US2294932A - Continuous manufacture of fibrous material - Google Patents

Description

Sept. 8, 1942. J. PAGE CONTINUOUS MANUFACTURE OF FIBROUS MATERIAL Filed Jan. l0,` 1939 Patented Sept. 8,1942

OFFICE CONTINUOUS MANUFACTURE or Famous.

MATERIAL John Page, Evanston,

States Gypsum Comp poration of Illinois Ill., assignor to` United any, Chicago, Ill., a cor- Appncauo January 10,1939, serial No. 250,156

(C1. :s3-s4) 7 Claims. The present invention relates to a continuous process of producing finely divided fibrous materia] in definitely controllable quantities so that it materials as a ller or aggregated.

The invention is particularly important in connection with the production of a brousller to be used in the continuous production of a gypsum-core wallboard.

The uniform continuous addition of small but Without becoming clumped 'definite amounts of fibrous material, for example a cementitious mixture such as is used for the core of a plaster board, is very diicult to accomplish, no matter how many precautions are taken to insure uniform feed of brous material. For example, in a plaster board core mixture sufcient to produce 1000 square feet of %inch board, it is desirable to add from 8 to 20 pounds of finely ground waste newspaper fibers to as much as 1200 pounds of calcined gypsum, together with other materials-employed to modify the latter. It will be self-evident that the uniform intermingling of these proportions of newspaper fibers and calcined gypsum presents unsual difficulties. Inasmuch as such wallboard is produced in a continuous manner in a continuously operating machine, it becomes necessary to effect the mixture of the fibers with the gypsum and the gauging water in a continuous manner, mixing, only small amounts at atime. Therefore the problem becomes even more diflicult than would be the case if a large quantity of fibers could be mixed with a large quantity ofgypsum. rMany attempts have been made to provide for uniform fiow of fibrous substance to such a gypsum mixture, but until the advent of the present invention such uniform feed has not been successfully accomplished. For example, the addition of the bers from a bin or hopper containing the fibrous aggregate or agglomerate described in the copending application of GeorgeD. King, Serial No. 250,165, iled January 10, 1939, may present certain dimculties. The material may pack down in a storage bin due to the weight of the superimposed material, so that the density of the substance at the greater than at the top and, if screw feed be employed, different weights of material will be fed, depending upon the amount of material in the bin. Inasmuch as the screw feeders are usually geared to the rate of pperation of the machine, it will be self-evident that uniform feed of the fibrous materialmay become diflimay be continuously fed into cementitious` bottom of the hopper will be cult; and only if the apparent density of the material being fed is kept uniform can uniform addition ina continuous operation be accomplished. For example, thel fibers described in. the said King application are of a very uffy nature, weighing approximately 2 pounds per cubic foot, but they are easily compressed; and in a hopper 4 feet high the density varies so greatly from the bottom to the top that the conventional feeding means hitherto employed become quite unreliable. If on the other hand a weight proportioning device is employed, careful control of the weight ofthe fibers also may present diiilculties. Thus, variations in temperature, humidity, and the like will materially affect the amount of fibers effectively fed. Although in the copending King application already referred to the method of making the fibrous product of the present invention and the product itself are broadly disclosed and claimed, by the present invention it becomes possible to produce the King product in such conditions that its uniform feed into a cementitious slurry becomes feasible and controllable. It will of course be apparent, in View of the details hereinafter given, that the objectives aimed at may be accomplished in a number of ways, all of them, however, being within the spirit and scope of the present invention. v

Therefore, the primary purpose of the present invention is to provide a means and method for Acontinuous production of a fibrous aggregate, of the type described in the said King application, in a continuous stream, which can be controlled as to its weight and characteristic properties so that, by proper co-ordination of the speed of operation of the' instrumentalities described herein with the speed of production of the wallboard machine for example, uniform incorporation of the brous aggregate withl the plaster -slurry can be effectively accomplished. One

way of obtaining uniform and continuous addition of fiber is described in the copending application of Welty, Page & Bygden, Serial No. 250,152, filed January 10, 1939. In the said Welty, Page & By'gden process a continuous sheet of waste trimmed from .a paper-making machine is continuously disintegrated and added in a fibrous condition to a cementitious mixture. In the present invention, however, continuous as well as discontinuous sheets may be' employed because of the apparatus set-up and the interconnection of the Various instrumentalities about4 -to be described.

a continuous mannerunder the enlarged section I2.

' through the hopper I4,

' hopper In the .one-sheet drawing filed concurrently herewith and forming a part of the present specu iilcation there is illustrated in diagrammatic form one of the preferred embodiments of this invention. Referring to the said drawing, it will be seen that the invention may consist of a chip-forming mill A, a chip separator B, a chip hopper C, a spiked drum and co-operating brush D, a fiberizing mill E, a pneumatic duct F, a fiber separator G, and a screw conveyor H. In operating this combined apparatus, waste paper is fed into the chip-forming mill A through a chute I. This mill A is of the swing-hammer type, being actuated by a suitable electric motor 2 through a coupling 3 on a shaft 4. This chipforming mill reduces the large sheets of newspaper to flake-like particles which are educed from the mill A through conduit 5 and thereby transported to chip-separator portion 6 of the separator B. 'A blast of air, created by a fan 1 which is actuated by a pulley 8 mounted upon the aforementioned shaft 4 and a belt 9, conveys the flake-like particles through the conduit 5. In the chip separator 6, which is built in the form of a cyclone separator, the air is separated from the small paper chips and passes out through an air vent I0, the chips falling downwardly through a chip hopper II. At this stage of the, operations the flake-like material possesses suiilcient resiliency to withstand/ packing; and the chip hopper is so constructed as to prevent any arching or bridging therein as it becomes lled. It should be noticed that the upper portion of the chip hopper is constricted while the lower part I2 is expanded and leads to a rotatable spiked drum I3. The enlargement I2 prevents the arching or bridging of the chips or flakes and also aids in preventing the packing thereof as a result of the weight of the fibrous material. The paper chips are drawn from the chip hopper II by means of the spiked drum I3 which forms the lower obturating portion of The spiked drum I3 may revolve in a counterclockwise direction as seen on the drawing and is indicated by the arrow thereon, thus carrying the flakes out of the chamber I2 and discharging them in the form of individual flakes into a hopper I4. The spikes are relieved of any flakes by means of a rotating brush I5 which intermeshes with the spikes on the spiked drum I3. A retaining wall I6 at the lower part of the chip separator portion D prevents any of the particles from falling in the other direction, the result being that there will be a continuous feed of paper flakes down so that there will be a veritable snowstorm of flakes being continually fed into a disintegrating or hammer mill I1.

The feeding of the paper flakes from the chip I2 to the hopper I4 may be further controlled by a small plate I1a extending from the side walls of the chip hopper I2 toward the spikes on the drum I3. The plate I1a serves to prevent extrusion of the I3 and brush I5 in excessive quantities.

By reason of the continuously and freely falling feed of paper, the output of this mill 'may be accurately controlled by regulating the speed of rotation of the spiked drum I3. The mill is of standard construction and contains at the bottom thereof a screen I8 which will retain the small unberized flakes or confetti in the mill and prevent them from screen. The sloping side wall I8a may be broken as shown to provide a vent I8b. The sufficiently passing through the ground fibers pass through the screen I8 and fall into a duct I9 from which, by means of a fan 20 (actuated by an electric motor -2-I) they are caused to pass into the duct F which conducts them into the fiber separator G, in which the cyclonic eiect whirls them into little aggregates which are continuously discharged through a conduit 23. The air is drawn into the i'lberizing mill I1 through the vent 18D. The air passes along the side walls of the hopper and prevents the paper iiakes from collecting thereon, so that they are continuously drawn into the flberizing mill I1.

The major portion of the air isseparated from the ground fiber aggregate in the separator G through a vent 24. Within the ber separator there is a deilecting plate or baille 25 to give the fibers a suitable downward impetus. This baille 25 not only slows down the centrifugal force l'and thus' releases the major part of the moving influence but also diverts a small portion of the stream and directs it along the walls of the separator. The fibers, being of a very fine uffy nature, have a marked tendency to adhere to the walls of the separator and to accumulate thereon. This film increases in thickness until the weight thereof breaks at the point between it and thefwalls and the 'entire mass slides down the chute or conduit 23. Thisof course is highly undesirable because it will produce surges in the otherwise uniform distribution of the fibers which enter the screw conveyor H through the conduitA 23. This screw conveyor H feeds the comminuted fiber to the plaster-board forming machine. In order to overcome this possible surging of the fibrous material, the aforesaid baille means 25 is wound spirally around the inside of the air separator G, thus deflecting a portion of the air stream, which thus scours the walls of the chamber and keeps it free from the particles which would otherwise cling thereto. Only a very small portion of the air stream needs to be thus deflected, but it will serve to keep the walls of the air separator clean; and this feature causes the continuous discharge from the separator of a constant uniformlydense stream of comminuted fiber which is collected by the screw conveyor 26 and continuously conveyed to the plaster-board machine. The excess air from the material is vented through an air Vent 21.

In accordance with the above described apparatus, the steps for carrying out the process as Waste newspaper;

(2) The feeding of this flake-like material by means of a spiked drum in a uniform manner and in uniform quantities to a second flberizing mill;

(3) The comminution of these particles in they said fiberizing mill at a uniform rate and to a uniform degree of commin'ut'ion;

(4) The collection of the fibers from the fiberizing mill in a continuous and uniform manner; and

(5) The uniform feeding of fiberized material of substantially constant apparent density to the point of discharge or point of admixture with the cementitious material into which it is introduced as a ller.

It will be apparent that the speed of the two mills can be so co-ordinated with the speed of the production of the wallboard or other plasticmaterial machine that a constant supply oi' comminuted ilber can be obtained, so thataccurate `control 'o f the amount ofiibers introduced into the plastic mass can be assured. So far -as the applicant is aware, nohone has hitherto attempted to produce simultaneously with the production of a plastic slurry a constant supply of uninecessary for the purpose of the present invention to describe them in any mechanical detail; and the detailed construction of the spiked drum and brush is so obviously indicated on the drawing that detailed sectional drawings vthereof are unnecessary, as any well trainedv mechanic will be able to construct a devicelike that shown in the drawing by merely following it and employing his mechanical knowledge. Suitable trunnions, shafting and means for applying motive power to the spiked drum I3 andthe brush Hi are of course provided, although they are not shown in the'drawing, as they are not new in themselves and are not new in the industry.

While the spiked drum and the brush are shown as particularly efiicacious means for lfeeding chips or akes to the disintegrating or fiberizing mill, equivalent constant-feed devices may be substituted therefor without departing from the fundamental principles of the present invention,

and such substitution is to be construed as strictly within contemplation of the inventor and to be encompassed within the scope of his claims.

Saving for himself such equivalents as will readily occur to those skilled in the art to which this application pertains; the inventor claims:

l. The process of continuously and uniformly producing a stream of loosely interlaced bulky fibrous material which comprises the steps of feeding fibrous sheets to a comminuting means of the hammer-mill type in which said sheets are initially reduced to aked form, pneumatically moving the thus produced flakes to a cyclone air separator and from the latter discharging the i flakes to a hopper adapted to prevent thefpacking of the flakes therein, uniformly and continuously removing a predetermined bulk of said flakes from said hopper and feeding it continuously and ,uniformly into la second comminuting means. of the hammer-mill type in which said akes are comminuted essentially to their initially fibrous condition, pneumatically transferring the thus formed fibers to a second cyclone aggregates, and removing ksaid aggregates by means of a blast-deiiecti'ng device from said swirling zene at a continuous and uniform rate.

2. Apparatus for the continuous production of a uniform supply of comminuted brous material which comprises the combination of a chipforming mill having swing-hammer comminutsaid flberizing mill being provided with sifting means for retaining insuiliciently comminuted chips and for passing sumciently comminuted fibers; pneumatic conveying means leading from said flberizing mill; a separator into which said pneumatic conveying means feeds, said separator being provided with an internal baille to obtain deflection of the air currents entering the same, so as to produce swirling movement of the fibrous particles therein, whereby they become aggregated to form loosely intertwined aggregates of fibers; discharge means on said separator comprising a downwardly directed chute, and a screw conveyor intowhich said chute leads'for conveying to any determined point the product issuing from said chute.

3. Apparatus for the continuous production of a uniform supply of comminuted fibrous material which comprises a chip-forming mill of the swing-hammer type, a pneumatic conveyor there- .with connected leading to va chip separator, a chip separator of the cyclone type and provided with a narrowed portion leading to a chip hopper; a chip hopper the bottom of which is closed by means of a chip-feeding mechanism which itself comprises the combination of a rotatable V cylindrical drum provided with peripheral spikes extending therefrom anda therewith co-operat ing rotary brush and means for rotating said spiked drum and brush; a flberizing mill and means for feeding the'chips delivered by said spiked drum to said fiberizing mill, the latter being of the swing-hammer type and provided with sifting means to separate insufficiently ground from sufficiently ground material; pneumatic means connected with said berlzing mill for conveying the therein produced fibers to a fiber separator, a ber separator having a conical bottom and provided at a point near the intake thereof with a spiral baille to cause the incoming liber-laden air stream to assume a spiral course, whereby the fibers are separated and caused to,agglomerate into small fibrous aggregates; means on said separator, comprising a chute, for continuously discharging the fibrous aggregates produced in the separator; and a conveying means connected with said chute for transporting the aggregates to their point of use.

4. An apparatus `for continuously mixing a stream of disintegrated paper fibers with a stream of cementitious material which comprises a conveyor means for providing a uniform and continuous iiow of cementitious material, a mill of the swing hammer type for comminuting a paper web into ake form, a comminuting means for berizlng the flakes thus produced, a

temporary flake storage chamber positioned between said mill and said comminuting means, a pneumatic conveyor means including an air separator for conveying said flakes from4 said mill to said temporary storage chamber, a positive feeding mechanism associated with the discharge end of said chamber for introducing said flakes into said comminuting means at a substantially uniform, constant, predetermined rate, means for introducing said paper web into said mill, and pneumatic means including a second air separator for discharging the resulting stream of disintegrated paper lfibers from the comminuting means at said predetermined rate into said conveyor means whereby a continuously advancing mixture containing constant proportions of fibers andI cementitious material is produced.

5. An apparatus for continuing mixing a nberswith an able spiked drum.mechanism .adapted to reitious material move chips from said hopper to said flberizing means for mill at a substantially uniform rate, and pneud continuous flow of matic means for discharging comminuted nbrous mmer mill for materials from said fiberizing mill at said unio flake form rate, also said pneumatic means including ing means for fiberizing the a separator of the cyclone type. l

d, a temporary flake storage 7. The continuous process of uniformly incorbetween said mill and said porating a loose fibrous material with a s, a pneumatic conveyor l0 cementitious material which comprises partially separator for condisintegrating by impact a web of paper to a ill to said tempoconfetti-like mass. passing said mass through e feeding mechaan air separating zone, collecting said mass in d drum and a temporary storage zone, separately and coniated with the discharge tinuously removing said mass from said storage oducing said akes zone and-causing -it to flowat a substantially ans at a substantially constant rate, further disintegrating said mass d rate, means tothefbrous state at the rate' at vwhich it is mill in i removed from said storage zone, discharging the t, and pneumatic means inresulting fibrous mass into a'second air separatdisintegrated paper stream of cement which comprises a screw conveyor providing a un cementitious ma comminuting an a l form. a comminut flakes thus produce hopper positioned comminuting mean means including a cyclone veying'said flakes rary storage cham nism including a ro cleaning brush assoc end of said chamb into said comminuting me constant, predetermine id paper web into said terial, a swing ha dvancing paper web int from said m ber, a positiv tatable spike for introducing sa a continuous shee cluding a second cyclone separator for discharging zone, separately providing a continuously disintegrated paper moving4 stream of.v said cementitious material, ing means at said precontinuously discharging aconstant stream of ing the resulting fibers from the comminut determined rate into said screw conveyor means, the 'fibrous mass from said second air separating sly advancing mixture conzonevinto said stream of 4cementitious material,

tions of fibers and and controlling the rate at which .the confettiwhereby a continuou taining constant cementitious material is produced.

like mass passes from said temporary storage the continuous produczone to the zone of final disintegration in accordly of comminuted fibrous ance with the rate of movement of said stream chip forming mill of cementitious material whereby the proportion including of fibrous material to the cementitious material r connected therein the final 'mix is maintained substantially hopper, a chip hopper, a constant. l

tely operated rotat- JOHN PAGE.

6. An apparatus for tion of a uniform supp material which comprises a of the swing hammer type, a pneumatic chip sep with leading to a chip chip flberizing mill, a separa

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