US2440727A - Papermaking apparatus - Google Patents

Description

May 4, 1948 J. A. ROSMAIT PAPER MAKING APPARATUS Filed Feb. 14,1945.

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" Patented May 4, 1948 PAPERMAKING APPARATUS John A. Rosinait, Appleton, Win, assignmto D. J. Murray Manufacturing 00., Wausau, Wia, a corporation of Wisconsin Application February 14, 1945, Serial No. 577,864

8 Claims. 1

The present invention relates generally to improvements in the art of manufacturing paper from fibrous pulp, and relates more specifically to improvements in the construction and operation of apparatus for distributing and mixing the pulp stock and for controlling the flow thereof through and from the head box of a Fourdrinier type of paper making machine.

The primary object of my invention is to provide various improvements in the construction and operation of fibrous pulp mixing and feedin equipment for use in the head boxes of paper making apparatus, whereby therapid production of better paper is made possible.

It has heretofore been customary in the manufacture of paper with the aid of ,Fourdrinier types of paper making machines, to provide so- .called distributor or rectifying rolls in the head boxes of such machines, these prior rolls usually comprising rotating perforated cylinders disposed both in the final pass and at the delivery end near the slice inlet of each head box. While it able fibre accumulation, besides preventing them from effectively mixing and distributing the pulp during normal use. In order to insure most effective mixing and uniform distribution of the fibres prior to delivery of the pulp to the slice inlet ofthe Fourdrinier wire, the distributing devices whether of the drum or vaned type, must be smooth and devoid of fibre collecting corners and projections throughout, since any pits of irregularities to which fibres may cling temporarily and from which compact masses .of fibre may subsequently be periodically released, will obviously result in non-uniformity and malformation of the sheets and possiblesubse'quent disruption or breakage thereof. Then too, in order to prevent objectionable deflection of the distributing de-" vices for machines having relatively wide head boxes and Fourdrinier wires, it is necessary to construct the prior rolls of heavy metal thus making them cumbersome to handle during insertion and removal while effecting wash-ups and cleaning of the paper making installations; but in spite of these various objections the operators have continued the use of this antiquated equipment for many years.

It is therefore a more specific object of my present invention to provide improvements in flow mixing and distributing devices for the feed or head boxes of such paper making machines, which will substantially eliminate all of the objectionable features of prior equipment of this kind and will thereby facilitate the production of superior paper at higher speeds than are possible with the prior mechanisms.

Another specific object of this invention is to provide an improved system of mixing rotors adapted for use in successive flow passages through the head box of a Fourdrinier machine, whereby most efiicient homogeneous mixing and distribution of the fibres throughout the entire area of the stream of stock as it approaches the slice inlet, is definitely assured at all. times regardless of the speed at which the machine is being operated.

A further specific object of the invention is to provide an improved mixing rotor assemblage and journal support therefor, whereby the rotor it may be quickly and conveniently installed or removed for inspection or cleaning, while also,

being devoid of objectionable deflection during normal operation. j

Still another specific object of the present invention is to provide an improved flow mixer which is simple and durable in construction, which may be formed of relatively inexpensive smooth surfaced material in a manner which will positively eliminate objectionable local 80-. cumulation of fibre masses, and which is built to insure most effective mixing of pulp during normal use.

An additional specific object of my invention.

- may be easily repaired at moderate cost in case a-section thereof should be accidentally damaged.

Another additional specific object of this in vention is to provide various new and useful improvements in pulp mixing rotors for paper thereof;

making machines, whereby the construction, manipulation, and operation thereof is facilitated, while the efficiency is augmented to the maximum and the maintenance cost is reduced to a minimum.

These and other specific objects and advantages of the invention will be apparent from the following detailed description.

A clear conception of the various features constituting my present improvement, and of the construction and operation of numerous types of mixing rotors built in accordance with the invention, may be had by referring to the drawings accompanying and forming a part of this specification wherein like reference characters designate the same or similar parts in the various views.

Fig. 1 is a somewhat diagrammatic vertical section taken longitudinally through the surge tank, flow spreader, head box, and a fragment of the Fourdrinier wire of a paper making machine, showing a transverse section through the improved flow mixers associated with the head box;

Fig. 2 is a transverse section through the head box of the assemblage shown in Fig. 1, taken along the line 2-2 and looking toward the mixing rotors;

Fig. 3 is a fragmentary greatly enlarged central longitudinal section through the driving end.

and one of the removable bearings of a typical embodiment of my improved mixing rotor, also showing a fragment of the adjacent head box wall in section;

Fig. 4 is a somewhat reduced part sectional elevation of the opposite end portion of the threepiece four blade mixing rotor assemblage shown in Fig. 3;

Fig. 5 is a transverse vertical section through the mixing rotor of Fig. 4, taken along the line 5-5;

Fig. 6 is another transverse vertical section through the same rotor; taken along the line 6-6 of Fig. 4; I

Fig. '7 is still another transverse vertical section through the same mixing rotor, taken along the line 'l'| of Fig. 4;

Fig. 8 is a somewhat enlarged end view of a one-piece four vane mixing rotor embodying the invention, and adapted to cooperate with removable end bearings such as shown in Fig. 3;

Fig. 9 is a transverse vertical section through the one-piece rotor of Fig. 8 taken medially Fig. 10 is a similarly enlarged end view of an eight vane seven-piece mixing rotor also embodying the invention, and especially-adapted for cooperation with removable journal bearings such as shown in Fig. 3 and for use adjacent to the final outlet of the head box;

Fig. 11 is a transverse vertical section taken medially of the ends thereof, through another eight vane mixing rotor adapted for use adjacent to the slice inlet, and formed of seven pieces;

Fig. 12 is a smaller elevation of a fragment of the main spanning piece of the rotor of Fig. 11, showing an end thereof applied to one of the end. supporting shafts;

Fig. 13 is a fragmentary elevation of one end portion of another type of four vane mixing rotor embodying the invention, and comprising a number of end coacting vane sections and intervening connecting members;

Fig. 14'is a transverse vertical section through the mixing rotor of Fig. 13 taken between two successive vane connecting members;

Fig. 15 is an end view or one of the vane connecting members of the rotor shownin Figs. 13 and 14 showing the central tension bolt in section:

Fig. 16 is another fragmentary elevation of one end portion of still another four vane type of the improved mixing rotor, comprising a number of overlapping and directly united end coacting sections;

Fig. 17 is a transverse vertical section through a mid-section of the rotor of Fig. 16, taken intermediate the ends of the section;

Fig. 18 is still another fragmentary elevation of an end portion of a further modified four vane sectional flow mixing rotor, the sections of which have transverse cross-sections similar to that of Fig. 17;

Fig. 19 is an elevation of the major portion of I a four vane rotor having the vanes thereof twisted in opposite directions proceeding from the opposite ends thereof toward the center; and Fig. 20 is another elevation of the major portion of still another four vane twisted rotor having the vanes thereof twisted helically in the same direction from one end of the rotor to the other.

Although the present disclosure has been confined to four and eight vane mixing rotors provided with special axially removable end shafts and bearings and formed primarily of light material such as plastic, it is not my desire or intention to unnecessarily limit the invention or to restrict its utility by virtue of the embodiment of all or several of these features in a single assemblage.

Referring especially to Figs. 1 to 7 inclusiveof the drawing, the paper making machine illustrated therein comprises in general a surge tank 2| normally communicating with the pulp screens of a paper making installation and having a lowerdi'scharge opening which communicates with a flow spreader 22; a Fourdrinier wire 23 of any suitable width coacting with a breast roll 24 and being provided with a slice inlet 25; a head box 26 interposed between the discharge end of the spreader 22 and the slice inlet 25 and having therein several transverse partitions 21 coacting with side walls 28 to form successive oppositely directed passes for the pulp 29 normally flowing through the box; a four vane relatively large diameter mixing rotor 30 spanning and being rotatable within the final pass 3| of the head box 26; and an eight vane mixing rotor 32 of smaller diameter spanning and being rotatable in the outlet end of the head box 26 directly adjacent to the slice inlet 25.

While some of this apparatus is of rather well known construction, it is noteworthy that in the assemblage shown in Figs. 1 and 2, the initial mixing rotor 30 which is located in the vertical portion of the final pass 3| of the head box 26 is provided with only four vanes and is of considerably larger diameter than the eight vane final mixing rotor 32 which is disposed near the slice inlet 25 of the Fourdrinier wire 23, and this difference between the rotors 30,

32 is an important feature of my present invention for reasons which will hereafter be set forth more in detail. The ,opposite side walls of the head box 26, are ordinarily provided with suit- 4 pended from the sidewalls 28 of the head box' '28 by means of alined end shafts 34, 35 and special bearing assemblages 36 associated with these shafts. The shafts 34 which project outwardly beyond the adjacent bearing assemblages 36, are the driving shaftsand may be provided with suitable drivingsheaves or sprockets 31 as indicated in Fig. 2, and these driving sprockets 31 may be keyed or otherwise detachably connected to the protruding shaft ends.

The improved shaft and bearing assemblage 36 associated with each end of each mixing rotor 36, 32, is shown in detail in Fig. 3, andcomprises a bearing housing 38 having an integral tubular end 39 snugly fitting a bore in the adjacent wall 28 and being firmly but detachably secured to this wall by means of cap screws 40; a rotor supporting shaft 34 or 35 disposed concentric with the bores of the housing 38 and having a polygonal end portion 4| slip fitted within the adjacent similarly polygonal end socket 42 of the rotor 30, each supporting shaft also being provided with a cylindrical bearing portion 43 and with ,an integral circular flange 44 disposed between the portions 41, 43 thereof; a self-lubricating guide bearing 45 formed of graphite or the like, and coacting with the cylindrical portion43 adjacent to the flange 44, this bearing 45 being snugly fittedwithin the smallest bore of the housing 38; a self-aligning ball hearing 46 interposed between the supporting shaft and the housing 38 outwardly beyond the cylindrical shaft portion 43 and being held in place by a nut 41 and an outer cap 48; a pair of sealing rings 49, 58 coacting with the shaft portion 43 i between the bearings 45, 46 and being spaced apart by a spacing sleeve and leakage drainage passages 52 formed in the housing 38 and sleeve 5i forconducting liquid which escapes past the bearing 45 from the assemblage.

In the bearing assemblages 36 which coact with the outwardly protruding driving shafts 34, the end cap 48 is provided with an additional packing ring 53, but these rings 53may be omitted from the end caps 48 coacting with the opposite end shafts which may be closed to conceal these shafts; and in both cases the caps 48 are detachably secured to the adjacent housings 38 by cap screws 54. .By providing such a bearing assemblage 36 at each end of each rotor 36, 32, these rotors may be quickly and conveniently released from their supporting shafts 34, 35 by merely removing the cap screws and by thereafter sliding the released assemblages axially away from the intervening rotors until the polygonal shaft portions 4! have been completely withdrawn from the adjacent rotorsockets 42. The released rotors 36, 32 may then be lifted freely from within the head box 26, and reassembly of the rotors and their supporting assemblages 36 may obviously be just as quickly and conveniently effected.

The rotors 36, 32 which are preferably formed of light but durable material having smooth surface finish, such as plastic, may be constructed in various ways in accordance with my present improvement, and in the improved typical rotor structure specifically illustrated in Figs. '3 to 6 inclusive, the four vane rotor assemblage comprises three pieces, namely, a fiat main flight or vane 55 formed integral with both end sockets 42, and a pair of aligned auxiliary flights or vanes 56 disposed perpendicular to the main vane 55 and being firmly secured thereto by means of several rod rivets 51, all of the vanes 55, 58 extendingthroughout the full'lengthof the rotor 30. The main vane 65 is centrally rigid but is preferably provided with a series of holes 58 ofrelatively large diameter spaced uniformly throughout the wing portions thereof,

while the auxiliary vanes 56 are. cut away at I the center of the rotor and are pierced by series 6 of uniformly spaced smaller holes 53; and these holes 58, 58as well as all other portions of the rotor assemblage, are provided with rounded corners andare devoid of fibre collecting pockets and projections. The auxiliary vanes are also thickened at the points of penetration. thereof by the rivets 51, in order to avoid weakening of the vanes; and the end portions of these vanes 56 are also slip fitted into parallel grooves 60 formed in the end sockets 42, so as to enhance the rigidity of the rotor 30.

"With large and small openings or holes 58, 5,9

uniformly spaced throughout the areas thereof. The square or otherwise polygonal socket. 42 of this modified one-piece four vane rotor 36 are cooperable with the similarly polygonal inner end portions of supporting shafts 34, 35 in the manner previously described, andthis unitary type of rotor assemblage should likewise -be devoid of fibre collecting projections and corners and should have smooth surface finish throughout. The unitary construction of the rotor 30 of Figs. 8 and 9 obviously provides a strong assemblage in which there are'no parts which could possibly become loose and dislodged from the others.

The smaller eight vane rotors 32 may also be, built in various ways, eitherwithout a cross member formed integral with the opposite end sockets 42, or with an integral cross-connection. as shown in Figs. 10, 11 and 12. In the embodiment of Fig. 10, the spaced end sockets 42 of the eight vane rotor 32, are provided with alined series of parallel recesses 62, and the radial vanes 63 have their ends snugly fitted within these recesses 62 and rigidly secured to the sockets 42 in any suitable manner. The successive vanes 53 are provided with large and small openings 58, 59 respectively, spaced throughout the areas thereof,- and this rotor 32 should also be devoid of sharp edges upon which fibres arelikely to accumulate. As specifically shown in Figs.'11 and 12, the oppositeend sockets 32 are formed integral with a main flight or vane 64 having large openings 58 therein, and being provided with bosses 65 having openings therethrough disposed at 45 angles and perpendicular to the plane of the main vane.64; and auxiliary inclined and perpendicular vanes 66, 61 are secured to the main vane 64 at the local bosses 55 by means of rod rivets 51 passing through the boss openings. The perpendicular vanes 6'! should also be provided with large openings 58, while the inclined vanes 66 shouldbe provided with smaller openings 58 throughout their areas; and the opposite ends of the auxiliary vanes 66, 61 .may .be snugly fitted within parallelalined recesses 62 in the end sockets 42 as in Fig. 10.

The rotors 30, 32 if of great length, may also nected sections as illustrated in Figs. 13 to 18 inclusive. In the embodiment of' Figs. 13, 14 and 15, the rotor 88 comprises a series of aligned fourvane sections 68, 89 each having four integrally united vanes radiating from a common axis; and a series of cross-shaped connecting members 18 having cross-grooves H for snugly receiving the ends of the sections 68, 69. The end sections 68 are formed integral with the end sockets 42 which are cooperable with the polygonal portions 4! of the adjacent shafts 84, 85, and all of the sections 88, 69 may be joined by a central tension bolt 12 extending axially through the rotor.

holes 58, 59 as shown; and alledges of the sections 68, 88 and of the cross-members I8 should preferably be rounded, while the surfaces there- The vanes of the successive sections 88, 69 are preferably provided with large and small of should be as smooth as possible. Any desired 7 otherwise uni-tedto provide a rigidrotor struc-.

ture.

In the embodiment of Figs. 16 and 17, the rotor 38 comprises a series of alined four-vane sections 13, 14 each of which also has .fpur integrally united perforated vanes radiating from the rotor axis; these sections having overlapping adjacent ends I5 firmly united by rivets 18; The end sections 13 are formed integral with the supporting vane 82 by transverse rod rivets 51 and again having their end portions snugly fitted within parallel recesses 88 formed in the end sockets 42.

The vanes 88, 8|, 82, 88 of these twisted vane rotors are again provided with holes 88, 58 preferably covering the major areas thereof, and should likewise be devoid of sharp pockets and cornersupon which fibres might accumulate.

When constructing an installationln accordance with my present invention, it is preferable to provide a rotor 88 of relatively large diameter and having relatively few vanes, in the final pass 8| of the head box 26, and to also provide a rotor 32 of relatively smaller diameter but having a greater number of vanes near the slice inlet 25. The reason for providing such diflerent rotors 88, 82 at the two locations, is so that the pulp will be rather gently agitated and thoroughly mixed in the larger upwardly directed conduit of the final pass 3|, and will be more rapidly agitated and thoroughly mixed as it leaves the slice inlet leading to the Fourdrinier wire 23. During nor-' mal operation of the paper making machine the rotors 88, 82 should be constantly rotated in the direction indicated by the arrows in Fig. 1, by

application of driving power tothe sprockets 81 shown in Fig. 2, and the pulp flowing through the head box 28 will obviously be constantly and thor- V erably be arranged as shown inthe various rotors,

end sockets 42, and a tension bolt 12 also extends centrally through and additionally unites the sections 18, 1 4 to form a sturdy ro tor 88. In the specific embodiment of Fig. 18, the rotor 88 also comprises aiseries of alined four vane sections 18 each having four integral perforated vanes radiating from the central rotor axis; but alterof similar sections may be utlized in either the four or eight vane type of rotor 88. 82, in an obvious manner.

More efiective distribution of the pulp being acted upon by the mixing rotors 88, 82 may also be obtainable by providing twisted or helical vanes as specifically shown in Figs. 19 and 20.

'In the embodiment of Fig. 18, I have shown a four vane rotor 88 having four radiating vanes twisted in opposite directions from the end sockets 42 toward the center. main twisted vane 88 integrally united with the opposite end supporting sockets 42, and a pair of auxiliary twisted vanes 8| secured to the opposite sides of the main vane 88 by transverse rod rivets 51 and having their inner end portions fitted within parallel recesses 88 formed in the end sockets 42. In Fig. 20, I have shown a four vane rotor 88 having four radiating vanes twisted helically in the same direction throughout their entire lengths, and this rotor comprises a main twisted vane 82 formed integral with the opposite end sockets 42, and a pair of auxiliary twisted vanes 88 secured to the opposite sides of the main The ends of the coacting sections II, 18

This rotor 88 comprises a that is, with successive vanes having perforations of difierent sizes therein, in order to additionally enhance the agitating and mixing action of the rotors without undesirably obstructing the flow past these rotors. will ordinarily effectively perform their functions, it may be desirable to cause the pulp to flow back and forth with respect to the side walls 88 of the head box 26. as it passes these rotors.

and this action can be gently produced by providing twisted vane rotors such as shown in Figs. 19 and 20. In relatively narrow head boxes 28 it may be preferable to utilize one-piece rotors such' as shown in Figs. 8 and 9, but in the case of longer rotors, the construction thereof may be facilitated either by providingemain and auxililiary vanes as in Figs. 4, 5, 6, 10,11 12, 19 and 20, or by providing sectional rotors such as shown in Figs. 13 to 18 inclusive. In all cases, the rotor assemblages 88, 82 are made readily insertable and removable by utilizing detachable bearing assemblages 88,. such as shown in detail in Fig. 3, and the rotors 88, 82 should also preferably be formed of relatively light material such as plastic and should have smooth. surfaces throughout and be devoid of sharp corners and projections which might tend to cause the fibres to cling thereto.

From the foregoing detailed description it will be apparent that my present invention provides an improved iiow mixing and distributing systern for the head boxes of paper making machines, whereby continuous and uniform treatment of the pulpflis assured at all times, and wherein the vari- I one passages and parts are readily accessible for inspection and cleaning. The use of successive 'rotors 88, 82 of diflerent diameters having a different number of mixing vanes or paddles and perforations of different sizes, enhances the mixing effect and insures uniform distribution of the fibres throughout'the entire width of the slice While the straight vane rotors l for slight deflections whilestill maintaining the end shafts and the intervening rotors in proper alinement at all times.

In accordance with the invention, the rotors 30, 32 may obviously be formed in one piece, of several readily united parts, of end unitable sections of any desired length, or of twisted vane construction, in order to most eifectively meet various operating conditions. While the onepiece structure positively eliminates loose parts;

the three-piece four vane rotors of Figs, 4, l9 and 20, and the seven-piece eight vane rotor of Figs. 11 and 12 may be readily manufactured and. firmly assembled to produce strong and durable structures. The sectional rotor structures of Figs. 13 to 18 inclusive may be advantageously utilized to produce rotors of variouslengths from stock sections; While the twisted vane rotors of Figs. .19 and 20 have the advantage of working the pulp stream laterally so as to insure perfect distribution of the fibres throughout the entire flow area. The smooth formation of these rotors 30, 32 with rounded corners and devoid of pockets, is important in order to eliminate local fibre accumulations, and the use of perforations 58, 59 of diiferent sizes properly applied to the successive vanes is also important in order to enhance the effectiveness of fibre distribution throughout the pulp stream. It is also noteworthy that in the improved assemblage, the removable rotors are locatedin the head box 26 out of vertical alinement with each other, so that each of these rotors may be freely independently removed without bers, said vane-radiating from the common axis of said sockets and being helically twisted in opposite directions about said axis proceeding from said sockets toward the medial vane position.

3. A flow mixer for a paper making machine, comprising, a pair of. end members having co.- axial sockets each having a supporting shaft coacting therewith, each of said members also having external grooves therein and extending longitudinally thereof on opposite sides of its socket, a longitudinally twisted vane flrmlyuniting said members between said grooves, and other longitudinally twisted vanes slip fitted within said member grooves and coacting with the opposite sides of said first mentioned twisted vane.

4. A flow mixer for a paper making machine, comprising, a pair of end members having coaxial sockets each having a supporting shaft coacting therewith, each of said members also having external grooves therein and extending longitudinally thereof on opposite sides of its socket, a longitudinally twisted vane firmly unit-V ing said members between said grooves, and other longitudinally twisted vanes slip fitted within said member grooves and coacting with the opposite sides of said first mentioned twisted vane. all of said vanes radiating from the common axis of said sockets and being helically twisted in opposite directions about said axis proceeding from said sockets toward the medial vane portions.

5;"A flow mixer for a paper making machine, comprising, a pair of members provided with coaxial polygonal-sockets each having the similarly polygonal end of a supporting shaft slip fitted therein, each of said members also having external grooves therein on opposite sides of its socket, a main vane rigidly uniting said members between said grooves and extending across the common axis of said sockets, and auxiliary vanes slip fitted within said grooves and being secured to the opposite sides of said 'main vane, all of said vanes radiating from said axis.

disturbing the other. The improved rotors 30, 1

art.

I claim:

1. A flow mixer fora paper making machine, comprising, a pair of members provided with pended claims, may occur to persons skilled in the axially alined sockets each having a supporting shaft coacting therewith, and a plurality of longitudinally twisted perforated vanes interposed between and secured to said members, said vanes radiating from a common axis and being uniformly helically twisted in opposite directions relative to said axis and proceeding from said sockets toward the medial vane portions. 2. A flow mixer for a paper making machine,

comprising, a pair of members having coaxial sockets each having a supporting shaft coacting therewith, and a longitudinally twisted vane interposed betweenand interconnecting said mem- 6. A flow mixer for a paper making machine,

comprising, a pair of spaced members provided with coaxial sockets and each having external longitudinal grooves on opposite sides of its socket, a supporting shaft coacting with each of said sockets and being removable axially therefrom, a main va'ne rigidly uniting spanning the space between said members and extending across the common axis of said sockets, and auxiliary vanes having end portions fitted within said grooves and being secured to the opposite sides of said main vane.

7. A flow mixer for a paper making machine,

comprising, a pair of spaced members Provided with coaxial sockets and each having external longitudinal grooves on opposite sides of its socket, a supporting shaft coacting with each of said sockets and being removable axially therefrom, a main vane rigidly uniting and spanning the space between said members and extending across the common axis of said sockets, auxiliary vanes having end portions slip fitted within said grooves and spanning said space on the opposite sides of said main vane, and means for firmly connecting the medial portions of said auxiliary vanes to adjacent local portions of said main vane.

8. A flow mixer for a paper making machine, comprising, a pair of spaced members having coaxial polygonal sockets and each'being provided with diametrically opposite external grooves, a

pair of coaxial supporting shafts each having a polygonal end slip fitted'into one of said sockets I and being axially removable therefrom, a main vane integrally uniting and spanning the space between said members and extending across the common axis of said sockets between said grooves, and auxiliary vanes having end portions slip fitted within said grooves and also having medial portions secured to the adjacent opposite side portions of said main vane.

.JOHN A. ROSMAIT.

, REFERENCES CITED The following references are oi record in the tile 0! thispatent:

Number Number 12 UNITED, STATES PATENTS Name Date Murch Oct. 12, 1880 Fieek Aug. 24, 1926 Aldrich -May 17, 1927 Valentine May 1, 1928 Berry Sept. 10, 1929 Ruttiman Dec. 30, 1938 1 Berry June 4, 1940 Ockrant et a1 June 13, 1944 FOREIGN PATENTS Country 7 Date Austria Jan. 10, 1935

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