US2421829A - Fourdrinier papermaking machine - Google Patents

Description

June 10, 1947. E, WQCLEM' 2,421,829 l FOURDRINIER PAPE IIAKING ACHINE l v v Filed .my as; 1944 Fiel;

Patented June 10, 1947 I FOURDRINIER'PAPERMAKING MACHINE Everett W. Clem, Shrewsbury, Mass., assigner to Rice Barton Corporation, Worcester, Mass., a corporation of Massachusetts Application July 28, 19445-Seral N0. 546,956

' 5 claims. l

This invention relates to a. Fourdrinier paper making machine and more particularly to the breast; roll section thereof.

In a standard paper making machine, the endless wire on which the paper web is laid passes from a. breast roll over a set of table rolls and ultimately returns beneath the table from an end couch roll to the breast roll. The table rolls are customarily mounted on side bars which are arranged to be shaken so as to move the rolls end- Wise and aid in laying the paper libres. The breast roll may be mounted either on the side bars or on a separate pedestal and so arranged that it too may be shaken endwise with the table lrolls. In a narrow machine, the table rolls may be about 4 inches in diameter, while in a wide machine they may be to 12 inches in diameter. They are customarily placed quite close together so as to give proper support for the wire and to aid in the removal of the water from the pulp thereon. The breast roll, aboutwhich the wire passes as'it comes from the rear of the machine, is made of large diameter to prevent breaking or injuring the wire, and usually its diameter has been in the range of from to 28. Hence the center of the breast roll must be located at a considerable distance from the rst table roll, and there is a. corresponding distance between the tops of the rolls which contact tangentially with the wire. Consequently, the wire is unsupported for a space of 15 to 18 inches. The suspension of paper pulp in water usually flows from a head box and over an apron onto the wire on a line located over the breast roll. The weight of the pulp on the unsupported portion of the wire between the breast roll and the rst table roll causes the wire to sag, and so creates a serious problem in that the pulp will run out at the sides of the wire through the hollow that is formed.

One remedy for this has been to support the wire between these rst two rolls by means of a stationary board over which the Wire` drags.

But this creates friction and unduly wears the r wire and so requires frequent replacement or reconditioning of the parts. Various other a1'- rangements of the breast and table rolls and the slice have been made but they have not satisfied the present requirements. For example, the top of the breast roll has been located about an inch below the plane of the wire on the table rolls; but this has involved the same wide separation between the tops of the breast roll and the first table roll. Also, the slice has been arranged in various positions, such as over a table roll, but the weight of the pulp has been carried on the comparatively long-stretch of wire between the large diameter breast roll and the 'first table roll. In some cases, the pulp has been owed onto an uphill portion of the wire, where the breast roll has been located at a lower level than the table rolls. This uphill movement, as well as a waterfall from a high apron onto the wire, should be avoided for most methods of fibre laying. It. is desirable that the pulp issue in a substantially horizontal direction immediately onto the wire and in the direction in which the wire is travelling. That is, the apron on which the pulp flows from the head box should be in substantially the plane of the top surface of the wire so that the pulp will travel forward without undue agitation.

The primary object of this invention is to overcome these problems and to reduce the diameter of the breast roll, or the first roll in the table section beneath the apron, so that it will approximate the diameter of the table rolls and still be of suiilcient size to be able to resist the pull or tension load created by the wire, and to so locate and arrange the parts that the unsupported length of wire at this point is reduced to a minimum consistent with good operating practice, so that the wire will not sag materially or require a. supplemental support. Further objects will be apparent in the lfollowing disclosure.

In accordance with my invention, I have elimilnated the large diameter roll, usually known as the breast roll, whose top is located in the plane of the wire, and I have provided a return wire roll-or rolls located well below the plane of the wire and entirely remote from the paper laying zone so that this return roll does not in any way interfere with the paper laying operation. In place of that breast roll, I have provided a ilrst table roll of the same, or preferably a somewhat larger size than the other table rolls, which is so located `relative to the second table roll as to provide only a very narrow and straight run of the wire which need not be supported by any further supplemental device. The apron over which the paper stock flows from the head box to the wire is so located as to discharge the stock ontothe wire adjacentv to that rst table roll. The apron is preferably arranged close to and substantially in the plane of the top run of the wire, and the slice is so located that the stockilows smoothly .onto the wire and preferably in a direction which is substantially parallel with the plate of the wire.

Referring to the drawings which illustrate preferred embodiments of this invention:

Fig. 1 is a somewhat diagrammatic side elevational view of the forward end of a Fourdrinier machine having a single large ret roll; and

Fig. 2 is a similar view showing three rolls arranged to return the wire.

The machine shown in Fig. 1 may be so constructed that the top run of the wire I on which the paper stock is irst laid is supported on a, set of closely arranged table rolls I2 suitably carried on bearings mounted on two parallel side bars I4. The table rolls I2 may be oisutable size depending upon the width of the wire, such as 10" in diameter for a wire that is 200" wide. These rolls are located as close together as is required for supporting the wire properly and aiding` in the removal of the water from the pulp carried thereon. The side bars I4 are preferably carried on uprights I5 so arranged that the table rolls may be shaken endwise in accordance with standard practice. The side bars and supports I5 are carried by side frames I6 pivotally mounted at the breast roll end on the pivot bearing lI`I carried by a, standard I8, all of which parts are suitably arranged in accordance with standard practice. The parts may be shaken by a suitable construction, such as that shown in the patents to Kendall et a1. #1,844,580 of February 9, 1932, and Vedder' et al. #1,771,452 of July 29, 1930.

In accordance with my invention, I have replaced the standard breast roll by a small diameter roll which is carried on the ends oi' the two side bars I4 by means of suitable bearing supv ports 2I. This roll 20 may have substantiallyv the same diameter as the table rolls I2, or, as shown in Fig. 1, it may be somewhat larger so as to give adequate support for the wire bending overits surface. 'I'he roll 20, herein termed the iirst roll, is located close to the rst table roll 22, and that distance may be such as to provide substantially the same spacing between the lines of contact of the two rolls with the wire as is had between the second and third rolls and the others of the series. This insures holding the wire substantially in its plane where the stock first ows onto it. To permit this close and equalized spacing, the first roll 20 has a diameter of not substantially greater than twice that of the other table rolls; and its bearing mount is so arranged as to permit it to be mounted close to the next table roll.

The return wire roll 24 is located, in the construction of Fig. 1, on a separate bearing mount 25 carried by the floor or the base of the machine; and provision is made for oscillating this roll the same as are the table rolls oscillated when the wire is shaken. This roll 24 may be of large diameter, such as at least 24 inches, so as not to bend the wire detrimentally as it passes therearound in its return path from the couch roll end of the machine. The roll 24 may be located in any convenient location. It need not be close to the other rolls, since the run of wire between the rolls 20 and 24 does not carry the paper stock. But, as shown, this roll 24 is out of the way and cannot interfere with the bre laying operation. It is best located well beneath the plane of the top run y the same diameter as that of a table roll 48, or

plane of the other two.

having the rigid bottom sliceplate 30, over which the paper pulp stock ows onto the Wire I0, so located that the stock is discharged substantially in the plane of that wire, and preferably at a point which is substantially over the center line of the rst table roll 20 or the first roll which supports the wire in its operative plane. In this construction, a thin flexible slice plate 3| is adjustably mounted, such as is shown in the patent to Vedder, #1,734,929 of November 5, 1929, on the front wall of the head box and arranged to regulate the ow of pulp stock. The slice plate may be bent upwardly and locally by a set of screws 32 pivoted thereto. Each screw is supported by a strut bar 33 and positioned by nut 34 and lock nut 35.

'I'he rigid bottom slice plate 30, which serves as a continuation of the bottom board 35 of the head box, has a thin lip 36 at its forward edge located quite close to aV vertical plane passing through the axis of the roll 20. This is permitted by the small diameter of the-.roll 20; whereas if the roll were of the usual large size of the standard breast roll, this slice lip 36 would have to be located at a considerable distancefrom that plane. The end 31 of the bottom 35 may therefore be made blunt and of thick material of suflicient 'strength and rigidity for the purpose, and yet the thin lip 36 will not project materially Vbeyond the supporting end 31.

Because of this arrangement and the sizes of the parts, the stock may ilow in the plane of the top run of the wire I0.. Also, the stock does not issue ontothe upwardly inclined portion 38 of the wire and so be obli-ged to travel uphill.y As shown in the drawings, this rigid bottom slice plate 30 is substantially tangential to the top of the roll 20. Moreover, the wire between the rst and second table rolls is of such short length that it will not sag materially under the weight of the pulp stock iiowed onto it, and it is not necessary to support the wire on any wire board placed thereunder.

located forward oi4 the table rolls. As shown,

the upper roll 40 may constitute the rst table roll, and the other two are arranged out of the plane of the table roll section of wire.

An intermediate roll 4I takes the most of the bend of fthe wire .and a bottom roll 42 receives the wire as it comes from the couch end of the machine. These three rolls may be suitably mounted, such as on a frame or spider 44 having three arms. In order that the wire may be held taut or loosened, the intermediate roll 4I is mounted for movement relative to Ithe axial This may be accomplished by revolving the spider 44 so as to swing the roll 4I towards the rear. To this end, the spider 44 is pivotally mounted on a bearing support 45 carried by the side frames 46 of the machine. 'I'he top roll 40 may have substantially is preferably somewhat larger, but not materially more than twice the diameter of the table roll. Hence the rst roll 40 may be located close to the adjacenttable roll for the purpose of preventing sag of the wire where the pulp stock issues onto it. The apron 49 is also positioned as described with reference to Fig. 1.

In this construction, the spider 44 may be swung about its axis on pivot 45, in order to slacken the wire and permit itsready removal. That is, when the roll 4l has been moved into the dotted line position or 180 from its normal operative position, the wire at the top of its run is supported on the roll 42 the same as originally carried by roll 40, and the roll 4I has been removed irom contact with the Wire. Thus, I have not only satisfied the requirements as above discussed for preventing any sag in the wire while the stock first flows thereon, but I have also provided a very simple construction which provides for removal of the wire. The rolls 49, 4i and it are mounted on the frame tt and so shake along with the table rolls 4B. The spider may have a revoiuble sleeve t9 eccentrically carrying the pivot shaft 45 which is so arranged that by revolving the sleeve the spider may be lowered somewhat and thus drop the to'p roll til below the plane of the wire and aid in loosening and removing the same. l

The operation of a paper making machine embodying my invention is obvious, in view of the above disclosure.' In each of these constructions, the pulp stock ows onto the top of the rst roll d@ or tt in the table section; vand th'edistance between that rirst roll andthe next table roll is substantially the same as that between any other two adjacent table rolls, so that the wire does not sag materially where the heavy stock rst strikes it. This is made possible by having the first roll tt or dt of a comparatively small size, so that it may be arranged close to the next roll. In some constructions the table rolls are substantially in contact. Hence th'e first rolljshould be small, as compared to the diameters of the others, so as not to spread the supports of the wire at this critical point where the stock flowsl onto it. This is permitted-by having the return wire roll 24 of Fig. 1 arranged at a substantial distance away from the table rolisecticn. This is also permitted in the` construction of Fig. 2 by having the return wire roll 40 in the table section of a comparatively small diameter. The combination of the threey rolls 40. 4I and 42 takes the place of a large return wire roll or breast roll, as is commonly used. The rolls 4| and 42 may also be made of small diameter, since the'wire is bent progressively as it passes around these rolls. These rolls 40, 4I and 42, as well aslrolls 20 and 24 of Fig. 1, have a capillary and drying contact with the wire. A larger numberof return wire rolls may be provided, if desired, 'to eilect a more gradual bending of the wire.l By this arrangemenhI make it possible to have a small return wire roll in the table section and yet not injure the wire by bending it too rapidly.

-It will now be understood that various modifications may be made and equivalent constructions substituted for the parts herein described. Hence. the above disclosure, is to be interpreted as setting forth the principles of this invention and two preferred embodiments thereof and not as imposing limitations on hereto.

I claim: V

1. A Fourdrinier paper making machine comprising table rolls carrying the table section o! the claims appendedgm the wire in substantially a plane, means including shakable side bars for rotatably supporting the rolls in a spaced axially Shaka-ble relationship and providing forv unobstructed drainage therebetween of water passing through the shaking wire, a head box for paper pulp having a. rigid bottom slice plate substantially tangential to the first roll and an adjustable slice plate thereabove arranged for flowing the pulp onto the wire in substantially said plane and in. a regulated flow, a first roll having a diameter of not more than about twice that of a table roll and which is located close to the adjacent first table roll so that they support the wire in substantially said plane under the weight of the pulp, a return wire roll having its front located beneath and forward of the first roll which makes a drying contact with the returning wire and delivers it to the first roll, the discharge edge of said bottom slice plate being located close to the top of said first roll'to cause the stock to issue directly onto the wire substantially over said first roll.

2. A Fourdrinier paper making machine as specified in claim 1 comprising means for adjustably moving the return wire roll to and from normal operating positions without disturbing the rstroll and the table rolls.

.3. A Fourdrinier paper making machine as specified in claim i comprising a movable mount supporting positions for loosening and removal of the wire.

4. A Fourdrinier papermairing machine comprising .means including table rolls for supporting the wire in substantially a plane and providing unobstructed drainage of water passing through the wire, a head box having slice plates arranged for regulatably flowing pulp directly onto the wire, a set oi return wire rolls arranged with their axes in dierent horizontal planes and with the upper roll forming a rlrst roll that supports the wire in substantially said plane in advance of thel irst table roll,` and a revolvable frame supporting the return wire rolls which provides for movement of the rolls to and from their operative wire supporting positions.

o 5. A Fourdinier paper making machine according to claim 4 in which the set of return wire rolls comprises two' rolls having their axes one above the'other and a` third roll located between and forward of the other two and about which the returning wir-echanges in direction and passes towards the table rolls, and wherein the frame is revolvable to move said third roll to a position REFERENCES CITED A V The following references are of record in the.

ille of this patent:

'UNITED STATES PATENTS Number L `Name Date 417,512 Rosquist Dec. 1'1, 1889 1,847,426 Bergstrom Mar. 1, 1932 1,968,028 Clements July 31, 1934 n FOREIGN PATENTS Number Country l Date '1,897 Great Britain 1838

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