US2062471A - Apparatus for the manufacture of paper - Google Patents

Description

Dec. 1 1936.

J. M. MURRAY APPARATUS FOR THE MANUFACTURE OF PAPER Filed Jan. 29, 1935 INVENTOR fwu/Zfluunr Patented Dec. 1, 1 936 APPARATUS FOR THE MANUFACTURE OF PAPER,

v James M. Murray, Mount Vernon, N. Y., assignor to International Paper Company, New York, N. Y., a corporation of New York Application January 29, 1935, Serial No.3,962

4 Claims.

This invention relates to improvements in paper making machines and'has particular reference to an improved inlet mechanism for governing the flow of the substantially liquid paper forming stock onto the wire or carrier of Fourdrinier paper machines.

It is a primary object of this invention to provide an inlet mechanism having novel features of construction and arrangement of parts whereby improved flow of the paper making stock onto the Fourdrinier wire or carrier is attained.

Another object of this invention resides in the construction of the inlet so that a maximum flow of the paper stock in a steady stream is afforded and yet the quality of the finished paper is maintained and in many cases improved.

.Another object of this invention resides in the provision of an inlet mechanism formed to include an elongated downwardly extending passage through which the paper forming stock flows, the inlet end of said passage having a greater effective area than the outlet end thereof so that steady even flow of desired velocity of the paper making stock is attained before it is discharged onto the paper forming wire or carrier.

It is another object of this invention to provide adjacent the inlet end a perforated rotating flow evener preferably of the drum type'which serves to control the flow of the paperforming stock from the head or flow box to the inlet end,

of the aforesaid elongated downwardly extending passage thereby obviating any possible undue surging of the paper making stock in the inlet end.

Still another object of this invention is to provide in the head or flow box, a perforated baiiie which extends substantially across the chest angularly from the top to the bottom thereof, thereby retarding the flow of the paper making stock through the head or flow box and against the aforesaid stock evener.

sun a further object of this invention residesof parts hereinafter to be fully described and pointed out in the appended claims.

In the accompanying drawing:

Figure 1 is a view partly in side 'elevationand partly in vertical section of a portion of a Fourdrinier paper making machine showing the application and construction of the improved slice and flow box mechanism comprising the present invention, and

Figure 2 is a front elevation of the slice mechanism showing the combination and construction of elements serving to adjust the effective area of the outlet end of the flow chamber.

The present invention in its preferred embodiment is particularly applicable to the so-called Fourdrinier type of paper making machines,al though it will be appreciated that it may readily be used in connection with other types of paper making machines, as for example, a cylinder type of paper making machine. As is well known by those versed in the art of paper manufacture, in

' a machine of the Fourdrinier type, the pulp or other fibrous material-comprising paper making stock, is supplied in the form of an extremely dilute water suspension, of fibre to a flow or head box, where it is fed through an opening of variable proportions, at a desired rate, upon a traveling wire or carrier. This wire or carrier, preferably of the endless type,'is trained around two spaced rolls, the roll near the flow box or inlet end being referred to as the breast roll, and the roll at the other or discharge end being commonly called the couch roll.

- In'the figures of the accompanying drawing, the flow or head box is designated by the numeral I0, and the stock discharge passage constituting a primary feature of this invention by the numeral H. The outlet of the discharge passage is provided with the usual apron I! mounted on an apron plate (not shown) and the Fourdrinier wire or belt l3 extends around the breast roll M, the upper peripheral portion of which is disposed substantially in the horizontal plane of the apron l2. Conventional deckle strap mechanism, not shown, is used. 5 The distribution and rate of flow of the paper forming stock on the wire I3 is a matter of great importance in obtaining successfuL and economical operation of paper machines of this kind. It is, of course, desirable first to provide a mechanism so constructed as to permit the fibrous paper forming stock to distribute itself evenly and uniformly over the full width of the wire so that the fibres will be properly and uniformly interweaved and matted to produce a paper of desired uniform grade, devoid of streaks and of desirable strength and other. properties, and, second, to provide for a uniform and rapid feeding of the paper stock on the wire to the end of obtaining the maximum output of the machine, consistent, of course, with the formation of a good grade of paper. It is to the attainment of these general ends that the present invention is directed.

In the specific form illustrated the front wall I5 of the head or flow box l0 extends to a considerable height above the plane of the Fourdrinier wire or belt but is not as high as the rear wall l6 of the flow or head box. The paper forming stock, coming from thestock preparation mechanism, flows through the conduit l1 into the head or flow box. To prevent undue surging of the stock and to assist in evening the rate of flow thereof, a perforated baflle l8 made of any suitable material is positioned in the flow box and extends angularly from the front edge of the conduit to the top of the flow box. As the stock passes upwardly through the head box it passes through a rotating fiow evener l9 driven by any conventional mechanism (not shown), the said evener being preferably of the drum type and having perforations 20 provided therein. The rotation of this evener also serves to direct in a positive manner the stock over the top edge 2| of the front wall of the flow box. As will be noted this edge is rounded to prevent any accumulation of stock. The effective gravitational head of stock obtained by the above construction will be equal to the height of the front wall of the fiow or head box.

The stock driven over the edge 2| by the rotating evener, next passes into a downwardly inclined passage or flat nozzle II which extends transversely across the paper making machine.

As will be noted the front and rear walls 22 and 23 respectively converge toward each other so that the effective area of discharge end 24 of the nozzle is considerably smaller than the effective area of the inlet end 25 thereof. It has been found that uniform formation of a sheet is enhanced when the rate of flow of the paper making stock on the wire is substantially equal to the linear speed of the Fourdrinier wire or belt. By proper construction the angle of convergence of the front and rear wall of the nozzle will be such as to equalize the rate of flow of the stock and the linear speed of the wire and to reduce the friction of the moving stock on the nozzle to a minimum. The rear wall 23 of the nozzle and the front wall l5 of the flow box may constitute respectively the rear and front walls of a frame work 26 of conventional design, the front wall being sufficiently rigid and strong to withstand a progressively increasing pressure from top to bottom due to the pressure of the stock thereagainst. Similarly the front wall of the nozzle is also braced as well as the end walls 21 thereof, by any desired typ of bracing construction.

The front wall of the nozzle constitutes in eflect the slice and is provided with a lip 28 pivotally or hingedly connected thereto. Irrespective of the method employed to secure the lip to the front wall of the nozzle it must offer no obstruction to the paper making stock in its passage down the nozzle and onto the paper making screen or wire.

To correct localized variations in the thickness of the forming web of fibrous material means to spaced intervals. The upper end of each red is in threaded engagement with a boss 30 supported by a bracket 32 extending across the width of the front plate or wall 22, the bracket itself being secured to the bracing members 3| of the said plate. Lock nuts 33 are provided on either side of each rod 29 and serve to hold it in any adjusted position. It will be appreciated that should any local variation in thickness of the forming web appear it may be controlled by adjusting the rod located at that point where thevariation occurs.

Means are also provided to adjust the plate 22 in its own plane and comprise rods 40 pivotally connected to the upper end thereof. They are threaded at their upper end 4| and engaged by nuts 42 above and below the bosses 43 on the stirrups 44 by which the rods 40 are hung from eccentrics 34 on the transverse shaft 35. At one end the shaft is provided with a worm wheel 36 meshing with a worm 31 supported in the bracket 38 and operated by a handwheel 39. The rotation of the shaft 35 and cams by means of the handwheel, raises and lowers the several adjusting rods to an equal degree, thus increasing or de creasing the thickness of the stock sheet on the screen across the entire width of the latter. The rods 40 are pivotally connected to the plate 22 to permit the latter to be shifted to change the angle of convergence of the stock nozzle to adapt the device to handle stock of different consistencies and type of fibre employed. It will of course be appreciated that other types of adjusting mechanism may be used depending upon individual desire without departing from the scope of the invention.

In view of the foregoing it will be seen that the present invention provides a stock discharge mechanism for paper making machines wherein many improved adjustments and stock controlling devices are provided for regulating the character and form of the flow space between the slice and the wire and for controlling the velocity of the paper forming stock. It will be observed that the fiat nozzle construction in combination with the fiow evener and perforated baifle provides an effective and economic mechanism for regulating the velocity of the moving paper making stock so that it will be equal to the linear speed of the wire as it is deposited thereon. This will insure an equal and proper interfelting and matting of the fibers so that a sheet having uniform formation characteristics will be produced.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and

that changes may be made therein without departing from the scope of the invention as defined in the appended claims. 4

What is claimed as new is:

1. In a paper machine, a head box, means to convey stock thereto, a forming wire, means for conveying stock from said head box to said wire comprising a downwardly inclined nozzle having converging side walls, flow evening means located adjacent the inlet end of said nozzle and means in said head box to prevent the surging ofstock against said evening means.

2. In a paper machine, a head box, means to convey stock thereto, a forming wire, means for conveying stock from said head box to said wire comprising a downwardly inclined nozzle having converging side walls, a rotatably mounted flow 2,062,471 3 evening drum located adjacent the inlet end of means, and a perforated baflle to prevent surge said nozzle and means in said head box to prevent of stock against said flow evener. the surging of stock against said evening means, 4. In a head box, means to introduce stock said evening means comprising a perforated baflie thereinto, stock discharge means located at the 5 positioned angularly across the path of flow of the upper end of said head box, a rotatably mounted 5 stock in said head box. flow evener located adjacent said discharge means, 3. In a head box, means at the lower end thereand a perforated bafl'le to prevent surge of stock of to receive stock, stock discharge means located against said flow evener positioned angularly at the upper end thereof, a rotatably mounted across the path of flow of stock in said head box.

10 flow evener located adjacent said discharge JAMES M. MURRAY. 10

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