US3227536A

US3227536A - Apparatus for manufacturing fibers of thermoplastic material

Info

Publication number: US3227536A
Application number: US167091A
Authority: US
Inventors: Miles S Firnhaber
Original assignee: Individual
Current assignee: Individual
Priority date: 1962-01-18
Filing date: 1962-01-18
Publication date: 1966-01-04
Anticipated expiration: 1983-01-04

Description

Jan. 4, 1966 M. s. FIRNHABER APPARATUS FOR MANUFACTURING FIBERS OF THERMOPLASTIC MATERIAL Filed Jan. 18, 1962 United States Patent Ofiice Patented Jan. 4, 1966 3,227 536 APPARATUS FOR MANUliACTURING FIBERS F 'IHERMGPLASTIC MATERIAL Miles S. Firnhaber, Rte. 3, Pewaukee, Wis. Filed Jan. 18, 1962, Ser. No. 167,991 11 Claims. (Cl. 65-14) This invention relates to an improved apparatus for manufacturing fibers of thermoplastic material, and more particularly to a novel fiberizing rotor which can b readily disassembled to permit repair or replacement of its parts, and which rotor is adapted to produce a new form of fiber particularly well suited for insulation purposes.

In the production of mineral wool and similar insulating materials, molten glass or other thermoplastic material in a molten state is usually deposited on a rapidly spinning rotor and centrifugal force causes the same to be thrown therefrom in the form of individual filaments. These filaments are intercepted and acted upon by high speed jets of steam or the like as they leave the periphery of the rotor and are attenuated thereby into the fine, straight fibers ordinarily used in insulating materials. Such straight fibers have been utilized in the manufacture of mineral wool and similar products for a long time and have always been considered the most satisfactory type of fiber for that purpose. Applicant has discovered, however, that fibers having a curved or Wavy configuration adhere together better, have superior matting properties, and result in an insulating material of greater effectiveness.

With the above in mind, one of the two principal objects of the present invention is to provide a novel rotor assemblage which produces wavy fibers, in contrast to the straight fibers formed by conventional fiberizing rotors.

In the production of thermoplastic fibers as hereinabove described it is important, of course, that the molten material be maintained at a high temperature while it is on the rotor, and it is therefore necessary that the rotor be adapted to stand up under temperatures which sometimes exceed 2500 F. For this reason most prior fiberizing rotors, or at least the head portions thereof, have been constructed of a ceramic or refractory insulating material. Such ceramic rotors are unsatisfactory, however, for the reason that they tend to dry out and crack in a relatively short time, and must be replaced frequently. More recently, efforts have been made to construct fiberizing rotors entirely of metal, which rotors are much more durable and long-lasting than those formed of ceramic materials, but it has been found that the intense heat tends to cause deterioration of the structural integrity of the metal.

To minimize the problem of overheating and deterioration of the metal, recent metal rotors have included various integral means designed to cool the metal during operation, and in addition, such rotors have been so constructed that the rotor head and other portions which are susceptible to wear or deterioration can be detached and replaced on the rotor proper, thus eliminating the necessity for discarding and replacing the entire rotor. Unfortunately, however, the integral cooling means on such metal rotors have not proven satisfactory. Moreover, even though such rotors have been designed so that portions thereof could be detached and replaced in the event of damage, the intense heat frequently fuses said rotor parts together and makes it impossible to separate and remove the same.

With these considerations in mind, the second principal object of the present invention is to provide a novel, allmetal fiberizing rotor having improved cooling means thereon, and which rotor is so designed that while the head portion thereof is detachable, and will not become fused or frozen to the rotor proper, said rotor head is secured to the rotor in such a manner that it cannot be inadvertently separated therefrom during operation.

A further object of the present invention is to provide a fiberizing apparatus wherein the temperature and viscosity of the molten material can be effectively controlled during the fiberizing operation, thereby insuring that the fibers produced are of consistent quality.

Further objects of the present invention are to provide a fiberizing apparatus as above described which is relatively simple in design and construction and which is efficient and reliable in operation.

A still further object of the present invention is to provide a novel fiberizing apparatus which is especially weil adapted for use in the manufacture of mineral wool and similar insulating products, as hereinabove described, but which fiberiz-ing apparatus can also be advantageously employed in the manufacture of many diverse fibrous materials, including rayon and other synthetics.

With the above and other objects in view, the invention consists of the improved fiberizing apparatus and all of its parts and combinations as set forth in the claims, and all equivalents thereof.

In the accompanying drawing, illustrating one complete embodiment of the preferred form of the invention, and wherein the same reference numerals designate the same part-s in all of the views:

FIG. 1 is vertical sectional view of the fiberizing apparatus comprising the present invention;

FIG. 2 is a horizontal sectional view through the rotor, taken along line 22 of FIG. 1; and

FIG. 3 is a fragmentary side elevational view of the annular cooling rim, taken along line 33 of FIG. 2.

Basic structure and operation In the operation of a fiberizing apparatus of the general type illustrated (as is described in detail in my copending applications Serial No. 801,533 filed March 24, 1959, now Patent No. 3,048,885, and No. 19,209, filed April 1, 1960, now Patent No. 3,048,886), a stream of molten glass or other thermoplastic material in a molten state is delivered from a melting furnace through a tube 16 (FIG. 1) and is deposited thereby onto a rapidly spinning rotor, which is designated generally by the numeral 12 in the drawing. Said rotor is formed of metal and includes a cylindrical base portion 1a: which is rotatably drivably mounted on a shaft 18 connected to a motor or other prime mover, and mounted on the top of said base is a rotor head 24 having a dished material-receiving surface 14.

Surrounding and projecting above the rotor head 24 is a metal rim member 26 having a multiplicity of apertures 28 therethrough, and mounted thereabove in surrounding relationship to the delivery tube It is a circular gas chamber 36. Said gas chamber is connected by a conduit 38 to a suitable source of combustible gas under pressure, and depending from said gas chamber are a plurality of radiant burners 37 which are positioned to direct flames 39 against the dished top surface of the rotor, to maintain the thermoplastic material thereon at a predetermined temperature and viscosity.

As the rotor spins, the molten material is thrown therefrom by centrifugal force and is caused to pass through the apertures 28 in the sourrounding rim member 26, said rim performing the twofold function of attenuating the filaments and also preventing any incompletely-formed fibers or slugs from leaving the rotor and finding their way into the finished product. With respect to said rim, it is an advantageous feature of the illustrated rotor for the reasons described, but it is by no means critical to the novel concepts and structure comprising the present invention, and which will be hereinafter described, and the invention is not to be limited or confined to a rotor structure including such a rim. After the filaments leave the periphery of the rotor they are intercepted by high-speed, downwardly-directed jets 42 emitted from an annular steam or gas ring 46, said ring being connected by conduits 41 to a boiler or other source, and having a plurality of spaced discharge orifices in its bottom surface. Said jets 42 are designed to abruptly and violently change the direction of the filaments, thus attenuating the same still more as they solidify, and to direct said filaments downwardly into a receptacle or container therebelow.

As mentioned, the illustrated fiberizing rotor is formed entirely of metal, in contrasts to the ceramic or combination metal and ceramic rotors formerly used. in this respect, it has been found that an alloy consisting of chromium, nickel, and cobalt is very satisfactory, but other metals or alloys might be preferred for certain fiberizing operations and the particular metal employed is not critical to the present invention.

New rotor structure As will be seen in -lG. 1, the cylindrical rotor base 16 characterizing the present invention is provided with an enlarged or flanged upper portion 17 and seated thereon is a fiat, concentric ring or disc 29 of still greater diameter. The central portion of said disc 20' is open and the periphery of said disc is provided with oblique blades or fins 22 (FIG. 3) which are designed to function as fan blades when the rotor is in operation, as will be hereinafter described.

The rotor head 24- in the present improved rotor assemblage is seated on the disc 29, being smaller than said disc in diameter, and the aforementioned upstanding rim 26 included on the illustrated rotor closely but separably surrounds said rotor head. As is apparent in FIG. 1, both said rotor head 24 and rim 26 are tapered upwardly and inwardly, and surrounding said members is a novel locking ring 30 which is designed to detachably secure said members together and to the base 16.

Said locking ring 30 is wedgingly fitted over the tapered rim 26, the opening in said locking ring being slightly smaller in diameter than the diameter of the rim at its lowermost point. The inner, annular surface of said locking ring is vertical, in contrast to the inclined adjacent surface of the rim 26, the purpose of which will be seen, and in assembling the unit said locking ring is pressurably urged downwardly to clampingly retain said rim and rotor head members together. The ring St the disc 26, and the flanged upper portion 17 of the rotor base are provided with circumferentially-spaoed, registering apertures, and to secure said ring to the rotor base bolts 32 are projected through said registering apertures and fastened by nuts 34. Not only does this provide a simple means for detachably joining the component parts of the rotor, but during the fiberizing operation the intense heat on the metal head and rim members causes said members to expand and to become even more tightly wedged against the locking ring 36, thus eliminating the possibility of said members inadvertently separating or coming off during operation. After the rotor has been halted for a short time said head and rim members cool off and return to their original size, of course, and may then be readily separated from the rotor merely by removing the bolts 32 and withdrawing the locking ring 30.

Due to the angled nature of the upstanding rim 26 (or the tapered nature of the rotor head itself in the event the rotor does not include such a rim), there is a relatively small area of surface contact between said rim and the inner surface of the locking ring 313, and the possibility of fusion between said members is practically non-existent. Similarly, because the inner portion of the disc 26 is open there is relatively little surface contact between said disc and the underside of the rotor head, and little chance of permanent fusion between said members. Moreover, the airspace 21 provided by said disc between the rotor head and base members forms an insulating layer therebetween which prevents said base from becoming overheated.

As a result of the novel locking ring device characterizing the present improved rotor it is possible to quickly and easily remove and replace those portions of the rotor which are most susceptible to wear or deterioration, and it is not necessary to discard and replace the entire rotor in the event of damage. Moreover, the unique design of applicants assemblage minrnizes the possibility of the rotor components becoming fused or stuck together during operation, as frequently happens with those prior all-metal rotors wherein the component parts are intended to be separable.

Means for producing curved fibers In addition to the detachable and separable nature of the rotor assemblage characterizing the present invention and hereinabove described, the present invention is also novel in that it is designed to produce fibers having a curly or wavy configuration, in contrast to the straight fibers heretofore used in mineral wool and similar insulating products. As mentioned, such wavy fibers have superior matting qualities and have been found to produce a more effective insulating material.

As is illustrated in FIG. 1, a supplemental gas ring or chamber 44 formed of a pair of complementary,

semicircular sections

45 and 46 is mounted above and in surrounding relationship to the regular gas chamber 36, being spaced radially outwardly a short distance therebeyond. Said supplemental gas ring 44 is provided with depending burners 49 which are positioned to discharge gas flames 59 against the molten material filaments as said filaments are thrown from the periphery of the rotor, and before said filaments are intercepted by the steam jets .2 as hereinabove described. As shown, said

ring sections

45 and 46 include supply conduits 47 and 48, respectively, and in accordance with the present invention each of said sections is supplied with combustible gases at a different temperature. As a result, the flames 5t) emitted from the burners of the section 46 are of a different temperature than the flames 50 emitted from the burners of the other ring section 45.

When the thermoplastic fibers are thrown from the rotor by centrifugal force they naturally continue to travel in a generally circular path or orbit around the rotor top, and it has been found that by providing fiberengaging flames or blasts 50 and 50' of different temperatures on the opposite sides of the rotor the resulting changes in temperature encountered by the orbiting filaments causes said filaments to assume the desired, curly or wavy configuration. Moreover, the degree of curvature or deflection of the fibers can be controlled by regulating the temperature difference between the burner sections, thus permitting the production with one rotor of varying fiber configurations.

Summary of operation In the use of the novel fiberizing apparatus comprising the present invention, a stream of molten glass or similar thermoplastic material in a molten state is delivered from a melting furnace through the vertical tube 10 and is deposited thereby onto the upper surface 14 of the rapidly spinning rotor 12. Said molten material is thrown centrifugally from the rotor in the form of individual filaments or fibers, and as said fibers leave the rotor periphery they are engaged alternately by the flames 5t and 5t) emitted from the supplemental

gas chamber sections

45 and 46, said flames being of predetermined different temperatures and causing said fibers to assume a unique curved form. Said fibers then continue their outward travel until they are intercepted by the steam jets 42 which solidify the same and direct them down- Wardly into a suitable receptacle.

During the operation of the present rotor the aforementioned fins or blades 22 carried on the outer peripheral edge of the disc member function as fan blades and cause a cooling circulation of air against the exterior of the metal rotor, thus helping to prevent overheating and deterioration of the structural integrity of the metal. In addition, it has been found that the air turbulence created by said fan blades around the rotor has an efiect upon and improves the character of the fibers. In the event the rotor head 24 or its surrounding rim 26 should become damaged or eroded, they can be easily removed and replaced merely by removing the bolts 32 and locking ring 30, and it is unnecessary to discard and replace the entire rotor.

As will be readily appreciated from the foregoing detailed description, the present invention provides an improved apparatus for manufacturing fibers for insulating materials or for any other fibrous products. It is to be understood, of course, that variations or modifications in the device illustrated and described herein will undoubtedly suggest themselves to those skilled in the art, and all such variations and modifications are contemplated as may come within the scope of the following claims.

What I claim is:

1. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a generally cylindrical, metal rotor head seated on the top surface of said rotor body, said rotor head being smaller in diameter than said body top and being tapered upwardly; a locking ring wedgingly surrounding said rotor head, said locking ring having an inner diameter slightly less than the diameter of the bottom of said rotor head; bolts projected through registering apertures in said ring and body flange members to releasably secure said locking ring and rotor head to said rotor body; heat-emitting means mounted above and surrounding said rotor head, said heat-emitting means being positioned to discharge heat against molten material filaments thrown from said rotor head; and means for regulating the heat discharged by said heat-emitting means whereby greater heat is discharged around one portion of the rotor head than around another portion of said rotor head.

2. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a disc seated on the top surface of said rotor body, said disc being of a larger diameter than said rotor body; a plurality of fan blades carried by and spaced around the periphery of said disc; a generally cylindrical, metal rotor head seated on said disc, said rotor head being smaller in diameter than said disc and being tapered upwardly; a locking ring wedgingly surrounding said rotor head, said locking ring having an inner diameter slightly less than the diameter of the bottom of said rotor head; bolts projected through registering apertures in said ring, disc, and body flange members to releasably secure said locking ring and rotor head to said rotor body; a gas chamber mounted above and surrounding said rotor head, said gas chamber being formed of a plurality of sections; a plurality of burners depending from said gas chamber sections and positioned to discharge heat against molten material filaments thrown from said rotor head; and means for regulating the heat discharged by the burners of each of said gas chamber sections whereby the burners of each section emit heat of a different temperature.

3. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a disc seated on the top surface of said rotor body, said disc having an open central portion and being of a larger diameter than said rotor body; a plurality of fan blades carried by and spaced around the periphery of said disc; a generally cylindrical, metal rotor head seated on said disc, said rotor head being smaller in diameter than said disc and being tapered upwardly; a locking ring Wedgingly surrounding said rotor head, said locking ring having a vertical inner edge surface and having an inner diameter slightly less than the diameter of the bottom of said rotor head; bolts projected through registering aper tures in said ring, disc, and body flange members to re leasably secure said locking ring and rotor head to said rotor body; a jet ring mounted above and surrounding said rotor head, said jet ring being substantially larger in diameter than said rotor head; a circular gas chamber mounted above said rotor head, said gas chamber being formed of a pair of semi-circular sections; a plurality of burners depending from said gas chamber sections and positioned to discharge heat against molten material filaments thrown from said rotor head; and means for regulating the heat discharged by the burners of each of said gas chamber sections whereby the burners around one half of the rotor head emit more heat than the burners around the other half of said rotor head.

4. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a disc seated on the top surface of said rotor body, said disc having an open central portion and being of a larger diameter than said rotor body; a plurality of angled fan blades carried by and spaced around the periphery of said disc; a generally cylindrical, metal rotor head seated on said disc, said rotor head being smaller in diameter than said disc and being tapered upwardly; a similarly tapered, apertured metal rim separably mounted on and projecting above said rotor head; a locking ring Wedgingly surrounding said rotor head and rim members, said locking ring having a vertical inner edge surface and having an inner diameter slightly less than the diameter of the bottom of said rim; bolts projected through registering apertures in said ring, disc, and body flange members to releasably secure said locking ring, rim, and rotor head members to said rotor body; burner means mounted above said rotor head and positioned to direct heat against the top surface thereof; a jet ring mounted above and surrounding said rotor head, said jet ring being substantially larger than said rotor head in diameter; a circular gas chamber mounted above said rotor head, said gas chamber being formed of a pair of semi-circular sections; a plurality of burners depending from said gas chamber sections and positioned to discharge heat against molten material filaments thrown from said rotor head; and means for regulating the heat discharged by the burners of each of said gas chamber sections whereby the burners around one half of the rotor head emit more heat than the burners around the other half of said rotor head.

5. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a plurality of fan blades carried by and spaced around the periphery of said rotor body; a generally cylindrical, metal rotor head seated on the top surface of said rotor body, said rotor head being smaller in diameter than said rotor body flange and being tapered upwardly; a locking ring wedgingly surrounding said rotor head, said locking ring having an inner diameter slightly less than the diameter of the bottom of said rotor head; and bolts projected through registering apertures in said ring and body flange members to releasably secure said locking ring and rotor head to said rotor body.

6. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, aid rotor body having an annular flange adjacent its top surface; a disc seated on the top surface of said rotor body, said disc having an open central portion and being of a larger diameter than said rotor body; a plurality of fan blades carried by and spaced around the periphery of said disc; a generally cylindrical, metal rotor head seated on said disc, said rotor head being smaller in diameter than said disc and being tapered upwardly; a locking ring Wedgingly surrounding said rotor head, said locking ring having a vertical inner edge surface and having an inner diameter slightly less than the diameter of the bottom of said rotor head; and bolts projected through registering apertures in said ring, disc, and body flange members to releasably secure said locking ring and rotor head to said rotor body.

7. A fiber-forming apparatus, comprising: a rotor body rotatably drivably connected to a prime mover, said rotor body having an annular flange adjacent its top surface; a disc seated on the top surface of said rotor body, said disc having an open central portion and being of a larger diameter than said rotor body; a plurality of angled fan blades carried by and spaced around the periphery of said disc; a generally cylindrical, metal rotor head seated on said disc, said rotor head being smaller in diameter than said disc and being tapered upwardly; a similarly tapered, apertured metal rim separably mounted on and projecting above said rotor head; a locking ring wedgingly surrounding said rotor head and rim members, said locking ring having a vertical inner edge surface and having an inner diameter sli htly less than the diameter of the bottom of said rim; and bolts projected through registering apertures in said ring, disc, and body flange members to releasably secure said locking ring, rim, and rotor head members to said rotor body.

8. A fiber-forming apparatus comprising a rotatably mounted rotor body having a top surface with an annular flange, a spacer ring seated on said fiange, a rotor head seated on said ring and having a bottom, there being a cooling air chamber between the top surface of the rotor body and the bottom of said head and within said ring, a retaining ring seated on said spacer ring and surrounding the lower portion of said rotor head, and means extending through said retaining ring, spacer ring and flange releasably securing the parts in assembled position.

9. A rotor for use in a fiberizing apparatus comprising a rotatably mounted rotor body having a periphery, a spacer ring which is generally concentric with said rotor body positioned thereon and having its periphery extending along and adjacent the periphery of said rotor body,

8 a rotor head seated on said spacer ring, there being a cooling air chamber between said head and rotor body, fan blades carried by the periphery of said ring and projecting beyond the rotor body, and means securing the spacer ring and rotor head in assembled relationship on said rotor body.

10. A rotor for use in a fiberizing apparatus comprising a rotatably mounted rotor body having a periphery, a spacer ring which is generally concentric with said rotor body positioned thereon and having its periphery extend ing along and adjacent the periphery of said rotor body, a rotor head seated on said spacer ring, there being a cooling air chamber between said head and rotor body, fan blades carried by the periphery of said ring and projecting beyond the rotor body, and means removably securing the spacer ring and rotor head in assembled relationship on said rotor body.

11. A fiber-forming apparatus comprising a rotatably mounted rotor body having a top surface with an annular flange, a spacer ring seated on said flame, a generally cylindrical rotor head seated on said ring and having a bottom and an upwardly tapered periphery, there being an air chamber between the top surface of said rotor body and the bottom of said head and within said ring, an apertured rim surrounding said rotor head and projecting thereabove, and means including a retaining ring seated on said spacer ring and surrounding the lower portion of said rim for releasably securing the parts together.

References Cited by the Examiner UNITED STATES PATENTS 2,603,833 7/1952 Stalego et al. 18-26 X 2,609,566 9/1952 Slayter et al. 18-26 X 2,814,828 12/1957 Svende -14 2,949,632 8/1960 Kleist et al. 65-14 2,994,918 8/1961 Landers. 3,013,299 12/1961 Owens 18-473 X 3,048,885 8/1962 Firnhaber 65-15 3,048,886 8/1962 Firnhaber et al. 65-15 3,058,322 10/1962 Erard 65-14 FOREIGN PATENTS 147,032 6/1952 Australia.

DONALL H. SYLVESTER, Primary Examiner.

MICHAEL V. BRINDISI, Examiner.

Claims

1. A FIBER-FORMING APPARATUS, COMPRISING: A ROTOR BODY ROTATABLY DRIVABLY CONNECTED TO A PRIME MOVER, SAID ROTOR BODY HAVING AN ANNULAR FLANGE ADJACENT ITS TOP SURFACE; A GENERALLY CYLINDRICAL, METAL ROTOR HEAD SEATED ON THE TOP SURFACE OF SAID ROTOR BODY, SAID ROTOR HEAD BEING SMALLER IN DIAMETER THAN SAID BODY TOP AND BEING TAPERED UPWARDLY; A LOCKING RING WEDGINGLY SURROUNDING SAID ROTOR HEAD, SAID LOCKING RING HAVING AN INNER DIAMETER SLIGHTLY LESS THAN THE DIAMETER OF THE BOTTOM OF SAID ROTOR HEAD; BOLTS PROJECTED THROUGH REGISTERING APERTURES IN SAID RING AND BODY FLANGE MEMBERS TO RELEASABLY SECURE SAID LOCKING RING AND ROTOR HEAD TO SAID ROTOR BODY; HEAD-EMITTING MEANS MOUNTED ABOVE AND SURROUNDING SAID ROTOR HEAD, SAID HEAT-EMITTING MEANS BEING POSITIONED TO DISCHARGE HEAT AGAINST MOLTEN MATERIAL FILAMENTS THROWN FROM SAID ROTOR HEAD; AND MEANS FOR REGULATING THE HEAT DISCHARGED BY SAID HEAT-EMITTING MEANS WHEREBY GREATER HEAD IS DISCHARGED AROUND ONE PORTION OF THE ROTOR HEAD THAN AROUND ANOTHER PORTION OF SAID ROTOR HEAD.

10. A ROTOR FOR USE IN A FIBERIZING APPARATUS COMPRISING A ROTATABLY MOUNTED ROTOR BODY HAVING A PERIPHERY, A SPACER RING WHICH IS GENERALLY CONCENTRIC WITH SAID ROTOR BODY POSITIONED THEREON AND HAVING ITS PERIPHERY EXTENDING ALONG AND ADJACENT THE PERIPHERY OF SAID ROTOR BODY, A ROTOR HEAD SEATED ON SAID SPACER RING, THERE BEING A COOLING AIR CHAMBER BETWEEN SAID HEAD AND ROTOR BODY, FAN BLADES CARRIED BY THE PERIPHERY OF SAID RING AND PROJECTING BEYOND THE ROTOR BODY, AND MEANS REMOVABLY SECURING THE SPACER RING AND ROTOR HEAD IN ASSEMBLED RELATIONSHIP ON SAID ROTOR BODY.