US1542915A - Paper yarn and process of producing the same - Google Patents

Description

June 23, 1925- 1,542,915

J. C. SHERMAN PAPER YARN AND PROCESS OF PRODUCING THE SAME Filed Nov. 16', 1921 4 Sheets-Sheet 1 fivenlifir (707272 615736;7093

June 23, 1925.

J. C. SHERMAN PAPER YARN AND PROCESS OF PRODUCING THE SAME 4 Sheets-Sheet 2 Filed Nov. 16, 1921 June 23, 1925. 1,542,915

' J. c. SHERMAN PAPER YARN AND PROCESS OF PRODUCING THE SAME Filed Nov. 16, 1921 4 Shets-Sheet s 4 7aw7,% v (70% 63 5726777aan June 23, 1925.

, 1,542,915 J. c. SHERMAN PAPER YARN AND PROCESS OF PRODUCING THE SAME Filed NOV. 16, 1921 4 Sheets-Sheet 4 21ml I. A}

Patented June 23, 1925.

UNITED STATES 1,542,915 PATENT OFFICE.

JOHN c. SHERMAN, or PORTLAND, AINE, ASSIGN-OR TO BROWN COMPANY, or

BERLIN, NEW HAMPSHIRE,

A. CORPORATION OF MAINE.

Application filed November To all whom it may concern:

Be it known that I, JOHN C. SHERMAN, a citizen of the United States, residing at Portland, in the county of Cumberland and State of Maine, have invented new and useful Improvements in Paper Yarns and Processes of Producing the Same, of which the following'is a specification.

This invention has relation to the formation from wood pulp of rovings, yarn, thread or cords.

In carrying'out my invention I utilize wood pulp in the form of a'web of proper width and thickness, and for this purpose I may employ the pulp strips as they are delivered from a web-forming machine, or may employ strips cut from a previously formed and dried Web. In either case, the strips are wet, in the one case with water remaining therein during the web formation, and in the other case with water with which the strips are wetted. While it is obvious that strips formed of various kinds of pulp may be utilized for this purpose, it is preferable that a chemical wood pulp should be used because of the length of the cellulose fibers resulting from the mode of production thereof. In fact, in many cases,

I prefer to employ wood pulp produced by the sulphate process so-called, in combination with other well known ingredients of a paper furnish.

Many recognized methods exist for the forming of rovings from textile fibers, such as cotton, linen, etc., in the production of yarns or rovings, in all of which methods 1t-,is essential that the fibers utilized shall possess a length substantially greater than the length of the chemical wood fibers which are usually of the order of 3 millimeters in length or less, but no method has thus far appeared for utilizing cellulose fibers of such short length by known textile processes; and one object of the present invention is to provide means whereby these cellulose or wood fibers in combination with other well known ingredients of a paper furnish may now be utilized to produce yarns, rovings, etc., possessing a strength comparable to' existing textile products made from longer fiber.

It is impossible to accomplish this result with dry cellulose fibers, but I have found that, when such fibers possess the requisite amount of water I am able by my process herein to 1 be described to produce strong 16, 1921. Serial No. 515,484.

rovings, yarn, etc. To accomplishthis'result, it is essential that the sulphite or'other cellulose fiber strip shallbe substantially saturated, as with water, but free from all surplus fluid. It is also desirable that the fibers should be more or less hydrated in the beating operation in order to furnish the requisite amount of cementitious or gelatinous cellulose hydrate for binding the fibers together in the formation of the web and the roving. Consequently it is desirable or necessary that the stock should be beaten primarily to a slow state or one in which )it is of a more or less slimy character due to the presence of mucilaginous hydrate. This is true whether the rovings be formed of the wet pulp as delivered from the web-forming mechanism or whether the web be initially driedafter its formation and then wetted so as to have the desirable water content'at the time'of its formation into the yarn or thread. For the purpose of further describing but not limiting my invention, I may say that sulphate or sulphite pulp, suitably beaten and otherwise prepared for the production of a tough tissue paper, has the condition which I prefer my pulp to have for my process.

According to my process, the wet strips two endless belts arranged with theirinner stretches confronting one another but with the belts arranged at an angle one to the other, with mechanism by which the belts are caused to travel with their inner stretches moving in the same general direc tion but in crossing paths. 'The' wet strip is fed to said belts so as to be moved longitudinally of its length thereby, and, while so moving, is convoluted transversely, the re sult being that the strip moves in a straight line during the action of the belts thereon and is delivered in the form of a round rod or roving which is compacted and of little or no variation inthickness. Inasmuch as the belts travel unidirectionally and have no independent lateral movement, they may be moved at relatively high speed so as to afford rapid production of the rods or rovings. The rovings thus produced may be formed into coils in the usual cans employed for a like purpose in the production of textile yarns; or, being still in a moist state,

. they may be subjected to a twisting operation, or a plurality of strands may be twisted to form a thread or cord. The relative angularity of the confronting stretches of the belt is important. Their angularity should be such that the same pair of belts may be utilized for simultaneously treating a plurality of independent closely-spaced strips, for, with the increase in the degree of angularity in the belts, there is increasing danger of the stripsbeing rolled together so as to lose their individuality. relative angularity exceed a certain limit, there is the danger that the strips which are being rolled and convoluted will be sub jected to too great transverse strain with the result that the roving is broken. For securing the best results in the primary functioning of the belts which is here dis. cussed, the angularity of the belts should not 'be excessive, as hereinafter explained more at length.

. On the accompanying drawings, I have indicated conventionally simple forms of apparatus which may be utilized in carrying out my process, but to the employment of which it will be understood the'invention is not necessarily limited.

Referring to these drawings,

Figure 1 represents, more or less diagrammatically, an apparatus for producing -a plurality of pulp strips and for forming them into rovings.

Figure 2 re resents a plan view of the strips of pulp eing delivered from thecylinder mold.

4 Figure 3 represents in front elevation the instrumentality by which the several pulp strips are convoluted and compacted into rovings, only one such strip being shown.

Figure 4 represents in end elevation one of the belts and the supporting mechanism therefor.

Figure 5 represents a section on the line 55 of Figure 3.

Figure 6 shows more or less conventionally an apparatus which may be employed for the formation of rovings from paper strips.

Figure 7 is a plan View of some of the instrumentalities shown in Figure 6.

Figures 8 and 9 illustrate more or less conventionally the changes of superficial forms encountered by a strip during its formation into a roving.

Referring first to Figures 1 and 2, I have indicated at 10 in conventional form the vat of a web-forming machine, into which the aqueous pulp stock is delivered for forma- If the tion into the web upon a cylinder mold 11. This cylinder mold may be formed in, any suitable or convenient way for the purpose of forming a plurality of strips. As indicated, the foraminous shell of the cylinder is provided with parallel imperforate metallic circumferential strips 12 so that the web delivered by the cylinder will be in the form of separate relatively narrow strips. At 13 I have indicated conventionally a blanket or felt which removes the strips from the cyllieu of that shown and thus described. In

fact, as I have previously indicated, I may employ strips of previously formed and wholly or partially dried paper in which case the strips ,are caused to be wetted to the desired degree by carrying them over a moistening roller, or by passing them through a bath of fluid or by subjecting them to the action of spray, steam or the like, the surplus fluid being removed, if 'nec-. essary, bysqueeze or pressure rolls. In an event, however, as I have previously state the strips should be wet when being delivered to the inst-rumentality for forming them into rovings, so that a further hydration of the cellulose fibers may take place during the operation of the'rod or rovingforming instrumentalities.

Referring now to Figures 3 to 5 inclusive,20, 21 indicate two belts having their inner stretches 22, 23 in confronting relation. These belts should be formed of or faced with such material, e. g., vulcanized rubber, that they will frictionally engage the strips. Ordinarily I employ belts having a canvas or other textile body with a rubber face vulcanized thereon. Of course, if desired, the inner faces of the belts may be similarl provided with a coating of rubber that t ey may frictionally engage the rolls over which they run. For supporting and driving these belts,- I employ the two pairs of rolls indicated at 25, 26 and 27, 28,

port of the rolls, except that of course provision must be made for so mounting the rolls that the inner faces of thebelts carried thereby may be arranged at proper angu'lar ity one to the other, so as to move in crossing paths. As shown more or less conventionally in Figures 3 and t, these rolls are formed on or secured to shafts 29, 30, 31, 32 which are journaled in suitable bearings in frames afforded for the purpose.

It 1s desirable that the rolls and their shafts should be capable of adjustment, and to this end the boxes, in which theshafts are journaled, are preferably adjustable relatively to the frame. Again, it is also desirable, for the purpose of varying the relative angularity of the belts,-that the frames themselves should be capable of angular adjustment one relatively to the other. Thismay likewise be accomplishedby devices of any suitable character. There are two frames, each shown more or less conventionally as comprising a pair of upright side standards mounted upon a suitable base. The bases for. the frames are indicated at 33 and 34 respectively. The base 33 is provided with the upright standards 35,36, while from the base 34 rise the standards or uprights 37, 38. These frames may be referred to conveniently as the front and rear frames, that comprising the base 33 and the standards or uprights 35, 36 being the front frame. These two frames are shown as being supported by a table 40 to which they. are secured by bolts and nuts 41 and 42 with suitable washers 43 which are properly beveled. The bolts pass upwardly through elongated slots formed in the base portions of the frame. As indicating a convenient means for providing for the relative angularity of the belts 20, 21, I have shown wedge-shaped shims 44, 45 which are interposed between the frames and the table on which they rest. Thesewedges may be of such angularity that'the relative angularity' of the belts is' substantially 10 or less. Each shim, if used, is, of course, properly slotted to permit the bolts 41 to pass therethrough and also to permit the longitudinal adjustment of the-shims 'to raise, or lower the frames supportedthereby. As I have indicated the frames as being made of wood, I havealso shown angle irons 46 for increasing their rigidity. The base portion of each angle iron may be secured to the base of the associated. frame by countersunk bolts 47 and nuts 48, as shown in Figure 4. These devices, however, are merely conventional or incidental features of construction and relatively unimportant. The shafts 29 to 32 inclusive are journaled in suitable boxes, those for the shaft 29 being indicated at 49 and those for the shaft 26 being indicated at 50. There are similar boxes for the shafts 31, 32, supported by the front frame. Each box is capable of ad-' justment longitudinally of its supporting upright, and to this end may be secured in place by bolts 51, 51 passed through a slot in the frame and secured after adjustment by nuts 52. In this way, each of the rolls 29 to 32 inclusive may be adjusted relatively to the associated roll of the pair to. keep the source of power. Of course, the rolls 26, 28 i must be driven in opposite directions so that the confronting stretches 22, 23 of the belts may move in the same general direction and at substantially the same rate of linear speed. I find it desirable to afford means for ensuring that the confronting stretches of the belts will properly engage the pulp strips which are fedthereto, and, of course, any suitable devices may be employed for pressing these stretches of the belts towards one another. For this purpose, I may employ two pressure members 57 58 for engaging the inner faces of the stretches 22, 23 of the belts. To reduce the friction between the belts and such pressure members, the said members may be faced with sheet metal, i. e., polished brass or other relatively noncorrodible material, as indicated at 59, 60. These members 57, 58 may be pressed towards each other by any suitable yielding devices. For example, as indicated in Figure 4, each pressure member at each end may be pivotally attached to two rods 61, 62 arranged to slide relatively loosely in guides 63, afforded by lugs projecting laterally from plates 64 secured to the uprights of the frame with which said pressure member and its corresponding belt are associated. A helical spring 65 is soarranged on each rod that one end rests against the rear guide 63 and the other against a cross pin 66 passed through ,the rod. As a result of this construction, each pressure member is supported in place and is pressed yieldingly towards the opposite member. In-

stead of directly engaging the rear guides 63, the rear ends ofthe helical spring 65 may engage the ends of threaded sleeves, 67 which are threaded into the guides 63. By rotating these sleeves, the tension of the springs may be increased or diminished as desired. Inasmuch as there is an adjusting sleeve 67 for each spring, it is apparent that, as the stretches 22, 23 of the belts pass downwardly between the pressure members, they may be subjected to increasing pressure by so adjusting the threaded sleeves that the lower ends of the pressure members are pressed together with greater force than the upper ends.

To prevent downward or longitudinal disrelatively one to the other.

"placement of the pressure members 57 and support the shafts 29 and 31, and at the other ends to the rods 62.

As a result of the construction thus described, it will be seen that the belts, which operate on the pulp strips, are caused to travel in the same general direction downwardly as indicated by the arrows in Figure 5, and that, during their downward movement, they travel in crossing paths. Consequently, when a pulp or paper strip having the proper moisture content is so delivered as to be gripped by the belts, it is carried downwardly with them and at. the same time is convoluted laterally, twisted and compacted into a roving which is practically round in cross section, with one edge of the strip forming the center of the roving. Since the cellulose fibers have been more or less hydrated and are in a wet state in addition, they are, by the pressure of the belts, cemented together and more or less interfelted. While the belts, because of their rubber facing, more or less positively grip the strip and the roving into which it is formed, nevertheless the belts are pressed yieldingly towards each other so as not to tear the fibers apart or destroy their initially interfelted relation. It is obvious, however, that in a yarn or roving it is desirable that the fibers shall lie along a longitudinal direction or axis of the roving. This result can be best accomplished with my invention if the fibers are delivered to the belts from a pulp-forming machine adapted to deliver the fibers along the axial direction of the strip of pulp. Thus I may use a suitably designed cylinder mold for initial 1y forming the web. Furthermore, to" secure substantially this longitudinal lie of the fibers within the roving, it is important that the strip of wet pulp or wetted paper, in passing between the belts, shall be moved axially forward over amuch greater distance than the lateral displacement produced by the angularity of the two belts As above stated, an angularity of 10 accomplishes this desirable resultin the particular instrumentality as here described and illustrated. If the angularity be excessive, the wet strip is so tightly twisted upon itself in such way that the fibers no longer lie axially, with the result. that the roving will not be strong but will tend to break before emerging from the belts. It is evident that the number of twists, which may be imparted to the ro'ving between the point where the strip enters betweeh and the roving emerges from the belts, will depend upon two factors, to wit: 'the relatively angularity of the belts and the length of the contacting inner stretches of the belts. is obvious that two belts, po-

' ing members.

sitioned as herein described with a certain angularity, will tend to be displaced laterally upon their individual rollers. Therefore one belt will tend to pile up upon the supporting frame-work at one side of the device, and the other belt. to pile up similarly upon the opposite frame of its support- To overcome this tendency, it is necessary only to introduce between the belts a plurality of strips of wetted paper or wet pulp, whereupon these wet strips counteract the tendency of the belts to undergo lateral displacement, with the result that the belts may float in mid position substantially as if carried upon crowned pulleys. If, however, the belts are not doing work upon the rovings throughout. their entire working faces, or if the adjustment of the working parts be faulty, the piling up referred to will occur and must be counteracted by increasing the distance between the rollers which support a given belt at that side of the belt which tends to pile up.

Preferably, as each strip passes between the belts and is formed into a roving, it is subjected to increasing pressure, this being efi'ected by adjustment of the springs which bear against the pressure members; that is, by decreasing the pressure of the; upper springs and increasing the pressure of the lower springs upon the pressure members. Such adjustment may not, in any given instance, be imperative, however, because if the contacting stretches of the belts be substantially parallel it is obvious that the strip as it becomes a roving during its transit between the belts will acquire a continually increasing diameter until it is comcause the rovings to stick to one or the other of the two belts. To counteract this tendency, the roving is permitted to fall by its own weight through a substantial distance before it is coiled up in a can or is wound .upon a bobbin or a spool. This overcomes any tendency of the rovings to wind up with the belts. Obviously I may further counteract the possible tendency of the rovings to stick to the belts by providing doctors or scrapers so located as to deflect any rovings, which may stick to the belts upon their upwardly moving portions, and cause these to drop down again into'their proper position, but since such doctors and equivalent de- ,vices are well established in the pulp and paper making art they have not been shown. it will be noted that thestrip is led to the belts adjacent to their engagement with theirt " upper rolls 25 and 27 which are substantiallyopposite to each other, where, as shown clearly in Figure 5, the belts form opposite downwardly moving sides of a hopper-like structure acting to conduct the end of a strip contacting therewith into proper posi- .tion' between the confronting stretches of the belts. \The threading of a strip between the belts is thus a simple matter,- it being only necessary to direct the end of the strip toward this hopper structure into contact with either of the belts. In Figure 1, I have indicated astrip at-a and the roving formed thereby at b; The roving b is shown as passing downwardly into a stationary roving can indicated at 70,

it being unnecessary to rotate the can as the roving emerges from the belts with an inherent tendency to coil if it is dropped free. In Figure 1, the roving can 70 is indicated conventionally as being at the right end of the apparatus for the purpose of clearness. In place of the roving can, as shown in Figure 1, the roving may pass to a suitable spooling mechanism as indicated at 75 in Figure 61' It is quite-evident that, instead of preserving the identity of the individual 'flrovings as by coiling them in. individual 0 cans or winding them on individual spools, the entire number ofvstrips emerging from the belts may be divided into groups, the rovings of one group may be brought together and the several groups delivered to a second instrumentality comprising crossed belts (similar to those at 20 and 21), whereby each group of rovings is formed into a thread having an equal number of strands. While for many purposes it is desirable to 40 treat the initially wet pulp delivered from the forming cylinderfyet, for other purposes, it is des1rable to treat strips of previously formed'and dried paper. In, Figures 6 and 7, I haveshown conventionally an apparatus in which suchlatterstrips oi paper may be conditioned for treatment. In using paper strips, I. refer to have them delivered in the form 0 separate rolls 100 in which the cores are hollow so that they may be slipped upon a supporting shaft or bar 101 and soy that each roll may revolve independently of the adjacent rolls. The

free ends of the strips drawn from the rolls are passed between feed rolls indicated at Y 102, 103, one at least of which is driven so that the strips may all be fed at thesame linear feed. It is necessary that the strips should be su plied with the proper'degree ofmoistureor their subsequent'for'mation 80 into rods or rovings. This mi ht well be accomplished by passing the strips through an aqueous bath, or they may be passed over a roll which dips into the bath as shown upon the drawings. The moistening liquid is illustrated as being contained in a vat'or rovings. Any suitable appliances may be tively.

ank 104, into which dips a moistening roll "105 over which the strips pass to a guide roll 107 prior to their delivery to the crossed belts by which they are formed into rods or utilized for causing one of the pressure rolls, the moistening roll and the guide roll 107 to be driven at the same peripheral speed and atthe surface speed of. the forming belts, particularly where fine strips of unusual delicacy are employed in making fine roving. VVhere strips of stronger quality are utilized, I prefer to let the strips themselves rotate the moistening roller by-their own frictional contact, for the purpose of subjecting them to a slight drawing or straining effect, which, in some cases, assists in conserving or increasing the desirable formation or arrangement of fibers lengthf wise of'the strips. I have illustrated conventionally an endless belt 108 which is engaged with the end of the roll 103 for rotating the same and which is'driven by one of the forming belts, being passed between the belts near their outer edges so as to move at a linear speed equal to that of the belts. This endless belt 108 is illustrated as being passed around a take-up roll 1 9. Of course, it, could, if desired, be engaged with rolls 105 and 107 so as to drive themposi- Care should be taken, in any event, to prevent an excess of moisture in the strips, whether they be wetted as when utilizing already formed and dried'strips, or in utilizing strips as delivered from the cylinder mold. On the other hand, it is desir able that there should not be a deficiency of moisture, as in such case the strips cannot be properly formed into rods or rovings. Where previously formed and dried stripsare employed, I prefer in ordinary cases to use water as the moistening agent, but it .is evident, ofcourse, that I may substitute a sizing compound including a hydrating 'agent'.

As a result of experience and much experimental Work, I have come to the conclusion that, when the pulp or paper strips, having a suflicient free-water content, are subjected to the action of the rod-forming belts, the cellulose fibers are hydrated to a considerable extent, and that the mucilaginous hydrate serves as a cementing or' binding agent to bind the fibers together in the completed rod or roving. This is due, I believe, to .the noticeable operations which occur during the treatment of the strips with the belts by which they are convoluted transversely. V

First, the wet or wetted strip enters between the belts where it is first pressed between them with a slightly obliquely applied pressure, this obliquity of direction being due to the relative angularity of the 3 belts. This obliquity of pressure lines tends slightly to abrade one face of the now flat and compressed strip in, for example, a right-handed obliquity, by reason of the action of the belt in contact with that face, and slightly to abrade the opposite face of the same strip in, for example, a left-hand obliquity, by reason of the action of the other belt acting on said opposite face. These obliquely abrading functions persist for an appreciable interval during which the wet and compressed strip is, as it were, sub- 'ected to two opposing forces, one imparted y the pressing belts which tends to main tain the strip flat and the other imparted by the obliquely shearing tendency of the belts to convolute the strips. During the incidence of these two opposing forces, considerable abrasion of the surfaces of the strips occurs.

Second, the partially loosened and abraded masses of pulp within the structure of the strip now pass on under the dominating obliquely twisting-up influence of the belts. The strip is no longer flat, and it is ragged at its edges and rough upon its faces, and in this condition it is suited to be further convoluted transversely with a far more intimate bondingand blending of the fibers of adjacent convolutions than would be possible if the strip were smooth.- These operations of the belts upon the fibers in the presence of thecontained moisture eflect a hydration of the fibers so that the strip emerges from between the belts with a remarkably increased tensile strength. Its strength is sufiicient to permit the operator to carry its free end by hand to spindles or other receiving devices far distant from the belts. A tougher and more durable roving is formed by permitting it 1 to dry in an unconstrained condition, as

when it is coiled in a roving can, as by permlttlng the roving to drop from the belts into a suitable can. If, on the other hand, the roving be spun or spooled immediately after emerging from the belts, it

obviously dries out under a condition of strain; but, even so, although it is not as strong as a roving dried without constraint, nevertheless it is sufiiciently strong for a great variety of purposes. In some cases, I prefer to have the rovings partially dried afterthein emergence from the belts, if a soft yarn is required. If it is desired to twist a roving into a tightly-twisted singleply yarn, such tight twisting is more readlly accomplished while the roving still contains more or lessfree water. Rovings, such as'furnished by the process and apparatus herein described, whether formed of pulp strips or moistened paper, may be conditioned and finished according to well known textile processes, they may be boiled in hot dyes without injury, or treated in accord ancewith the usual conditioning, bleaching or finishing processes for the formation of textile yarns or rovings or woven or knitted fabrics.

In an apparatus for forming rovings such as herein described it is obvious that the relative obliquity of the belts depends in a measure upon their length and their width, these factors themselves also being governed to some extent by the number of the strips which are being treated. Of course the working area of the belts, i. e., those portions of the faces of the belts between which the strips and the resulting rods on rovings are being treated, is relatively small as compared with the length of the belts. The relative obliquity of the belts in the same general direction must not be so great that the confronting face of one may pass entirely beyond the lateral edges of the other within the limits of the working area, as this might cause all of the rovings to be massed together.

The particular device here illustrated is designed and built to accommodate a plurality of separate but parallel strips occupying a lateral distance of approximately 8 inches, and in this device a relative obliquity belts is correspondingly reduced. In the case of the larger machine, this is effected by reducing the relative angularity of the belts from ten degrees to one degree. Obviously, however, the frictional character of the contacting belt stretches must be adapted to sustain the requisite frictional engagement between the strip and the stretches at any angle chosen for the operation of the machine, and this adaptation'is secured by the right selection of surfacing material in the construction of the belts. In general, as the angularity of the belts is reduced their surfaces must ossess an increasing frictional action which to some extent is afiorded by the appropriate adjustment of the mechanism to determine the pressure between said belts and to some extent by the right selection of belt-making materials. Thus if the angle be a small acute angle, canvas belts web, and it must for commercial reasons be as great as possible.

If the lineal or longitudinal motion of the strips and rovings be relatively fast it isdesirable to impart to them the rounding" up effect in a gentle rather than abrupt manner." Therefore for a fast running machine I prefer to employ relatively wide belts and to set them at a relative angle correspondingly small, retaining the rovings between said belts for a correspondingly longer longitudinal distance.

While, during the transit of the wet strips of pulp between the belts, more or less water is expressed in amount sufficient to leave a wet track on the belts, yet there apparently is little diminution of the water content in the rods or rovings as compared 'with that of the strips, since-the Water thus expressed is taken up by the oncoming lengths of the strips as they are engaged by the belts. It is apparent, of course, that the rods or rovings contain free water when emerging from the belts, although undoubtedly a portion of the initial free water content is' consumed in the hydration of the fibers, and this think accounts in vpart for the absence of accumulated water dripping from the belts when the machine is in operation. The wet rods or rovingsmight be said to have the fibers autogenously cemented by the hydrated cellulose which results from the action of the belts on the strips.

Figures 8 and 9 of the drawings are intended to show, more or less conventionally of course, the formation of a wetted tissue paper strip into a rod or roving. The strip, as indicated in Figure 8, has its face a; abraded .or rubbed, and'the side edge 3 is rolled over to form the center of the resulting rod, the remainder of the strip being coiled transversely around it. At the same time the rod is also twisted relatively loosely,

as best shown in Figure 9. The resulting rod or roving appears to be a homogeneous bundle or intimately cemented series of fibers, incapable of being uncoiled, and possessing a strength not greatly inferior to that of a cotton rovingof the same size. The mucilaginous cellulose hydrate, or hydrated portions of the fibers, bind the fibers together in .such manner that the yarn or rodmay be boiled without affecting its integrityor strength.- What I claim is: I v 1, A roving formed ofcellulose fibers, consisting of a fibrous strip initially coiled transversely about one of its longitudinal edges, and having the fibers of its coils one of its edges and having the fibers of the coils interfelted and cemented by the cellulosic mucilage of the fibers,

3. Roving formed of cellulose fibers and consisting of a round compacted fibrous strip coiled transversely about a longitudinal portion thereof as the center, the fibers of the coils being felted and being cemented together by the hydrated portions of such fibers.

4. Roving formed of cellulose fibers and consisting of a fibrous strip coiled trans versely about one of its edges and having the fibers of the coil interfelted and cemented by the cellulosic mucilage of the fibers, the whole being loosely twisted.

5. A method of making a roving which comprises progressively subjecting a continuous flat wet strip of cellulose fibers to obliquely applied frictional pressure ex- .erted in opposite directions laterally of the strip and in the same direction longitudinally thereof, whereby the strip is coiled transversely into cylindrical form and fed forwardly. Y

6. A method of making a rovingwhich comprises passing a continuous fiat wet strip of cellulose fibers between a pair of crossing obliquely arranged continuous frictional members which traverse unidireclindrical form.

tionally in paths oblique to and having a 7. The method of producing a roving which comprises progressively pressing and abrading the opposite faces of a flat wet strip of fibrous material and simultaneously feeding the strip forwardly and coiling it laterally about one edge while subjecting it to pressure.

8. A method of producinga roving which comprises feeding a fiat wet strip of fibrous material, pressing and abrading the opposite faces of said strip, and coilingsaid strip laterally about one edge whilesubjecting it to pressure, thereby producing a compacted substantially cylindrical 'rod or roving.

' '9. A method of producing from cellulose fibers a roving, which comprises feeding a flat'wet strip of such fibrous material, and subjecting the opposite faces of said strip to obliquely moving friction members, thereby pressing, roughening the faces of, and

coiling said strip transversely and compacting said strip into substantially cylindrical form.

10. A method of making a roving comprising feeding a flat strip of wet paper pulp longitudinally of its length, and, by the obliquely applied pressure of friction members, hydrating the cellulose fibers with the water contained in the strip, transversely coiling said strip about one edge thereof, compacting the resulting rod or roving and cementing the fibers thereof by the cellulose hydrate.

11. Mechanism for producing a roving from cellulose fibers which comprises a pair of crossed obliquely disposed endless belts havingv confronting faces moving in the same general direction to feed a wet strip of such material therebetween, and having a component of motion laterally of the path of motion of said strip in opposite directions to coil said strip laterally, and means for driving said belts.

12. Mechanism for producing a roving from cellulose fibers which comprises a pair of crossed obliquely disposed endless belts having confronting faces moving in the same" of such material therebetween, and having a component of motion laterally of the path of motion of said stripin opposite directions to coil said strip laterally, means for driving said belts, pressure members for pressing the confronting stretches of the belts together, and means for varying the pressureof said member upon the said 0011- longitudinal direction, whereby a strip of cellulose fibers directed into said hopperlike structure will be fed betweensaid confronting stretches.

15. Mechanism for producing a roving from cellulose fibers which comprises a pair of' obliquely disposed endless belts, 36 pair of rolls for supporting each belt and arranged to produce confronting stretches in said belts, and means for-driving said belts in a manner to cause said confronting stretches to move in the'same general direction, the rolls at the initial ends of said confronting stretches, being substantially opposite each other to receive and direct a strip of the material therebetween.

In testimony whereof I have aflixed my signature.

JOHN C. SHERMAN.

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