US2083341A

US2083341A - Tube roll mechanism for paper making machines

Info

Publication number: US2083341A
Application number: US49469A
Authority: US
Inventors: William C Nash
Original assignee: MARIE DUVALL NASH; ROY A NASH; WILLIAM M NASH
Current assignee: MARIE DUVALL NASH; ROY A NASH; WILLIAM M NASH
Priority date: 1935-11-13
Filing date: 1935-11-13
Publication date: 1937-06-08
Anticipated expiration: 1954-06-08

Description

' `lune 8, 1937. w, CLNASHy TUBE ROLL MECHANISM Foa PAPER MAKING MACHINES Filed Nov. 13, 1935 2 Sheets-Sheet l kwh@ June 8, 1937. w. C NASH n TUBE noLL MECHANISM FOR PAPER MAKING MACHINES 2 Sheets-Sheet 2 Filed Nov. 1 5, 1955 APatented June s, 1937' PATENT OFFICE TUBE MECHANISM EOR PAPER MAKING MACHINES William C'. Nash, Neenah, Wis., assigner of oncfth to Mary Jones, Neenah Wis.; one-i'th to William M. Nash, Chicago, lll.; one-lth to Roy A. Nash, New Rochelle, N. Y.: and one- 'ilfth to Marie Duvall Nash, Neenah, Wis.

Application November .'13, 1935, sentano. 49,469 .2 Claims. ((21.l 92-44) This invention relates to improvements in paper maidng machines and refers specically to an improvementin'the tube rolls of a paper making machine of the Fourdrinier type.

5 In the making of paper on a Fourdrinier type oi' machine, the pulp 'predominantly liquid, is discharged from the head box onto a moving wire or screen. 'I'he wire or screen passes over a series of tube rolls which contact the lower face of the screen and assist in tion of the wire. The tube rolls are usually of relatively small diameter and are rotated by` their contact with the moving screen.

Of course, since the tube rolls are rotated by their contact with'the screen, the -peripheral speed oi' the surfaces of Vsaid'rolls will be substantially equal to the speed of travel of the screen and the angular velocity of said rolls will 20 depend upon thespeed of travel of the screen and the diameter oi' the rolls. When operating the paper making machine at low speeds, the screens, of course, travel at relatively low -speed 'and hencethe rollsare not rotated at an ex- 25 cessive angular velocity. However, as the speed ofv travel of the screen increases, thereby increasing the angular velocity of the rolls. diiiiculty is encountered due primarily to centrifu.

gal action oi the rolls upon the liquid carrier of 3 the pulp which seeps through the screen onto the rolls, and also upon the fact that the front sides oi' the rolls travel upwardly toward the screen and the rear or trailing sides of the rolls travel downwardly and away from thescreen.

5 'I'hese phenomena, although present at all screen speeds, are accentuated at high speeds and tend My invention is specifically directed to the;

elimination of this diiiiculty and resides broadly in the provision of means for decreasing the rate 50 of rotation oi'- the tube rolls, particularly those adjacent the head box. vIn other words, by the invention. one of the above mentioned factors which cause disturbance of the iibers upon the screen is eliminated.

f 55 'In reduce the speed of said tube rolls that the removal of the liquid from the pulp carried upon 'the upper poris, to render the speed of the tube rolls independent of the speed of travelof the. screen, I provide an arrangement whereby the axes of the 'tube rolls can be moved at a desired rectilinear speedlin the direction of travel of the screen. 5' By correlating the speed of translation of the'` rolls with the speed of translation of the screen theV rolls can be-caused to rotate at-a peripheral speed substantially equal to theI diierence ofY said speeds of translation. .This ldierence inv 10 speed may be either positiveor negative, that is,

if the speed ofv translation of the screen exceeds the translation speed of the rolls, the rolls will rotate at a peripheral speed, equal to the dif- Y ference, in the direction oftravel of the screen, or if the translation speed of the rolls exceeds u the speed of the web, the rolls. will rotate in the opposite direction to the direction oi' travel of 'the screen. However,g in controlling the rate of rotation of the rolls, as described, the ultimate function oi' said rolls, that is, to assist in the removal of the liquid carrier, is in nowise diminished.

Other objects and advantages vof my invention will be apparent from the accompanying drawings and following detail description.

In the drawings, Fig. 1 is a fragmentary side elevational view, partly inv section, oi' a portion of a paper making machine, illustrating particularly an embodiment of my invention as ap- '30 plied to the tube rolls. A

Fig. 1a is a continuation of Fig. 1, illustrating the detlectors between some of the tube rolls.

Fig; 2 is a diagrammatic detailed view, illustrating the disruptive action oi' a conventional tube roll upon the paper web.

' Fig. 3 is a sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is an enlarged fragmentary. detailed sectional view, illustrating the use of the defiectors which lcomprise an embodiment of'my invention.

Referring in detail to the drawings, I indicates one of two oppositely disposedside frames which may be positioned on opposite sides of la portion of the wet end Aof a paper making machine 2.

A hanger 3 carrying an open bearing 4 is mounted upon an end of each o1' the frames I in which opposite ends of shaft 5 are journa-iled, said shaft v carrying breast roll 6. A Fourdrinier wire or screen Tpasses around breast roll 6 in the convention'al manner and travels in the .direction indicated by the arrow. v

A sprocket vwheel 8 may be mounted upon each Side of the machine 2 adjacent the breast roll 6 55 -70 quantity of pulp Il.

g over which'each of the chains passes. Sprocket 'chains 0 at the upper portion of their travel move A in vdirection as screen 1,' either wheels lor Il constituting the 4driving wheels. Howevtl'. the drivingof the sprocket wheels is independent ofthe driving of screen I-and; as will there will be relative motion `between the two.

Each of the chains l carries spaced brackets Ii chains. the brackets upon opposite chains'being in transverse alignment.l A tube roll i2 may be carried between each pair of aligned brackets ii, said rolls each having oppositely projecting stub -shafts I3 which may be Journalled in the respective brackets Ii. v e

A track structure il is mounted upon each the framesi below the path oftravelof screen 1, said structure being secured -to said frames by .means of bolts Il or the like. 'lhe track structure il is oval shaped and traverses the path of travel of the chain 0. The inner face of each oval track structure is provided with a recess Il which also defines an` endless oval pathsimilar 'niscarrieaoneacn'stubshaft n enamora diameter slightly lessthan the width of the reby rolls i! and the weight ofjsaid and @insteadofbeingcarriedby carried by the track, structure I0.` hereinbefore described. chains s areadaptedtobedriveninthesamedirectionas Y in view of the Afact that screen 1 contacts the surfaces of said rolls and thereby 50 rotates said rolls. the peripheral speed ofthe rolls will be substantially equal to the difference (either mi! pressure of the pulp causes averita'ble cataract Mxucmd through thescreen adiacent the headA In rig. 2 a diagrammatic view-of a conventraveling at a rapid rate, the head of pulp Il in headbox Il mustberelativelygreatin order that the proper amount of pulp be deposited upon the wire. Another result of the rapidly moving screen 75 i'l' is that roll il and the remaining tuberolls 111,088,841v l (not shown) are revolved at a terrific rate. As I be hereinaftermore fully described. the speed.i of the chains I and screen 1 isfdifferent so that which may be mounted upon of the to the loci of the chainU A ball-bearing. roller at thefupper portion of travel ofsald' the head box which Adisclial'gd the screen decreases below a critical moving'screen-with sumcient pulp. This thosetuberollswlthinsixorelght feetfrom breastrolluponthemovingchaim has been hereinbefore described.- the of the pulp 20 in the head box drives the liquid carrier and portions of the pulp through the screen in a cataract, as indicatedby the arrows at Il.'

In -addition. for a considerable period of travel l' of the screen the pulp upon the screen dehydrates at a rapid rate, the liquid carrier showering through the screen. A portion of this liquid is. carried upon the surfaceofthe rapidly rotating tube rolls and by centrifugal'force is thrown from the roll at a rapid rate in the direction of the resultant of the radially acting centrifugal force and the tangential force, which latter is a result of centrifugal force and the phenomena of surface tension which causes the liquid to adhere -suillciently to the surface ofthe roll to have tangential motion imparted to it when it is thrown from the roll. This action of the tube rolls builds up a pressure sone at 22; that is, adJacent the advancing side ofthe roll Il, and a reduced pressure sone 2l adjacent the receding side of the roll'. The pressure in the zone 22 tends to lift the fibres from the screen surface and otherwise Adisturbs the original desired lay of the libres. The 'reduced pressure zone 23 tends to suck the nbres. d own upon the screen surface which tends to impartan objectionable wire mark upon the paper. v In addition. pin-holes'are formed and a one-sided shade is imparted to colored paper. Consequently. the tube rolls of the conventional paper makingmachine constitute one of the most serious limitations to the speed of the machine.

It can readily be seen therefore, that by con- A trolling the rate ofrotation ofthe rolls i2 independent ci thespeed of the screen 1. the dimculitherollslfwillbesorotatedastohaveaperipheral speedofwfeetperminuteinaclockwise or positive direction and in the latter case the rollswillhaveaperipheralspeedofwfeetper minute in a coimterclockwise or negative direcabove tion.

rnview ofthe-racetmtnemmmmymmm `iacenttherolls,thedisruptiveeffectoftherapid lyrotatingrollswillnotbe'aspronounced the rate-of dehydration of 'the instance, it may be found suiiicient to mount However, invention broadly contemplates motmtingall numberlessthanalluponamovingcarrien@ Asthescreenprogressesoverthe tablecrr rolls. the web upon thescreen loseswater diminishingrate andeventhoughthetube .arerota'ted atarapidrate,the`mass ofliquid volvedvdoes not a disturbance of the s tion. '0f course,any'desired diuerence ofscreenv orchainspeedmaybeadoptedandthe exampleisnottobeconstnxedasalimita I contemplate mounting, in any convenient manner, bams plates or deiiectors 24 between th'e vrolls si which latter may comprise the usual tube rolls with laterally immovable axes. The bailies or de` ectors may be T-shaped in section with the stall oi the T vertical and between adjacent rolls and the cross-portion of the T horizontal and adjacent the lower race of the screen. With this arrangement the pressure and vacuum zones -will be broken up and the liquid thrown by centrifugal force will not be permitted to injure the web.

The baes N, oi course, could be used between adjacent tube roll oi' the conventional paper making machine and in themselves would reduce the injurious eect o! the rotation of the rolls.

Reverting to the chain mounted rolls, it will be noticed that, inasmuch as the rolls rotate freely, there will be no undue friction between the screen undersurface and the rolls, as would be the case were the rolls stationary. This, of course, preserves the life of the delicate, relatively expensive screen.

It is to be understood that, the carrier for the rolls i2 need not necessarily be a sprocket chain, since my invention broadly contemplates lateral movement of the axes of the rolls l2 by any means stance, to prevent the excessive passage of illler through the screen, the chains may be driven at l a linear speedin excessror the speed of the screen whereby the rolls l2 will be rotated in a counterclockwise direction. Broadly, myinvention contemplates both methods of operation.

I claim as my invention:

v1. In combination, a paper making machine comprising a frame, an endlessly moving paper forming'screen carried by said frame, a plurality of rotatable tube rolls over which said screen moves and upon which said screen is supported,

a conveyor ior moving said tube rolls laterally in a plane parallel to the plane of motion of said screen, said frame being provided with a channel opening towards, and on each side of said conveyor, said channels paralleling the path of travel of said screen, a bearing carried at each end oi each of said tube .rolls adapted to travel in said channels whereby movement of said tube rolls at right-angles to said channel is limited.

2. In combination, a paper making machine comprising a frame, an endlessly moving paper forming screen carried by said frame, a plurality of rotatable tube rolls over which said screen moves and upon which said screen is supported,

an endlessly moving conveyor for moving saidA tube rolls laterally in a plane parallel tothe plane of motion of said screen, said conveyor over said sprocket wheels, a bearing carried at y each end of each of said tube rolls adapted to .travel in said channels whereby movement of said tube rolls at right-angles to said channels is limited,

WILLIAM C. NASH.