US 1438511 A
Description (OCR text may contain errors)
G. S. WITHAVI, 1R.
PAPER MAKlNG MACHINE.
APPLICATION FILED MAR. 24. I92I.
'Patented Deo. 112, 1922.
3 SHEETS-SHEET I.
351g @MQ/ammi# l PWM; M www; f www@ G. S. WITHAIVI, 1R.
PAPER MAKING MACHINE.
APPLICATION HLED MAR.24,1921.
Patented Dec. 12, 1922 3 SHEETS-SHEE`I 2.
' G. S. WITHAIVI, 1R.
PAPER MAKING MACHINE.
APPLICATION FILED MAR. 24,1921. 1&43895@ l Patented Dec. l2, 1922.
3 SHEETSMSHEET 3.
L# .A zg'afej//Zmm'jf 533% @143130144913 PWM; M www; r @A Patented Dec. 12, 1922.
GEORQ-E STANFORD WITHAM, JR., 0F HUDSON FALLS, NEW YORK.
Application led March 24, 1921. Serial No. 455,348.
To ,all whom 'it may' concern:
Be it knownthat I GEORGE S. WrrHAM, J r. a citizen of the Uznited States, reslding at l-Iudson Falls, in the county of Washing- :exact description of the invention, such as will enable others skilled in the art to which it lafpertains to make and use the same.
y invention is an improvement in paper maklng machines, and relates to mechanism for use in connection with such machines, for more perfectly and uniformly drying the web during its passage from the forming -mechanism to the calender rolls.
n the drying of paper by the usual methods, the web is drawn over a series of heated cylinders. in such a manner that the opposite faces of the formed web are alternately in contact with the heated peripheries of the cylinders and with the drying felts. With such arrangements, the opposite faces of the web are alternately subjected to high temperature and dry atmosphere and to low temperatureand moist atmosphere. When in contact with the cylinders, there is a rapid vaporization of the moisture on the one face, and a condensation. on the opposite face. Thus the web as a whole is alternately dried and moistened, with abrupt and relatively wide 'variations in temperature, ranging from extreme high to relatively low, condi tions which obviously do not conduce to the best results. y
The object of the present invention is to provide mechanism for use with paper making machines of the Fourdrinier type for removing from the web a large proportion of the moisture, before the web reaches the drying cylinders, and to subject both faces of the web throughout its travel past the drying cylinders, to a substantially uniform temperature, and to remove the vapor to prevent its condensation on the web, to insure uniform drying at a relatively low temperature.
is shown in connection with a F ourdrinier paper making machine of usual construction. Wlth the usual machine, the formed web 2 after it passes from between the statlonary rail, and the deckel strap, passes beneath the dandy roll 3 over the suction boxes indicated at 4. Afterwards the web passes over the stretch roll 5 and the couch lroll 6 and a dryer roll 7 which I substitute for the usual felt roll, to and between the upper and lower press rolls 8 and 9. From the press rolls 8 and 9, the web then passes between other similar press rolls, eventually reaching the press rolls 10 and 11 which are the last rolls, before the web passes to the dryer.
At points adjacent to the dandy roll, the stretch roll, the couch roll and each pair of press rolls, I arrange mechanism for directing upon the upper face of the formed web a blast of air, preferably hot air, and I substitute for, the usual couch roll, a suction roll indicated at 6, and for the usual felt roll a dryer roll indicated at 7. Above the 'paper making machine, and extending from the dandy roll 3 to near the dryer I arrange a conduit 12, which has depending branches 1.3,-14, 15 and 16, extending to near the dandy roll, the stretch roll, the couch roll, and the press rolls, a branch 16 being provided for each series of press rolls. The lower end of each branch 13, 14, 15 and 16 has a transversely extending nozzle 17, which is provided with suitable openings, for directing blasts of air onto the formed web 2. A baile 18 is arranged in front of the discharge of each nozzle, in a position to direct the blasts obliquely, onto the upper face of the web, in the direction in whichv the web is moving. The lnozzle of the branch 13 is above the dandy roll,` and the blasts impinge also upon the peripheral surface of the dandy roll, as well as upon that section of the formed web which is passing over the suction boxes 4. The nozzle of the 100 branch 14 is on the opposite side of the web from the stretch roll, as are also the nozzles of the branches 15 and 16. The nozzles of the branches 16 are so arranged that the air blasts will impinge upon the formed web just before the web passes into the nip of the rolls 8-9, or 10-11, as the case may be. Beneath each of the lower press rolls 9 and 11, I arrange a trough or save-all 19, through which is adapted to be circulated Figures 1, 2 and 3 are complementary diagrammatic views of a" portion of a Fourdrinier paper making machine provided with the improve paper drying mechanism. 'y AThe present embodiment of the invention hot water, by means of supply and discharge pipes 20 and 21. rIhe nozzles of those branches 16 adjacent to each pair ofpress rolls are similarly arranged, and each pair of press rolls has the save-all 19 below the lower roll. By means of these save-alls, the lower press roll of each set is heated, and assists in drying the web. The lower press rolls rotate in the hot water, and are heated thereby. After leaving the last series of press rolls, the web is temporarily inverted, and at such point I arrange a series or battery of three nozzles 22, each having a baille 23 for directing the blasts onto the face of the web obliquely, and in the same direction as the web is moving. Just before the web passes to the dryer, I arrange batteries of four nozzles each, one battery being arranged above the web and the other below. Each of the nozzles25 of the lower battery has the 'bailes 27 for directing the blasts obliquely onto the under face of the web, and in the direction of movement of the web. The upper battery may also be provided with baffles if desired.
In the usual form of dryer, consisting of heated cylinders 28 and 29, the cylinders are arranged in series, the series of cylinders 28 being at a higher level than the series 29,
and alternating with the members of series' 29. 'llhe web 2 is passed beneath a cylinder of series 29 above a cylinder of series 28, and in this manner from the Wet end of the dryer to the dry end. Thus each face of the web is alternately exposed to a relatively high temperature, and to a relatively low temperature, and at the same time is alternately exposed to a very dry atmosphere, and to a 4very moist atmosphere. As for instance when the web is passing beneath the first cylinder of series 29, the upper face of the web is subjected to the temperature of the highly heated cylinder, while the under face is .exposed to the relatively cool atmosphere. The moisture in the web is vaporized, and this vapor lies in contact with the lower face of the web, condensing on the same, and further cooling the web. The web as a whole in its passage through the dryer is ,constantly subjected to very high and 'relatively low temperatures, that is it is alternately subjected to an intense drying action, kand to a wetting action. Ubviously the web cannot be properly dried under such conditions.
In order to equalize the temperature on both faces ofthe web, and to remove the vapor from that face of the web which is remote from the heated cylinder, I arrange nozzles 30, 31, 32, 33 and 3% at di'erent points `in the dryer. The nozzle 30 for instance is arranged adjacent to the descendin portion of the upper drying felt 35, and d1- rects a blast of air onto the felt just before it engages the web on the rst cylinder of the series 28. The nozzles 31 are arranged above more efliciently, v
1ts Water more readily both at this point and 0 insegni and in rear of the nozzles 30, and bales 36 are arranged adjacent to these nozzles 31 for directing the blast of air onto the horizontal portion of the drying felt. rIhe nozzles 32 are arranged between the cylinders of the series 29, and the blasts of air from these nozzles are directed toward the under face of the lower drying felt 37 asit moves between adjacent cylinders of series 29. The nozzles 33 are arranged adjacent to the cylinders of series 29, in position to direct a blast of air onto the web, as it passes from a cylinder of series 29, to a cylinder of series 28, and the nozzles 34 are arranged above the lower run of the upperdrying felt, as it passes between adjacenty cylinders of series 28. All of these nozzles 30, 31, 32, 33, and 34, are supplied with air from a header 38 vwhich extends above the dryer, and with which the pipe 12 is connected. Another header 39 is arranged below the cylinders ofthe dryer, and below the lower dryin felt 37. This header has branches 40 whlch direct blasts against the web enaging face ofthe lower drying felt 37.
aiies 41 and 42 are arranged adjacent to these nozzles, for properly directing the blasts obliquelyv against the drying felt. These nozzles 3 1 to 34, inclusive, and nozzles IO thoroughly dry the drying felts, being directed against both faces thereof, and they remove the vapors which are generated by the heat of the drying cylinders, so that vsuch vapors do not condense upon the cooler face of the Web, andrewet the same. The air supplied to the headers 38 and 39 preferably is heated, so that all of the air blasts are hot hot blasts, permitting a much lower temperature to be used in the heating rolls, and drying the paper more uniformly. It will be evident from the description that air blasts are so applied that the moisture will be driven out ofthe drying felts anda maximum y of moisture will be removed from the web itself before it reaches the dryer. v'llhe press rolls will be also heated to assist in the drying action. By heating the air, and applying a blast at the dandy roll, where the web has practically attained its entire formation, the web is not onl dried, but the dandy roll is warmed thus fiirther assisting in drying the web. y the time the web reaches the suction boxes, it has attained a certain degree of heat, and the .suction boxes will act since heated stock-gives up during the pressing process viz the resses. The arrangement is such that when t e web reaches the calenders indicated at 43, it will be thoroughly dried and uniform throughout its extent. j v
I claim 1. In apaper making machine web forrmng mechanism and a dryer, means` for prehmmarily drying the web before it including enters the dryer, and arranged along the path traveled by the web between the forming mechanism and the dryer.
2. In a paper making machine including web forming mechanism and a dryer, means between the web forming mechanism and the dryer for preheating the web and for partially drying the same before it reaches the dr er.
In a paper making machine including web forming mechanism and a dryer, means between the web forming mechanism and the dryer for preheating the web and for partially drying the same before it reaches the dryer, said means including means for directing blasts of air onto the free face of the web.
4. In a paper making machine including web forming mechanism and a dryer, means between the web forming mechanism and the dryer for preheating the web and for partially drying the same before it reaches the dryer. said means including mechanism for directing blasts of air onto the free face of the web, and suction boxes over which the web passes.
5. In a paper making machine including web forming mechanism and a dryer, the combination of suction boxes over which the formed web passes, and means for directing blasts of air onto that face of the formed web remote from the suction boxes.
6. In a paper making machine including web forming mechanism and a dryer, the combination of suction boxes over which the web passes, and means for directing blasts of air onto that face of the formed we'b remote from the suction boxes obliquely and in the direction of motion of the web.
7. In a paper making machine including web forming mechanism and a dryer, the combination of suction boxes over which the formed web passes, means for directing blasts of heated air onto that face of the formed web remote from the suction boxes, and bafies for directing the blasts obliquely onto the web.
. 8. In paper making machines including web forming mechanism and a dryer, the combination of press rolls, and means for directing blasts of air onto the formed we-b as it asses .into the grasp of the rolls.
9. n paper making machines including web forming mechanism and a dryer, the combination of press rolls, and means for directing blasts of air onto the formed web as it passes into the grasp of the rolls, and arranged to impinge obliquely against the web and in the direction of its travel.
10. In paper making machines including web forming mechanism and a dryer, the combination of press rolls, and means for directing blasts of air onto the formed web as it is grasped by the rolls, and means for heatin the lower press roll.
11. n paper making machines, the combination with the press rolls, of means for directing blasts of air onto the formed web as it is grasped by the rolls, and means for heating the lower press roll, said means comprising a trough into which the roll dips, and means for circulating hot water through the trough.
12. In a paper making machine, including web forming mechanism, press rolls and a dryer, means for directing blasts of air onto the opposite faces of the formed web arranged -between the press rolls and the dryer.
13. In a paper making machine, the combination with the drying cylinders and the drying felts, of means independent of the cylinders for applying heated air to the faces of the felts remote from the web.
14. In a paper making machine, the combination with the drying cylinders and the drying felts, of means independent of the cylinders for directing blasts of air against both faces of the felts while they are out of contact with the web to dry said felts.
15. In a paper making machine, the combination with the drying cylinders and the drying felts, of means for directing blasts of air against the faces of the felts remote from the web while the felts are in contact with the web.
16. A dryer comprising 4a plurality of units, each unit comprising a source of heat, and means engaging one face of a web of paper or the like to be dried for supporting and guiding the web in a predetermined relation with respect to the heating means,
said units being arranged to be engaged by the web in succession and with the opposite faces ofthe web in alternation, and means in connection with each unit for heating the face of the web not engaged with the guiding means.
\In testimony whereof I aiix my signature.
GEQRGE STANFORD WITHAM, `Jr.