US1225198A - Pulp-screen. - Google Patents

Description

P. P. WESTBY.

PULP SCREEN.

Awucnlou man :uns 9.19m.

1,225,198. Patented May 8,1917.

3 SREETS-SIIEET l.

P. F. WESTBY.

PULP SCREEN.

APPLICATION man :un: 9. |913.

1,225,198. Patented Muy s, 1917.

3 SHEETS-SHEET 2.

IHI I1 www 3mm w wm P. P. WESTBY.

PULP SCREEN.

APPUCAHON fluo luna 9. 1913.

Patented Muy 8, 1917.

1,225,198- 3 www 3.

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FEDER P. WESTBY, OF PETERBOBOUGH, ONTARIO, CANADA.

PULP-SCREEN.

Specification of Letters Patent.

Application filed June 9, 1913. Serial No. 772,568.

To all whom it may concern Be it known that I, lrniin P. lVns'rnY, subject ot the King of Norway, residing at Peterborough, in the county of Peterborough, Province of Ontario, Canada, have invented certain new and useful Improvements in Pulp-Screens, of which the following is a specification.

My invention relates to paper making machinery and particularly to a pulp screen of the horizontal type, adapted to separate the tine librous or usable portion of the pulp from the coarse or unusable portion thereof.

The pulp screen forming the subject inatter hereof is of that type employing au annular perforated screen, within which is mounted a revoluble distributer` operating to discharge the pulp by centrifugal tendency against and through the screen.

The object of the invention is to simplify the structure as well as the means and mode of operation ot' such machines, whereby they will not only be cheapened in construction, but will be more ellicient in use, economical in operation, easily operated, readily ae. cessible and unlikely to get out of repair.

A further object of the invention .is to provide improved pulp feeding means whereby the rotary distributor will be supplied with the pulp equally throughout itsl circle of operation, whereby the entire screen surface may be utilized, thereby increasing the eiliciency and capacity of the machine.

Vith the above primary and other iuci dental objects in view as will more fully appear in the specification, the invenlion consists of the features of construction, the parts and combinations thereof and the mode of operation or their equivalents as herein after described and set 'Forth in lhe claims.

Referring to the drawings, Figure l is a longitudinal, vertical, .sectional view of the assembled machine. Fig. is a transverse, vertical, sectional viewon line .fr of Fig. l. 2l is a side elevation of the runner or distributer removed. from the machine. Fig. l is a detail perspective view of the screen supporting frame.

Lilie parte are indicated by similar characters of reference throughout the several views. j

In constructing the machine there is employed a main frame or housing, comprising oppositely disposed heads l and il, connected at their upper portion by an interposed water supply chamber or conduit 3 and at the lower portion by a base member 4, in which is formed a receiving chamber 5 for the screened pulp. This frame is provided with removable arcuate side members 6. These side members C may be secured in any desired manner, but in the drawings have been shown with dowels or studs 7 adapted to engage sockets 8 upon the base member l, and clamping members located about the peripheries ot' the heads l and Q. These arcuate side members (i in conjunction with the base member i form a substantially cylindrical housing or casing.

Removably supported in a concentric position within the casing or housing is an annular screen plate 1l). This screen plate is preferably divided into a plurality of arcuate sections, each supported upon a frame member comprising longitudinally disposed angle bars l1, connected by arcuate ribs 12. ln order that the screen surface may be as little obstructed as possible, the. arcuate ribs l2 of the supporting frame, are spaced away troni the screen plate 10 as shownin Figs. 2 and l. The end` of the screen plate l() is secured lo the longitudinal angle bars 1l, while the medial portions of the plate are supported on bosses or lugs 13. projecting inward from the arcuate ribs 12.

ln order to obviate the liability of breakage oi' the screen platedue to the great pressure and strain to which it is subjected, the central portions of the plate are rendered resilient or slightly yielding by forming the bosses or lugs 13 of rubber or other resilient material. lt is to be understood that the resiliency ot the screen plate is not essential. but under certain conditions is desirable. Helical springs may be substituted for the rubber supports. ln lieu of the resilient bosses 13, such bosses or supports may be formed integral with the arcuate ribs 12. ln the event that the bosses are formed of a resilient matter. a second resilient collar or washer li is preferably located on the inner side of the plate and the screen plate and collars are. secured to the arcuate ribs l2 by means of a conical headed bolt 15. In the event that solid, integral bosses 13 are employed, the second resilient collar Patented May 8, 191'?.v

CAT

may be omitted and an ordinary metallic washer employed instead.

The conical head of the bolt 15 affords no place for the lodgment of the fibrous particles of pulp and serves to direct such portions of the pulp as may strike the bolt head onto the screen plate. The sectional screens and frames thus formed may be bolted one to the other, but are preferably secured by means of clamps 16 which engage the radial flanges of the angle bar 11. The screen plates and frames are supported upon annular flanges 17 upon the inner face of the heads 1 and 2. The lower portion of the heads 1 and 2 are provided with a second inward projecting [lange 18 parallel With the flange 1T to form an intermediate groove within which the lower portion of the screen plate and frames engage. The sectional screen plate may be readily removed for inspection or replacement by the removal of the arcuate side members 6.

Journaled in suitable bearings 19 upon the heads 1 and 2, is a longitudinal shaft J0 carrying at one end a drive pulley 21. 'lhe shaft is located concentric with the screen plate and casing. Projecting inward from the head 2 and concentric with the shaft 20, is a` pulp feeding chamber 22. This chamber comprises a circular stepped housing, the successive steps being concentric one with the other, and of sufficient difference in relative diameters to permit pulp feeding ports or orifices 23 in the transverse face of each successive step. By reference to Fig. Q, it will be seen that these ports or orifices Q3 are of different relative sizes according to their height. It will be noted that the ports or orifices adjacent to the top of the feeding chamber are much larger than those at the bottom thereof. The pulp discharged within the screen plate will tend to settle or concentrate in the lower portion thereof. by the influence of gravity. This is to some extent compensated for, by the variation in the relative sizes in the ports, whereby a larger portion of the pulp Will he discharged into the upper portion of the runner or distributer. The variation of the relative sizes of the port further compensates for the difference in pressure or head.y under which the pulp is discharged to the higher and lower orifices.

rThere is formed in the head 2 an annular chamber or recess Q4, communicating throughout its entire extent with the feeding chamber This annular chamber or recess is provided with a pulp inlet 25. The pulp entering through the inlet tills the annular recess 24 passing thence into the feeding chamber 22, from which it is discharged in a longitudinal or axial direction through the ports or orifices Q3.

Secured upon the shaft 2O adjacent to the feeding chamber 2Q, is a hub 26, by which are carried a plurality of radially disposed wings or Yanes 27, forming the runner or distributor. These wings or vanes project radially to points adjacent to the annular screen plate and extend longitudinally throughout the width of the screen plate. The wings I( oYerh-ang the feeding chamber and are notclual or recessed to correspond with the successive steps thereof. It is to be noted that each shoulder or ol'l'sct of the wings 2T. extends inward beyond the orifices or ports 112i of the corresjmndine' step ofthe feeding chamber inasmuch as the terminal port or orifices of the feeding chamber 2; are located closely adjacent to the shaft 2t) and the internualiate sparc between successive wings or Yanes is contracted in such close proximity to the hub QPL alternate wings an` recessed or cut a way adjacent to the last tace or step of the feed ing chamber. as shown at :Inl M' their outer end the uings or Yanes 2T are connected one with the other by the annular rim 2th surrounding the feeding chamber "22. The wings` are I'nl'thcr supported and connected one with the other. by a trans- Yorsc web ill, extendingl adjacent to the periphery ot| the runner or distributcr. and substantially diriding the chamber of the machine into two compartments communirating one with the other through an annu lar opening about the periphery of the web, adjacent to the screen plate. Beyond the web il() or in the second compartment the wings or Yanes 27 are pif-ejected longitudinally as at 3l. to overhang an inward annular projection carried by the head 1 and provided with a peripheral flange forming an annular channel An outlet 35 for the tailings and coarse or unusable portions of the pulp` leads from this channel through the head l.

water supply conduit 36 leads to the water chamber El which is provided with a plurality ot jaifoi'atioiis adapted to disA charge water in a spray upon the screen plaie l0. branch conduit 3T discharges a stream of water into the annular channel Ell to wash the tailings which are collected therein througli the outlet 35.

rlhe Yanes ai", in addition to being radially disposed about the huh t), are inclined somewhat to the axis of rotation as clearly shown in Fig. 3. The portion of the Yanes 27 overhanging the feed chamber 2Q. is inelined in a forward direction while the extremity 3l is located slightly to the rearwardn in relation to 'the direction of rotation. This causes the pulp discharged. from the feed chamber QQ. and which is carried outward or radially by centrifugal tendencies to gradually travel throughout the length of the vanes or wings. The finer and usable portions of the pulp will be dis charged radially by centrifugal tendencies against and through the perforated screen plate l0, into the annular chamber intermediate the screen plate and the cover scction o, through which chamber the screened pulp Will pass to the receiving chamber 5, located in the base of the machine. From this chamber 5 the usable, pulp is discharged through an outlet 38. The heavierl and coarser portions of' thc pulp will gradually travel longitudinally upon the blade or wing, due to the inclination of such wings to the axisl or rotation, while at the same time they will be moved outward under centri tugral tendencies. The unusable portions of the pulp will finally pass the periphery ot' the We) 3() and will be discharged from the ovcrhanging portion 31 of the vane into the annular channel 34, from which they will be flushed by Water from the branch conduit 3T and finally discharged from the machine through the outlet Located upon the rear side of each of the wings or vanas 2i'. adjacent to the cdjre thereoic and parallel with the perforated screen plate l0, is a longitudinal flange or ledge 39, formingi a recess lll innnediately beneath such ledge. As the runner or distributor rotates at a very high rate of speed, the tendency will be to forni a partial vacuum within the recess Ul immediately barl: of cach Wing'. This partial vacuum will create a suction upon the screen plate 10, tending to free it from the coarser particles ivhich find lodgment thereon, drawing' such particles away from the screen and again into the influence ot the blades or vanes 2T, upon which such particles will move longitudinally a limited distance before being again projected upon a screen. 'Thus such coarse particles are repeatedly projected from and returned to the influence of' the wings or vanes until every particle ot line or usable material is separated therefrom by which time the coarse particles have traveled beyond the transverse web I3() and are deposited by the extension 3l in the waste or tailing channel 34.

lt to be noted that the outer edges oi the ports 23 are flush with the walls of the feeding chamber 22. Thus there will he no obstruction to the free discharge of the pulp from the chamber and no tendency l'or the heavy portions of the pulp to settle n'ithin the feeding;V chamber 22 and remain therein. The otlsets or shouldered portions ot' the ninos or vanes by extending entirely across the ports 23 and closely adjacent thereto, create a suction upon the feeding chamber, which serves to draw the pulp through the ports and into the distributer. This action of the distributer assists in preventing the pulp settling within the feeding chamber and accelerates the fionT of pulp therethrough.

From the above description it will be apparent that there is thus provided a device ot the character (inscribed, possessing the particular features of advantage before em1- merated as desirable, but which obviously is susceptible of modification in its form, proportion, detail construction or arrangement of parts, without departing :from the principle involved or sacrificing any of its advantages.

lVhile in order to comply with the statute, the invention has been described in language more or less specific as to certain structural features, it is to be understood that the invention is not limited to any specific details, but that the means and construction hcrein described comprise but one inode of putting the invention into effect, and the invent-ion is therefore claimed broadly in any of its possible forms or modifications uithin the scope of the appended claims.

llaving thus described my invention, I claim,

l. ln a pulp screening' machine, a casing', a screen member, a stepped feeding chamber projectinev within the casing, said member having disehalga'e ports iu the transverse fares of' succeedingv steps, and a rotary distributer within the casing. the blades ot which have stepped notches therein conforming;` to the contour ot' the feeding' chamber which they overhang.

ln a pulp screeningv machine. a casing. a screen member. a rotary distributer therein` a `feeding chamber projecting within the casinar in a position concentric with the distribnter and ha ving pulp discharge ports located in different vertical planes substantially ]n rpendicular to the axis of rotation of the distributer.

ln a pulp screening machine. a casing, a. screen member, a rotary distribnter. a fccdiney chamber projecting into the distributer in a position concentric therewith, said feeding; chamber having pulp discharge orifices located, at dillicrent distances from the axis ot rotation ol the distributer and in ditlerent planes substantially perpendicular thereto.

l. ln a pulp screening machine, a casing, a screen member, a rotary distrilnlter, a stepped feeding chamber projecting within the casina'. said feeding chamber having pulp discharge ports in the transverse faces oi succeedingr steps.

ln a pulp srivccninnl machine, a casing'. a screen member. a circular Vfeeding chamber projecting within the easinggr concentric with the distrilgnlter and having concentric pulp discharge ports in the transverse tace thereof and coincident with the peripheral Wall of the chamber, and a rotary distributer.

(i. A pulp screening n'iachine. a` casing, a screen member. a recessed rotary distributor therein rotatingr on a horizontal axis, a concentric ecding chamber extending Within the recess of the distributer, and a series of ports in said feed chamber discharging in an axial direction and located in different planes throughout the axial length of the distributer.

T. In a pulp screening machine, a casing, a screen member, a rotary distributor therein rotating on a horizontal axis, a feeding chamber projecting within the casing having a plnralitv of arcuate pulp discharge ports therein. said ports varying in length accordingto their relative locations, the uppermost ports being larger than the lowermost ports.

S. ln a pulp screening machine` a casing, a screen member. a rotary distributor therein. a stepped feeding chamber, a plurality ol` pulp inlet ports in the llat faces of each step, said ports of tach step being of differoui areas in inverse proportion to the head or pressure under which the pulp is discharged through the individual ports.

9. ln a pulp screening machine, a casing, a .screen member, a stepped feeding chamber projecting within the easing. haring pulp discharge port.- located in ',lillerent planes in the transrerse fares thereof, and a rotary distributer recessed lo conform to the contour of the feeding chamber.

l0. In a pulp screening machine, a casing, :i stepped feed chamber projecting within the easing having pulp discharge ports located in dilferent planes in the transverse faces thereof. and a rotary distrilmter, having a plurality of substantially radially disposed blades, each of the blades being adapted to extend inn'ard toward the axis of the distrihuter beyond the pulp discharge ports.

1l. lu a pulp screening machine, a casing, a screen member, pulp feeding means, a rotary distributer rotating on a horizontal axis comprising a plurality of substantially radially disposed blades, a transverse web connecting said blades and extending beyond the radial position of the pulp feeding means. said web dividing the casing into tn'o compartments communidating one with the other about the peripheli'y of the Web, and an outlet conduit for tailings leading from one of the compartments.

l?. In ar pulp screening machine, a casing, a screen member, pulp feeding means, a rotary distributor comprising a pluralityv of substantiallyv radially disposed blades inclined to the axis of rotation, a transverse web connecting said blades beyond the periphery of which said blades extend, said blades being correspondingly inclined at opposite sides of said web whereby heavy particles of pulp will he induced to travel toward said Web beyond which they are deposited by the action of said blades.

13. In a pulp screening machine, a casing member, pulp feeding means, a rotary distributer within the casing and an inward extension on one end of the casing having an external peripheral channel therein adapted to receive the tailings.

14. In a pulp screening machine, a casing, a screen member, pulp feeding means, an inward extension projecting from one end of the casing and concentric therewith and having a peripheral channel therein, and a rotary distributer having a plurality of substantially radially disposed blades overhanging the annular channel.

15. In a pulp screening machine, a casing, a screen member, pulp feeding means, a rotary distributor having a plurality ot' substantially radially disposed blades, each blade having on its rear Side in relation with the direction of the rotation. a longitudinally disposed rib located adjacent to the edge of the blade.

16. In a pulp screening machine, a easing, a. screen member, pulp feeding means, a rotary distributer having a plurality of substantially radially disposed blades and means to induce a suction upon` the .screen .member in the rear ol each bla dc to clear the screen member of adhering particles.

17. In a pulp screening machine, a casing, a screen member, a pulp feeding means, and a rotary distribute-r comprising a plurality of tangentially arranged blades, each blade being inclined to the axis of rotation.

18. In a pulp screening machine, a horizontally disposed cylindrical casing, a cylindrical screen member concentrially located within the casing, a horizontal shaft in axial alinement with the casing and screen member, a stepped circular horizontally disposed feeding chamber extending Within the casing concentric with the shaft, said feeding chamber having pulp discharge orifices in the, vertical faces of each succeeding step, and a rotary distributer carried on the shaft adjacent to the feeding chamber.

19. In a pulp screening machine. a horizontally disposed cylindrical easing.` a cylindrical screen member concentrically located within the casing, a horizontal sha tt in axial alinement with the casing and screen member, a stepped circular horizontally disposed feeding chamber extending Within the casing concentric with the shaft, said feeding chamber having pulp discharge orifices in the vertical faces of each succeeding step, the area of those discharge orifices beneath the level of the shaft being less than that of those above the level of the shaft, and a rotary distributer carried by the shaft.

20. In a. pulp screening machine, a horizontally disposed cylindrical casing, a cylindrical screen member concentrically located within the casing, a horizontal shaft in axial alinement With the casing and screen member, pulp feeding means leading to the casing, a rotary distributer carried on the shaft, a concentric annular extension projecting inward from one end of the cylindrical cas- .l (Mi lili ing ,and having a peripheral {iange forming a vertically disposed annular' channel about said extension to receive the tailings.

21. In a pulp screening machine, a horizontally disposed casing, a cylindrical screen member eoncentrically located within the easing, a horizontal. shaft in axial alinement with the casing and screen member, pulp feeding means leading to the casing, a rotary distributer carried by the shaft, comprising a plurality ot' substantially radially disposed blades, each blade being projected raarward adjacent to its Aedge to form a recessed rear face.

Q2. In a pulp screening machine, a easing, a cylindrical screen member therein, a supporting frame for the screen member, including annular ribs of diilerenl` radius than that of the screen member, bosses located at several points upon the ribs with which the` screen member is engaged and by which the screen member will be spaced zlvvay from the supporting ribs, and a rotary distributer.

In a pulp screening machine, a easing', a cylindrical screen member divided into arcuate sections, a supporting frame for each of the sections comprising parallel arcuate ribs of di'erent radius than that of the screen member, transverse bars connecting the arcuate ribs, and projections carried at spaced intervals by the arcuate ribs With which the screen member is engaged, whereby the screen will be spaced away from the ribs.

24. In a pulp screening machine, a casing, a cylindrical Screen member divided into arcuate sections, a supporting frame for each of the sections comprising parallel arcuate ribs of dilerent radius than that of the screen member, transverse bars connecting the arcuate ribs`r and resilient supports interposed between the screen member and the ribs.

In testimony whereof, I have hereunto set my hand this` 27th day of May, 1913.

FEDER P. VESTBY.

Witnesses:

OLIVE IRWIN, y J. E. L. GOODWILL.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.

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