US2890748A - Fiberboard apparatus - Google Patents

Description

June 16, 1959 K. HEINRICH FIBERBOARD APPARATUS F11 Aprill :5, i956 nited States Pate-nt 2,896,74` FIBERBOARD APPARATUS t LudwigI K. Heinrich, Chesterton, Ind., assigner to The Celotex Corporation,- Chicago, Ill., a corporation of Delaware Application pril 3, 19'56, Serial No. 575,857

5 Claims; (Cl. 162-358) The inventions hereof are with respect to the press section of a machine of the paper-making type.

,l The disclosed inventions are of particular value in connection with the manufacture of berboard products made on machines of the so-called paper-making machines. Essentially machines on which paper and berboard are made are of the same general construction, each, however, suitably modified as to details and speciiic construction for production of felted sheets of the respective thickness.

The press section of the paper-making type apparatus is a portion of the over-all apparatus positioned between the sheet-forming section and the drying section. The function of the press section is that of further reducing the moisture content of the felted sheet, as compared with its moisture content as issuing from the felting section, so that the wet sheet may be delivered to the drying section with as low moisture content as can be obtained through the application of mechanical forces. The press section normally comprises basically a pair or pairs of squeeze rolls with top and bottom endless belts arranged to receive the wet sheet between them and between which the sheet is carried through the squeeze rolls. Normally the wet sheet, after it has been felted and has drained, passes between a pair or several pairs of squeeze rolls which, however, can exert but very light squeeze action to further reduce the water content of the sheet, since any appreciable pressure so exerted on the wet sheet would destroy the felted structure thereof. After the water in the wet sheet has been reduced as much as possible by drainage and the relatively light squeezing action to which it is subjected, in the sheet-forming section it is suiiiciently consolidated so that it may be subjected to relatively drastic squeezing to further reduce the water content provided that during such relatively drastic squeezing the sheet is suitably supported and conveyed, as on drier felts, as particularly shown and described hereinafter.

' Normally the press section of the paper-making type machine comprises a pair of squeeze rolls, one mounted above the other, with provision for exerting relatively heavy pressure on the upper roll so as to squeeze the wet sheet between the rolls as it passes therethrough. To carry the wet sheet through the squeeze rolls and to Patented June 16, 1959 The inventions hereof relate particularly to an improvement which may be referred to as a modification of .the bottom felt arrangement of the press section, It is believed that it will be obvious that as a wetfelted sheet is carried into the nip of the press rolls between the top and bottom felts, that due to the squeezingaction of the press rolls, the water squeezed fronrthe sheet is continuously forced backward away from the point at which the press rolls are exerting pressure' to squeeze the water from the wet s heet. This normally results in the building up, more or less, of a pond behind the press rolls which tends to weaken the already weak sheet and to some extent probably acts as a reservoir from which Water tends to be drawn back into the sheet as the squeezing pressure is released when the sheet issues from the further side of the squeeze rolls.

The inventions hereof deal particularly with a modication of the normal construction with a view of providing means whereby at least a portion of the excess water as it is squeezed from the sheet by the squeeze rolls may escape from the sheet and the felts so that there is q much less tendency to build up a pond behind the squeeze some of the excess water as it is squeezed from the Wet sheet and for carrying such excess water away and comprises a type of endless link belt which is installed to encompass a portion of the periphery of the lower press roll and is interposed between the periphery of the press roll and the lower felt. This endless link belt is not solid, that is, spaces are provided therein which constitute reservoirs into which water may be squeezed from the wet sheet and felts, which water will then, as the rolls rotate, be carried away from the nip of the rolls and be harmlessly discharged. Should such endless chain belt not provide suicient capacity for carrying away all the water squeezed from the wet sheet by the squeeze rolls, so that there is a tendency for some reservoir of water to be built up behind the press rolls, there is further provided a pair of boxes positioned closely pressure source and the other to a gaseous suction source.

preserve its integrity as a sheet, there are ordinarily provided, in connection with each of the squeeze rolls, an endless felt with the felts so arranged that the lower comprises a horizontal conveyor to receive the wet sheet and carry it through the squeeze rolls, and in conjunction with the upper squeeze roll a second endless felt, a portion of which runs substantially parallel to the lower felt but at a slight angle so that such runs of the felts converge toward the squeeze rolls. With such construction it is evident that while the sheet is carreid to the squeeze rolls primarily on the lower felt, as the sheet approaches the squeeze rolls the upper felt, due to its inclination, will contact the upper surface of the sheet so that as the sheet passes into the squeeze rolls it is conveyed therethrough between the top and bottom felts.

The upper box is connected to a pressure source and the lower to a suction source, and it will be obvious that the gaseous pressure from the upper box will tend to force any free water away from the upper felt and through the sheet into the lower felt, and that the lower suction box will tend to draw any such free water from the lower belt and carry it away so that a reservoir of free water cannot build up behind the rolls.

The principal object of the inventions hereof is the provision of new and novel means providing, particularly, in connection with the manufacture of ber insulation board a means in the press section of the sheet-producing apparatus for reducing the moisture thereof below that normally obtained by the conventional press section. A further object of the invention is that of providing in such a press section, means for receiving excess water as it is squeezed from the sheet to carry such excess water away and discharge it. Specifically, an objective of the invention is to accomplish the general objectives as just previously referred to by providing reservoirs or recesses to receive excess water as it is squeezed from the sheet so that such may be carried away and discharged. Additionally it is an objective to provide means for positively removing water which may be squeezed backwards along 3 the sheet and which would otherwise form a reservoir of water rearwardly of the squeeze rolls. Other and further objectives will become apparent upon reading the following description of the apparatus setting out the functioning of the apparatus as illustrated in the accompanying drawings.

The construction generally described above is illustrated in the accompanying drawings, in which Fig. 1 is a diagrammatic illustration of the press section lof a papermaking type machine;

Fig. 2 is a top plan view of a small part of the endless link chain belt;

Fig. 3 is a side elevation of such portion of the chain link belt;

Fig. 4 is a view similar to Fig. 2 but of a modied type link; and

Fig. 5 is a side elevation ofthe modilied form of link chain belt.

In the accompanying drawings the press section of a paper-making type machine is diagrammatical'ly illustrated in Fig. l. Such press section comprises a pair of squeeze rolls and 11, one mounted above the other on horizontal and parallel axes, the respective shafts being designated by numerals 12 and 13. It is to 'be understood, of course, that the shafts 12 and 13 of the squeeze rolls are to be suitably journaled, and that provision is made for applying relatively heavy pressure to either one or the other of such squeeze roll so that such pair of rolls will be eiective to squeeze excess water carried by a fe'lted sheet passing therethrough. Such is conventional as is also the case with respect to the various felt-carrying rolls and so on which, as has been stated, are shown merely in diagrammatic form illustrative of a normally conventional press section construction.

Associated with each of the press rolls there are provided endless felts which are suitably arranged to carry the wet felted sheet into and through the squeeze rolls 10 and 11. Felt 15 is associated with squeeze roll `10, and felt 16 is associated with squeeze roll 11. Felt 15 is arranged so that .it runs substantially horizontally but, however, inclined downwardly toward roll 10 to a slight degree and then upwardly and around various carrier rolls 17 and take-up roll 18 and endlessly back to the periphery of roll 1.0.

Endless felt 16 is arranged Vso that a portion runs substantially horizontal, then over a portion of the periphery of lower squeeze roll 11 and then downwardly and around .carrier rolls 19 and take-up roll 20 .to again enter its horizontal run to the periphery o'fsqueeze roll 11.

An endless link chain belt 25 'is provided to encircle lower squeeze roll 11 interposed between the periphery thereof and the lower side of felt 16, which chain l.link belt passes around ro'll 26 and in .connection with which shower -27 may be provided for washing out of the link chain belt any fiber or dirt which may have accumulated between the links. Pan or tray 28 is provided Aunder chain link belt 25 to receive water discharged therefrom, the pan 28 being provided with any suitable discharge.

Rolls 29 are merely diagrammatic representation .of the nal pair of rolls on the paper machine and are shown merely to indicate that there is Ipreceding equipment from which the sheet feeds to the press section.

Pressure box 23 and suction box ,24 positioned immediately behind press rolls l0 Vand 11 are, respectively, connected to pressure and suction sources..

The drainage belt, .the :endless chain link belt 25, is preferably .comprised .of links which .are quite similar to silent chain links but modified for the particular use. The preferred form .of link is rthat .of Fig. 2 where .links 30 are, as stated, .the .same ,as silent chain links .except that their end portions, .below the .openings which receive pivot pins 31, are not beveled `but .are .continued ,straight downwardly to provide .dat bottom :lug portions v33. Such 4links when formed into a .chain .by .being mounted on pivot pins 31 will, it is readily evident, provide a large number of openings between adjacent links for receiving water squeezed from the sheet felts as they are squeezed in the nip of press rolls 11 and 12. The form of link which has been described provides not only spaces between links for receiving expressed water, -but it will be seen that lugs 33 hold the body of the link spaced away from the surface of the roll on which the chain is operating and thus there is provided a 1reservoir 34 in which the expressed water may collect and be removed from the sphere of the pressing action.

There is also illustrated an alternative link chain construction |which may be used but which is not considered to be quite as satisfactory as that previously described, at least in some particular uses. The modilied form of link, as illustrated in Figs. 4 and 5, is a silent chain link slightly modified. Here the link 30 has end portions which are the same as the form of ordinary silent link chains but the body or connecting portion 0f the link is modiied slightly 'in that the lower surface is ground or formed to the radius of curvature of Athe roll on which the .chain is t0 run in order that the chain will hug the ro'll ,on which it is mounted.

'When a chain such as that described is used, suitable V-grooves such as v37 are c ut or provided Vin the surface of the roll, and it will be understood that the V-shaped end portions 36 of the links will register in such vgrooves as the roll revolves. A chain made up of such links as just described lby mounting on pins 31 it will, it is seen, provide recesses or openings between adjacent links to receive water expressed by the press roll and to carry such away from the pressing area for discharge.

it is believed that it will be understood that the preferred belt construction for removing the water from the area of the pressing action is that described in connection with the illustrations of Figs. 2 and '3. A chain of such construction provides a much greater volume for receiving .expressed water so that even if considerable water is expressed, it fis substantially impossible that the spaces between the links may fill up with water, whereby it might be drawn back into the felt as the felt leaves the pressing area.

It is preferable that the links 30 of the chain construction, provided for receiving excess moisture which is expressed, shall be relatively narrow, and it is suggested that for most applications that the `links should he `9&6 inch in width. B y having the .chain made up of relatively narrow links the sheet being pressed and, `of course, .the felt on which it is being carried .through the press rolls are well supported and there is no possibility that ysuch might be pressed down into the space .between adjacent links.

It is believed that the operation and effectiveness of the apparatus disclosed and described is ful-ly evident to anyone skilled in the art t0 which the invention pertains. However, to sum up the functioning and operation of the apparatus, such provides for carrying away excess water pressed out of a iber sheet which is carried between top and bottom felts and squeezed between press or squeeze rolls ofthe press section of a paper-making .'CYPe machine, By providing means for .getting .excess water away from the area of pressing, such prevents `a `reservoir of .water being .built .up `behind .the press rolls, which fis disadvantageous since such .a reservoir vof water provides a source from which `the expansion -of the sheet as ,it is released from .the pressing pressure rtends to suck-or draw water backinto the sheet from such :reservoir :of Water, By providing a -chai-n or the like under :the :bottom felt, which chain is vof construction such that it has openings or recesses into which excess water as it is pressed out may escape and lbe carried away from the area 0f pressin g, it -is obvious that the possibility of building -up -a reservoir-of water behind the rolls 41is completely .or largely overcome. In connection with Vthe described construction, it is also evident that if the chain link belt, as .d escribed, does not have sulcient capacity to carry away all the excess water expressed from the sheet being pressed, so that there is a tendency for a reservoir of water to be built up behind the press rolls, the combination pressure and suction boxes provided constitute means for carrying away such excess water. Also the combination pressure and suction boxes referred to will generally remove a portion of the Water content from the fiber sheet just before it passes to the press rolls, and thus the sheet as it passes into the area of pressing will contain somewhat less water than would be contained therein were such combination pressure and suction boxes not included in the construction.

The inventions hereof having been disclosed and described in detail, I claim:

l. In combination in a press of the paper-making machine type comprising spaced coacting press rolls and endless press conveyors, one associated with each of the press rolls and partially encompassing the periphery thereof and conveying therethrough a sheet to be pressed; a third endless conveyor having a portion thereof operatively positioned between the periphery of the lower press roll and the press conveyor associated therewith, the endless conveyor, positioned between the periphery of the lower press roll and its associated press conveyor associated therewith, having openings extending through the thickness thereof.

2. In the combination of claim l, the openings extending through the thickness of the endless conveyor positioned between the periphery of the lower press roll and its associated press conveyor, comprising the spaces existing between adjacent links of a link chain belt.

3. In the combination of claim l the links of the link chain belt comprised of links having narrow elongated body portions perforated adjacent their ends and receiving connecting pins, and extending downwardly beyond the perforations, lug portions spacing the body portions from the periphery of the press roll with which the link chain belt is associated.

4. In the combination of claim 1, the openings extending through the thickness of the endless conveyor positioned between the periphery of the lower press roll and its associated press conveyor, comprising the spaces existing between adjacent links of a link chain belt, the link chain belt comprised of narrow elongated links formed with elongated body portions perforated adjacent their ends and receiving connecting pins, and extending downwardly beyond the perforations substantially V-shaped portions, the surface of the cooperating press roll having complementing V grooves therein receiving the V-form portions of the links of the link chain belt.

5. In combination in a press of the paper-making machine type comprising spaced coacting press rolls and endless press conveyors, one associated with each of the press rolls and partially encompassing the periphery thereof and conveying therethrough a sheet to be pressed; a third perforated endless conveyor, the perforations extending through its thickness, having a portion thereof operatively positioned between the periphery of the lower press roll and the press conveyor associated therewith, a pressure box, positioned above the lower run of the conveyor associated with the top press roll, closely adjacent the top press roll and with the conveyor comprising a lower face therefor and a substantially co-extensive suction box, positioned below the upper run of the conveyor associated with the bottom press roll, positioned closely adjacent the bottom press roll and with the conveyor comprising the upper face thereof.

References Cited in the file of this patent UNITED STATES PATENTS 611,422 Savery Sept. 27, 1898 1,153,103 Neale Sept. 7, 1915 1,539,339 Wagner May 26, 1925 2,027,657 Van Roggen Jan. 14, 1936 2,783,689 Skoldkvist Mar. 5, 1957

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