US2694345A - Water removal device for paper forming wire - Google Patents

Description

Nov. 16, 1954 HQRNBQSTEL 2,694,345

WATER REMOVAL DEVICE FOR PAPER FORMING WIRE Filed Jan. 7, 1950 (O o 22% 28 9%; 51 3/ M JZH-I/EHZLUT' Unite States Patent 6 WATER REMOVAL DEVICE FOR PAPER FORMING. WIRE.

Lloyd Ho'rnbostel, Beloit, Wis., assignor to B'eloit Iron Works, Beloit, Wis'., a corporation of Wisconsin ApplicationJanuary 7, 1950, Serial No. 137,377-

6 Claims. (Cl. 92-44) The present invention relates to a water removal device for a paper machine forming wire and more particularly to a device positioned within the loop of a paper forming wire for removing excessive moisture from the under surface of the wire.

In conventional Fourdrinier-type paper making machines, a dilute solution of paper stock is caused to flow onto a foraminous forming wire, excess water being drained through the wire to deposit thereon a layer of stock fibers. During initial water removal, i. e., immediately after the stock has been introduced onto the wire, the wire is conventionally supported by a plurality of spaced table rolls and free water drainage occurs through the wire. Subsequent Water drainage is facilitated by suction b'oxes disposed within the wire for subjecting the undersurface thereof to sub-atmospheric pressures so that a differential air pressure advantage is gained to aid in water removal.

The present invention now proposes the employment of an additional device along theweb forming or upper wire run in advance of the suction boxes to aid in the removal of Water throu h the wire. The present device thus prevents the flooding of the initial suction boxes by the large quantity of water initially removed from the stock and .thus makes possible the more efficient removal of water;

Tn general. the device of the present invention comprises an endless belt. which is trained about a supporting structure. such as a plurality of rotatable rolls. to directly underlie the upper run of the paper machine forming wire. The belt has its upper run traveling in'the same direction as the u per run of the overlving forming wire and is preferablv moisture and air im ermeable so as to facilitate water removal. The oncomin upper run of the belt preferablv contacts the under surface of the forming wire while-the offaoing or downstream portion of the upper run is inclined downwardly away from the forming wire. The separation of the traveling belt'from the wire creates a redu ed pressure area directly underlving the formin wire. This reduced pressure area efiectivelv increases the differential pressure u on the upper surface of the forming wire to aid in the draina e of moisture from the forming wire and the web positioned thereon.

Moisture drained throu h the wire onto the belt is thrown therefrom bv centrifugal force and a deflector is provided to underlie the forming wire in order to prevent the water from being thrown a ainst the undersurface of thewire. An additional deflector is preferably provided in advance of the belt to remove excessive moisture from the underside of the wire. The belt mav be independentlv driven or driven by contact with the forming:.wire surface.

ltis, therefore. an im ortant obiect of the present invention to provide an improved water removal 'device for a aper machine formingwire.

Ano her im rt nt nhiect of the e ent invention is to pr vide n i o d w ter remov l i e for a a er forminc'wire. incl ng an i permeab e, h ('nnfnnfinq the nnrlersu f re f he-Wire for a D rtinnn in; run and The" seo raterlthe efrom alrmq'a dn mnardlv inclined path to form a redu ed-pressure area direotlv underlying the ire to aid the dr ina e of mois re therefrom.v

Tt is a fur her im ortant ohiect of thepre ent invention'to pro ide an improved W er r ov l device for a.-pa.oerm hi e forming wire inolndinq a continu us impermeable belt trained about a plurality; of guide rolls,

theibeltfinitially contacting the .undersurface' EOfthecwiren and subsequently being. removedfrom COIltflCLrthCl'CWith to createua: suction ..area directly underlying -.the forme ingtwire to facilitate .thedrainage -.of .water therefrom.

Still another important object; of the present invention t. is. .to 1 provide; an. improvedv water removal device. for a looped .foraminous belt including. an impermeable belt; closely underlyingtthe.foraminousbelt within. the loops thereof for creating .a .pressure differential effectiveuto-t facilitate drainageuof .water .from. the-.foraminous. belt; and .for :throwingthe removedwater: adjacent ;a :deflector which .preventsre-wettingof .the foraminous .belt or maze terial thereon.

Yeta further important object ofthe present invention; is. to provide ;a .method;.for:;thel zremoval'. OfiQWaIGIYEfIZOITUZ a forming nwire. by. creating ;a differential .zpressure rarea .l underlying the. :wire,:,draining .:water:;through;ithe .wire. into a the area, and flingingswater,frometheaareac Other and..- further. :important; objec of: [.thlSeglIlYCIlfiQl'l will be'aapparent rfronrthe disclosures: in :the: specifications and.theaccompanyingdrawings};

Onthe drawingsr;

Figure, 1 'is a fragmentary schematic, view. illustrating; a water removal device of the.present-invention;

Figure "2 isa fragmentary-schematic view .similar .10.: Figurel illustrating a modifiedtform-ofra.water ;re rnpyal-.; device of the-present invention;

Figure 3. is a schematic. illustrationsofethe. wet.;-end .of. a vFourdrinier type-..'papermaking; machine employing ,a waterremoval device 'ofv Figure 1;; and,

Figure 4-is a .;sectional view .takengalong the; plane,-; IV-JV of Figure 2.;

As shown .1011 the drawings 1.

In Figure; 3, reference numeral .101 refers: generallyfltoa a Fourdrinier-type paper making machine including, a: looped forming wire 11 trained about ,a br.east roll .12 and a :couch roll 13f A-conventional stock 'inlet;.box.-. 14- is provided to introduce a pulp suspension onto-.the. upper run of theformingwire 11,.the undersurface. of: the first reaches of the .wire being supported by a .plu-g; ralitvof table rolls 15 and the edges of the :web formedri on thewire being defined by conventionaldeckle-straps- 16. A-plurality ofsuction boxes-1'7 are provided-for facilitating the removal of water from the wet. web-z supported by the wire lladjacent the couch roll -13 A water removal device of the-present invention -is-- located .to underlie the-reach .of the .wire. 11 .betweenthe;- table rolls -15 andthesuction boxes 17. this devicebeing generally indicated by reference numeral 20;

As shown in Figure 1,- the device.20.includesanendless belt, preferably formed of airand'water im ermeable: material, such :as rubber sheeting. hea ilv. sized-fabric.- a-t ti htly woven felt,'or the like,;and the belt is of sufiicient; width to-extend across the-widthof.the-rformina e ire..-; The belt 21 istrained about a first lar-ae guide rolli22gands a second relatively small guide-roll '23 so that theinitiah or oncoming-reach'21aof the.belt 21 contacts the under: surface ofthe forming wire 11.5.

Afterpassage of the=beltllrover the 'auide. rollv 23. the belt istrainedabout an additional large. guide ml; 24 rotatable about an axis parallel to but downwardly. displaced from the axis of the roll 22, so that asecondary otfgoina reach ZIbofthe belt21 is inclined away-from the under surface of -the.wire 11. A return reachy21c of'the belt.from :the.guide roll 24-to theinitialii uidei roll 22'is -deflected by means 'of a tensionroll 25.,outside.--. the loop of the belt: The roll 24' is adiustable:vertically;.- to change-the inclination of the .belt reach- 2.l.b.withrespect; to the wire 11,- andthe tension'roll 25 isadjustable :ver-y ticallyto vary the;tension upon the reach 210 of the belt-.;;

Operation of the device will be appreciated from the; fact-thatthebelt 211is-preferably impermeableto air.- and moisture,;while the-wirell is foraminous and'there fore permeable'to both. water and-aim; Thfi lillllalz'lfifiCh 21a of'the -belt 21- forms a .bottom for=the foraminnus wire 11, and as this bottom is-pulled away. from the? wire along the-downwardly inclined reach or run 72th..- a constantly increasing gap twill-be created bet eem-the: wire and belt. This creates-a suction pump effect. and a reduced o essurerarea Adirec-tly -.underlving the wire: is formed; This reduced pressure,Uinnconjunction.withu atmospheric pressure exerted on the upper surface of the wire, will serve to force drainage of water from the wire.

The drained white water deposited on the belt will either run down the inclined belt surface presented by the reach 21b or will be flung tangentially from the belt' 21 as it passes down the guide roll 24 by centrifugal force. The direction lines B of Figure 1 illustrate this flinging of water from the roll 24 and from the belt 21 and it will be seen that an arcuate deflector 26 having an upper scraper blade 27 underlying or contacting the wire 11.is provided to prevent the flinging of water against the under surface of the Wire. Water from the deflector 26 and from the belt 21 may be conveyed by gravity or other means to a conventional save-all pan.

An additional deflector 28, having an upper scraper blade 29 contacting the wire 11 or spaced very closely therefrom, is provided in advance of the belt 21 and the first guide roll 22. The scraper blade 29 serves to remove excess water from the under surface of the wire 11 prior to its contacting the belt reach 21a, thereby preventing possible interference of this excess water with operation of the water removal device 20.

It will be appreciated that the belt 21 contacts the undersurface of the wire 11 and is driven by the wire 11 and the drive mechanism for the wire. In Figure 2, there is illustrated a modified form of the present invention indicated generally by reference numeral 30. The device 30 is quite similar to the device 20 hereinbefore described and in the two figures identical reference numerals refer to identical portions of the apparatus. In this embodiment of the invention, an auxiliary source of energy, such as an electric motor 31, is provided to drive the belt 210 by suitable means, as by an endless drive belt 32 trained about a pulley 33 on the roll 24 and the shaft of the motor 31. In this manner, it is not necessary to rely upon the frictional engagement of the belt reach 21a with the belt 11 for driving the belt. However, it is preferred that the belt 21 be driven substantially the same speed as the wire 11.

In addition, a pair of transversely spaced side closure plates 35 is provided to extend along the longitudinal edges of the belt 21 (Figure 4). It will be seen that the end plates 35 serve to prevent the drawing of air into the longitudinal extremities of the space A defined between the belt reach 21!; and the wire 11. Thus the suction effect is increased by the provision of such side plates, although they may not be necessary on a large machine inasmuch as the spacing between the belt reach 21b and the wire 11 is very small when compared with the transverse width of the wire and the belt. Each side plate bridges the gap between the belt 21 and the wire edges and the plates extend along the length of the entire free reaches 21a and 21b of the belt.

The operation of the device of the present invention has been described in some detail, and it will be evident to those skilled in the art that the present invention provides means for aiding in the removal of excess water from paper web while supported on a forming wire. It will be appreciated that various details of the structure and operational conditions may be varied as desired as indicated by the dictates of the specific apparatus and the mode of operation of the particular machine.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

1. In combination with a Fourdrinier-type paper machine forming wire, an impermeable belt disposed beneath said wire, spaced guide rolls maintaining a reach of said belt in contact with the undersurface of said wire, and an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire. thereby defining a reduced pressure area directly underlying said wire and said last-mentioned guide roll serving upon rotation to fling water from said belt by a centrifugal action.

2. In a Fourdrinier-type paper machine, a looped foraminous forming wire having a substantially horizontal forming reach presenting an upper and an undersurface, means for introducing a paper stock suspension onto the upper surface of said wire, an impermeable belt disposed beneath said Wire, spaced guide rolls maintaining a first reach of said belt in contact with the undersurface of said wire, and an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire, thereby defining a reduced pressure area directly underlying said wire, and said last mentioned guide roll serving upon rotation to fling water from said belt by centrifugal action.

3. In combination with a Fourdrinier-type paper machine forming wire, an impermeable belt disposed beneath said wire, spaced guide rolls maintaining a first reach of said belt in contact with the undersurface of said wire, an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire, thereby defining a reduced pressure area directly underlying said wire, said last mentioned guide roll serving upon rotation to fling water from said belt by centrifugal action, and an arcuate deflector underlying said wire and in spaced relation to said belt along the travel of the wire for receiving water thrown from said belt.

4. In a Fourdrinier-type paper machine, a looped foraminous forming wire having a substantially horizontal forming reach presenting an upper and an undersurface, table rolls supporting an initial run of said horizontal reach, suction boxes underlying a later run of said horizontal reach, means for introducing a paper stock suspension onto the upper surface of said wire at said initial run, and a liquid removal device positioned within the loop of the wire between the table rolls and suction boxes, said device comprising, in combination, an impermeable belt disposed beneath said wire, spaced guide rolls maintaining a first reach of said belt in contact with the undersurface of said wire, and an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire, thereby defining a reduced pressure area directly underlying said wire, and said last mentioned guide roll serving upon rotation to fling water from said belt by centrifugal action.

5. In combination with a Fourdrinier-type paper machine forming wire, an impermeable belt disposed beneath said wire, spaced guide rolls maintaining a first reach of said belt in contact with the undersurface of said wire, an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire, thereby defining a reduced pressure area directly underlying said wire, and said last mentioned guide roll serving upon rotation to fling water from said belt by centrifugal action, and side closure plates extending along the first and additional belt reaches in close-running relation to the lateral edges thereof to cooperate in defining the reduced pressure area.

6. In combination with a Fourdrinier-type paper machine forming wire, an impermeable belt disposed beneath said wire, spaced guide rolls maintaining a first reach of said belt in contact with the undersurface of said wire, an additional guide roll guiding said belt from contact with said undersurface along the direction of travel of the wire to provide an additional belt reach lying at an acute angle with respect to said wire, thereby defining a reduced pressure area directly underlying said wire, said last mentioned guide roll serving upon rotation to fling water from said belt by centrifugal action, side closure plates extending along the first and additional belt reaches in close-running. relation to the lateral edges thereof to cooperate in defining the reduced pressure area, and an arcuate deflector underlying said wire and in spaced relation to said belt along the travel of the wire for receiving water thrown from said belt.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,577,897 Danninger Mar. 23, 1926 1,984,484 Kilberry Dec. 18, 1934 FOREIGN PATENTS Number Country Date 13,262 Great Britain June 22, 1908 298,671 Great Britain Oct. 15, 1928 378,100 Great Britain Aug. 11, 1932 577,195 Germany May 11, 1933

Images