US1867599A - Manufacture of pulp rovings - Google Patents

Description

July 19, M o SCHUR ET L H,8fi7,599

I MANUFACTURE'OF PULP ROVINGS File d June 27, 1931 Patented July 19, 1932 UNITED STATESv PATENT OFFICE MILTON 0. SGHUR AND WILLIAM B. MEGLITZ, OF BERLIN, NEW HAMPSHIRE, AS-

SIGNORS TO BROWN COMPANY, OF BERLIN, NEW HAMPSHIRE, A CORPORATION OF MAINE Application filed June 27,

This invention relates to the manufacture of pulp rovings, its object being to provide a method of and apparatus for producing rovings directly from an aqueous suspension in a satisfactory and economical man- I usual textile yarns in making twines, fabrics, and analogous products.

In accordance with our invention, we progressively deposit from aqueous suspension ribbons of pulp on a rotary cylinder mould of the type used in making paper, webs. While the ribbons are wet and still on the cylinder mould, we progressively furl or roll them out into continuous round bodies or rovings, whereupon the rovings may be collect ed and put through the desired subsequent manufacturing operations. The cylinder mould can be operated in combination with a pulp vat which is designed to deliver an aqueous pulp suspension continuously on one side of the mould periphery. The other side of the mould periphery can be engaged by a belt orits equivalent, movin at an angle to the direction of movement of the peripheral surface of the mould, whereby the pulp ribbons carried on the mould periphery are engaged at their edges by the belt and are furled or rolled out into round form. While passing from the pulp-depositing station to the furling station, the ribbons may undergo dewatering to a quasi-dough-like consistency, at which they are amenable to furling and at the sametime possess suflicient strength to maintain their integrity. In order to ensure rovings of uniformly good quality, it is necessary that the furling belt and the mould periphery meet at substantially the same rates of speed. This result may be had with-. qut difliculty when the belt derives its motion through frictional contact with the cylinder mould. Otherwise, it is necessary to drive the belt positively and to synchronize its speed through suitable mechanism with the speed of the cylinder mould.

With the foregoing and other features and MAN UFAOTURE OF PULP ROVINGS 1931. Serial No. 547,246.

objects in view, our invention will now be described in conjunction with the accom-.

panying drawing, wherein Figure 1 represents a section through an apparatus, including a vat, cylinder mould, and roving means embodying our invention.

F igure' 2 is a front view of the apparatus facing the roving means.

' Figure 3 is an enlarged fragmentary section on the line 33 of Figure 1.

Figure 1 represents a vertical section through a modified form of roving means.

Figure 5 is a fragmentary front view of the roving means, with the belt partly broken away to shoW how it is mounted on a supporting guide roll..

Referring in detail first to Figure 1 of the drawing, 1 represents a vat for supplying an aqueous pulp suspension at suitable consistency to-a rotary cylinder mould 2, one side of whose periphery constantly contacts with the body or pool of pulp suspension maintained at a predetermined depth in the vat. The cylinder mould is constructed to permit the progressive deposition thereon in spaced relationship of continuous ribbons of pulp from the body of aqueous pulp suspension.-

The particular cylinder mould illustrated is built up of heavy, rugged-parts, including a cylindrical shell 3, whose hollow interior is divided into several compartments or cylinders, A, B, C and D. These chambers are de fined by stationary partitions 4 extending radially from a common core 5, which passes through the enclosure 6 for the shell and serves as a means for supporting the partitions and the closures. The shell proper makes tight sliding contact with the outer edges of the partitions 3 and with the closures 6, and may be journaled near its ends for rotation by suitable means (not shown) in accordance with well-known practice. The wall of the shell 3 may, as best shown in F igure 3, be of substantial thickness and have'a series of spaced, peripheral grooves 7, of a width corresponding to the width of the ribbons to be formed. These grooves communicate throughout their length with the interior of the shell by spaced apertures 8 extending inwardly from the bottom of the grooves through the rest of the shell wall. The wall is covered exteriorly with wire cloth of, say, 45 or finer mesh, so that the pulp fibers again deposit out ofaqueous suspension as spaced ribbons 10 on those zones of cloth immediately above the grooves, while the water of the suspension passes into the interior of the shell by way of the grooves and the apertures. As the shell is rotated, it acts to strain or pick up pulp fibers as continuous ribbons from the pool of pulp suspension next to the peripheral portion progressing over the chamber A. The rate of pick-upf may .be promoted by creating suctio'n in the chamber A through a water-leg or suction pump whose suction terminal is an opening 11 through one of the closures 6 into the chamber A. The chamber B under the upper side of the shell may be similarly connected with.the terminal end 12 of a wet vacuum pump, so that as the shell carrying the wet pulp ribbons passes thereover, excessivewater is removed from the ribbons to reduce them to the water content at which they can be furled satisfactorily. The small chamber '0 adjacent to the chamber B is under the pressure of air or other suitable gaseous medium supplied through the opening 13, and which merely detaches or slightly lifts the suitably dewatered rib bons from the wire cloth just beforethey enter into the nip formed between the outer side of the shell and the confronting stretch of a roving belt 14 supported and guided on a pair of inclined terminal rolls 15. The belt engages theshell over a substantial arc of contact, and by virtue of friction is propelled at substantially the same rate of speed as the shell periphery, but at an angle to the direction of movement of, the shell periphery. The detached ribbons are thus furled or rolled out into rovings 16, which, after issuing from the nip may be collected by any suitable mechanism, for instance, by the pneumatic system described and claimed in application'Ser. No. 504,029, filed December 22, 1930, by Milton. 0. Schur. We. have desc r ibed the detachment of the ribbons from the mould prior to their furling, for the reason that the pillp fibers tend to become entangled in and stick to the wire cloth,'with the attendant danger of being non-uniform-- ly furled or of not being furled at all. If desired, however, only those edges of the ribbons which are to serve as the starters for furling operation may be detached from the wire cloth, for, once furling is initiated by the belt, it tends to go uniformly to completion. Because there is a tendency for the mould to propel the belt vertically and thus to cause it to ride out of position on the rolls 15, this tendency is preferably neutralized as by a horizontal roll 17, which rotates in a direction o posite to that of the mould by frictional engagement over the requisite arc of contact with the inoperative stretch of the belting. Either of therolls 15 or the neu tralizing roll 17 may be adjustably mounted so as to permit tightening or loosenin of the rovin belt, as well as to allow contro of the are c contact between the belt and the cylinder mould. The cylinder mould can be cleansed of any residual fibers clinging thereing 18 and issuing under pressure as a shower through the wire cloth. That part of the mould interior between the chambers C and D over which the mould p'wses immediately after roving need serve no useful function,

but may be closed ofi from the adjacent chambers by an arcuate wall 5 0 with which the shell makes nice sliding contact. Rather'than dependlng upon a neutralizing roll to keep the roving belt in place the raving belt may be anchored to chains, cables, or straps running in fixed paths. Thus, as illustrated in Figures 4 and 5, the roving belt may be made up of a wire cloth 19, of suitable 'mesh, attached to a plurality of spaced supporting straps 20, .each of which' fits nicely into grooves or tracks 21 formed a suitable source through the chamber openin the terminal rolls 22. The side thrust of .5 the cylinder mould on the wire is thus taken up by the side walls of the tracks and no displacement of the roving belt is possible.

In order to secure rovings of consistently uniform diameter, strength, and other characteristics, it is necessary that the pulp rib bons be of uniformly interfelted texture. This result is fostered by the use of a very dilute or thin pulp suspension and by sup plying the suspension in excess of the cylinder mould on which the ribbons are deposited. The pulp vat shown in Figure 1 is'capable of handling an excess of pulp suspension which is delivered at a fiber content of, say, about 1/50% or less, by way of a supply pipe 23 though the bottom 24 of the vet at a point somewhat removed from the cylinder mould. The pulp sutslpension flows under a horizontal plate or be e 25 and flows past the clearance or throat 26 between the baflle and cylinder mould to build u a pool of considerable depth above the built. The suspension is delivered at such a rate that it overflows the rear wall 27 of the vat into an overflow compartment 28, from which it gravitates through a pipe 29' and can be recovered for recirculation through the pulp vat.

It is, of course, possible to change the construction of the various units, including the pulp vat, cylinder mould, and roving means, which enter into the combination hereinbefore described. So far as we are aware, how- 4 and to furl the ribbons directly on the mould into rovings. Not only does such a method make possible the production of high grade rovings, but the apparatus associated with the method is comparatively simple, compact, and inexpensive. The cylinder mould on which the ribbons are formed occupies very little space and yet permits the ribbons to under 0 all the steps necessary to the forma tion 0 high grade rovings, including the step of furling the ribbons directly thereon, where there is little chance for the ribbons to become weakened, torn, or snarled. Again, the cylinder mould itself may be sturdily built as to resist wear and tear over a long period by the action of the roving means.

What we claim is:

1. A method which comprises progressively depositing pulp fibers from aqueous suspension as continuous spaced ribbons on a portion of a rotating cylinder mould, and progressively furling the pulp ribbons into rovings on another portion of the mould.

2. method which comprises progressively depositing pulp fibers from aqueous suspension as continuous spaced ribbons on aportion of a rotating cylinder mould, progressively removing water from the wet pulp ribbons on another portion of the mould, and progressively furling them on still another portion of the mould.

3. A method which comprises progressively depositing pulp fibers from aqueous suspension as continuous spaced ribbons on a portion of a rotating cylinder mould, progressively removing water from the wet pulp ribbons on another portion of the mould, progressively detaching them from the mould, and finally progressively furling them on still another portion of the mould.

4. The combination with a rotary cylinder mould constructed to permit the progressive deposition thereon from aqueous suspension of spaced ribbons of pul of means for maintaining a constant supp y of pulp suspension in contact with one portion of the mould, and means for progressively furling the pulpribbons into rovings on another portion of the mould.

5. The combination with a rotary cylinder mould constructed to permit the progres sive deposition thereon from aqueous suspension of spaced ribbons of pulp, of means or maintaining a constant supply of ulp suspension in contact with one portion 0 the mould and a belt frictionally engaging another portion of the mould andarranged to be propelled at an angle to the direction of motion of the mould periphery.

6. The combination with a rotary cylinder mouldconstructedto permit the progressive deposition thereon from aqueous suspension 5 of spaced ribbons of pa] of means for maintaining a constant supp yof pulp suspension in contact with'one'portion of the mould, a

belt frictionally engaging another portion of the mould and arranged to be propelled at an angle to the direction-of the mould periphery, and means for maintaining the path of said belt fixed.

7. The combination with a rotary cylinder mould constructed to permit the progressive deposition thereon from aqueous suspension of spaced ribbons of pulp, of means for maintaining a constant supply of pulp suspension in contact with one portion of the mould, an endless belt one of whose stretches engages another portion of the mould and is arranged to be frictionally propelled at an angle to the direction of motion of the mould periphcry, and a roll-engaging the other stretch of said belt and arranged to be frictionally propelled in a direction opposite to the direction of motion of the mould periphery.

8. The combination with a rotary cylinder mould constructed to permit the progressive deposition thereon from aqueous suspension of spaced continuous ribbons of pulp and at least two separate chambers within said mould over which said mould successively passes, the first chamber being for the ap plication of suction to dewater the pulp ribbons deposited on said mould, and the second chamber serving as a reservoir for a compressed gaseous medium acting to lift the ribbons from the mould, of means formaintaining a constant supply of pulp suspension adjacent to the mould portion overlying said first chamber, and means for furling the pulp er serving as a reservoir for a compressed gaseous medium acting to lift the ribbons,

rom the, mould, of means for maintaining a constant supply of pulp suspension adjacent said first to the mould portion overlyin chamber, and means for furling t epulp'ribwbons into rovings on the mould portion immediately beyond said third chamber.

10. The combination with a rotary cylinder mould constructed to permit the progressive deposition thereon from aqueous suspension of spaced ribbons of pulp and a plurality ofseparate chambers within said mould over which said mould successively passed, the first of said chambers being for the application of suction to a portion of said mould to which pulp suspension may be supplied, the

second chamber being for the application of suction to the ortion of said mould immediately beyond he pulp suspension, the third chamber serving as areservoir for a com- 8 ressed gaseous medium actin to lift the ribons from the mould, and the ourth chamber being spaced from said third chamber and serving as a reservoir for a water supply acting to cleanse the mould from fibers be- 10 fore it again passes over said first chamber,

- or means for maintaining a constant supply of pulp suspension adjacent to the mould portion overlyin said first chamber, and means for furling t e pulp ribbons into rovings on 5 the mould portion between said third and fourth chambers and at which portion said rovings are delivered from said mould.

In testimony whereof we have afiixed our signatures. v

MILTON O. SCHUR.

WILLIAM B. MEGLITZ.

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