US1919312A - Paper drier - Google Patents

Description

July 25, 1933. J w VEDDER I 1,919,312

' PAPER DRIER Filed Dec. 29, 1930 getherroThe web ofpaper' passes around PatentedJuly 25, 1933 UNITED; STATE 5" "PA-TENTOFF'CE JOHN WARREN VEDDIJR, or WORCESTER, MAssAonusEr'rs;Assn-Non To amnimn roN I & FALES, rivcoaronarnngor WORCESTER, MASSACHUSETTS, A eonronarronor 4 MASSACHUSETTS if PAPER DRIER Application'filedDecember 29, 1930.' Serial No. 505,268.

The principal object of this invention is to" provide for allowing paper in a paper drier used in connection with paper making machinery to shrink naturally, and where: by the undue reduction in'width of the paper now usual and'the corresponding reduction in thestrength of the web will be avoided.

10ther objects and advantages of the invention will appear hereinafter.

Reference is to be had tothe accompanying drawing, in which 3 Fig. 1 is a side view of a paper drier partially diagrammatic, showing the application of this inventionthereto; and

Fig.2 is anend view showing one drying drums. a i

The ordinary paper dri er: on the market consists of a seriesof dryingdrums arranged I in an upper and lower tier and geared toeach drum and must'v necessarily move in ac-v cordance with the surface speed of the drum.

Two felts are used, one to :press the paper against one tier of drums, and the :other v against the other tier. 1 Thesefelts are 'driv en at'the surface speed of the drumsby the drums, and tend to force the paper still more accurately to move at the same speed as the surface speed of the drums." The pur-. pose, of course, of the drier is to dry-the-paper and the efiect is-not only to dry but toshrink, it. Inasmuch as these driers are constructed so that the paperv cannot shrink lengthwise, the entire shrinkage occurs cross- V wise. The result is that when the paper-is dried it has shrunk unduly in width and this shrinkage is not uniform. Furthermoreas the natural tendency of the paper is to shrink while on the surface of each of the drums and between the drums and that tendency is pracavoided by eliminating-the gears and employing pulleys and a belt to drive the drums.

- The pulleys are graduated in size toprovide for the shrinkage.

Furthermore, the belt will be able to slip whensubjected to undue strain caused by the shrinkage of the paper er, drums.

and allow the paper to go through withoutso much tension being appliedto it byeach drum.

The result of this is that the paper is allowed 0 shrink longitudinally in a natural man-.555

ner,'and therefore, does not shrinkunduly laterally and isnot weakened byshrinkage.

The web ofpaper 10 passes throughout, a a

drying machine comprising aseries of internally steam heated drying drums llarranged' in two tiers, Olle'bBlOW and one above and staggered, so that the machine occupies practicallythe same spaceas the old machines containingthe same number of drums. I I

Onthe shaft or journal 12 ofeach drum 1s located a pulley 13.. A'belt 14 is threaded over and under] these pulleys 13 as shown,

and driven from any desired source of power, preferablythrough the first upperand lowthe drums in the proper direction to feedthe The result, of course,is to drive;7o

web 10 through from oneyend to the other.-

Abelttightener 16 can be employed if desired. V

od practical, the drier can be split up into two ormore sections with a belt'for'each one;

In case the number of drums desired to use in a drier is too large to make thifsmeth- The usuallfelts 17 and 18are employed. for

holding, the web against-the various drums,

these felts extending practically halfway around each drum, one felt being used'for thelow'er tier ofdrums and onefor the up-c one at the end at which the'paper' leaves the a drier is the largest one. The others vary the other, gradually increasing in size from the entrance to'the discharge end, but the, total increase is very small. Infthis way the drums near the discharge end rotate a little slower progressively all the way from one end of the drier to theother. This is to, take very slight. gradations from one end to up the decrease in length of the web due to 1 l shrinkage. The change in diameter of the pulleys may be produced by turning them to different diameters, but usually they are all turned the same size and lagging is applied to effect the difference; As the web enters the machine it goes around the first drum and is held thereon by the felt and then passes around the second drum.. Naturally being dried a little more, the webaon the second drumshrinks slightly and this drum, although exactly the same size as the first drum, is rotated a little slow-v er so that the shrink in the web of paper will be taken care of. The speed of the web around this drum will be enough less to avoid any extreme tensionon the webbetween the drums. The same condition exists all the way through the machine and therefore the web on each drum, although tightly 'held tothe surface thereof and rotating at the speed of the drum, will not be pulled to piecesbythe last drum over which it goes and thereby weakened. Furthermore, it will lie naturally on the surface of each drum, so that the shrinkage can take place'in the vnatural manners Although I have illustrated and described only a single form of the invention, I am aware of the fact that modifications can be made'therein by any person skilled in the art without departingfrom the scope of the invention as expressed in the claims. Therefore I do not wish to be limited tothe'exact .form'shown, but whatI do claim is 1. In a drier for web material, the com bination of a series of heateddrier drums of the same diameter over which the web is led from one drum to another, a pulley on the shaft of each drum, said pulleys being of different sizes, those at the wet end being progressively smaller'than those at the discharge end, a belt passing around said pulleys,

one after the other, means for driving one ormore of the drums from a source of power so that the rest of the drums will be driven at progressively lower speeds by the belt as the web progresses through the series but these speeds will not be positive, and'a felt arranged to pass over the web throughout the series of driers so thatrthe driving of the driers by the belt and the driving of the driers by the felt, both of which are non-posic tive, will controleach other and allow the drums to slip-on the felt sufficiently to allow for the lengthwise paper shrinkage.-

2. In a paper drier, the combination of a series of internal heated paper drying drums, each drum having a shaft, a pulley on each shaft, the pulleys at the receiving end of the drier being of progressively smaller diameter than those at the discharge end, a belt extending over all thepulleys on the drum in a regular series, means for driving one of the series of'drums from an external source of paper on the drums,. whereby the natural shrinkage of thecweb longitudinally will be accommodated by the slower speed of the drums from one end of the series to the other and the shrinkage will be prevented from; being transmitted to the drums positivelyby the fact that the felts will slip on the drums t the lower drums to drive-the drums fric-- tiona-lly, means for driving one ofthe drums from an external source of power, and endless" felts extending over the drums for holding the paper against therespective drums, said felts being driven'by contact with the paper around thedrums, whereby the friction of. the belts" on their pulleys plus the pull of the paper will allow the drums to slip on the felts 'to' accommodate the longitudinal shrinkage of the 'paper'web, v 7 I g JOHN WARREN vEDDE c power, and a felt passing over the web of. l

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