Патент USA US2408505код для вставки
Oct. l', 1946', SBERGSTEIN ' 2,408,504 xmms Foa comme wEßs Find sept. 14. 1944 2 sheets-sheet 1 Il u. ,.„lÁN cle-ooo* .. È i ..5 b 'Sn/nuez. BERGSTEIN, BY 0¢t~ l, 1946. . s. BERGsTElN mns Foa coA'rINGvwEBs Filed sept. 14, 1944 ~ 2,408,504 ~ ` 2 sheets-snip; h o I “2o O o . O O O O O 59mm. Benssreuv, I INVENÍOR. BY Patented Oct. 1, 1946 2,408,504 UNITED. STATES PATENT orrica . ` , . . _ 2,408,504 _ MEANS Fon coA'rING WEBS Samuel Bergstein, Cincinnati, Ohio.> assignor to A Robert Motrèrie: Bergstein and Frank David Berg. stein, trus Application September 14, 1944, Serial No. 554,022 My invention relates to devices for applying a continuous coating of lacquer or other coating materials to a continuous web of paper or the like. ' It is an object of my invention to provide a >mechanism whereby coatings containing solvents may be applied to the web without any material loss of the solvent during the actual coating op-, eration. Thus, the characteristics of a supply ofv the coating material at the coating station is not subject to progressive changes due to solvent loss during the coating operation. A further obiect of my invention is to provide an extremely simple and low cost coating mech anism which is adjustable' to a full range of webs within the width limit of the machine, 2 but spaced therefrom so that the web must fol.. low a short tangential path in reaching the doc- ‘ tor blade. Side members are provided which en-- gage the surface of the web upon the cylinder, and are appropriately shaped to do this. The side members, however, have extensions, the lower edges of which follow the adjacent tan _ gential path. They also have end portions closely approaching surfaces of the knife or doctor. The doctor and the side members together form with the web a reservoir in which a. relatively small - quantity of the coating substance may be main tained, the side members acting as dams for this ' ’ reservoir and permitting both the use ïof lower viscosity materials and the maintenance of very much less volume in the reservoir than would which is readily adjustable to the coating of films of different thicknesses, and which provides a be possible otherwise. v In the drawings, a'roll or supply of the web _ smooth, continuous coating on the web with a to be coated is indicated at I, mounted upon a ' l 20 suitable shaft or mandrel 2, which in turn may A further object of my invention is the pro:` be supported by a conventional back stand or vision of means for coating which will prevent unwinding stand. It should be understood that or minimize loss of the coating substance upon the unwinder may be va separate instrumentality stoppage of the machine or breakage of the web. These and other objects of my invention, 25 or may be part of a single machine, as a mat ter of design. The unwinding device will be which will b__e set forth hereinafter or will be ap provided with a brake la to prevent overrun parent to one skilled in lthe art upon reading this minimum of waste and Spoilage. ning and to tension the web. _ specification, I .accomplish by that certain con procedure of which I shall now describe an ex~ emplary embodiment. , It should be understood also that instead of rectly unwinding the _web from a rolled sup struction and arrangement of parts and in that 30 pLv and coating it as shown in the figures of this v_Reference is made to the drawings wherein: Figure 1 is a diagrammatic pian view `of a ' mechanism according to my invention, the sup ~ case, the web may proceed to my mechanism from some other source oi' supply, such as al previous machine acting on the web, in which event pre cautions will be taken to restrain the web as ply tank being shown in dottedlines, the cover 35 aforesaid. so that it may be tensioned. ’ being omitted. . ’ Figure 2 is a diagrammatic sectional view of . the mechanism shownin Figure 1. taken along the center line of that figure. Figure 3 is a diagrammatic plan view of a now 40 control means. ‘ _ Figure 4 is a partial sectional view of the tank showing flow control means. The web 3 passes around a break-over roll «i on its way to a draw roll or cylinder 5. The ‘ break-over roll may, if desired, be surfaced with rubber. ' ' I prefer to drive the draw roll or cylinder l; and the provision of a variable speed drive, in dicated at I8 between the roll 5 and a source of power 20, enables me at this point to control the speed of travel of the web 3 as it is being Figure 5 is a partial isometric view oi' the cover. Figure 6 is a partial isometric view of a side 45 coated. such speed variation being .desirable in member showing adjustable means. ' view of the nature oi' various coating substances Briefly, in the practice of- my invention, -Iy in the production of coatings o: desired weights. - cause a web to be coated to pass around the sur The break-over roll l is located closely ad face of a relatively large diameter cylinder or jacent to the draw roll 5. As the draw roll re draw roll. tensioning the web as this is done so as to cause it to lie smoothly against the sur- . sq volves in the direction of the arrow, the web is caused to pass tightly around its surface for a face of the cylinder without wrinkles or buckles. „_ considerable portion of its circumference, thus I carry the web away from the surface of the causing the web to be smoothed out and freed of cylinder and beneath a knife or doctor which wrinkles. l ` ls located close to the surface of the cylinder is An adjustable blade or scraper 8 is suitably 2,408,504 3 ' mounted in a way to be contacted by the web 3 at a position close to but not at the surface of the draw roll 5. The scraper or knife may be mounted in various ways as, for example, at its ends in side frames (not shown), of the machine» is’preferabiy rounded, as shown inthe drawings, lso that itmay be adjusted to different angular relationships with the web, and means for an gular adjustment are also provided. „I have shown the knife or doctor 6 mounted on a shaft extending transversely across the machine. and provided with set screws; but other mountings _ and adjustment means may be employed. tity to replenish the supply of coating material thereat. The iiow will be regulated in accordance with the viscosity of the coating material and the speed of travel of the web. The tank may be constructed and operated in a variety of ways. I prefer to provide an elon gated tank which, as shown, extends across the width of the area to be coated, and is also 15 equipped with a suitable cover to prevent undue The angular relation of the knife to the web is one of the factors controlling thethickness of _the applied coating. ' After passing beneath the doctor or knife 6, the web 3 is drawn away at an agle tothe tan gent and passes between upper and lower pinch rolls 1 and 8. . formof a slot or through a series of small, spaced orifices. Suitable means are provided for the regulation of flow of the coating material so as to deliver to the coating knife the proper quan Or it may be otherwise mounted on or in a mem ber extending across between the side frames. It is also made rotatably adjustable as to posi-' tion. The working surface of the, doctor or knife 4 trolled stream flows out of the lower end of this tapered base through a narrow channel in the ^ Adjustable, shaped side members 9 and l0 are provided. 'The under surfaces of these members have a portion i2 configured to conform to the surface of the web on the surface of _the draw roll 5, and another portion I3 contoured to con form to the web in its short tangential travel be-l tween the surface of the draw roll 5 and the act evaporation of solvent. Such a tank may be pro vided at its base with a series of outlet perfora tions 23 (Figure 4) and also with a sliding plate Y 24, similarly perforated as at 25, and serving both as a means for opening and closing the perfora tions and asa means for regulating the volume of flow of the coating substance. For this pur pose it may be provided at one end with an ad justabie stop 26 to control the open position and at the other end with a fixed stop 21 to determine a closed position. It may be spring-urged as at 28 to the closed position and moved to open posi tion, if desired, by solenoid 29 or other means con nected as by leads 30 to the circuit of the main drive for roll 5. Thus if the machine is stopped, the flow of coating substance from the tank will cease automatically. ` ing surface of the vknife or doctor B. The ex My invention is particularly adapted to coating treme ends of the side members are contoured, as with lacquers or other substances in solution in at it, to respond to the knife or doctor 6 in one’ position thereof. Where the knife or doctor must v35 volatile solvents. lExamples are: vinyl resins or other resins dissolved in acetone, alcohol, or sim ilar solvents. The great bulk of the coating ma- terial is retained in a. tank so that it is not sub stituted, or the side members 9 and I0 may be ject to loss o_f solvent during the coating opera provided with adjustable extensions, indicated at i5, to permit them to be adjusted 'to various 40 tion. as would be the case, for example, were the coating substance maintained in the conventional positions of the knife or doctor. These exten 'fountain and roller coating mechanism. When sions may be plates, held to the `side member. by such mechanisms are employed with coating ma abolt ZI, and slotted as at 22 to permit appro terials containing volatile solvents, there is a priate adjustment. constant and large solvent loss which increases The side members 9 and i0 may be so placed costs because. of the need for adding additional as to rest on extreme marginal portions of the solvent from time to time. Solvent loss also web 3; and they serve as dams so that avery makes the coating operation difficult because of small quantity of the coating material may be progressive changes in the viscosity of the coat continuously confined by the knife, the web, and ing material as the solvent evaporates. In' my two side members.y Coating material is thus not. , apparatus and- process, a much better control of lost off the edges of the web as in many coating the coating is obtained because the quantity ex \ operations, nor is it necessary to minimize this posed under conditions where solvent eva-poration loss by maintaining a high viscosity in the coat can occur is very greatly minimized, while the ing material.> The members 9 and l0 may be great bulk of the coating material is maintained caused to rest at their proper positions by gravity, , in a closed tank where evaporation is minimized wherefore, I have shown them slotted, as at I6, be adjusted to other rotative positions, other ap propriately shaped side members may be sub the cross member il between the frames of the ' machine engaging in these slots. The members or prevented. It should be noted, however, that - the utility of my invention is not confined to sol vent type coatings, but may be'employed for vari 9 and i0 are thus able to ride up and down as may be required for webs of different or differing 60 ous other types. Emulsions in water may be ap plied in accordance with my invention and, in thicknesses; but because it is a very short tangen deed, coatings which require heat for the control tial path of travel for the web between the sur of~ viscosity'may likewise be employed together face of the draw roll 5 and the line of contact of with means for applying heat to the tank and the doctor 6 with the web, the web is maintained in close engagement with the undersides of the 65 means, such as enclosed'electric heaters in the scraper blade to maintain the temperature of the ' members 9 and it) by the tension aforesaid. coating substance, so long-as the web being coated The weight of the members 9 and' I 0 constitutes is capable of withstanding the heats involved. very little drag on the web. Since these elements The adjustment of my mechanism, when overlie marginal edges of the web, these edges re v.main uncoated; but they may be later trimmed oil 70 changing from one width of web to another, is extremely simple and involves only the proper by knives or shearing means, as will be readily understood. ' . A tank Il for coating material is mounted above the surface of the draw roll. Thisv tank is tapered _ at its base, and the coating material in a con -positioning of the side members so that they rest upon the marginal edges of the particular width of web being coated. Where it is desired to coat ' 75 different parts _of the same web with different __ :mossosl ' 6 9 and i0. The direction of tangential travel of substances, one or more additional members, like - the web from the draw roll 6 to the blade is pref those shown at 9 and I0, may be employed inter ' mediate in the tank the I1others or suitable and with separate suitable tanksd_ivisions4 as mal1 _erably inclined downwardly, as shown; and the path is short, being at most several inches, so that there is no great area of unsupported web be desired, so that different coating materials may be applied -to different areas ,of the web. The coating material which flows from the ‘ between the draw-roll and the doctor blade. A cover member i8 may be used in connection' with my apparatus, having depending side plates tank l1 is delivered directly onto the web and is i8a, and being'supported on the side frames of trapped in the pool aforesaid formed'by the-de# pression of the web itself between the blade and 10 the machine by extensions i8b in such a way as to cover the side members, the doctor bladev and the draw roll with ~the side members acting as the reservoir of material formed on the web.- It dams. The amount of material held in this pool will be slotted as at 82 to receive the nose of the or reservoir at any given time `>is small, >so that the coating operation may ‘be caused to occur so Modifications may be made in my invention rapidly that evaporation prior to coating is ren 15. without. departing from the spirit of it._ Having dered immaterial. ~The actual thickness _or thus described my invention in an exemplary em weight of the applied _coating iscontrolled by bòdiment, what I claim as new-»and desire to- se»> the adjustment of the blade. The coating occurs tank. uniformly across the » face of the web. . y ' cure by Letters Patent is: The ‘ 1. In a coating machine, a draw roll, a doctor amount of flow from the tank i1 is controlled, 20 blade having an operative edge located adjacent . so that it is necessary only to start the machine.' but spaced from the surface of said draw roll, establish the desired _relationship between the means for moving a web under tension around weight of coating desired, the speed of travel of!> the web, and the angularity of the knife, and ' a substantial circumferential portion of said draw roll and thence tangentially to the operating then determine the amount of flow from the tank edge of said doctor blade, means for introducing I1 which willvmaintain the reservoir in the de pression of the web. Once this adjustment has _, coating material ontol said web -adjacent said , been secured, the machine will continue indeñ- 1 nitely to apply a continuous film -uniformly to the web. . » As shown in. Figure l, the lower pinch roll 8 ' 3" .c I is preferably a continuous cylinder contacting-the doctor blade so as to cause said material to dam up against said doctor blade, and means for ad justing the amount of coating applied to said - web by angular adjustment o! said doctor blade with respect to the tangential path of travel .of uncoated under side of the web. Instead of a said blade. continuous upper cylinder, I. may employ small friction discs 1, mounted upona shaft 1a, so that these vdiscs may be caused to contact the web on its uncoated marginal edges. The shaft 'ia may blade having an operative 'edge located adjacent but spaced from the surface of said draw roll, 2. In a coating'machine, la draw roll, a doctor'~ means for moving a web under tension around a substantial circumferential portion of said draw be driven by suitable means, such as a motor 3l, . at a slightly higher rate of speed than the speed roll and thence tangentially to the operating edge of web travel, and continuously, i.-e. they con 404 of said doctor blade, means for introducing coat tinue to rotate even though the main drive is idle. ing material onto said web adjacent said doctor f When the machine is stopped, as for example to blade- so- as to cause said material to dam up make an adjustment, the tension rollers or discs against said doctor blade, and means for adjust 1 serve to maintain tension in the web so that, ' ing the amount of coating appliedv to said web whether moving or stationary, the web is at all by angular adjustment oi said doctor blade with times held in tension against the blade or doctor 45 respect to thetangential path of travel of said . S. The maintenance of the coating material in blade, and means resting on the margins of said -the reservoir is thus assured.’ The use of the web and shaped to conform in part to the sur friction discs 1 instead of a. continuous roll pre- ' ` face of said draw roll, in part to said tangential `vents any displacement of the coating by such path oi' travel, and to a i’ace of said doctor blade. _ Y a roll if the coating has nothardened 'or set by 5o >3. The structure claimed in claim -2 wherein >the time the web reaches elements 'l and 8. the means for introducing the coated material After leaving elements 'I and 8, the web may onto said web includes an overhead tank with ypass through a drying tunnel, it desired, and adjustable outlet means. ' thereafter may be rewound or sheeted in the cus ' 4. The structure claimed in claim 2 wherein ' tomary manner or may be conducted directly to 55 the means for introducing the coating material other mechanisms to operate upon it, as for ex onto said web includes an overhead tank with ample, mechanisms i'or_ bag formation. Such adjustable outlet means, said tank being closed `other mechanisms'form no limitation upon my except for `said outlet means whereby to mini mize yevaporation of solvent from a coating sub invention. , ' , , From the above, it will be apparent that my invention provides a simple means for effectively supplying a, uniform coating to- a web. No elab crate doctor blades or coating rollers are required, the coating being done by a simple blade adjust able directly on the web. \ Except. for a minimum quantity reservoir oi the coating material on the4 web itself, the coating materialis retained in a closed container or tank whereby loss oi.' solvent is minimized; The coating is done immediately after the web has passed around the draw roll l, so that the web is positively maintained in a smooth and unwrinkled condition as the coating is applied. The low quantity reservoir of coating material is formed on the web itself, and is main tained by the doctor blade and the side members 30 stance. - ' \ ' 5. The structure claimed in claim 2 wherein the means for introducing the coating material onto said web includes an overhead tank with 65 adjustable outlet means, said tank being closed except for said outlet means whereby to mini „ mize evaporation o! solvent from a coating sub stance, and having means to interrupt the flow oí the coating material upon interruption of the 70`movement. of said web. e. The strucmre claimed in ciaim 2 wherein ' ' means resting on the margins ofsaid-web have attheir ends means adjustable to conform to the face oi’ said doctor blade in varyingpositions 75 thereof. » , 2,409,504 ' ' 7 7. The structure claimed in claim 2 wherein said means resting on the margins of said web have at their ends means adjustable to conform to the face of said ldoctor blade in varying posi tions thereof, and wherein a cover member is engaging uncoated marginal portions of said web. said frictional discs being driven, and said draw roll being likewise driven, the drive for said fric tion discs being operative independently of the drive for said draw roll. provided enclosing said doctor blade, said mem 11. In a coating machine, means for applying bers resting on the margins of said web as said braking resistance to a web, a break-over roll, an web is being coated; adjacent draw roll, a doctor blade near the sur 8. The structure claimed in claim 2 wherein face of said draw roll but spaced therefrom and said means resting on the margins of said web 10 means for engaging and moving a web under ten have at their ends means adjustable to conform sion, in the order named, said break-over roll to the face of said doctor blade in varying posi acting to conduct said web to the surface of said tions thereof, and wherein a cover member is pro draw roll, said draw roll being positioned with vided enclosing said doctor blade, said members respect to said break-over> roll and said doctor resting on the margins of said web as said web 15 blade to cause the web to pass around a substan ' is being coated,‘said means for moving said web tial portion of its surface, said draw roll and said under tension comprising initial feeding means engaging and moving means being located with and retarding means therefor, and subsequent means for moving the web, said last mentioned means comprising a lower roll contacting an un coated face of said web and upper coacting fric tion discs engaging uncoated marginal portions respect to said doctor blade so as to cause said web to move tangentially to engage an edge of said doctor blade and then to move at an angle to the tangent toward said engaging and moving means, the said tangent being downwardly di of sai(- web. rected. and means for delivering coating material 9. The structure claimed in claim 2 wherein into the bight between said web and said doctor said means resting on the margins of said web 26 blade. have at their ends means adjustable to conform l2. The structure claimed in claim 11 wherein to the face of said doctor blade in varying posi said engaging and moving means operate contin tions thereof, and wherein a cover member is uously at a peripheral speed slightly in excess of provided enclosing said doctor blade, said mem the speed of travel of said web. bers resting on the margins oi' said web as said 30 13. The structure claimed in claim 11 wherein web is being coated, said means for moving said said engaging and moving means operate con web under tension comprising initial feeding tinuously at a peripheral speed slightly in excess means and retarding means therefor, and sub oi' the speed of travel __of said web, and wherein sequent means for moving the web. said means there are means engaging marginal portions of comprising a lower- roll contacting an uncoated 35 said web and resting thereon, said means con face of said web and upper coacting friction discs forming to said web on the surface of said draw engaging uncosted marginal portions voi' said roll, following said tangential path and conform web, said frictionai discs being driven,- and said insr to a surface oi.' said doctor blade. ^ draw roll being likewise driven. 14. The structure claimed in claim 11 wherein 10; The structure claimed in`claim 2 wherein` 4:0 said engaging and moving means operate con said means resting on .the margins of said web tinuously at a peripheral speed slightly in excess have at their ends means adjustable to conform of the speed of travel of said web, and wherein to the face of said doctor blade in varying posi there are means engaging marginal portions of tions thereof, and wherein a cover member is said web and resting thereon. said means con provided enclosing said doctor blade, said mem 45 forming to said web on the surface of said draw bers resting on the margins of said web as said roll. following said tangential path and conform web is being coated, said means for moving said ing to al surface of said doctor blade, and means web under tension comprising initial feeding for maintaining the positions of said last men means and retarding means therefor. and subse tioned members >in :the horizontal plane, while quent means for moving the web, said means 60 leaving said .members free for gravity actuated comprising a lower rollv contacting an uncoated vertical movement. face of said web and upper coacting friction discs SAMUEL BERGSTEIN.