US 1163252 A
Description (OCR text may contain errors)
W. H. MILLSPAUGH.
APPLICATION FILED 0m. 7, 1909.
Patented Dec. 7, 1915.
2 SHEETS-SHEET 1- wifnzoaea W. H. MILLSPAUGH.
APPLICATION FILED OCT. 7. 1909.
Patented Dec. 7, 1915.
2 SHEETS-SHEET 2.
WITNESSES w m Av D s'rATEs v T FFICE.
To all whom it may concern: I
Be it known that I, WILLIAM H. Mums- PAUGH, a citizen of the United States residing at Sandusky, in the county of llrie and State of Ohio, have invented certain new and useful Improvements in Paper- Making; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.
This invention relates to the art of papermaking, and provides a new method of and means for producing paper or drying same in manufacture without expressing or squeezing out water by mechanical compression.
In my invention the paper is dried in acontinuous web (preparatory to passing same over drying cylinders or other finishing driers), by first abstracting moisture from and drawing large quantities of air through the sheet by vacuum, then exposing the sheet for a considerable extent to contact with heated air, and then drawing heated air, through the sheet, though this last mentioned step may be omitted; after which the sheet is preferably passed through press rolls and thence to the driers or taken directly to the driers as desired. This results in eiiicient and rapid drying, the sheet being thereby delivered to the presses and driers at a much higher percentage of dryness than is possible with former methods, and in better condition for steam drying with best results; thus also facilitating the drying operation and increasing the speed and capacity of the machine to which my invention is applied; production being also increased by elimination of frequent sources of breaks in the wet web at the couch rolls and presses; and I also produce a better grade or quality of paper, uniformly dried and of smoother finish, free from Wire marks and felt marks, hence of uniform smoothness on both sides, and without other imperfections which frequently arise in the present practice of the art of paper making,
as more fully set forth in my application for an improved method of paper-making, filed October 7, 1909, Serial No. 521,536.
The apparatus of my invention also offers eflicient means for application of size, color, water proofing or parchmentizing, and for conducting other treatments of the paper Specification of Letters Patent.
Patented Dec. 7, 1915.
Application filed October 7, 1909. Serial No. 521,537.
sgch as special sizing, loft drying effects, e c.
to -.be taken as a part of this specification, Figure represents diagrammatically a paper-making machine of the Fourdrinier type embodying my invention, and by which my improved method may be carried out. This View illustrates so much of the machine as precedes the driers. Fig.2 is an enlarged sectional view of the principal part of the invention.
1 indicates the making-wire which passes over a breast roll 1 and over a suction-roll 2 (located in place of the-usual lower couch roll) and over an intermediate series of table rolls supporting the upper run of the wire as usual in such machines; the lower run of the wire passing over suitable guiding and tensioning rolls as usual. Deckel straps 1 running over pulleys 1 are arranged above the making-wire as usual.
1 is a dandy roll and l a guide roll,
The foregoing parts are or may be substantially as in any ordinary Fourdrinier machine, except that the couch rolls and other accessories are eliminated, the suction roll 2 being substituted therefor and taking the place of the usual couch roll, and I also eliminate all or part of the usual equipment of flat suction-boxes, all of such boxes being preferably discarded except that one (1) required to remove water for dandy roll purposes, if the dandy roll 1 is retained, or to hold the edges of heavy or slow sheets between the deckels and the suction-roll 2 on such machines as may not be equipped with deckel straps extending down to the suction-roll.
Adjacent to the suction-roll 2 is a suctionroll 3, and at a distance behind the same is a suction-roll 4. Around them runs an endless porous or perforated web carrier, preferably a wire cloth .or common Fourdrinier wire 5, similar to the making-wire 1. The lower run of this second Wire 5 passes over suitable guiding and tensioning rolls as indicated.
As understood, the suction-rolls comprise revolving foraminous' or perforated shells or cylinders having suction-chambers or suction-boxes therein, indicated at 2, 3 4, in communication with a vacuum pump or pumps. The suction-boxes should be provided withadjustable packing heads for ad- In the accompanying drawings, which are justing purposes in accordance with differ;
this purpose I preferably employ in connec-' tion with the suction-boxes high power positive rotary vacuum pumps (not shown), as described in my pending application for patent for an improvement in paper-making machines, filed October 7, 1909, Serial No. 521,535 and in view of the heavy vacuum maintained I preferably employ suctionrolls having provision for maintaining airtight contact between the suction-box or boxes and inner surface of the revolving shell or cylinder and for limiting the pressure of such contact to prevent the suctionbox or boxes from becoming locked to the shell or cylinder under influence of vacuum, with consequent wear, chatter and increased driving power; whereby I am enabled to operate the suction-rolls safely while maintaining such heavy and uniform vacuum as necessary to pass the desired large and uniform quantities of airthrough the sheet of paper and to cause the external air pressure upon the sheet to lock the making-wire 1 to the suction-roll 2, so that the means which rotate the latter may also be utilized for driving the making wire. In the same manner the second wire 5 may be driven by the rolls 3 and 4. I prefer a construction of suction-roll substantially as shown and described in my U. S. Patent No. 895,281, dated August 4, 1908, though I do not limit myself thereto.
Under the wire 5, between the suctionrolls 3 and 4, is an air tight box or chamber 6, having adjustable sides, into which hot air is supplied by a pipe or pipes 6 at the dry end of the box, that is at the end farthest from the wet end of the machine, while at its opposite or cold end the box is or may be provided with an adjustable hinged gate or valve 6", to permit discharge of the hot air after it has acted upon the paper passing over the box. Deckel straps 6 may run on the top of the'sheet on this second wire to hold the edges of the sheet from lifting from the wire under the action of the hot air, or a second endless wire may be arranged to lie flat upon the sheet of paper and hold it down.
The suction-roll 4 is provided with a hood 7 for hot air, opposite the suction-box 4*, hot air being supplied to said hood through a pipe or pipes 7 from a suitable heater, or the air being heated in the hood by steam pipes or other suitable means. In operation, the layer of pulp which has formed on the making-wire 1- passes on the the sheet being moreover uniformly and thoroughly treated, due to the uniform pressure upon and draft of air through th sheet; while at the same time the air pressure upon the outer side of the sheet locks the making-wire to the roll which is thereby enabled to drive the wire accurately and effectively, doing away with supplemental driving means.
By the treatment to which the sheet is subjected on suction-roll 2, the sheet ac qulres such integrity and becomes sufficiently dry to enable it to be taken the more easily and safely from the wire, and in this connection a slotted or perforated pipe 2 may be introduced into the suction-roll and used for etting air or steam for blowing ofi the sheet at the proper point, doing away with picking OK the sheet by hand; the air delivered from said pipe passing through the apertures or perforations in the roll and striking the inner side of the paper. The same device may be applied at the proper point to the roll 4, as indicated at 4", for blowing off the sheet for delivery to the press felt.
From the suction-roll 2 the sheet is taken on the wire 5 which carries same first over the suction-roll 3, then over the hot air box 6, and then over the suction-roll 4. Atmospheric air is drawn through the sheet in passing over the suction-roll 3, thus further advancing the drying operation by the passing of large quantities of air uniformly through the sheet, and without any squeezing or rolling, so that the fibers are not subjected to mechanical compression at this time; and in passing over the box 6 the hot air strikes the under side of the sheet of paper lying on the wire, the advancing sheet being subjected to contact with such hot air for a prolongedperiod (depending upon the length of the box), and at a gradually increasing temperature due to the arrangement of the hot air supply pipes 6 and in passing over the suction-roll 4 and under the hood 7 hot air is applied to the opposite side of the sheet and drawn through the sheet by the vacuum in the suction-roll, absorbing remaining moisture.
By this method the sheet is thoroughly and uniformly treated in a highly efiicient and economical manner, avoiding the exactions of uniform pressing and overcoming the well known difliculties of uniform drymesses ing, and avoiding the impression of wire marks and felt marks due to the usual squeezing of the web or sheet on the making-wire between couch rolls and compression of the damp sheet on felts between press rolls, besides which the sheet is delivered to the presses much drier and tougher than it is possible to make it with the present known methods of paper-making.
It is well known in the industry that ordinary drying cylinders are not efficient as a means for transferring heat to a sheet of paper and drying the same, as not more than forty-five to fifty per cent. of the surfaces of said drying cylinders are actually in contact with the paper, the balance radiating heat into the atmosphere; whereas with the method herein set forth all the heat or the major portion of the heat is carried through the paper, absorbing moisture and resulting in great economies in the use of the same.
After passing from the suction-rolls, the sheet of paper is preferably carried through 'press-rolls for pressing and smoothing same preparatory to going over the drying cylinders; and as shown in Fig. 1 the sheet is taken from the suction-roll 4 upon a press felt 8 through first press rolls 9 and thence carried bare through second and third press rolls 10 and 11, the sheet being ordinarily in such condition that the use of felts for carrying same through the second and third presses may be dispensed with; and on certain grades of paper, owing to the compactness and integrity of the web or sheet resultin from the before described treatment, the feits may be altogether omitted and the web or sheet run bare through the first and remaining presses, not needing the assistance of felts or tapes. Web guiding and tensioning rollers may be arranged between the presses as shown. In some cases the presses may be entirely eliminated and the sheet taken direct to the driers.
In connection with the press felt, I have provided an improved means for continuous washing and drying of'the same. The felt 8, after passing between the wellknown shower pipes 8 for cleansing and rubbercovered squeeze rolls 8 for wringing or squeezing, passes over a suction-roll 8 for drying the felt and keeping same open before the sheet of paper meets the same, and then over a suction-roll 8 to flatten the sheet of paper down on the felt and draw the air out from between the paper and the felt so that the paper will not blow at the press rolls. The fimctions of the two small suction-rolls 8 and 8 could be performed by one large suction-roll having two suctionboxes at different points, one to operate on the felt before the paper meets the same and the other to hold the sheet to the felt.
It is obvious that different treatments may be required or desirable for different grades of paper; thus in some cases heated air may be applied at the suction-roll 3, the latter being hooded for this purpose, if the nature additional suctionrolls may be arranged for taking the paper beyond the suction-roll 4c, and such rolls may similarly be hooded for hot air, and the process of drawing hot air through the paper may be continued until the point is reached in the process of manufacture where it is not desirable, economical or efficient to continue the drying in this manner, after which the paper will be passed through the presses and to the driers or directly over drying cylinders or other drying means in the usual manner.
By-the process herein set forth, it is entirely possible and practicable to produce a sheet of paper drier before going over the drying cylinders than after it has passed through fifty per cent.- or more of the drying-cylinders of an ordinary Fourdrinier machine of large drying capacity; by which it will be seen that the capacity of the driers may be enormously increased, or a shorter equipment of drying section may be employed; and by continuing the process outlined it may be practicable to completely dry the paper in this manner and dispense with the use of drying cylinders except such as may be needed for smoothing, ironing or calendering the paper.
The foregoing ofi'ers a practical solution of the problems of papernnaking and drying, and by this system it will be practicable on many papers to run machines without the use of felts and with half or less than half of the driers now used.
Substances for sizing, coloring, waterproofing or parchmentizing may be applied as a spray or with rolls, baths or other well known methods, to the sheet at or adjacent to one or more of the suctionrol1s, being drawn into and caused to thoroughly permeate the sheet by reason of the uniform suction; and the sheet may also be watermarked by the use of cylinders or rolls covered with type of metal or other substance, or by the use of well constructed dandyrolls, operating on the sheet preferably at or near the suction-roll 2. On the wire 5 chemical treatments for special sizing or other purposes may be conducted at will,
and for loft drying effects the section of the machine comprised between and including the suction-rolls 3 and a may be used independently. This section of the machine is also adapted and can be applied to present types of paper-making machines with materially advantageous results in improving the quality of the product and capacity of such machine.
Having thus described my invention, what I claim is: j
1. The process of drying paper in a continuous web, in the manufacture thereof from pulp, which consists in substantially abstracting its expressible moisture from and drawing air through the sheet by vacuum and then passing the sheet in contact with heated air.
2. The process of drying paper in a continuous web, in the manufacture thereof from pulp, which consists in drawing moisture from and air through the sheet by vacuum, then subjecting the sheet to contact with heated air, and then drawing heated air through the sheet.
3. The improvement in the art of making paper in a continuous web which consists in extracting its moisture without mechanical compression, by forcing large volumes of air uniformly through the sheet, and then pass ing the sheet in contact with heated air.
4. In a paper-making machine, the combination with a making wire, of an endless wire or porous carrier beyond the making wire, a hot air chamber over which said car rier passes, and vacuum chambers at opposite ends of said hot air chamber.
5. The combination of a plurality of suction-rolls adapted to operate on the web or sheet at successive points, a hot air supplier intermediate the rolls, and means for directing the web or sheet past the supplier in passing from one roll to the other.
6. The combination of a plurality of suction-rolls adapted to operate on the web or sheet at successive points, a hot air supplier intermediate the rolls, and means for carrying the web past the supplier from one roll to the other.
7. The combination of a making-wire, a suction-roll at the discharge end of the wire, suction devices beyond the wire, a hot air supplier adjacent the suction devices, and means for carrying the web or sheet past the supplier from one suction device to another.
,8. The combination of a pair of suction rolls, with an endless web carrier running messes over said rolls, a hot air supplier intermediate the rolls and adjacent theweb on said carrier, and a hot air hood beside one of the rolls.
9. The combination of a pair of separated suctlon-rolls, with a hot air box interposed between the suction-rolls, an endless web carrier running over both rolls and over said hot air box, and means for applying heated air at one or more of the suction-rolls.
10. The combination of a making-wire, a suction-roll at the discharge end of the making-wire, and a pair of suction-rolls beyond the wire, with an endless web carrier running over said pair of rolls, a hot air supplier arranged between said rolls and adj acent the web on said carrier, and a hot air hood over one of the suction-rolls.
11. In a paper-making machine, the combination of press rolls, a press felt, means for washing the felt, squeeze rolls for extracting water from the felt, a suction-roll interposed between the squeeze roll and press rolls for drying the felt, and a second suction-roll for holding the web on the felt adjacent the press rolls.
12. In a paper-making machine, the combination with paper web forming and drying devices, press rolls, a press felt for carrying the paper to the press rolls, and washing devices for the felt, of a suction-roll for gulding the felt and drying the same.
13. In a paper-making machine, the combination with paper web forming and drying devices, and press rolls, of a press felt for carrying the paper to the press rolls, guides for the felt, felt washing devices, and rolls for squeezing the felts, a suction-roll for guiding the felt and drying the same located adjacent the web drying devices, and a second suction-roll for holding the web on the felt adjacent the press rolls.
14:. The herein described method of making paper, which consists in subjecting a continuous web or sheet as it passes over the making-wire to the action of a heavy uniform vacuum, thereby drawing large volumes of air uniformly through the sheet, and then subjecting the sheet to heated air.
In testimony whereof I afiix my signature, in presence of two witnesses.
WILLIAM H. MILLSPAUGH.
C. L. MIELKE, SIDNEY FRoHMAN.