US66258A - George e - Google Patents

Description

@auch tars ganar @fitta GEORGE SELLERS, or SELLEESLANDING, iLLnvois. Lara-'s Paten.: No. 66,258, ma Juzg 2, 1867.

MACHINE POR DRESSING PAPER PULP.

@its Scintille maar in in ilpst tttas gstellt nur mating pmt nf tigt simu.

TO ALL WHOM IT MAY CONCERNr Be it known thatI, GEORGE ESCOL SELLERS, of Seller s Landing, Hardin county, in the State of Illinois, have invented certain improvements in Pulp-Dressers for Dressing or Cleansing Paper Pulp'or short vegetable libre from knots, motes, and other imperfections and impurities.

The object of my invention is to remove the knots in a more thorough manner than has heretofore been done, and at the same time to .cleanseV the pulp or bre of metes or specks that have a greater specific gravity than the pulp or fibre.

The nature of my invention consists in passing the diluted pulp or fibre into a pulp-screen iin such a manner that the motes or spccks, having a greater specific gravity than the pulp or libre, are collected intoa receiver, from which they can bc removed at any time during the operation, and in producing sucha motion ofthe pulp as to facilitate this object, and to present thev pulp to the screen in a line with the openings or slits of the screen in such a manner that as the pulp passes through the slits the knots or other imperfections too large -to pass through will travel on and be delivered from the screen while in operation.

To enable others skilled in the art to construct and use my invention, I will describe the mode in which I employ it, referring to the annexed drawing, making part of this specification, in which- Figure I is a drawingrin perspective.

Figure II is a sectional elevation- Similar letters having reference tp similar parts. V

Y A is E funnel-mouthed tube, through which the dilute pulp passes into the annular chamber B B, from which it is delivered through a series of openings, a a, into the conical chamber C, at the bottom of -which chamber is the `receiver D, provided with a valve, I, which is operated by the screw d. This valve is used to close the opening o1" passage between the chamber C and the receiver D, which receiver has anopeniug, e, through which it is filled; also a discharge` pipe, e', through` which the accumulated motes, specks, or heavy particles separated from the pulp are discharged. These openings are either closed or opened when required by plugsor valves. E is a passage from the conical chamber C into the pulp-screen F. This screen is of an inverted conical form, open at the top, and is supported within and by the frame I I. The screen is a continuous slit, s .s s, or opening from the inside to the outside', and from thebottom to the top of the cone; or it may be made of ringe' of metal that, when piled one onvanother, will form the hollow cone, the rings being kept apart the proper distance to leave the slit between them by partings or small pieces of sheet metal of the thickness the slits are required. The slit or slits s s s should be made wider on the outside than on the' face of the screen to give free passage to the pulp, and to prevent clogging. J. J' is a chamber, surrounding the conical screen in whichthe dressed or screened pulp is received, and from which it flows. through the tube K, regu- 1lated -by the gate L. M M is an annular trough, around the top of the pulp-screen `and chamber J J, to

receive the knots asV they are delivered over the top` of the conical screen, and from' which they are either removed by hand or run out through the spout N by keeping a stream of water running through-the trough M. O is a driving-pulley on the shaft P, on which shaft are hung two sets of agitators or iioats, Q Q. Q is within the conical chamber, and `Q within the pulp-screen. l

Having above described an apparatus such as I use, I will now proceed to describe the manner of operating with it. v

After Aclosing the discharge opening e', I fill the receiver Dthrough the opening e with water. When the receiver is filled and the openings closed, the valve b is opened, and` the shaft P, with the oats Q Q', is made to revolve by means of the belton the pulley O. Pulp from a stuit-chest, properly diluted, is then run into the funnel-mouthed tube A, being regulated in quantity by the stuff-chest valve or stud-pump, as the case may be, and as the supply of pulp is regulated to pulp-dressers in common use. The diluted pulp passes through the tube A into the annular chamber B B, and from that down intothe conical chamber C through the series of openings, a a. As-the chamber G'ills with pulp, and it ascends through the passage E into the conical screen 4F, it has acquired a-rotary motion from the action ofthe floats @which is kept up by the floats Q within the pulp-screcn, and inV this manner the dilute pulp is whirled round within the pulp-screen, travelling in the-direction of the slits or openings. Thebres of the pulp are sc presented to and slid along the slits that they pass into the chamber J J through much finer openings than can `be used in ordinary pulp-dressers. The amount of-pressure against the screen is regulated bythe velocity. The oats are made to revolve, and by the gate L, whiehregulates the flow from the chamber J J, and the level the dressed' pulp shall be kept at within the chamber J J, to produce'theproper amount of suction. As the dilute pulp is whirled around lwithin the screen it assumes a dish-like form, as represented by the red dotted lines in the drawing. The knots or imperfections too large to pass through the screen travel round and round until they are finally crowded over the top rim of the screen into the trough M M.

The' entire operation is very simple. The pulp, passing from the annular chamber B into the conical chamber C, has a downward current, impinging against the inside' walls of theconical chamber C. The tendency of all heavy particles is to slide down the walls into the receiver D, displacing the water, and gradually filling the 'receiver A knowledge of the quality of thc stuif that is being dressed, or a very little experience, teaihes how often and when it is necessary to clean out the receiver, which is done by closing the valve b and withdrawing the plugs e e', and running a stream of waterl through the receiver. The passage E is of 'comparatively large area, and the ascending pulp through it has a gentle? current, and without the rotary motion given by the iloats within the chamber C a large portion of the heavy particles would sink, and becollected in 'the receiver; but there are many metes and specks in paper pulp, differing but little in specific gravity from the pulp, that will pass through the screen and make unsightly blemishes in the paper. The rotary motion increases the distance the pulp has to pass in its ascent into the screen, not only giving the heavier particles more time .to sink,but giving a direction to the current more favorable than a direct upward current for that purpose; The rotary motion has also a tendency to draw the heavier particles to the centre or place of least motion. This is readily illustrated by partially vfilling a dat-bottomed vessel with dilute paper pulp, and mixing in it fine black sand, and then giving a rotary mbtion to the pulp suiciently rapid to make it rise on the sides and sink in th'e centre until the bottom of the vessel becomes visiblethrough the pulp, when the sand will be seen in arevolving cone in. the centre. When itbecomes necessary to clean the pulp-screen, first close the gate Lto prevent the4 escape of the water from the chamber J, run a stream of clear water into the funnel-tube A, and rapidly revolve the'iioats or agitators. All the water admitted is then whirled. around and dashed'over the top of the screen into the trough M. .After having thoroughly cleansed the inside of the knots that'may have become attached to it, open the gate L and allow the water to be dashed through the screen.

i Every practical paper-maker is aware that the pulp-dressers in common use are simply screens, separating by size alone, and that he `has to depend on sorting stock by hand, dusters, sand-screens, and other devicesfto free his stock from impurities that the pulp-dresser will not remove, and, with the greatest care, much escapes that causes blemishes in the nished paper. The pulp-dresser in most general use is a large screen of metal plates cut through' in iine parallel slits. The plates are fixed in a frame extending above andbelow the plates; the portion above to receive the dilute pulp, thattbelow extending into the vat4 that receives the screened pulp. By

l a. rapid up-and-down motion of the screen alternate suction and dashing are produced. The particles of pulp that happen to be over the slits are drawn throughl at every upward motion, and at every downward motion the slits are freed from the` knots that may have got over them. It must be evident to any o ne that with such a screen the heaviest particles must be the first to pass through. The knots are left dancing about on the face of the screen, and have to be scraped together and removed by hand." 'In 'scrapingl across the screen, knots are frequently pressed into the slits of the screen, so as to projectthrough tothe under side' and formv nuclei'to j collect other fibres, which, bythe 'rapid dancing motion of the screen on the pulp, are spun into'threads, that in time become detached and pass with the pulp on to the wire clothoi` the paper machine, and produce serious defects in the paper. The frame of the pulp-screen andsupporting bars of the plates also collect these strings. Bymy mode this serious difficulty is entirely avoided. There have been other devices to avoid this defect, but which have produced still greater. Pulpscreens have been made so as to have a horizontal oscillating motion on the surface of the pulp which passed upward through. the slits of the screen; but Vthis arrangement has-fthe objection of holding back knots and impurities in the pulp beingscreened until all in the vatA becomes so thick with knots as to impede the passage of the pulp through the screen', thus making paper of irregular thickness,

and obliging frequent stops to clean out the vat.

lWhen straw, cane, or other vegetable substances that yield short bre fit for paper stock are used, thc

separation of impurities by the difference-in the speciiic gravity is probably more important than for common rag stock. I find when using cane (Arundaaria macrosperma) that thehollows below the lower joints after the cane is cut are liableto collect' s an'd and dirt; also that sand is sometimes found in the cavities between the joints, carried up by the rapid growth of the plant; -also tha-t the joints themselves in a manner partake of the fibrous and non-fibrous parts of the plant, so united as to produce minute stick-like particles without the felting property of the pure cellulin, and that have a greater specific gravity than the fibres of the plant, andA yare readily separated from the br'e by my mode. I also iind that by subjecting the cane fibre to a cleansing by my mode, removing knots and other imperfections previous to bleaching, there is a large saving .intime and of chlorine, and aconse'quent saving in the expense of bleaching. l

From the above description of a machine capable of performing the uses to which I apply it, it is evident that the'theory of its operation is the'production oi' such motions or currents of the dilute paper p ulp'as to facilitate the settling and gathering together into a receiver of all particles having a'greatcr specific gravity than the fibres composing the pulp, and in presenting the pulp to bedrcssed to the screenl in such a manner and with such force as to make it travel in aline, or nearly so, with the slits or openings of the screen, and to constantly deliver the knots, or such imperfections as cannot pass through the screen, from the screen during the operation. It is also evident that the machinery to accomplish this may be made in various ways. For

instance, the" conical chamber C may be a cylinder, or of any other shape, and by giving it sucient depth it may itself lbe the receiver to gather the heavier particles; ortho receives may bc separated from the pulpscreen, and be used t'eny `point between the stuff-chest and the screen; or the screen may be made cylindrical and not conical; or the centre sha-ft with lits fleets may be mede stationery, end the screen medeto revolve.

I therefore do not wish to limit myself to the precise arrangement of machinery describcd,-wl1ile obtain the seme results by means substantially the sume. But what I (lo claim, and desire to soeilrc by Letters Patent, arel 1. I claim the' annuler chamber B B, through which the pulp is delivered into the chamber C, the chamber C and agitator Q'l to collect the heavy particles into the centre over the receiver D, Substantially es described arid for the purposes epeced. i

2. I also claim the pulp-screen F, with the slit or slits-s s s, the agiteter or oet Q tvo give direction tothe pulp in the line of the slits, the pulp-receiver J .l and regulating valve L, end the knot-receiver M M, all substantially es described and for the purposes; specified. Y

GEO. ESCOL SELLERS.

Witnesses:

PHIMP M. PRICE, COLEMAN SELLERs.

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