US2850951A

US2850951A - Paper-making machines

Info

Publication number: US2850951A
Application number: US431194A
Authority: US
Inventors: Holden Herbert
Original assignee: Beloit Iron Works Inc
Current assignee: Beloit Iron Works Inc
Priority date: 1953-06-17
Filing date: 1954-05-20
Publication date: 1958-09-09
Anticipated expiration: 1975-09-09

Description

Slept. v9, 1958 H HOLDEN 2,850,951

PAPER-MAKING MACHINES FileqAMay 20, 1954 5 sheets-sheet 1 l nventor Herberz HQ/de Sept.4 9, 1958 H. HOLDEN 2,850,951

PAPER-MAKING MACHINES Filed May 2o, 1954 l5 sheets-sheet 2 Inventur ttorney Sept. 9, 1958 H. HOLDEN PAPER-MAKING MACHINES Filed May 2o, 1954 5 Sheets-sheet :s

ibi I? 950 Herbal?? bro/den By Wr Y h- Attorney Sept. 9, 1958 l H. HOLDEN 2,850,951

' PAPER-MAKING MACHINES Filed May 2o, 1954 5 sheets-sheet 4 Herbert den A (torn ey sept. 9, 195s H. HOLDEN 2,850,951

PAPER-MAKING MACHINES Filed May 2o, 1954 5 sheets-sheet 5 l Inventur United StatesvPatent O PAPER-MAKING MACHINES Herbert Holden, Sheffield, England, assignor to Beloit Iron Works, Beloit, Wis., a corporation of Wisconsin This invention relates to paper-making machines of the Fourdrinier type in which the paper web is taken from the forming wire by a vacuum pick-up roll and thereafter transferred to the press section of the machine.

In some machines, the vacuum pick-up .roll (operating within a transfer felt) is the lowermost roll of a stacked press, at the upper rolls of which the web is subjected to pressing and transferred to the upper side of a felt by which it is progressed further through the machine. In other machines, the web is carried on the underside of the transfer felt to which'it has been taken 'from the forming wire by the vacuum pick-up roll, and meets a bottom felt at `or somewhat before reaching the nip of a transfer press consisting of a bottom suction roll and a top press roll, and substantially removed in space from the pick-up roll. As its name indicates, this press serves primarily for the transfer of the web to the upper side of the bottom felt, andfurther pressing is effected at a separate press to which the web is carried by the bottom felt, with still further pressing effected subsequently if desired. i

The present invention is concerned with'a modification of the second of the vacuum pick-up arrangements described above, and is directed to a simplification of the main essential mechanism, and to the improved supporting of the web removed from the wire.

According to the present invention, a Fourdrinier paper-making machine of the type in which la lsuction pick-up co-operates with the forming wire in the vicinity of the couch roll to remove the paper web, and a bottom felt is provided to carry the web to a press, comprises a suction transfer roll disposed near to the suction pickup roll o-n the side of the pick-up roll remote from the couch roll, an lendless bottom transfer lfelt passing round the transfer roll, an endless permeable pick-up medium passing round the pick-up roll, and a guide roll to cause the pick-up medium to curve round part of the transfer roll onpleaving the pick-up roll, and .then to diverge from the transfer felt when the web and the felt have left the transfer roll.

When the web has Ibeen removed yfrom the wire by the pick-up roll, it is carried by the pick-up medium into contact with the transfer felt over the arc of .the transfer roll round which the pick-up medium curves, and suction applied by the transfer roll causes the web to leave the pick-up medium and remain on the upper side of the transfer felt as the pick-up medium and the felt diverge. The web thus becomes supported by the transfer felt very soon after it has been removed by the .pick-up roll from the wire; and, being applied to the transfer felt close to the pick-upy point, it may be carried by that felt direct to a press, a transfer press being rendered unnecessary.

Th-e transfer roll may be so positioned as to form a nip with the pick-up roll, with the pick-up medium and the transfer felt (and the web between them when the machine is in operation) interposed between them. Such nip is not intended for material expression of water, but mainly to assist in the transfer of the web, forwhich purpose the pressure between the rolls is only comparatively light, say not exceeding 40 lbs. per linear inch.

Alternatively, there may be a gap between the pickup roll and the transfer roll, which gap is bridged vby the pick-up medium'as it leaves the pick-up roll to meet the transfer felt at the transfer roll. The web is then subjected to pressure exerted solely by the arcs ofthe pick-up medium and the transfer felt round the transfer roll, sufiicient exibility being provided to pass lumps and variations in thickness or creases in the felt without the same likelihood of damage that might arise in' passage through a positive nip between the two rolls.

The pick-up medium may,` be an endless felt. It is, however, an important advantage of the invention that an endless pick-up wire may be used, where the paper is of a quality which is no detriment to have two wire sides. The useof a pick-up wire, with its open texture, avoids the cleaning diculties encountered with a transfer felt.

The endless wire may be inserted by methods generally analogous to those used for the insertion of the endless forming wire at the wet end of the machine, several alternative methods Ibeing described below.

The invention will now be ldescribed in greater detail with reference to the accompanyingdrawings, in which Figure 1 is a side elevation, partly yin section, ofthe pick-up and first press section of .a machine witha transfer roll disposed as shown in the -diagrammatic Figure 7;

Figure 2 corresponds to part of Figure l, and shows the disposition of the machine parts for wire changing, the old wire removed and new wire in place for installation, with special equipment for the purpose; l f

Figure 3 shows the special equipment of Figure 2 ready to receive the transfer wire from the side of the machine; -f

Figure 4 is a section taken on the line 4-4 of Figure 3, with parts broken away; n

Figure 5 corresponds to Figure 2, but shows modified pick-up roll mechanism and alternative `disposition of machine parts for wire changing and other special equipment;

Figure 6 again corresponds to Figure 2, but `shows Ifurther modified pickup rmechanism and wire changing disposition and equipment; and

Figures 7 to 18 show diagrammatically various dispositions of pick-up roll and transfer roll in relation to each other and to the couch roll (in some instances with a forward drive roll for the forming wire), Figure 7 being the disposition shown in Figures 1, 5, and 6.

In Figure 1, a suction transfer roll 20 is mounted in fixed bearings in a housing 21 beyond a forward drive roll 22 for the forming wire 23 beyond the couch roll 24.y A transferfelt 25 passes substantially vertically (at 26) to the side of the transfer roll 20 nearest to the forward drive roll 22, and from the transfer roll it passes upwardly at a slight incline to the nip of a suction press comprising a bottom suction roll 27 and a plain press roll 28. Leaving the nip, the felt 25 returns via guide rolls 29 and stretching and cleaning devices'30, 31 to the transfer roll. A savefall tray 32 may Ibe disposed lbelow the transfer roll, as shown in-Figure 7; alternatively, with no`tray, the felt may return horizontally to the roll, as shown at 33 in Figure 9.

A suction pick-up roll 34 is carried in a pair of arms 35 (one only shown) pivoted at 36 lintermediately of ltheir length on a lcam shaft 37, rotation of which by racks 38 and pinions 39 operated by air cylinders 404er the like provides` for. quick lifting of the roll 34 from l contact with the run 4,1 of the wire 23 between the couch Patented Sept. 9, 1958 3 roll 24 and the forward drive roll 22. The upper ends 42 of the arms 35 are urged by air cylinders 43 or the like to provide an adjustable nip with the rubber covered transfer roll 20, which nip need not be broken by the quick lift of the pick-up roll from the wire on operation of the cylinders 40.

An endless pickup wire 44 passes downwards to the side of the pick-up roll 34 nearest the couch roll 24, under the pick-up roll 34, and over the transfer felt 25 on the transfer roll 26. Diverging at 45 from the transfer felt, the pick-up wire 44 passes a cleaning spray 46 and tray 47 to a stretch roll 48 on arms 49 pivoted at 50 and loaded by springs 51, and thence by guide rolls 52 to the pick-up roll 34. Y

The pick-up roll 34 has its internal suction box of usual construction sealed to the inside of the perforated shell 53, of the roll to provide a mouth 54 extending over a short arc from approximately the first meeting of the pick-up wire 44 with the forming wire run 41. This arc is followed by a further suction-box mouth arc 55 extending to the point at which `the pick-up wire 44 is about to leave the pick-up roll 34. This second arc 55 may be supplied with a lower degree of suction, to keep attached to the picloup wire the web of paper already removed from the forming wire run 41 with the aid of higher suction at the first arc 54, and to prevent water entrained in the holes of the shell 53 being thrown back into the pick-up wire and web.

The transfer roll 20 has a compartment 56 in its suction box, sealed to the inside of the perforated metal shell 57 of the roll to provide a mouth extending over an arc from approximately the first contact of the transfer felt 25 with the perforated rubber cover 58 and the paper web with the pick-up wire 44 to near the point 45 at which the transfer felt 25 and the run 41 of the pick-up wire begin to diverge, thus ensuring transfer of the web to the felt 25. When, however, the machine is arranged with a definite nip between the rubber covered transfer roll 20 and the pick-up roll 34 (see Figures 1, 2, 5, 6, 7, 8, l1, l2, l5, and 16), a further compartment 56A may also be provided at the inlet side of the nip to remove any expressed water.

The arc of contact of the pick-up wire 44 over the transfer roll 20 is determined by the position of the stretch roll 48. There may, however, be an auxiliary guide roll 59 (Figure 9) between the transfer roll 20 and the stretch roll 48, and close to the transfer roll, to control this arc.

The paper web (which the drawings do not attempt to show) follows a sinusoidal path from the point at which it is removed from the forming wire run 41 to the point at which it has left the pick-up wire run 41 for the transfer felt run 25, i. e., in an arc convex downwardly as it passes round the pick-up roll 34 and then in an arc of reverse curvature as it passes round the transfer roll 20, This form of path results with various relative height dispositions of the axes of the couch roll, the pick-up roll, and the transfer roll. In general, the pick-up roll, less in diameter than the couch roll, has the lowermost part of its surface at approximately the same height as ythe axis of the couch roll, but it may be above or below this height. Figures 7 to 18, to be described later, show the pick-up roll in various relationships to the couch roll and the transfer roll.

Worm and screw-and-

nut gear

60, 61, operated by handwheel 62, is connected to the upper ends 42 of the pick-up roll arms 35 (after disconnection of the cylinders 43: see Figure 2) to swing the roll 34 well clear of the forming wire run 41'for changing of the pick-up wire 44. The rolls 52 are supported by beams 63 on pedestals 64 including removal pieces 65 from side frames 66 of the press section (see Figure l; also Figure 4). The beams 63, connected by crossbeams 67, also carry the

gearing

60, 61, 62 for the arms 35, and `

disconnectible gearing

68, 69 for the loading spring 51 of the stretch roll 48. For wire-changing, the weight on the beams 63 is taken by beams 70 inserted into the machine, after the pick-up roll 34 has been swung upwardly, the loose pieces 65 removed, and the stretch roll 48 detached from its arms 49 and laid behind brackets 71 on the beams 63. The beams 70 rest at one end on tie beams 72 between the beams 67; their other ends extend across the aisle alongside the machine, where they are supported on a frame 73 (Figure 4), the beams 67 then not being supported wholly by the machine frame, but with the beams 70 providing a continuous support from the frame 73 across the aisle and through the machine to the farther side frame 66A of the machine. The beams 70 are brought into position by suspension cables 74 from a crane or run-ways.

Between the frame 73 and the nearer side 66, two pairs of

pedestals

75, 76 provide a support for a frame 77 having brackets 78 to receive poles 79 round which the new pick-up wire 44A is draped. Initially, the poles 79 are compactly disposed in brackets 80 and on crossmembers 81, all well within the compass of the frame 77. The beams 70 are inserted through the wire, and supported as previously described. The poles 79 are then transferred to the brackets 78, so that the wire 44A is draped around five poles (Figure 2).

The frame 77 is then lifted by a crane clear of the pedestals 75, 76 (Figures 3 and 4) and carried from the aisle across the machine, when it is lowered on to supports 82 (Figure 2), the draped wire passing round the whole of the mechanism supported by the

beams

67, 70. The wire 44A is then taken from the poles 79, and the frame 77 is removed, for the machine mechanism to be restored to its original position, the beams 70 being removed after'replacement of the removable parts 65.

In Figure 5, instead of the pick-up roll being quickly lifted, as in Figure l, the forward drive roll 83 may be quickly lowered as shown at 83A to break the contact between the forming wire run and the pick-up roll 34. On starting up the machine and when a break occurs, thc drive roll is raised to control the lap of the wire run -41 round the roll 34. The nip of the pick-up roll 34 and the transfer roll 20 is controlled by cylinders 84, the roll arms 85 being pivoted at 86. Upon disconnection of the cylinders S4, the pick-up roll 34 may be lifted by a crane until notches 87 in the arms 85 are engaged by automatic stops 88. The stretch roll 89 is carried by a slide 90, which may be moved along support beams 91 to the position shown at 90A. The beams 91 may then be supported in the manner described with reference to Figures l to 4, for the application of a new wirc 92 draped on a frame 93 similar to the frame 77. It is not necessary to lower the roll 83 for changing of the wire 92.

In Figure 6, which again shows a forward drive roll 94 adapted to be lowered (94A) to break contact between the forming wire run 41 and the pick-up roll 34, the pick-up arms 95 are pivoted to allow the pick-up roll to be raised into line with a cantilever frame 97 at the rear of the machine, one arm being capable of being divided by removal of a part 96 to enable the roll 34 and the remaining part 95A of that arm to be detached from the main part of the arm. The arms 95 can be discon nected from their loading cylinders 95B and swung so that a locking pin may be inserted in holes 95C, 95D in the arms and machine frame respectively, which brings the roll 34 to the position Vshown in chain lines. ln this position, one end of the roll 34 may be supported by a beam 97A cantilevered from the frame 97, after which the part 96 may bc removed to divide the arm 95. The stretch roll 98 and guide rolls 99 are similarly taken to the frame -97 and attached to it by one end. The rolls thus cantilevered from the frame lie opposite a new wire 100 draped from poles 101 carried by a frame 102 from a runway or crane. The beam 97A is threaded through the wire vand into engagement with the roll 34 before the arm 95 is divided. The wire is then carried inwards by the frame 102 over the

rolls

34, 98, 99, after which the part 96 is re-inserted in the arm 95 and the beam 97A is removed. The wire may now be completely unrolled, the rolls 9S, 99 being returned to their working positions and the arms 95 swung until the cylinders 95B can be reconnected.

The pick-up roll is preferably positively driven, for example by means of a self-contained motor movable with the roll. Again, it may be driven through a flexible coupling allowing sufficient movement for the quick-lift of the pick-up roll itself (where provided, as in Figures 1 and 2) and capable of being disconnected for Athe substantial movement of the roll required in wirechanging. Yet again, the pick-up roll may be driven from a shaft co-axial with the transfer roll through toothed gearing capable of swinging with the pick-up roll Without coming out of mesh during the relatively small quick lift. y

Figures 1, 5, and 6 show the diameter of the transfer roll 20 to ibe approximately equal to (actually. slightly less than) that of the couch roll 24. In Figures 7 to 18, its diameter lies more nearly intermediately between those of the couch roll and the pick-up roll 34. In other respects, Figure 7 corresponds to Figures l, 5, and 6.

Considerable latitude is possible in the respective heights of the axes of the pick-up roll 34, the transfer roll 20, and the couch roll 24. Variations in these respective heights and other possible varations in the pick-up and transfer arrangements are shown in Figures 7 to 18, some of which show the pick-up taking place at the couch roll, instead of from a run of the forming wire between the couch roll and a forward drive roll.

f' Figure 7 calls forno further description, since it generally corresponds to Figures 1, 5, and 6, except to point out that it shows the axis 103 of the transfer roll 20 substantially below the level of the axis 104 of the pick-up roll 34.

In Figure 8, the axis 103 is at nearly the same height as the axis 104,k and this provides greater clearance 105 between the forward drive roll 22 and the upward run 106 of the transfer felt, which run may depart more from the vertical to increase this clearance still further.

Figure 9 differs from Figure 7 principally in having the pick-up roll 34 and the transfer roll 20 sufficiently clear of each other by a gap 107 to avoid a direct nip. The wire 44 has a run 108 between leaving ythe roll 34 and meeting the felt 25 at the roll 20, thus bridging the gap 107. The suctionbox mouth 109 of the roll 20 is narrower in consequence. An auxiliary guide roll 59 serves to control the length of arcuate contact of the wire run 45 with the roll 20.

Figure l0 generally resembles Figure 9, lbut has the transfer roll axis 103 nearly level with the pick-up roll axis 104.

Figure 1l shows the wire 44 first passing over an advance guide roll 110 before reaching the pickup roll 34 (as described in U. S. patent application Serial No. 420,132 of Herbert Holden, entitled Paper-Making Machines, filed March 31, 19.54) the guide roll and the pick-up roll both lying `clear of the couch roll 24 of the forming wire by an amount greater than the thickness of the pick-up wire 44 to provide that a straight line tangential to the other wire surface at both

rolls

110 and 34 would, for a portion of its length, form a chord of the circle provided by the lap of the forming wire 23 round the couch roll 24. This permits lumps in the paper web to pass, likewise any variation in thickness of the wire 44, with less likelihood of damage to the web. The couch roll 24 has a suction box mouth 111 extending into the overlap of the pick-up wire 44 and the .forming wire 23 for the removal of expressed water. This is followed by a` further month 112 for a ow of pressure air from within the roll 24 to assist in the removal of the web from the forming wire 23 just in advance of the first contact of the pick-up wire 44 with the pick-up roll 34.

Figure 12 is similar to Figure 11 in having the advance guide roll 110, but the transfer roll axis 103 is nearly level with the pick-up roll axis 104.

Figures 13 and 14 resemble Figures l1 and l2 respectively, but also have the gap 107 between the pick-up roll 34 and the transfer roll 20, bridged by the run 108 of the transfer wire 44, thus avoiding fa direct nip at either pick-up or transfer. Again, an auxiliary guide roll 59 is used to control the transfer wire run 45.

Figures 15 and 16 show the advance guide roll 110 used in conjunction with pick-up from the forming wire run 41 between the couch roll 24 and the forward drive roll 22, Figure 16 with its raised transfer roll axis 103 being preferable when possible, because of the wider gap 105 between the roll 22 and the upward run 26 of the transfer felt 25.

Figures 17 and 18 resemble Figures 15 and 16, but also have the gap 107 between the pick-up roll 34 and the transfer roll 20, bridged by the run 108 of the transfer wire 44. As with Figures 13 and 14, there is no direct nip at either pick-up or transfer. The auxiliary guide roll 59 controls the transfer wire run 45.

Whatl claim is:

l. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable pick-up medium brought into contact with the forming wire bythe pick-up roll, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, a press, an

endless bottom felt passing around the transfer roll and to the press, said pick-up roll being provided with a suction box, said pick-up medium and said felt beyond the diverging point having unsupported `lengthsy extending to and around auxiliary stretch rolls.

2. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless pick-up wire brought into contact with the forming wire by the pickup-roll, a suction transfer roll defining a nip with the pick-up roll on the side `of the pickup roll remote from the couch roll, an endless bottom transfer felt passing through the nip of the two rolls, said pick-up roll causing said pick-up medium to contact said forming wire and then pass into contact with the bottom felt on the transfer roll substantially immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the first point of contact of the pick-up medium with the forming wire to the first point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to Icause the pick-up kmedium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll.

3. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing -over the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable pick-up medium brought into contact with the forming wire by the pick-up roll, a suction transfer rollforming a nip with the pick-up roll on the side of the pick-up roll remote from the couchroll, a stretch roll for the pick-up medium, said pick-up roll being provided with a suction boxvextending substantially from the first point of contact` of the pick-up medium with the forming wire to the first point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around. part of the transfer roll substantially immediatelyron leavingthe pick-up roll 7 and then to diverge from the transfer felt when the web and the felt have left the transfer roll.

4. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll and an advance guide roll mounted adjacent to the couch roll but spaced from the forming wire at the couch roll, an endless pick-up medium passing around the guide roll and the pick-up roll and brought into contact with the forming wire between them, a suction transfer roll adjacent the pick-up roll on the side of the picloup roll remote from the couch roll, an endless bottom transfer felt passing around the transfer roll, said pick-up roll being provided with a suction box extending substantially from the rst point of contact of the pickup medium with the forming wire to the first point of contact of the piek-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pickup roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll.

5. A Fourdrinier paper-making machine comprising a couch roll, a forward roll, a forming wire passing over the couch roll and the forward roll, a suction pick-up roll, an endless pick-up medium brought by the pick-up roll into contact with the forming wire between the couch roll and the forward roll, a suction transfer roll defining a nip with the pick-up roll on the side of the pick-up roll remote from the couch roll, an endless bottom transfer felt passing around the transfer roll, said pick-up roll being provided with a suction box extending substantially from the first point of contact of the pick-up medium with the forming wire to the rst point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up mediurn to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll.

6. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll, an endless pick-up medium brought by the pick-up roll into contact with the forming wire, a suction transfer roll adjacent the pick-up roll, an endless bottom transfer felt passing around the transfer roll, said pick-11p roll being provided with a suction box extending substantially from the first point of contact of the pick-up medium with the forming wire to the rst point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll, and manually controlled means to swing the pick-up roll clear from the forming wire changing of the pick-up wire when a new pick-up wire is desired.

7. A Fourdrinier paper-making machine of the class described, comprising: a suction couch roll, a forming wire passing over part of the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable piek-up medium passing around part of the pick-up roll, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, and endless .bottom transfer felt passing around part of the transfer roll, a guide roll for said pick-up medium mounted -at a substantial distance from said transfer roll, said pick-up roll causing said pick-up medium to contact said forming wire `and then pass into contact with the bottom felt on the transfer roll substantially immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the rst point of contact of the pick-up medium with the forming wire -to the rst point of contact of the pick-up medium with the transfer felt on the transfer roll, the guide :roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll, and pivoted arms to carry the pick-up roll clear from the forming wire for changing of the pick-up wire when a new pick-up wire is required.

8. A Fourdrinier paper-making machine comprising: a suction couch roll, a forming wire passing over part of the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable pick-up medium passing around part of the pick-up roll, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, an endless bound transfer felt passing around part of the transfer roll, a guide roll for said pick-up medium mounted at a substantial distance from said transfer roll, said pick-up roll causing said pickup medium to contact said forming wire and then pass into contact with the bottom felt on the transfer roll substantially immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the first point of contact of the pick-up medium with the forming wire to the rst point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll, pivoted arms carrying the pick-up roll, means to swing the arms clear of the forming wire, beams carrying the guide rolls and the arms, removable pieces supporting the beams, and further beams for insertion in the machine to support the first beams on removal -of the pieces, thus permitting insertion of the endless pick-up medium after swinging of the pick-up roll in a position remote from the transfer roll.

9, A Fourdrinier paper-making machine of the type in which a suction pick-up roll having an endless permeable pick-up medium passing around the roll cooperates with a forming wire in the vicinity of the couch roll to remove the paper web, and a suction transfer roll disposed on the side of the pick-up roll remote from the couch roll having a bottom transfer felt passing over the transfer roll to receive the paper web from the pick-up medium and carry it to a press, comprising: a suction couch roll, a forming wire passing over part of the couch roll, a suction pickup roll mounted adjacent to the couch roll, an endless permeable pick-up medium passing around part of the pick-up roll, a suction transfer roll adjacent the pick-up roll ron the side of the pick-up roll remote from the couch roll, -an endless bottom transfer felt passing around part of the transfer roll, a guide roll for said pick-up medium mounted at a substantial distance from said transfer roll, said pick-up roll causing said pick-up medium to contact said forming wire and then pass into contact with the bottom felt on the transfer roll substantially immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the first point of contact of the pick-up medium with the forming wire to the first point of Contact ofthe pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll, the axis of the suction transfer roll being in substantially the same horizontal plane as the axis of the pick-up roll and on the side of the pick-up roll remote from the couch roll.

l0. A Fourdrinier paper-making machine comprising a suction couch roll, a forming wire passing over part of the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable pick-up medium passing around part of the pick-up roll, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, an endless bottom transfer felt passing -around part of the transfer roll, a guide roll for said pick-up medium mounted at a distance from said transfer roll, said pick-up roll causing said pick-up medium to contact said forming wire and then pass into contact with the bottom felt on the transfer roll immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the rst point of contact of the pick-up medium with the forming wire to the first point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll, pivoted arms to carry the pick-up roll, means to swing the arms to position the pick-up roll away from the transfer roll, and means to swing the arms to control the pressure at a nip formed by the pick-up roll and the transfer roll.

11. A Fourdrinier paper-making machine of the type in which a suction pick-up roll having an endless permeable pick-up medium passing around the roll cooperates with a forming wire in the vicinity of the couch roll to remove the paper web, and a suction transfer roll disposed on the side of the pick-up roll remote from the couch roll having a bottom transfer felt passing over the transfer roll to receive the paper web from the pick-up medium and carry it to a press, comprising: a suction couch roll, a forming wire passing'over part of the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless permeable pick-up medium passing around part of the pick-up roll, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, an endless bottom transfer felt passing around part of the transfer roll, a guide roll for said pick-up medium mounted at a distance from said transfer roll, said pick-up roll causing said pick-up medium to contact said forming wire and then pass into contact with the bottom felt on the transferv roll substantially immediately on leaving the pick-up roll, said pick-up roll being provided with a suction box extending substantially from the rst point of contact of the pick-up medium with the forming wire to the rst point of contact of the pick-up medium with the bottom transfer felt on the transfer roll, the guide roll being positioned to cause the pick-up medium to curve around part of the transfer roll substantially immediately on leaving the pick-up roll and then to diverge from the transfer felt when the web and the felt have left the transfer roll.

12. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll mounted adjacent to the couch roll, an endless pick-up medium brought into contact with the forming wire by the pick-up roll, a suction transfer roll disposed on the side of the pick-up roll remote from the couch roll and separated from the pick-up roll by a gap, an endless bottom transfer felt passing round the transfer roll, and guide means to cause the pick-up medium to bridge the gap between the pick-up roll and the transfer roll to form an arc over the felt on the transfer roll and then to diverge from the transfer felt.

13. A Fourdrinier paper-making machine comprising a couch roll, a forward roll, a forming wire passing over the couch roll and the forward roll, a suction pick-up roll and an advance guide roll mounted adjacent to the couch roll but both clear of the couch roll, an endless pick-up medium passing round the guide roll and the pick-up roll and brought into contact with the forming wire between them, a suction transfer roll adjacent the pick-up roll on the side of the pickup roll remote from 10 the couch roll, with a gap between the pickup roll and the transfer roll, and guide means to cause the transfer felt and the pick-up medium to diverge after the pick-up medium has bridged the gap to make contact with the transfer felt at the transfer roll.

14. A Fourdrinier paper-making machine comprising a couch roll, a forward roll, a forming wire passing over the couch roll and the forward roll, a suction pick-up roll and an advance guide roll mounted adjacent to the couch roll but both clear of the couch roll, an endless pick-up wire passing round the guide roll and the pickeup roll and brought into contact with the forming wire between them, a suction transfer roll adjacent thepick-up roll on the side of the pick-up roll remote from the couch roll, with a gap between the pick-up roll and the transfer roll, and guide means to cause the transfer felt and the pick-up wire to diverge after the pick-up wire has bridged the gap to make contact with the transfer felt at the transfer roll. I

15. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll, a guide roll in advance of the pickup roll, both rolls being spaced from the couch roll, an

endless permeable pick-up medium brought into contact with the forming Wire by the guide roll and the pick-up roll over an arc of the couch roll that is convex upwardly, to remove a paper web from the wire and carry it in an arcuate path convex downwardly, a suction transfer roll with its axis nearly at the height of the pick-up roll axis on the side of the pick-up roll remote from the couch roll, there being a gap between the transfer roll and the pick-up roll, an endless bottom transfer felt passing round the transfer roll, and guide means to cause the pick-up medium to bridge the gap between the pick-up roll and the transfer roll, so that the medium transfers the web to the transfer felt in an arc of reverse curvature, the pick-up medium and the transfer felt diverging when the felt has left the transfer roll with the web.

16. A Fourdrinier paper-making machine comprising a couch roll, a forming wire passing over the couch roll, a suction pick-up roll and an advance guide roll mounted adjacent to the couch roll but both spaced from the forming wire at the couch roll, an endless pick-up medium passing round the guide roll and the pick-np roll and brought into contact with the forming wire between them, a suction transfer roll adjacent the pick-up roll on the side of the pick-up roll remote from the couch roll, an endless bottom transfer felt passing round the transfer roll, and a further guide roll to cause the pick-up medium to curve round part of the transfer roll on leaving the pick-up roll and then to diverge from the transfer felt when the felt has left the transfer roll, said transfer roll being separated from the pick-up roll to provide a gap therebetween, and said pick-up medium bridging said gap as it passes from the pick-up roll to the transfer roll.

References Cited in the leof this patent UNITED' STATES PATENTS Goodwillie Nov. 16, 1954