US2473270A - Cylinder mold papermaking machine - Google Patents

Description

June 14, 1949. ADAMS 2,473,270

CYLINDER MOLD PAP ER MAKING MACHINE Filed Sept. 2, 1944 2 Shets-Sheet 1 ChaRles Sfidams Cew Hekbew-l {.Coves (Ittqmeg June 14, 1949. c. s. ADAMS CYLINDER MOLD PAPER MAKING MACHINE 2 Sheets-Sheet 2 Filed Sept. 2, 1944 wiines s attorney Herbert 6. Cove y Patented June 14.19 49 2,473,270 CYLINDER MOLD PAPEBMAKING MACHINE was s. Adams, Holden, mass, assilnor to Rice Barton Corporation, Worcester, Mass., a corporation .of Massachusetts 1 Application September 2, 1944, Serial No. 552.509

space for the stock so as 30hims.

This invention relates to paper makin machines and more particularly to a machine of the type in which paper pulp is laid on the periphery of a cylinder mold.

' mold, and the paper web is laid on the revolving screen surface. In this construction, centrifugal force set up by the rotating cylinder opposes the fibre laying operation caused by the inward flow of water and tends to produce cavitation or separation of the sheet from the screen surface. Hence, the speed of the cylinder mold must be below that at which cavitation may occur. Moreover, turbulence and a consequent disturbance of the paper formation is created by the over an overflow dam at the opposite side of the cylinder. This involves various changes in direction of the stock fiow which also aid in causing turbulence and disturbing the formation. To minimize the frictional drag of the cylinder the stock has been flowed through the vat in the direction of cylinder rotation, yet a turbulence has resulted from the fact that a large portion of the stock is passed over an overflow and not all of it is deposited on the wire. It has also been proposed to widen the vat circle and provide a large to minimize turbulence; but this does, not take into account the rotation of the cylinder through the stock which creates a frictional drag of the pulp on the web already laid.

It is the primary object of this invention to overcome such problems and to provide a cylinder mold paper making machine in which the paper web is laid on a revolving screen surface and which may be operated at a high or a desired speed and with satisfactory results.

A further object of the invention is to provide a machine in which the centrifugal force set up by the revolving cylinder mold is counteracted and cavitation is prevented.

Another object is to provide a construction of this type in which all of the pulpstock is laid on the screen surface and none is required to overflow for a recycling operation.

A further object is to cause all .of the stock to flow with the revolving wire screen at a rate which minimizes turbulence and particularly to run the stock in a thin layer at the same high speed as the cylinder mold revolves and to cause all of the stock to be laid on the wire. Further objects will be apparentiin the following disclosure.

According to my invention, I propose to form a paper web on'a cylinder .mold screen surface by forcing the stock under a controlled pressure into a converging throat between an impervious wall and the cylinder surface and causing all of the stock to be laid on the screen. The wall is pref-. erably anendless apron which moves in the same direction and at the rate of the screen.

Referring to the drawings illustrating preferred forms of the invention:

Fig. 1 is a somewhat diagrammatic vertical and transverse section through a preferred form of cylinder screen surface revolving through the 20 machine; pulp within the vat, andv some of the pulp climbs i 2 is fragmentary n i n l v rti l up the surface of the screen at the exit side and s n u h he ac ine;

tumbles back in a cascade, thus injuring the web 3 s a detail S owing the mounting of a that'has been formed. The stock is usually flowed kl Strap n h l nke S ppor ing bars; into the vat at one side and the surplus stock goes 2 ig- 4 s a diagrammatic view of the power drive;

Fig. 5 is a.fragmentary sectional view of a modification having rolls upporting the apron; and

Fig. 6 is a fragmentary view showing the mounting of the rolls and associated deckle.

In the embodiment shown in Figs. 1 to 4, the machine comprises a cylinder mold III which may be of standard construction. This comprises a set of spiders ll mounted on a driven shaft l2. A set of longitudinal rods l3 are arranged peripherally of the cylinder and parallel with the axis, and they are suitably secured to the spiders. Surrounding these are coarse and fine mesh screens It with the finer mesh screen forming the outer periphery of the mold. The pulpstock flows beneath the cylinder and the water passes upwardly through the screen mesh into the interior thereof, and it is withdrawn through a central annular passage. This passage is formed by the ring it (Fig. 2) secured to and revolving with an end wall H of the cylinder. The water passes into the annular chamber formed by a stationary ring. shaped part I! and an end wall 20. This space communicates at its bottom with a'pipefl which leads to a suitable apparatus that serves to reduce the pressure within the cylinder mold and to withdraw the water therefrom. The shaft I2 is mounted in suitable bearingsjl carried by a supporting portion of the framework 25, and the auaavo parts may be made in accordance with standard practice.

The primary feature-of my invention lies in introducing the pulpstock to the cylinder screen surface through a narrow converging throat formed in part by the cylinder screen I4 and by a travelling endless and impervious apron 32, which may be made of rubber or rubber coated fabric or other suitable material that is capable of holding the pulpstock in position adjacent to the cylinder mold screen surface.

The shape of the throat is defined by the position of the apron adjacent to the mold, and in order that this may be of a definite configuration, I preferably provide. a supporting surface,

such as a flexible metal plate or cross bars or rolls *herebeneath, and the apron is caused to move at such a rate that it tends to hug that supporting surface. The supporting surface shown in Figs. 1 to 3 is formed by a set of independently adjustable cross bars 36 made of suitable material, such as wood. The bars 36 are individually mounted above the walls 38 and 39 of a vat or supporting structure located therebeneath. Each wooden bar 38 is adapted to be moved radially outwardly relative to the axis of the cylinder mold, so that the shape of the throat may be changed and yet provide the apron with a substantially arcuate support. Each bar has at its opposite ends a supporting post 40 secured thereto. This post freely slides in a socket within a bracket member 41 mounted on the wall 39 of the supporting structure. and it is adjusted vertically by means of a screw is threaded into the bracket. A set screw 43 serves to fix the post in position.

The opposite sides of this converging throat 33 are enclosed by walls formed by arcuate shaped deckles 45 made of hard rubber or other suitable material. These deckles are shaped to rub against the annular plate 11 and associated parts forming the end of the cylinder and to rub against the endless apron 32 therebeneath, as shown in Fig. 2. The deckle may be secured in place by means of iron brackets 41 fastened to the ends of the cross bars 36 of the apron support. The deckle is adlustably held by means of two screws 48 and 49 carried by the bracket. Bythis construction, the deckle is moved in and out with the supporting bars 33 when the latter are adjusted, so that it always contacts with the apron. In ordinary practice, the bars 36 would be moved only to a small extent. Various expedients may be employed to prevent leakage of the pulpstock from the throat. The right hand top cross bar 36 (Fig. 1) is located at such a distance from the cylinder surface that there is room only for the passage of the apron 32 and the thickness of paper web laid thereon, so that this end of the tapering throat 30 is thus closed.

The endless travelling apron 32 is driven and supported by a power driven roll I! at the entrance end of the throat and by a further roll 51. which is preferably power driven. at the exit end of the throat.- The apron is further supported in its travel by rolls l2, 3 and I4 which are suitably mounted on the lower framework of the machine. The roll N is shown as mounted for adjustment to loosen or tighten the apron. This is accomplished by having its bearing housing 56 provided with a vertical screw threaded passage within which is threaded a screw 51. This screw is carried by two supporting brackets 58 and it is suitably adjusted by the hand wheel 59. The parts are so constructed that turning the hand wheel serves to move the bearing housing 58 vertically and thus put the proper tension on the apron.

The roll BI is preferably mounted for adjustment and to be held resiliently against the cylinder lo. Its bearing housings 60 are carried on a pair of levers SI of the first class which are centrally pivoted at 62 on the framework. The lower end of the lever is pivotally connected to a draw bar 6| which passes through a suitable opening in the frame. A hand wheel 68 tightens the tension of a spring 66 which serves to hold the roll 5! and the apron 32 under a resilient pressure against the cylinder mold, as will be understood.

The: leading driving roll maybe mounted on the fixed hearing support '3 suitably carried by the framework. The endless apron 32 is held in driving contact with that roll by means of another roll 1s whose bearings are mounted on a pair of levers l2 pivoted at 13 on the framework. This lever ls also resiliently and adjustably positioned by means of a draw bar I4 and an adjustable hand wheel I5 and a spring I8, so that the apron is caused to Gr p h dr v n roll 50.

A primary feature of this invention involves flowing the pulpstock into the tapering throat 33 at the rate required for laying the web on the wire. It is also preferable that this stock be under a controllable pressure or head. This is accomplished by having the nozzle 30 so shaped as to flt within the space between the apron on the roll 50 and the wire surface of the cylinder. and various expedients may be employed to prevent leakage of stock at this point. The head box 8| has stock supplied to it by means of a valved pipe 82, and suitable regulation of the valve 33 controls the level 34 of the pulpstock in th head box and so regulates the pressure within the throat.

A further feature of this invention involves moving the travelling apron 3: at substantially the same rate as that of the screen surface ll of the cylinder and causing the pulpstock to flow between these two travelling members at substantially the same rate, so that all of the'pulp fibres are laid on the screen surface by the time a given portion of screen reaches the narrow or closed end of the throat. Various expedlents within the knowledge .of those familiar with paper making practice may be adopted for driving the cylinder l3 and the rolls 53 and SI, such as the standard sectional electric drive employed for driving the different rolls of a Fourdrinier paper machine, which includes synchronous motors and resistance controls so arranged that the surface speeds of the various members ma be synchronized or controlled. As illustrated in Fig. 4, the roll I. supported on its bearings may be driven through a speed reduction mechanism Si by an electric motor 32. The cylinder is carried on suitable bearings 24 may be driven through a speed reduction gear mechanism 84 by means of an electric motor ll. Also, the roll ll carried by bearings 60 may be-driven through a speed reduction gear mechanism 96 by means of an electric motor 91. The speed reduction mechanisms are so constructed that when the motors are synchronized they drive the different elements at the same surface rate. It is desirable that the motor 92 which drives the roll 50 give a slightly greater torque than required so. that it tends to feed the apron at a faster rate than it is withdrawn by the driven roll ll, so as to insure Y. is carried on a post '5 that the apron 32 is held structure 30 and does not constrict the throat 80. The cross bars 38 which form the supportin structure for the apron 32 are spaced apart somewhat so that no air prevent the apron from hugging closely to the support. Air and leakage water may bear:- hausted from the vat through opening 98.

I may also use a set of supporting rolls, as illustrated in Figs. 5 and 6, for supporting the apron 32. In order that each of these rolls IBII may be adjustably positioned, its mandrel may be supported at each end in a bearing I02 (Fig. 6) which I 04 that is movable radially of the cylinder I the same as are the bar supports ll above described. That is, the post In! slides in a socket within the bracket I08 mounted on one of the walls of the vat, and the post is vertically adjusted by means of the screw I01 and locked in place by the set screw I08. The deckle construction may be as above described, and wherein the stationary deckle I I0 is carried by an iron bracket III likewise mounted on the top of the bearing structure I02 so that the deckle may be vertically adjusted with the roll I06. These rolls I00 carry the apron without material frictional drag, since they are freely rotatable and move therewith.

Since the paper web is laid on the wire screen of the cylinder, it clings to that wire surface after it has broken contact with the apron 32 when the latter passes over the roll 5|. The paper web is stripped from the cylinder It by means ofan endless blanket 5 which may be made of felt or other suitable material. This blanket passes over a roll H6 suitably mounted on the framework and receives the paper web Ila and transports it to the next stage of treatment. The roll IIE may have its bearings H9 f suitably mounted ona lever I pivoted at IZI on the framework, and the lower end of this lever is resiliently and adjustably positioned by means of a draw bar I23 pivotally connected to the leverand adjusted by means of a hand wheel I24 which compresses a spring I25 and thus holds the blanket tightly against the paper web on the cylinder mold.

The operation of the machine will be apparent in the above disclosure. Pulpstock is introduced under the pressure. of such head as is provided by the head box, and the stock flows through the pipe 80 into the converging throat between the impervious apron 32 and the screen surface I E of the cylinder. The cylinder periphcry and the apron are preferably moving at the same surface rate and the stock enters the throat at substantially that rate so that there is no material frictional drag on the paper web. The water is withdrawn rapidly through the screen surface of the cylinder and removed through the outlet pipe 2|. The paper flbresare laid on the cylinder screen as the stock becomes concentrated through the removal of the water. The fibres retain their criss-cross haphazard and interlaced arrangement as the water is removed, since there is no frictional drag at any point which would tend to straighten out the fibres, except as they are drawn radially towards the cylinder surface. All of the pulp fibres are laid on the screen of the cylinder since there is no provision for overflow of surplus stock. The atmospheric pressure within the cylinder may be reduced to that degree which causes not only an eifectiveiremoval of the water but also a partial drying of the web. Since the apron 32 has an or water pockets can against the supportin 6 impervious surface and the water is removed upwardly through the screen of the cylinder, the Web is laid wholly on the cylinder; and the apron serves merely as a travelling wall defining the I holds the paper stock during the bottom of the cavity or tapering throat 30 which web formation. The cylinder III may have a diameter of from 3 to 8 feet, and the arcuate tapering throat extends for aconsiderable distance around the cylinder and which is suflicient for the paper laying operation. Since the opposed walls formed by the cylinder wire I4 and theapron 32 are moving at the rate of the pulp flow, the pulp is substantially quiescent relative to the walls of the throat. Consequently the intermatting of the fibres or the texture of the paper is determined chiefly by the fact that the fibres are drawn out of suspension by the water moving radially through the The rate of paper making is dethe pulp and the rate of movement of the screen It, as well as the rate at which the water can escape from the throat. 7

It will now be appreciated that various modifications may be made in the construction and equivalent features substituted for those above described. Also, the paper maker may control the texture of the paper and the rate of its formation by varying the shape of the throat and the head of the pulpstock supplied thereto as well as by varying the rates of the moving parts. The above disclosure is, therefore, to be interpreted as illustrating the principles of this invention and my preferred embodiments thereof and not as imposing limitations on the claims appended hereto.

I claim:

1. A cylinder mold paper making machine comprising a rotatable hollow cylinder mold having a pervious, fine mesh wire screen surface arranged for the formation thereon of a paper web deposited from an aqueous suspension of paper pulp stock, means for removing water from the mold interior, means including an endless, impervious,

-' traveling wail beneath and spaced from the mold from a wide stock entrance to a closed end where the paper on the wire contacts with the wall, an adjustable support for said wall located beneath the mold which predetermines the shape of said wall and the size of the throat, controllable driving mechanism for moving the cylinder periphery and the wall towards the closed end of the throat at the same rate, regulatable, means including a conduit having a substantially water-tight connectlon with the wide end of the throat for supplying an aqueous pulp suspension andmaintaining the throat filled under a predetermined hydraulic pressure in the throat, means including a valve in said conduit for varying said hydraulic pressure and governing the rates of water removal and the formation of a paper web which causes the pulp suspension to move beneath the mold as a substantially quiescent body at about the same rate as that of the cylinder periphery while the water is removed upwardly .through the cylinder mold wall, and means for removing the paper web arcuate tapering throat of fixed configurationoonversina from a wide stockentrance at one side race of the mold of all or the introduced stock as the required paper web, and means for progresof the mold to a closed end at the other side where l the paper on the wire contacts with the wall, a support for said wall located beneath and spaced from the mold which predetermines the position of the wall and the shape of the throat. controllable driving mechanism for moving the cylinder mold periphery and the wall'simultaneously towards the closed end or the throat at the same rate.-rezulatable means including a conduit havin: a substantially water-tight connection with the wide entrance of the throat for introducing an aqueous paper stock suspension and maintainin; the throat filled under a controlled hydraulic head which causes the pulpstock to move along the throat at substantially the rate of the mold periphery and which forces the water from the throat upwardly through the periphery of the cylinder mold screen at a rate governed by the head and so causes the deposition on the under sively removing the web from the mold periphery after it has been transported from the throat.

7 CHARLES H. ADAMS.

REFERENCES CITED The iollowins references are or record in the tile ,0! this patent:

UNITED STATES PATENTS Number Name Date 206,107 Hatch July 19, 1978 990,950 Barber May 2, 1911 1,060,122 Proei: Apr. 29, 1913 1,143,981 Babcock June 22, 1915 1,527,297 Emricl: Feb. 24, 1925 1,595,894 Klund Aug, 10, 1926 1,627,882 Berry may 10, 1927 1,699,487 Hinde Jan. 15, 1929 2,005,839 Edge June 25, 1935 2,358,244 Johnson Aug. 22, 1944 2,385,658 Schumacker Dec. 19, 1944 FOREIGN PATENTS Number Country Date 80,980 Germany Apr. 15, 1885 315,224 Great Britain Oct. 23, 1930

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