USRE25333E

USRE25333E - Baxter

Info

Publication number: USRE25333E
Authority: US
Publication date: 1963-02-19

Description

Feb. 19, 1963 BAXTER, JR Re. 25,333

PAPER MACHINERY Original Filed Oct. 13, 1958 4 Sheets-Sheet 1 FIG-'I 175 75 I I6L/ 20 I85 JOSEPH BKX$FE? JR.

BY wwwva AITORNEYS Feb. 19, 1963 J. BAXTER, JR

PAPER MACHINERY 4 Sheets-Sheet 2 Original Filed Oct. 13, 195B 7 9 9 l R M W, 9 9 5 9 m 7 0 J s 5 |v 5 w v 6 m ,7 2 6 6 6 TE 6 \l I 7u :1: .1}: n VA 6 NB .l x 8 I 8 7 6 v u PH L t I i 6 U u 1.1 nlnvflllif 1| mm IV I \I I II II E I o o I III ||l| I n l\ LT l 1/|l L v 9 J W L-l u L I J 8 F W 1 a w 2 I I Y 4 8 B h m. m 7 I W .5 i a f 0 n T ew w 4/1 .8 "n I O n* 8 In T FIG-3 ATTORNEYS Feb. 19, 1963 J. BAXTER, JR

PAPER MACHINERY 4 Sheets-Sheet 3 Original Filed 001;. 15, 1958 FIG-5 INVENTOR. JOSEPH BAXTER,JR.

ATTORNEYS 4 Sheets-Sheet 4 J. BAXTER, JR

PAPER MACHINERY Feb. 19, 1963 Original Filed 001:. 13, 1958 FIG-9 IN VENTOR. JOSEPH. BAXTER, JR.

' Mlg ATTORNEYS United States Patent Ofiice Rs. 25,333 Reissued Feb. 19, 1953 25,333 PAPER" MACHlNERY- Joseph Baxter, Jru, Franklin, Ohio, assignorto TheBlack- M 01 Cr mean) H m t io t w t a i nvf Ohio Original No. 2,969,114, dated Jan. 24, 1961, Ser. No. 767,008; Oct. 13, 1958. Appiicationfor reissue. Feb. 23', 1962, Ser. No. 175,380

29, (Ilaims. (Cl. 162F348).

Matter enclosed in heavy brackets E 1 appears in the original patent but forms no partof this reissue specification; matter. printed in italics indicatcsthe. additions made by reissue.

This invention relates to paper making machines.

The invention in general relates topaper making machines of the type in which a traveling forming web is employed in the formation of a paper sheet, but it offers substantial advantages instructure, mode of operation and results over existing Fourdrinier machines. The primary objective of the invention, however may be more broadly stated as being to provide a paper machine which is capable of producing a continuous sheet of paper of practically matching physical characteristics on both sides thereof, which will produce such a paper sheet wherein the long and short fibers are distributed in such manner as to assure high speeds of operation when the sheet is subsequently used on a printing press While requiring minimum amounts of surface coating consistent with the desired quality of printing, and which is itself capable of operation at desired high production speeds.

A particular object of the invention is to provide a paper machine which will operate as outlined above to produce a paper sheet- Whercin the several constituent materials are distributed within the sheet in desired strata relative to the surfaces of the sheet, and specifically to produce a paper sheet having maximum concentration of long fibers in a central layer of the sheetand maximum concentration of filler materials and other small particles along both surfaces of the sheet for desired smoothness and freedom from two-sidedness,

A further object of the invention is to provide a paper machine of such structure and mode of operation that substantially no air passes through the sheet while it is being formed, thereby reducing the tendency for the formation of craters in the surface of the sheet, and consequently the amount of supplementary coating required to produce a smooth surface, as well as affording economies of construction and operation by reason of the reduction in the requirement for vacuum pumps or like equipment.

An additional object is to provide a paper machine which substantially eliminates the entrainment of air with the stock in the forming zone, and which therefore correspondingly eliminates defects such as pin holes in the sheet caused on conventional paper machines by the escape of entrained air from within the sheet after the sheet has begun to form.

Still another object of the invention is to provide a paper machine which does not require any table rolls such as are used on conventional Fourdrinier machines to support the forming who after it leaves the initial forming zone, and which therefore in operation is free of the undesirable effects of such table rolls in tending to pump water upwardly into the lower surface of the sheet on the upwardly moving side of the roll followed by immediate withdrawal on the downwardly turning side of the roll with the resulting tendency to wash the fine suspensoids out of the sheet.

It is also an object of the invention to provide a paper machine of such structure and mode of operation that 2. the stock can be screened substantially immediately ahead ofits deliv'ery to the forming zone with no time lag or velocity change permitting flocculation to take place.

A further object of the invention is to provide a paper machine wherein the initial orifice of the forming zone may be precisely ground and does not require individual adjustments across; the width of the machinej'to'correct erratic currents, and particularly to provide such a paper machine wherein the initial torjming orifice is defined by a pair of moving walls in such manner that the eitects of skin friction present with the conventional machines are practically non-existent.

Another important object of the invention is to achieve some or all of the above results while at thesame'time providing a paper machine which requires greatly reduced floor space in comparison with existing machines ofconventional construction without sacrificing quality, speed of'operation, or convenience of maintenance.

In accordance with the invention, all these and many other objects andadvantages can be'achieved by the provision of a paper machine of novel structure and operating characteristics wherein the paper sheet is formed while traveling vertically between a pair of foraminous forming webs under such conditions that controlled drainage of liquid takes place simultaneously from both surfaces of the sheet at substantially the same rates. Thus in a preferred embodiment of the invention, the two forming webs travel downwardly through a forming nip defined by a pair of breast rolls mounted in spaced relation in a common horizontal plane, and the stock is delivered directly downwardly into this nip from a headbox of specialconstruction which provides effective screening of the stock just ahead of its delivery to the forming nip. A plurality of pairs of suction rolls are arranged in'vertically spaced relation below these breast rolls to support the forming webs over the remainder of the distances through which they travel while the sheet is being formed, and'thesepairs of rolls are progressively more closely spaced to' cause the stock to be comparted between the forming webs. Special provision is also made by the invention for effecting controlled drainage ofliquid through the successive pairs of suction rolls, and the sheet is conducted away after it reaches the nip of the lowermost pair of suction rolls, which thus also function as couch rolls.

It is an object of the invention to provide a paper machine having the general structural arrangement and mode of operation outlined in the preceding paragraph and which is especially characterized also by its minimum requirements of space in comparison with the length of the forming webs and the speed of the machine.

An additional object of the invention is to provide a paper machine as outlined'above wherein the sheet while it is being formed passes between successive pairs of suction zones which efiect the opposite sides, of the sheet simultaneously and which are subject to individual control such that the degree of suction and the Con responding drainage from the sheet may very in accordance with its desired final characteristics. Thus such control can be achieved in a paper machine of the specific structural arrangement outlined above byindividual control of the suction and drainage through each successive horizontally arranged pair of suction rolls.

further object of the invention is to provide a paper machine of the general structural arrangement outlined above wherein the several breast rolls and suction rolls for supporting the forming webs are mounted in frames which include upright columns at each end of the rolls, and wherein one of these columns for each vertical set of rolls is mounted for rotational movement on a vertical axis to support the other column and associated rolls in cantilevered position for changing the forming webs.

An additional object of the invention is to provide a paper machine as outlined above wherein each of the several suction rolls is mounted in the machine by a pair of end castings which constitute component parts of the frame columns respectively and cooperate with one or more individual connecting members to form a modular unit such that additional pairs of such units and rolls can be added to the machine for the purpose of lengthening the effective paths of the forming webs, and thereby increasing the speed of operation of the machine, without increasing the floor space required by the machine.

A further object of the invention is to provide a paper machine as outlined above wherein the end castings in one frame column for each vertical set of rolls are connected with the main source of suction for the machine, each casting in the other frame column includes valve means for regulating the suction and drainage through the associated suction roll, and the connecting members between the complementary pairs of castings are hollow for drainage therethrough from one column to the other.

Still another object of the invention is to provide a paper machine having some or all of the features outlined above wherein one or more deflector plates may be mounted above each suction roll in close proximity to the associated forming web for the purpose of deflecting freely flowing liquid onto the surface of the roll ahead of its area of contact with the forming web in such manner that such liquid may be immediately removed to the interior of the roll rather than tending to form a puddle in the nip of the roll with its horizontally associated suction roll on the opposite side of the sheet.

It is a further object of the invention to provide a paper machine offering the features and advantages outlined above wherein the forming zone is effectively sealed from the outside atmosphere, and in fact may be continuously under controlled suction, in such manner as to minimize the possibility of leakage of liquid in the vicinity of the machine.

Many further objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings:

FIG. 1 is a view in vertical section illustrating the general construction and mode of operation of a paper machine in accordance with the invention, the view being taken as indicated by the line 1-1 of FIG. 3;

FIG. 2 is an enlarged fragment of FIG. 1 further illustrating details of the forming zone of the machine;

FIG. 3 is an elevational view of the paper machine of FIG. 1, looking from left to right in FIG. 1 with some parts removed;

FIG. 4 is an enlarged fragmentary section on the line 4-4 of FIG. 3, with parts further broken away;

FIG. 5 is an enlarged fragmentary view in horizontal section taken as indicated by the line 5-5 of FIG. 3;

FIG. 6 is a fragmentary and somewhat diagrammatic view in the nature of a perspective illustrating internal structural details of the machine of FIGS. 1-5, and particularly details of the members for sealing the forming zone;

FIG. 7 is an enlarged fragmentary section on the line 7-7 of FIG. 3;

FIG. 8 is an enlarged fragmentary section on the line 8-8 of FIG. 3 to illustrate the sealing mechanism between side edges of the forming webs;

FIG. 9 is an elevational view looking at the tending side of the paper machine of FIGS. 1-8 and illustrating its operating connections with the first press section such as is used with conventional paper machines; and

FIG. 10 is a somewhat diagrammatic fragmentary elevational view illustrating a suitable drive arrangement and additional details of the paper machine of FIGS. 1-9.

Referring to the drawings, which illustrate a preferred embodiment of the invention, the machine includes two sections which are substantially identical with each other and each of which constitutes approximately one-half of the forming portion of the machine. More specifically, one side of the machine includes a breast roll 20 and three

suction rolls

21, 22 and 23 which are mounted in generally vertically aligned relation below the breast roll 20 and cooperate therewith and with suitable guide rolls 26 and a squaring roll 27 to support a forming web of suitable foraminous structure, such as a conventional forming wire or a woven fabric or felt web. The other side of the machine includes an identical arrangement of breast roll 3%,

suction rolls

31, 32 and 33, forming web 35, guide rolls 36 and squaring roll 37. These two sections of the machine are arranged in relatively closely spaced relation such that their respective breast rolls define a vertically extending nip 33 therebetween, and the two forming webs are thus supported for downward travel through and below this nip.

A single headbox 40 is mounted on top of the machine and includes a pair of depending

lips

41 and 42 defining a downwardly extending discharge passage 44 for delivering stock to the nip 38 of the breast rolls 2t) and 30 for continued downward travel between the forming

webs

25 and 35. The liquid in this stream of stock is progressively withdrawn through the forming webs by means of the successive suction rolls to form a continuous fiber sheet 45, and since the thickness of this sheet is progressively decreased as the liquid is withdrawn, the successive pairs of suction rolls are located in progressively more closely spaced relation to cause corresponding narrowing of the gap between the forming webs.

The lowermost pair of suction rolls 23-33 act as couch rolls, and the sheet 45 which emerges from their nip is conveyed to the next section of the paper machine by a felt 46 and transfer roll 47, which may be conveniently mounted as indicated in FIG. 1 below either of the lowermost suction rolls, shown as the roll 33. The return flights of the two forming webs are shown as cleaned by suitable showers 50 in combination with drip pans 51 to receive the wash water through the forming webs, and similar showers 53 may be employed to effect continuous cleaning of each of the suction rolls. FIG. 1 also shows one of the jet nozzles 54 for trimming the edge of the sheet 45 before the latter reaches the nip of the suction rolls 23 and 33, and the resulting trim strips 55 are readily separated from the sheet 45 by suitable arrangemcnt of conventional deckles (not shown) within the

rolls

23 and 33.

Considering now the general structure of one of the two sections of the machine, and referring particularly to FIG. 3, there is a pair of pedestals and 61 located at opposite sides of the machine, the pedestal 69 being located at the drive side and the pedestal 61 at the tending side, and there is a similar pair of

pedestals

62 and 63 for the other section of the rolls. The several rolls zit-23 are each supported at opposite ends by identical pairs of

castings

65 and 66 stacked on the

pedestals

60 and 61 respectively. A pair of

cross tubes

67 and 68 form a rigid connection between each pair of

castings

65 and 66 to complete this portion of the machine frame, and identical sets of castings 65-66 and cross tubes 67-68 support each of rolls 30-33. Each of the cast ings 65-66 is also shown as incorporating a boss or pad 69 which can serve as a mounting for a bearing for one of the guide or squaring rolls shown in FIG. 1.

Provision is made in accordance with the invention for pivotal movement of each section of rolls on its

pedestal

60 or 62 to support the several rolls and their associated castings 66 in cantilevered position for changing the forming web thereon. Referring to FIG. 3, the pedestal 60 is provided on its upper end with a short cylindrical tube 70 on which the lowermost casting 65 is mounted for pivotal movement, and the upper surface portion 71 of the pedestal 60 accordingly forms a bearing surface for J this casting 65. An inlet tube '72'for lubricant is arranged to supply grease to this bearing surface 71, as by means of a conventional grease gun, to float the cast ings 65 sufficiently for free turning movement.

The other pedestal 61 cooperates with a removable block 74 to support the lowermost casting 66 during normal operation of the machine. In addition, the pedestal 61 incorporates one or more fluid pressure cylinders having pistons 75 which in their normal retracted positions lie out of contact with the lower surface of the adjacent casting 66. When the forming web 25 is to be changed, it is merely necessary to operate these cylinders so that their pistons '75 raise the castings 66 sufficiently for removal of the block 74, after which the pistons 751are again retracted, and the entire section can be swung, sufliciently on the pedestal 69 for removal and replacement of the web 25. The same procedure applies for changing the web 327, in which case the roll section is similarly cantilevered on the pedestal 6-2. Additional support may be provided, particularly during wire changing by a diagonal brace 76- extending from the lowermost casting 66'to the uppermost casting 65 as indicated in FIG. 3.

In additionto supporting the several suction rolls, the castings 65-456 and cross tubes 67-68' also form portions of the system for removing water from the sheet More specifically, the

45 by way of the suction rolls. interior of the pedestal 69 is connected as indicated in FIG. 3 to a suitable source 35] of suction, which for example may be a vacuum pump or a centrifugal pump, and the line 81 from the pedestal so to the source as is shown as connected at 82 to the pedestal 6t) and running through the floor and ultimately to a conveniently located couch pit S5. The extension '76 connects the interior of the pedestal titi with the lowermost casting 65, and all of these castings are largely hollow and open at both top and bottom so that they similarly connect with the pedestal 6% for the free flow of white water thereto.

The castings 65 each incorporate means for eiiecting controlled suction and drainage of white water through the associated suction rolls and for delivernig such white water by way of the cross tubes 6768 to the associated casting 65. This control means, as well as the general construction and mounting arrangement for one of the suction rolls, are shown in detail in FIGS. and 6, and the same structure is indicated as employed for each of the other suction rolls.

Referring to FIG. 5, the heads Wand hi of suction roll 22 are journaled in bearings 92 each mounted on a platform bracket 93 on the inner side of the associated casting 65 or es. As shown in FIG. 6, means are provided, such as slots 95 in each of thebrackets 93 to receive the mounting bolts 96 for the bearings 92, for eiiiecting adjustment of the bearings 92 towards and away from the castings sa es to regulate the reflective width of the nip formed by the roll 22 and its corresponding suction roll 32 in the other side of the machine. A

similarly adjustable mounting is provided for each of the other suction rolls as well as each of the breast rolls 2% and 30, for the same purpose.

All of the rolls 2-1i23 and lib-33 are positively driven at the same peripheral speed, and a suitable drive arrange ment is shown in FIG. in connection with the rolls 30-33. In FIG. 16, the head 90 of each of the rolls on the drive side of the machine has a drive shaft 99 secured thereto. In order to provide for the desired pivotal movement of the entire roll section as described for changing the, forming Web, each drive shaft 99 is connected by a universal coupling 1% to a floating shaft 101 which is in turn connected by a second universal coupling 1% to a power shaft Hi2 projecting from the gear case 1&3 incorporating suitable gears iii-4 to which the main drive motor 1&5 is connected as indicated in FIG. 10.

The rolls on the side of the machine which is provided with the take-off roll 47 and felt 45 should preferably parts of the. machine, so that. the drive motor 195 may represent the main drive motor for the machine as a whole. The rolls zit-23 in the other section should then bedriven insuch manner as to be accurately synchronized with the rolls Sid-33 so that the forming

webs

25 and 35 travel at identical speeds. A convenient manner of accomplishing this result is to provide the rolls 20-423 with an identical drive arrangement to that shown in FIG. 10 but including a separate drive motor which is then synchronized with themain drive motor 195 as by means of conventional electric tachometers such as are indicated at 1% in FIG. 1.

Within each of the severalsuction rolls is a suction box indicated generally at 1M]; which may be of conventional construction including seals Ill defining the effective suction area of the associated roll, and which may include provision for adjustment as shown in FIG. 5. Thus one endof this suction box is carried by a stub shaft 112 in bearings 113 in the head 99, and the other end is carried by a tubular shaft 115 which projects through the head 91 and carries a worm gear 116 meshing with an adjusting drive worm 117, FIG. 5 also indicates at 118 the adjusting mechanism for the usual deckles (not shown) within the suction roll 22.

The tubular shaft 115 also formsa conduit for conducting White water from the interior of the associated suction roll 22 to a connection 12d into the interior of the casting 66, and this connection incorporates telescoping or otherwise adjustable parts to provide for the laterfl adjusting movement of the suction roll with respect to the casing as, as indicated by the bellows diaphragm 121. From the casting es, the water flows by way of the cross tubes 6763 to the associated casting as, and in order to regulate this flow, and thereby to control the volumetric rate at which the associated suction roll is able to remove water from the sheet, the casting as is provided with adjustable valve means controlling the inlet ends of the cross tubes 67-45%. Thus each of the tubes s7 ss is shown as provided at its inlet end with a valve 123 comprising a rubber covered helical spring arranged for controlled compression by a head member 124 which is threaded on the drive shaft 125 of a control motor 126. Compression of. the valve springs 123 produces gradual throttling of the flow into the associated tubes 6768, and when these spring are fully compressed, the valves are closed.

Special provision is made for assuring adequate sealing between each pair of superimposed rolls and also between the ends of the several rolls in such manner as etlectively to enclose the entire forming chamber. Referring particularly to FIGS. 1 and 3-4, the seal means between each pair of superimposed rolls comprises a rubber covered roll 13% journaled at each end in a slide 131 which is movable generally horizontally in a guide block 132, and each guide block 132 is pivoted at 133 in a mounting 134 on the side of the casting 65 or 66 to permit such pivoting movement of each guide block as may be required to locate the associated seal roll 13% in accurately sealing engagement with each of its associated breast or suction rolls. A spring 135' is mounted between the slide 131 and an adjusting screw 136 in the outer end cover 137 for each guide block 132. The seal rolls 139 are therefore continuously urged into sealing engagement with their associated suction or breast rolls, and it will also be noted in FIG. 1 that one of the seals 111 is located to coincide with each nip of its associated suction roll and a seal roll 130'.

The sealing means at the ends of the suction and breast rolls include a pair of end plates 144 at each side of the machine which cooperate with a pair of vertically extending angles 141 to form a wall as shown in FIG. 6. The phase are of low friction material and engage the ends of the seal rolls 136 and wear rings 142 of low friction material carried by the heads of the several suction rolls as shown in FIG. 5, the outer edges of the plates 140 being cut out to fit around the journals of these rolls while 7 still affording adequate sealing surface. FIG. 8 shows the breast rolls 2% and fill as fitted with an alternative construction of replaceable wear rings M3.

Each of the sealing Walls res-r41 is mounted in yielding engagement with its cooperating sealing surfaces, but it is not necessary to apply particular force to the walls, since in operation they are drawn into increased sealing engagement by the vacuum developed through each sucticn roll. FlGS. 6 and 7 show a mounting arrangement which is satisfactory, and which comprises a plurality of rods 14-4 each having a telescoping mounting in a sleeve 1 85 carried by one of the brackets 93 and in a head lad secured to the adjacent plate 14%. Springs 14? and adjustlug nuts 143 threaded on the rods 14 8 provide the desired biasing force for initially urging the walls 14lll41 into sealing position.

The walls Bid -141 also incorporate cans for maintaining a continuous seal between the opposed outer edge portions of the forming

webs

25 and 35 to prevent lat eral drainage of water from the sheet. Referring to FIG. 8, a thin wall section 15%! of suitable plastic material such as a polyethylene resin is closed at the bottom and clamped between the angles 141 in such manner as to form a tube adapted to be inserted between the opposed edges of the two forming webs. This tube extends up wardly from just above the nip of rolls 23-33 through the forming nip Iii; of the breast rolls, and it is filled with liquid to a somewhat higher pressure than that imposed by the stock between the webs. Under these conditions, the liquid pressure within the tube 15%) tends to balance the water pressure within the forming chamber, while its excess pressure causes the tube to conform to the contour of the space between the forming webs, with its uppermost portion assuming a somewhat rounded cross section while its lowermost portion assumes a flattened contour of practically no thickness. While the tension in the webs is ordinarily sufhcient to maintain them in sealing engagement with the tube 15%, guide blocks 151 of low friction material may be provided on the inner surfaces of the plates Mil for guiding the portions of the webs passing from one roll to the next.

it will thus be seen that the end walls tau-r41 and seal rolls 1% effectively cooperate with the several rolls to enclose the space betwen each pair of vertically disposed rolis. Since provision is made as already described for regulating the effective flow of water from each suction roll, and hence for establishing the desired vacuum conditions in the space above such suction roll, the construction of the invention in effect establishes a plurality of different zones between the breast rolls and the lowest pair of suction rolls and also provides for individual control of vacuum in each of these zones. These conditions result in one of the important advantages provided by this invention, particularly from the standpoint of improved control over the conditions of sheet formation.

Although each forming web has little more than line contact with any of the suction rolls, except for the lowermost rolls 23 and 33, the establishment of suction zones as described makes it possible to remove water through a substantially greater area of the surface of each of the suction rolls, namely over the entire angular area between its nip with the web and the seal roll 1% wnich engages its upper surface. Special additional provision is made by the invention for taking advantage of this fact, by means of one or more deflector plates 155 arranged as shown in FIG. 1 in the spaces above the nip of each horizontally disposed pair of suction rolls, and which are readily mounted in position by means of the guide blocks 151. Each of these deflector plates 155 has its upper edge in close proximity to the

adjacent web

25 or 35, but the remainder of the plate diverges downwardly with respect to the Web so that Whatever water flows out through the web above each one of these plates is deflected away from the web and caused to run onto the upper surface of the associated suction roll well in advance of the line of contact between this roll and the web. Thus a substantial amount of Water can be removed as a given point on the forming web passes from one horizontal pair of rolls to the next, and at the same time there is effective avoidance of the tendency of the water to form a pool immediately above the nip of each pair of suction rolls. in addition, whatever liquid tends to follow the downwardly moving surfaces of the rolls 2il22 and 3tl-32 will either be thrown off onto the upper surface of the next lower roll or will be squeezed oif by the associated seal. roll 13%, and in either case will be removed through such lower roll before it reaches the forming web. 7

The headbox id is shown as constructed in accordance with my application Serial No. 732,324, filed May 1, i958 and assigned to the same assignee as this application.

ple perforations as indicated at 151. This casing lot) is connected at opposite ends to inlet and outlet connections 3M2 and 163 which are in turn supported by brackets res on the uppermost castings 65 and es. Within the casing 16% is a mandrel 165 which tapers to diverge from the inlet connection 16-2 in order to eilect substantially uniform pressure discharge of the incoming stools through the perforations 161 over the entire length of the perforated casing see.

As described in my above application, the mandrel 165 is supported for rotation on a driven shaft 166 connected as indicated at 167 with a drive otor 16$, which is shown in FIG. 10 as conveniently mounted on the gear case 1653, and the mandrel carries a plurality of bars 16% of generally airfoil shape in section which operate to maintain the inner surface of the casing 16b free of particles too large to pass through the perforations 161. Such reject particles are continuously removed for further screening or other treatment by way of the outlet connection 163 through which the excess stock is continuously discharged.

The perforate casing tea is surrounded by an outer casing 17% which receives the screened stock discharged through the perforations ltil, and this casing 1'70 includes the pair of depending

lips

41 and 42 which define the downwardly extending discharge passage 44 as already described. As shown particularly in FIG. 2, these lips are preferably extended downwardly into the upper portion of the nip 33 of the breast rolls 2% and 3t} so that they deliver the screened stock continuously and directly into this nip. FIG. 1 also shows an adjustable mounting for the headboir to shift the lips a l- 52 with respect to the breast rolls, this mounting including a supporting block 1.71 for each bracket 164 having a beveled upper surface which receives the beveled under surface of a saddle member 172 an the bracket. Adjusting screws 1'75 en the saddle member cooperate with the ends of the block 171 to shift the headbox laterally while also raising or lowering it slightly along the beveled surface of the block, and additional provision for lateral shifting of he headbox may be made by means of slots 174 for the bolts 17$ which convert the brackets 164 and blocks 171. This mounting arrangement also facilitates temporary removal of the headbox, by means of a crane and eyebolts 17s, when it is necessary to change the forming webs.

in addition to the advantages which this head-box construction provides in assuring effective screening of the stock in the practically closest location to the breast roll, the construction of the invention in the other parts immediately adjacent the initial forming zone provide further significant advantages. Thus in conventional Fourdrinier machines, special complex provisions must be made to assure maximum uni rmity of relative adjustment between the two slice lips and also the maximum rigidity in the upper lip. With the machine of the invention, such structure is unnecessary, since it is the two breast It includes a cylindrical casing lot; which extends. the full width of the machine and is provided with

rnultirolls

20 and 30 which define the efi ective forming nip and are readily machined to a high degree of uniformity, they can be adjusted by means of their adjustable bearings as described to assure a uniformly precise nip width across the entire width of the machine.

Another important advantage provided by the invention is the effective elimination of entrained air at the forming nip. In the first place, in the operation of a conventional Fourdrinier machine, as the sheet of liquid stock eiiectively leaps from the slice onto the forming wire and breast roll, it enters a zone of relatively stagnant air which produces a backward lag on its topsurface similar to the effect of wind blowing across the surface of a pond. At the same time, the outward flow of stock from the slice creates a zone of relatively low pressure immediately adjacent the upper slice lip into which the surrounding air is drawn, and since this inrush of air is often partially and irregularly obstructed by impediments such as lip adjustments and footwalk brackets, the resulting conditions of nonuniformity may seriously interfere with the desired distribution of the stock across the wire. These conditions increase in severity with increase in the size and speed of the operation of the machine, but they are effectively eliminated in the machine of the present invention, in large measure by reason of the arrangement of the two breast rolls in combination with the discharge lips of the headbox as just described.

Additional control of atmospheric conditions in and immediately adjacent the forming zone is also provided by the structure of the invention which effectively strips the forming webs of entrained air before they receive the stock from the discharge passage 44. Referring particularly to FIGS. 1 and 2, the space above that portion of each of the breast rolls which is moving downwardly to the nip 38 is substantially covered by a

doctor blade

181 or 182 which is shown as secured to the outer surface of the associated

lip

41 or 42 and extends therefrom into close proximity with the top of the adjacent breast roll. Each of these doctor blades thus acts'to skim the majority of the windage from the associated

web

25 or 35 as the latter moves past the outer edge of the blade toward the nip 38, and at the same time the doctor blade cooperates with its associated breast roll and discharge lip to provide a substantially closed chamber 183 or 184- immediately above the nip 38.

In order to complete the prevention of entry of air into these

chambers

183 and 184, means such as a pipe 185 is connected with each of the

chambers

183 and 184 to supply steam thereto at a pressure sufficient for bleeding of the steam back through the slot between the associated doctor blade and breast roll, reference in this connection being made to my copending application Serial No. 745,479, filed June 30, 1958 and assigned to the same assignee as this application. This escaping steam cooperates with the doctor blades to strip all air from the forming webs as they enter the

chambers

183 and 184, and whatever additional steam escapes between the webs and the lips ill and 42 is merely condensed into the stock for subsequent removal during formation of the sheet.

In the operation of this paper machine, therefore, an essentially solid stream of stock is delivered directly to the nip 38 of the breast rolls for downward flow between the two forming

webs

25 and 35, and as it travels toward the lowermost pair of suction rolls, the water is progressively removed by means of the several suction rolls to form the sheet 4-5. Since there is substantially no air present in the stock, and since also the liquid is removed without the passage of air through the sheet, highly desirable structural conditions are established in the sheet. Thus the fines, whether they be short fibers or other small particles, will tend to migrate to the surface of the sheet with the initial water removed, but if the openings in the forming webs are sufficiently small, which is one reason the invention contemplates the use of fabric forming webs, these fines will be trapped at the surfaces of the sheet in such manner as to form'in effect a filter mat on which the remainder of the suspensoids in the stock will be deposited as drainage progresses. In addition, since the order in which the suspensoids move toward the surfaces is progressive in accordance with their sizes, the long fibers will tend to be concentrated in the central layers of the sheet to provide the strongest possible backing for the fine particles which will form the desired smooth outer surfaces. Thus for many purposes, the sheet produced in this manner may be sufficiently smooth for use without additional coating, but if coating is required for a glossy surface or the like, considerably smaller quantities of coating material will be needed than in the case of paper produced by conventional techniques.

The construction of the paper machine of the invention as describes oii'ers additonal practical advantages. In particular, it will be apparent that while the forming machine of the invention is adapted for use wherever a conventional Fourdrinier forming section could be used, and will connect similarly with the subsequent stations of the machine for further handling of the sheet, it has considerably smaller requirements of floor space. Thus F1619 shows a forming section constructed as described in connection with FIGS. 1-8 together with the first press section 200 and [ossociated] associated equipment of a complete paper machine, the parts in dotted lines in FIG. 9 being conventional. FIG. 9 also shows a convenient arrangement for mounting the guide rolls 26 and 36 which serve as stretch rolls for the forming

webs

25 and 35, each of these rolls being mounted on

swingingarms

202 and 203 mounted adjacent the forming section of the machine and provided with fluid pressure cylinders 205 for supplying the desired tensioning force.

- FIG. 9 also illustrates in an effective manner the greatly reduced requirements of fioor space for a forming section constructed in accordance with the invention in comparison with a conventional Fourdrinierforming section. For example, with FIG. 9 drawn in scale to include the portion of the press section of an existing 272-inch newsprint machine, the forming section constructed in accordance with the invention requires 50 feet less floor space lengthwise of the machine than a conventional Fourdrinier forming section. In addition, the forming section of the invention can be increased in height, in order to increase the effective forming length and therefore the available speed range, without altering its requirements of floor space. In fact, this latter objective can be accomplished with particular case by means of the invention, since it requires the mere addition of one or more pairs of suction rolls, and since the invention provides each roll as a modular unit including its own mounting castings 55-46 and connecting tubes 67-68, the incorporation of additional such units requires no change in the basic construction or space requirements.

As just noted, the number of pairs of suction rolls required for a given machine depends upon the-desired speed of operation for the machine, and the size of the individual rolls is also related to the desired speed of operation. Thus for a maximum speed of the order of 600 feet per minute, satisfactory results are obtainable with a single pair of suction rolls in the position of the

rolls

21 and 31 below the breast rolls 20 and 30', and with all four of these rolls 36 inches in diameter. To increase the operating speed, additional pairs of suction rolls are added as described, and with the specific number and arrangement of'rolls shown in the drawings, satisfactory results are obtainable with rolls 36 inches in diameter at speeds at least as high as 1200 to 1500 feet per minute. For greater speeds of operation, if it be found that the increase in centrifugal force due to increased angular speed .of the rolls undesirably affects the inward flow of liquid to the suction rolls, this angular speed and the resulting centrifugal -force can be reduced by appropriate increase in the diameter of the rolls, as

11 can readily be calculated for a desired range of operating conditions.

It should also be noted that the establishment of preferred operating conditions is facilitated by locating vertically adjacent rolls in relatively closely spaced relation, for a number of reasons. As a practical matter, close spacing of the rolls minimizes the size required for the sealing rolls 30 as well as the sealing forces which these rolls must exert, and also it reduces the distances which the forming webs must travel without supporting between adjacent rolls. An additional significant factor related to the vertical spacing of adjacent rolls appears to be the action of the vertically opposed areas of these rolls in tending to throw liquid tangentially outwardly therefrom. Thus with the rolls closely spaced as shown, the tangential discharge of liquid from the lower surface of each ,roll will to a considerable extent tend to strike the upper surface of the adiacent lower roll, and will also tend to meet the tangential discharge from the upper surface of such adjacent roll. The result of these conditions is believed to be either that the downward discharge will tend to be thrown into the lower suction roll in opposition to the outward effects of the centrifugal force of the suction roll, or the opposed streams will tend to neutralize their tangential velocities so that the liquid will be more readily subject to the combined efiects of gravity and suction tending to force it into the interior of the suction roll.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made herein without departing from the scope of the invenion which is defined in the appended claims.

What is claimed is:

1. A paper machine of the character described comprising a pair of breast rolls supported in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, means forming a headbox located on one side of said nip and including a pair of lips defining a discharge passage for stock from said headbox, means supporting said headbox with said lips extending generally vertically substantially within said nip to deliver stock directly from said headbox to said nip, at least one pair of suction rolls associated with said breast rolls respectively, means supporting said suction rolls in generally vertically spaced relation with said breast rolls on the opposite side of said nip from said headbox with each such pair of suction rolls progressively more closely horizontally spaced than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for generally vertical travel in progressively more closely horizontally spaced relation to receive therebetween the stock discharged from said headbox, means associated with said suction rolls for withdrawing and removing liquid from the stock through said webs to form a sheet between said forming webs, and means for receiving and conducting away said sheet from said pair of suction rolls.

2. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, at least one pair of suction rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of suction rolls being progressively more closely horizontally spaced than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means cooperating with said headbox and said rolls to seal the space through which said 12 webs travel between said rolls against escape of liquid laterally of said webs, means associated with said suction rolls for withdrawing and removing liquid through said webs and from said space to form a sheet between said webs, and means below the lowest said pair of suction rolls for receiving and conducting away said sheet.

3. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, at least one pair of [suction} other rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of {suction} other rolls being progressively more closely horizontally spaced than said breast rolls, at least one of the lowermost said pair of other rolls being a suction roll, a pair of separate forming webs trained around associated said breast and [suction] other rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means cooperating with said headbox and said rolls to seal the space through which said webs travel between said rolls against escape of liquid laterally of said webs, [suction means associated with said suction rolls} drainage means for withdrawing and removing liquid through said webs and from said space to form a sheet between said webs, means for controlling said [suction] drainage means [individually for each said suction roll} to establish and maintain predetermined vacuum conditions in the portion of said space [above each said suction rolL] between each said pair of associated rolls, and means below the lowest said pair of [suctionfE other rolls for receiving and conducting away said sheet.

4. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, said frame means including a pair of upright columns at the ends of each of said breast rolls, at least one pair of [suction] other rolls associated with said breast rolls respectively and supported on the associated said columns in generally vertically spaced relation below said breast rolls with each such pair of Emotion} other rolls being progressively more closely horizontally spaced than said breast rolls, at least one of the lowermost said pair of said other rolls being a suction roll, a pair of separate forming webs trained around associated said breast and [suction] other rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means supporting one of said columns in each said pair for rotational movement on a generally vertical axis to support the associated said column and rolls in cantilevered position for changing said forming web thereon, means [associated with said suction rolls'l for withdrawing and removing liquid through said webs to form a sheet between said webs, and means below the lowest said pair of [suctionfi other rolls for receiving and conducting away said sheet.

5. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, at least one pair of Emotion} other rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of Esuctionfd other rolls being progressively more closely horizontally spaced than said breast rolls, or least ne of the lowermost said pair of other rolls being a suction roll, a pair of separate form- 13 ing webs trained around associated said breast and {suction]" other rolls for downward travel in progressively more closely horizontally spaced relation, means forminga headbox supported on said frame means above said breast rolls and including a pair of lips extending downwardly substantially within said nip and defining a discharge passage fordelivering stock from said headbox directly to said nip for downward flow between said forming webs, doctor means extending substantially from the outside of each of said lips to the top of the adjacent said breastroll to skimiwindage airfrom said forming webs approaching said nip and to form with the adjacent said lip a substantially closed chamber overlying said nip, means for supplying steam to each of said chambers at a pressure sufficient to minirnizeentry of air'to said chambers, means [associated with said suction rolls] for Withdrawing and removing'liquid through said webs to form a sheet between said webs, and means below the lowest said pair of [suctionjother rolls'for'receivingand conductingawaysaid-sheet.

6. A paper machine of the character described comprising a" pair of' breast rolls, frame meanssupporting rolls progressively more closely horizontally spaced than said breast rolls, a pair of separate forming Webs trained:

around associated said breast and Esuctio-n] other rolls for downward travel in progressively more closely hori-- zontally' spaced relation to receive therebetween the stock discharged fromv said headbox, means cooperating: with-saidheadbox and said rolls to seal the space through which said webs travel between said rolls against escape of. liquid laterally of said webs, means [associated with said suction rolls] for withdrawing and removing liquid frornthe stock through said webs and from said space to form a sheet between said Webs, at least one deflector member extending above each [ofIsaid pair of [suction]? other rolls in closely spaced and downwardly diverging relation with the adjacent said forming web to direct freely flowing liquid [onto the surface of said suction roll] toward said liquid withdrawingmeans in advance of the nip of the subjncelzt said pair of [suction] other rolls, and means below said [suction] other rolls for receiving and conducting away said sheet.

7. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a [plurality of pairs of suction] pair of couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said [breast rolls with each such pair of suction rolls being progressively more closely horizontally spaced than said} breast rolls, a pair of separate forming webs trained around associated said breast and {suction] couch rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming Webs, means [associated with said suction rolls} for Withdrawing and removing water through said webs to form a sheet between said webs, means above [the lowest said pair of suction] said couch rolls for trimmingsaid sheet to provide trim strips at either side of said sheet, means below one of [the lowest] said {pair of suction] couch rolls for receiving and conducting away said sheet, and means associated with the other of said [lowest pair of suction] couch rolls for eifecting removal of said trim strips from said sheet.

8. A paper machine of the character described comprising a pair or" breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a plurality of pairs of suction rolls associated with said breast rolls respectively and supported on said frame means in generally'vertically spaced relation below said breast rolls with each such pair of suction rolls being progressively moreclosely horizontally spaced than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally edges of saidwebs, suction means cooperating with said suction rolls to withdraw said water from the space defined by eachsaid pair of vertically spaced rolls and the associated said web, and means below the lowest said pair of suction rolls for receiving and conducting away said'sheet.

9. A paper. machine of the character described comprising a pair of breast. rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip. therebetween, a plurality of pairs of suction rolls associated with said,

breast rolls respectively and supported on said frame means in generally verticaliy spaced relation below said, breast rolls with each such pair of suction rollsbeingprogressively more closely horizontally spaced than said breast rolls, a pair of separate forming webs trained,

around associated said breast and, suction rolls for downward travel, in progressively more closely horizontally spaced relation, a headboX supported on said frame means above said breast rolls and including means defining a downwardly extending discharge passage for delivering stock to said nip-for downward flow between said forming webs and outward flow of water through said webs to form a sheet between said webs, rotary means forming a seal between each adjacent pair of said vertically spaced rolls, means forming a wall on either side of said machine in sealed relation with the ends of said rolls and the edges of said webs, suction means cooperating with said suction rolls to withdraw said water from the space defined by each said pair of vertically spaced rolls and the associated said web, means for controlling said suction means individually for each said suction roll to establish and maintain predetermined vacuum conditions in each said space, and means below the lowest said pair of suction rolls for receiving and conducting away said sheet.

10. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a plurality of pairs of' suction rolls associated, with said breast rolls respectively and supported on saidframe means in generally vertically spaced relation below said breast rolls with each such pair of suction rolls being progressively more closely horizontally spaced than said breast rolls, a pair of separate formingwebs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said frame means above saidbreast rolls and including means defining a downwardlyextending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward flow of water through. said webs to form a sheet between said webs, rotary means forming a seal between each adjacent pair of said vertically spaced rolls, means forming a wall on either side of said machine in sealed relation with the ends of said rolls and the edges of said webs, suction means cooperating with said suction rolls to withdrawn said water from the space defined by each said pair of vertically spaced rolls and the associated said web, deflector means in each said space extending above each said suction roll in close relation with said Web for directing freely llowing water onto the surface of said suction roll in advance of the area of contact of said roll with said web, and means below the lowest said pair of suction rolls or receiving and conducting away said sheet.

11. A paper machine of the character described comprising two pairs of base pedestals, a plurality of pairs of castings mounted on said pairs of pedestals respectively to form two pairs of columns, a {pair of] breast roll Strollers mounted at the top of each said pair of columns with said breast rolls closely spaced in a horizontal plane to define a vertically extending nip therebetween, a suction roll supported by each said pair of castings in generally vertically aligned relation below the associated said breast roll and with each of the resulting pairs of suction rolls being progressively more closely spaced in a horizontal plane than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said columns above said breast rolls and including means defining a downwardly extending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward flow of liquid through said webs to form a sheet between said webs, means directly connecting all of said castings in a first column of each said pair of columns for free flow of liquid therebetween, means for connecting each said first column with a source of suction, means connecting the interior of each of said suction rolls with the associated said casting in the second column of the associated said pair of columns, and a tube connecting each casting in each said second column with the associated casting in the associated first column for conducting thereto liquid from the associated said suction roll.

12. A paper machine of the character described comprising two pairs of base pedestals, a plurality of pairs of castings mounted on said pairs of pedestals respectively to form two pairs of columns, a Elpair offi breast roll [rolls] mounted at the top of each said pair of columns with said breast rolls closely spaced in a horizontal plane to define a vertically extending nip therebetween, a suction roll supported by each said pair of castings in generally vertically aligned relation below the associated said breast roll and with each of the resulting pairs of suction rolls being progressively more closely spaced in a horizontal plane than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said columns above said breast rolls and including means defining a downwardly extending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward flow of liquid through said webs to form a sheet between said webs, means directly connecting all of said castings in a first column of each said pair of columns for free flow of liquid therebetween, means for connecting each said first column with a source of suction, means connecting the interior of each of said suction rolls with the associated said casting in the second column of the associated said pair of columns, a tube connecting each casting in each said second column with the associated casting in the associated first column for conducting thereto liquid from the associated said suction roll, and valve means associated with each said tube for controlling the flow therethrough to establish and main tain predetermined vacuum conditions in each of said suction rolls.

13. A paper machine of the character described comprising two pairs of base pedestals, a plurality of pairs of castings mounted on said pairs of pedestals respectively to form two pairs of columns, a Epair of? breast roll {rolls} mounted at the top of each said pair of columns with said breast rolls closely spaced in a horizontal plane to defined a vertically extending nip therebetween, a suction roll supported by each said pair of castings in generally vertically aligned relation below the associated said breast roll and with each of the resulting pairs of suction rolls being progressively more closely spaced in a horizontal plane than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said columns above said breast rolls and including means delining a downwardly extending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward how of liquid through said webs to form a sheet between said webs, means directly connecting all of said castings in a first column of each said pair of columns for free how of liquid therebetween, means for connecting each said first column with a source of suction, means connecting the interior of each of said suction rolls with the associated said casting in the second column of the associated said pair of columns, a tube connecting each casting in each said second column with the associated casting in the associated first column for conducting thereto liquid from the associated said suc tion roll, and means supporting each of said first columns for rotational movement about a generally vertical axis on the associated said pedestal to support the associated said second column and rolls in cantilevered position for changing said forming web thereon.

14. A paper machine of the character described comprising two pairs of base pedestals, a plurality of pairs of castings mountedon said pairs of pedestals respectively to form two pairs of columns, a [pair of] breast fijrolls] roll mounted at the top of each said pair of columns with said breast rolls closely spaced in a horizontal plane to define a vertically extending nip therebetween, a suction roll supported by each said pair of castings in generally vertically aligned relation below the associated said breast roll and with each of the resulting pairs of suction rolls being progressively more closely spaced in a horizontal plane than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said columns above said breast rolls and including means defining a downwardly extending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward flow of liquid through said webs to form a sheet between said webs, means directly connecting all of said castings in a first column of each said pair of columns for free flow of liquid therebetwee i, means for connecting each of said first column with a source of suction, means connecting the interior of each of said suction rolls with the associated said casting in the second column of the associated said pair of columns, a tube connecting each casting in each said second column with the associated casting in the associated first column for conducting there to liquid from the associated said suction roll, means cooperating with said rolls to enclose the spaces defined by each pair of vertically aligned said rolls and the associated said forming webs, deflector means in each said space extending above each said suction roll in close relation with said web for directing freely flowing water onto the surface of said suction roll in advance of the area of contact of said roll with said web Eijwirefi, and means below the lowest pair of said suction rolls for receiving and conducting away said sheet.

15. A paper machine of the character described comprising two pairs of base pedestals, a pair of columns mounted on said pairs of pedestals respectively, a [pair of] breast [rollsffi roll mounted at the top of each said pair of columns with said breast rolls closely spaced in a horizontal plane to define a vertically extending nip therebetween, a plurality of pairs of suction rolls supported by said pairs of columns in generally verticallyspaced relation below said breast rolls and with each of said pairs of suction rolls being progressively more closely spaced in a horizontal plane than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, a head box supported on said columns above said breast rolls and including means defining a downwardly extending discharge passage for delivering stock to said nip for downward flow between said forming webs and outward how of liquid through said webs to form a sheet between said Webs, means in a first column of each said pair of columns defining a conduit for free how of liquid there through, means for connecting each said conduit with a source of suction, means in the second of each said pair of columns defining a plurality of compartments each connected with the interior of one of said suction rolls, a tube connecting each said compartment with the associated first column for conducting thereto liquid from the associated said suction roll, means for individually regulating the liquid flow through each of said tubes, and means below the lowest pair of said suction rolls for receiving and conducting away said sheet.

16. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, at least one pair of suction rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of suction rolls being progressively more closely horizontally spaced than said breast rolls, a pair of separate formin webs trained around associated said breast and suction rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls and including a pair of lips defining a downwardly extending discharge passage for delivering stock from said headbox to said nip for downward flow between said :tormin web and drainage therethrough, means including walls cooperating with the ends of said rolls to enclose the spaces defined by each pair of vertically aligned said rolls and the associated said forming web, means cooperating with said walls to form seals between the opposed edge portions of said webs, means associated with said suction rolls for withdrawing and removing liquid from said spaces to form a sheet between said Webs, and means below the lowest said pair of suclion rolls for receiving and conducting away said sheet.

17. A paper machine as defined in claim 16 wherein said seal forming means comprise a tube of flexible material positioned between said opposed side edge portions of said forming webs at each side of said webs, and means for maintaining said tubes filled with liquid at a higher pressure than the pressure exerted laterally on said tubes by said stock.

18. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetwecn, at least one pair of [suctionjl other rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of {suction} other rolls being progressively more closely horizontally spaced than said breast rolls, at least one of the lowermost said pair of other rolls being a suction roll, a pair of separate forming webs trained around associated said breast and [suctionfi other rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said frame means above said breast rolls and extending the full width of said {wires} webs, a pair of lips depending from said headbox substantially into said nip to define a downwardly extending discharge passage for delivering stock from said headbox to said nip for downward flow between said forming webs, means cooperating with said lips and said breast rolls to enclose a chamber overlying said nip on either side of said lips and to minimize access of air to said chambers, means cooperating with said headbox and said rolls to seal the space through which said webs travel between said rolls against escape of liquid laterally of said Webs, means [as sociated with said suction rolls} for withdrawing and removing liquid through said webs and from said space to form a sheet between said webs, and means below the lowest said pair of isuction} other rolls for receiving and conducting away said sheet.

19. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, at least one pair of Eisuctionfi other rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls with each such pair of [suctionll other rolls eing progressively more closely horizontally spaced than said breast rolls, at least one of the lowermost said pair of other rolls being a suction roll, a pair of separate formwebs trained around associated said breast and @suctionfi other rolls for downward travel in progressively more closely horizontally spaced relation, a headbox supported on said frame means above said breast rolls and extending the full width of said {wiresfi webs, a pair of lips depending from said headbox substantially into said nip to define a downwardly extending discharge passage for delivering stock from said headbox to said nip for downward flow between said forming Web, means cooperating with said headbox and said rolls to seal the space through which said webs travel between said rolls against escape of liquid laterally of said webs, means within said headbox for effecting continuous screening of the stock entering said discharge passage, means Eassociated with said suction rollsfi for withdrawing and removing liquid through said webs and from said space to form a sheet between said webs, and means below the lowest said pair of {suction} other rolls for receiving and conducting away said sheet.

20. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a'horizontal plane to define a vertically extending nip therebetween, a pair of Esuctionfi c0uc/Z,r0l1s associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls and in more closely horizontally spaced relation than said breast rolls, at least one of said couch rolls being a suction roll, a pair of separate forming webs trained around associated said breast and [suction] couch rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means establishing a plurality of {suction} drainage zones on up posite sides of said webs between said breast rolls and said Fisuctionl couch rolls, means cooperating with said rolls and said webs to seal said zones against escape of liquid laterally of said webs, [suction means for applying suction to] controllable means for efiectz'ng drain. age from said zones to Withdraw and remove liquid through said webs to form a sheet between said webs, means for regulating said [suctionji controllable means individually for each of said zones, and means below said cases pair of [suction] couch rolls for receiving and conducting away said sheet.

- 21. A paper machine of the character described co m prising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of suction rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation with said breast rolls and in more closely horizontally spaced relation than said breast rolls, a pair of separate forming webs trained around associated said breast and suction rolls for generally vertical travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means on the opposite side of said nip from said suction rolls for delivering stock to said nip for flow between said forming wires, means establishing a plurality of suction zones on opposite sides of said webs between said breast rolls and said suction rolls, means cooperating with said rolls and said webs to seal said zones against escape of liquid laterally of said webs, suction means for applying suction to said zones to withdraw and remove liquid through said webs to form a sheet between said webs, means for regulating said suction means individually for each of said zones, and means associated with said pair of suction rolls for receiving and conducting away said sheet. 1

22. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of [suction] couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls and in more closely horizontally spaced relation than said breast rolls, or least one of said couch rolls being a suction. roll, a pair of separate forming webs trained around associated said breast and [suction] couch rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means cooperating with said breast rolls for substantially preventing entrainment of air with said stock and the portions of said forming webs entering said nip, means establishing a plurality of [suction] drainage zones on opposite sides of said webs between said breast rolls and said [suction] couch rolls, means cooperating with said rolls and said webs to seal said zones against escape of liquid laterally of said webs, [suction means for applying suction to] c ntrollable means for effecting drainage from said zones to withdraw and remove liquid through said webs to form a sheet between said webs, means for regulating said [suction] controllable means individually for each of said zones, and means below said pair of [suction] couch rolls for receiving and conducting away said sheet.

23. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a [plurality of pairs of suction] pair of other rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls [with each said pair of suction rolls being progressively] and more vclosely horizontally spaced than said breast rolls, a pair of separate forming webs trained around associated said breast and [suction] other rolls for downward travel in progressively more closely horizontally spaced relation, means forming a headbox supported on said frame means above said breast rolls and including a pair of lips defining a downwardly extending discharge passage for delivering stock from said headbox to said nip for downward flow between said forming webs and drainage therethrough, means including walls cooperating with the ends of said rolls to enclose the spaces defined by each pair of vertically aligned said rolls and the associated said web, means cooperating with said walls to form seals between the opposed edge portions of said webs, means [associated with said suction rolls] for withdrawing and removing liquid from said spaces to form a sheet between said Webs, a plurahty of deflector plates arranged in each of said spaces in vertically spaced relation with each other, each of said deflector plates having the upper edge thereof adjacent one of said forming webs and having the remainder there of in diverging relation with said web to direct freely flowing water [onto the surface of the subjacent said suction roll], away from said web and toward said liquid withdrawing moons, and means below the lowest said pair of [suction] couch rolls for receiving and conducting away said sheet.

24. A paper machine of the character described com prising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls, a pair of separate forming webs trained around associated said breast and couch rolls for downward travel from said breast rolls to said couch rolls, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, said couch rolls being positioned in more closely horizontally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly from the space between said webs at substantially equal rates and thereby to efiect formation in said space of a sheet having outer surface layers on both sides thereof which are substantially identical in composition and texture, means for efiectiug removal of the drained water from within the l op of each said web, means for causing said webs to loop said couch rolls respectively and thereby to diverge from each other, and means for receiving and conducting the sheet away from said couch rolls.

25. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaccd relation below said breast rolls, a pair of separate forming webs trained around associated said breast and couch rolls for downward travel from said breast rolls to said couch rolls, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, said couch rolls being positioned in more closely horiz ntally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly through said webs into said chambers at substantially equal rates and thereby to effect formation of a sheet between said webs having outer surface layers on both sides thereof which are substantially identical in composition and texture, means for eficctiiig removal 0 the drained water from within the loop of each said web, means for causing said webs to loop said couch rolls respectively and thereby to diverge from each other, and means for causing the sheet to remain on a predetermined one of said webs around a portion of the associated said couch roll and thereby to separate from the other said web.

26. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls, a pair of separate forming webs trained around associated said breast and coach rolls for downward travel from said breast rolls to said couch rolls, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between and forming webs, said couch rolls being positioned in more closely horizontally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly from the space between said webs at substantially equal rates and thereby to effect formation in said space of a sheet having outer surface layers on both sides thereof which are substantially identical in composition and texture, means for efiecting removal of the drained water from within the lop of each said web, means for causing said webs to loop said couch rolls respectively and thereby to diverge from each other, a transfer roll below one of said couch rolls, a felt looping said transfer roll, said one couch roll having a suction box therein arranged to hold the sheet on the associated said web as said webs diverge, and means guiding s id felt into engagement with the sheet to remove the same from said associated web.

27. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of coach rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls, a pair of separate forming webs trained around associated said breast and coach rolls for downward travel from said breast rolls to said couch rolls, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means for preventing entrainment of air with said webs and stock into said nip of said breast rolls, said couch rolls being positioned in more closely horizontally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly from the space between said webs at substantially equal rates and thereby to efiect formation in said space of a sheet having outer surface layers on both sides thereof which are substantially identical in composition and texture, means for effecting removal of the drained water from within the loop of each said web, means forming seals between the edges of the downwardly traveling portions of said webs preventing lateral flow of liquid from said space and entry of air to said space, means for causing said webs to loop said couch rolls respectively and thereby to diverage from each other, and means for receiving and conducting the sheet away from said couch rolls.

28. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip the-rebetween, a pair of couch rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls, a pair of separate forming webs trained around associated said breast and coach rolls for downward travel from said breast rolls to said couch rolls, means forming chambers each having one side thereof defined by the downwardly traveling portion of one of said webs, means forming a headbox supported on said frame means above said breast rolls for delivering stock downwardly to said nip for downward flow between said forming webs, means forming seals between said chambers preventing lateral flow of water from the space between said webs and entry of air to said space, said couch rolls being positioned in more closely horizontally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly through said webs into said chambers at substantially equal rates and thereby to eflect formation of a sheet between said webs having outer surface layers on both sides thereof which are substantially identical in composition and texture, means for efiecting removal of the drained water from within the loop of each said web, means for causing said webs to loop said couch rolls respectively and thereby to diverge from each other, and means for causing the sheet to remain on a predetermined one of said webs around a portion of the associated said couch roll and thereby to separate from the other said web.

29. A paper machine of the character described comprising a pair of breast rolls, frame means supporting said breast rolls in closely spaced relation in a horizontal plane to define a vertically extending nip therebetween, a pair of coach rolls associated with said breast rolls respectively and supported on said frame means in generally vertically spaced relation below said breast rolls, a pair of separate forming webs trained around associated said breast and coach rolls for downward travel from said breast rolls to said couch rolls, a headbox, means supporting said headbox above said breast rolls in position to deliver stock downwardly to said nip for downward flow between said forming webs, said couch rolls being positioned in more closely horizontally spaced relation than said breast rolls and in predetermined aligned relation with said breast rolls such that said webs converge downwardly at substantially equal angles to the vertical to cause the water in the stock to drain outwardly from the space between said webs at substantially equal r tes and thereby to efiect formation in said space of a sheet having outer surface layers on both sides thereof which are substantially identical in composition and texture, a plurality of deflector members positioned in vertically spaced relation within the loop of each said web and in closely spaced and downwardly diverging relation with the adjacent said web to deflect water flowing through said web downwardly and away from said web, means for effecting removal of such deflected water from within the loop of each said web, means for causing said webs to loop said couch rolls respectively and thereby to diverge from each other, and means for receiving and conducting the sheet away from said couch rolls.

References Cited in the file of this patent or the origlnal patent UNITED STATES PATENTS 57,192 Russell Aug. 14, 1866 214,250 Gregg Apr. 15, 1879 1,500,208 Shaw July 8, 1924 1,661,678 Price Mar. 6, 1928 1,718,574 Millspaugh June 25, 1929 1,782,215 Sheperd Nov. 18, 1930 1,817,594 Wagner et a1. Aug. 4, 1931 1,875,075 Mason Aug. 30, 1932 2,167,440 Mason July 25, 1939 2,554,968 Thompson May 29, 1951 2,823,593 Holden Feb. 18, 1958 2,881,669 Thomas et al Apr. 14, 1959 2,977,277 Kelly Mar. 28, 1961 FOREIGN PATENTS 2,477 Great Britain July 9, 1875