

The method of operation of the blower and baflle construction as illustrated in the drawings is as follows: Super heated steam under substantial pressure or compressed air is delivered into the manifold chamber 56 from a supply, the steam or other gas moving through the ports 65 and 79 into the outer blower chambers 64 and the chamber 76 formed in the central section 72.

The steam in the chamber 76 is projected through the orifices or passages 92 forming high velocity gaseous blasts directed generally downwardly in slight converging relation as hereinbefore explained into the steam-receiving passages or

slots

30 and 32 and into engagement with the rows of

streams

22 and 24.

Steam from the chamber 64 is projected through the blower slots or orifices 88 forming high velocity gaseous blasts directed downwardly through the

passages

30 and 32 and into engagement with the glass streams of the respective rows. The pairs of gaseous blasts in each passage attenuate these streams moving through the respective passages and draw out or attenuate the streams into fine fibers.

The blower cap being disposed at a higher level or elevated position than the upper surfaces of the blower caps 62 reduces or minimizes the blast-induced air streams and provides an eflective control of the blast-induced air moving into the

passages

30 and 32 across the upper surfaces of the outer blower caps 62. The elevated or raised position of the blower cap 80 of the central section substantially eliminates a region of reduced pressure between the rows of streams.

This means of control of direction of potential flow of the induced air is effective in securing a proper balance of the momentums of the induced air streams.

Furthermore the employment of high velocity gaseous attenuating blasts emanating from blower slots arranged at different levels, as shown in FIGURE 2, provides for a more smooth flow of induced air along the glass streams and, in conjunction with the baffle means or separator 104, attains substantially vertical rectilinear attenuation of the streams throughout the full length of the attenuating region of the blasts.

The induced air stream moving into each slot or

passage

30 and 32 is influenced by the upper blast from the .orifices or blower slots 90 whereby the momentum of the induced air stream moving in a direction across each of the blower plates 62 toward the blower cap 80 is reduced and to a substantial extent is balanced by the downward forces of the blasts bending the streams of induced air into the glass receiving passages or slots. This arrangement reduces laterally acting forces which would otherwise cause whipping or impinging of the fibers against the walls defining the glass

stream receiving passages

30 and 32.

As the blasts from the blower slots 88 are delivered at a region below the region of delivery of the blasts from the blower slots 92 in the central section, the velocity of the outermost blasts influences the induced air to continue to flow more nearly in a rectilinear direction. However as some of the energy of the blasts from the upper slots 92 has been dissipated before the blasts from the lower blower slots 88 are delivered into engagement with the inner blasts, the outermost blasts tend to divert the gases from the upper blasts toward a central median region of the blower construction.

The baffle means or separator 1.04 is effective to deflect or prevent impingement of the gases of the respective pairs of blasts and secure more straight line flow of the gases and hence the formation of kinks in the fibers is substantially eliminated. Such fibers have higher strength characteristics and where the fibers are formed into a comparatively thin bonded mat, the appearance of the mat is greatly improved by the absence of kinks in the fibers.

While the feeder or bushing 12 is illustrated as provided with two lengthwise arranged, spaced rows or orificed projections 19, the feeder 12 may be fashioned with pairs of groups or rows of stream feeding orifices whereby two or more rows of streams are delivered into each of the

passages

30 and 32. In such arrangement, each pair of gaseous blasts engages two or more rows or groups of streams and thereby increasing the yield of fibers.

FIGURE 4is illustrative of a blower construction of the character illustrated in FIGURES 1 through 3 em bodying a transversely extending baflle means 110 preferably formed of sheet metal secured to the members 58' and 72 by screws 112, the baflle means depending from the blower construction. It has been found that where the blower construction is of substantial length, the blastinduced air flowing into the ends of the slots or glass receiving passages 30' and 32' tends to cause a piling up of the gases of the blasts adjacent the central regions lengthwise of the attenuating blasts.

Through the provision of the transversely disposed baflle or separator 110 the tendency for the induced air streams to influence the gases of the blasts to pile-up at the cetnral regions of the blower is substantially reduced. The bafiie or separator 110, in efiect, divides the blower lengthwise into two comparatively short length blowers thereby improving the flow path and attenuating efficiency of the blasts at opposite sides of the transversely arranged bafiie 110 without sacrificing production yield of fibers. The baffle means 110 may be employed in conjunction with the baflie, means 104 or may be used independently of the bafile meanas 104 as illustrated in FIGURE 4. Where both baflie plates or separator means are utilized with the blower, each bafile plate may be slotted through one-half of its width to facilitate interlocking of the plates..

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 forming fibers from heat-softened material by blast attenuation including flowing streams of the material in spaced groups from a supply through walled passages, engaging the material of the streams in each walled passage by a pair of high velocity gaseous blasts discharging at diflierent levels in the passage, and separating the gases of the pairs of blasts by a surface below the passages and midway between the pairs of blasts extending substantially throughout the length of the attenuating region to effect substantially rectilinear attenuation of the streams to fibers.

2.The method of forming fibers from heat-softened material by blast attenuation including flowing streams of the material in spaced groups from a supply through walled passages, engaging the material of the streams in each passage with a first gaseous blast from an orifice in the inner wall of each passage, engaging the material of the streams in each passage with a second gaseous blast discharged from an orifice in the outer wall of each passage at a lower region than the zone of engagement of the first blasts with the material, obstructing the flow of blast-induced air at the region between the passages, and separating pairs of blasts by a surface at a median zone below the passages extending substantially throughout the length of the attenuating region to prevent interference of gases of the blasts and effect substantially rectilinear attenuation of the streams to fibers.

3. The method of forming fibers from heat-softened materials by blast attenuation including flowing streams of the material in spaced groups from a supply through walled passages, engaging the material of the streams in each passage with a first gaseous blast from an orifice in the inner wall of each passage, engaging the material of the streams in each passage with a second gaseous blast discharged from an orifice in the outer wall of each passage at a lower region than the zone of engagement of the first blasts with the material, obstructing the flow of blast-induced air at the region between the passages, and, dividing the attenuating regions below the passages by a surface extending substantially throughout thelength of the attenuating region to prevent interference of gases of the blasts.

4. The method of forming fibers from heat-softened material by blast attenuation including flowing streams of the material in spaced groups from a supply through walled passages, engaging the material of the streams in each passage with a first gaseous blast from an orifice in the inner wall of each passage, engaging the material of the streams in each passage with a second gaseous blast discharged from an orifice in the outer wall of each passage at a lower region than the zone of engagement of the first blasts with the material, obstructing the flow of blast-induced air at the region between the passages, and guiding the gases of the pairs of blasts in. parallel rectilinear directions at a zone below the passages by a median surface substantially throughout the length of the attenuating region to effect substantially rectilinear attenuation of the streams to fibers.

5., Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower, construction'disposed adjacent the stream feeding means formed with a pair of walled passages wherein each passage accommodates a group of streams, the walls of each passage of the blower construction being provided with alongated slots at opposite sides of each group of streams through which gases under pressure are discharged as a pair of high velocity blasts, and a depend.- ing wall disposed beneath the central region of the blower and betweenthe pairs of blasts extending substantially throughout the length of the attenuating region to prevent interference of divergently moving gases of the blasts at the attenuating region thereof.

6. Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent the stream feeding means, said blower construction being. provided with pairs of elongated slots at opposite sides of each group of streams through which gases under pressure are discharged as high velocity blasts, the slots of each pair at different levels, and a baflle member depending from the central region of the blower extending substantially throughout the length of the attenuating region to separate the gases of the pairs of blasts at the attenuating region thereof.

7. Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent the stream feeding means, said blower construction being provided with pairs of elongated slots at opposite sides of each group of streams through which gases under pressure are discharged as high velocity blasts, the blower slots arranged between the groups of streams being at a different level than the blower slots at the outer sides of the groups of streams whereby the blasts of each pair engage the adjacent group of streams at zones spaced lengthwise of the streams to attenuate the streams to fibers, and a vertically disposed baflle plate extending downwardly from the central region of the blower substantially throughout the length of the attenuating region to prevent interference of the gases of the pairs of blasts at the attenuating region thereof.

8. Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent and beneath the stream feeding means, said blower construction being provided with spaced passages to receive respectively the spaced groups of streams of material, said blower be-- ing formed with a chamber between the groups of streams and chambers at the outer sides of the groups of streams,

munication with the chambers through which gas is discharged as pairs of gaseous blasts into each passage and into engagement with the groups of streams to attenuate the material of the streams to fibers, and a vertically arranged bafile plate of planar shape disposed beneath the blower construction between the pairs of blasts and extending downwardly a distance of from four to seven inches for controlling the flow paths of gases of the blasts.

9. Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent and beneath the stream feeding means, said blower construction being provided with spaced passages to receive respectively the spaced groups of streams of material, said blower being formed with a chamber between the groups of streams and chambers at the outer sides of the groups of streams adapted to contain gas under pressure, the walls defining the passages being provided with orifices in communication with the chambers through which gas is discharged as pairs of gaseous blasts into each passage and into engagement with the groups of streams to attenuate the material of the streams to fibers, the orifices in the walls of the chamber between the groups of streams through which gaseous blasts are projected being above the orifices in the walls of the chambers at the outer sides of the groups of streams through which gaseous blasts are projected whereby the pairs of gaseous blasts engage the streams at vertically spaced zones, and a vertically arranged separator plate disposed beneath the blower construction and extending substantially throughout the length of the attenuating region for controlling the flow paths of the gases of the pairs of blasts at the attenuating range of the blasts.

10. Apparauts for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent and beneath the stream feeding means, said blower construction being provided with spaced passages to receive respectively the spaced groups of streams of material, said blower being formed with orifice means arranged to direct multiple gaseous blasts at diiferent levels into each passage and 10 into engagement with the groups of streams to attenuate the material of the streams to fibers, and a vertically arranged plate extending downwardly from the blower construction at a median region between the passages substantially throughout the length of the attenuating region to divide the gases of the blasts.

11. Apparatus for producing fibers from heat-softened material including, in combination, means for feeding spaced groups of streams of the material from a supply, a blower construction disposed adjacent and beneath the stream feeding means, said blower construction being provided with spaced passages to receive respectively the spaced groups of streams of material, said blower being formed with a chamber between the groups of streams and chambers at the outer sides of the groups of streams adapted to contain gas under pressure, the walls defining each of the passages being provided with orifices arranged at different levels in communication with the chambers through which gas is discharged as pairs of gaseous blasts into each passage and into engagement with the groups of streams to attenuate the material of the streams to fibers, a vertically arranged plate disposed beneath and depending from the blower construction and extending lengthwise thereof substantially full length of the attenuating region to prevent impingement of divergently moving gases of one pair of blasts with divergently moving gases of the other pair of blasts.

References Cited by the Examiner UNITED STATES PATENTS 2,206,060 7/40 Slayter 5 2,224,466 12/40 Baker et al. 65-16 2,635,285 4/53 Toulmin 65-7 2,653,416 9/53 Slayter 65--9 2,774,630 12/56 Henry et al. 239433 2,927,621 3/60 Slayter et al. 659 3,021,558 2/62 Roberson 655 FOREIGN PATENTS 1,154,476 4/58 France.

DONALL H. SYLVESTER, Primary Examiner. MICHAEL V. BRINDISI, Examiner.

Claims

2. THE METHOD OF FORMING FIBERS FROM HEAT-SOFTENED MATERIAL BY BLAST ATTENUATION INCLUDING FLOWING STREAMS OF THE MATERIAL IN SPACED GROUPS FROM A SUPPLY THROUGH WALLED PASSAGES, ENGAGING THE MATERIAL OF THE STREAMS IN EACH PASSAGE WITH A FIRST GASEOUS BLAST FROM AN ORIFICE IN THE INNER WALL OF EACH PASSAGE, ENGAGING THE MATERIAL OF THE STREAMS IN EACH PASSAGE WITH A SECOND GASEOUS BLAST DISCHARGED FROM AN ORIFICE IN THE OUTER WALL OF EACH PASSAGE AT A LOWER REGION THAN THE ZONE OF ENGAGEMENT OF THE FIRST BLASTS WITH THE MATERIAL, OBSTRUCTING THE FLOW OF HEAT-INDUCED AIR AT THE REGION BETWEEN THE PASSAGES, AND SEPARATING PAIRS OF BLASTS BY A SURFACE AT A MEDIAN ZONE BELOW THE PASSAGES EXTENDING SUBSTANTIALLY THROUGHOUT THE LENGTH OF THE ATTENUATING REGION TO PREVENT INTERFERENCE OF GASES OF THE BLASTS AND EFFECT SUBSTANTIALLY RECTILINEAR ATTENUATION OF THE STREAMS TO FIBERS.
5. APPARATUS FOR PRODUCING FIBERS FROM HEAT-SOFTENED MATERIAL INCLUDING, IN COMBINATION, MEANS FOR FEEDING SPACED GROUPS OF STREAMS OF THE MATERIAL FROM A SUPPLY, A BLOWER, CONSTRUCTION DISPOSED ADJACENT THE STREAM FEEDING MEANS FORMED WITH A PAIR OF WALLED PASSAGES WHEREIN EACH PASSAGE ACCOMMODATES A GROUP OF STREAMS, THE WALLS OF EACH PASSAGE OF THE BLOWER CONSTRUCTION BEING PROVIDED WITH ALONGATED SLOTS AT OPPOSITE SIDES OF EACH GROUP OF STREAM THROUGH WHICH GASES UNDER PRESSURE ARE DISCHARGED AS A PAIR OF HIGH VELOCITY BLASTS, AND A DEPENDING WALL DISPOSED BENEATH THE CENTRAL REGION OF THE BLOWER AND BETWEEN THE PAIRS OF BLASTS EXTENDING SUBSTANTIALLY THROUGHOUT THE LENGTH OF THE ATTENUATING REGION TO PREVENT INTERFERENCE OF DIVERGENTLY MOVING GASES OF THE BLASTS AT THE ATTENUATING REGION THEREOF.