US2165549A - Paper machine suction slice - Google Patents

Description

y 11, 1939- L. HORNBOSTEL 2,l65,549

PAPER MACHINE SUCTION SLICE Filed Nov. 29, 1935 2 Sheets-Sheet 1 July 11, 1939.

LHORNBOSTEL PAPER MACHINE SUGTION SLIGE Filed Nov. 29, 1935 2 Sheets-Sheet 2 ?atentati 'July ll, 1939 UNITED ,STATES 2. ,9 Pm MACHINE SUCTON suo Lion ombotel, Beloit, Wie., Iron orks Belolt.- Wi., mein igor to me a comratio or wis- Application November za, 1935, se No. 52,132

This invention relates to paper machines and has special reference' to' improved slice mechanism !or removing the water pressed !rom the top oi' a sheet or web at the nip of two rolis.

As iswell known to those skilled in the art,

^ there are numerous places in ,the processes o! making paper where water is squeezed out oi the sheet or the !elts by being passed between two rolis. Normally no dimculty is encountered in disposing of the water which flows out from the bottom oi the telt or sheet, but the water that is squeezed out of the top tends to build up at the nip oi the rolis, frequently assuming considerable proportions at these points and nflowing of! the edges of the felt or sheet adjacent the ends oi the rolis. Even in a suction roll where the object is to draw all or a large part oi' the water through the roll shell, in most instances the resistance of the sheet is such as to cause a pond oi water to form on the top oi the sheet or felt. This water must then flow back on the felt or paraliel to the roll and over the edge of the felt. It is also sometimes necessary to use a board. called a slice board, which drags on the felt to keep the water irom running back and soaking into the felt and sheet. Where the water flows in a 'direction crosswise of the sheet or telt and outwardly from the center oi the machine, there is necessarily a deeper pondat the center than at the edges. This produces a lack of uniformity across the width of the sheet, particularly affecting the edges o! the sheet which retain a considerable amount of moisture so that the edges of the sheet are not uniform with the center portions o! the sheet. Nume'ous devices have been employed in an attempt to remedy this condition, but so far as I am aware, none of these have been entirely satisiactory'. According to my invention, I propose to suck this water up uniformly along the nip and in close proximity to the nip.

An important object of the invention is the provision of a generally improved paper machine slice.

I have also aimed to provide a slice lip of improved structure and improved means !or holding the lip.

Another object of the invention is the provision o! a paper machine slice having no appreciable pressure on the felt, thus substantially eliminating-wear on the felt from this source', and saving power.

- A further object oi the invention is the provision: of a paper machine slice which picka up the water across the entire width oi the sheet as 'soon as it is freed !rom the felt to maintain a uniiorm moisture condition across the sheet.

Another object is the provision of a paper machine slice having means tor cleaning the same without disturbing the setting thereoi.

A more specific object of the invention is the provision o! a paper machine suction slice ot a construction such as to substantially eliminate the danger associated with the 'proper setting thereot, and wherein the adiustment o! the slice 0 is materially simplified. 'I have also ained to provide means for removing the excess ot free water at the edges` of the felt beyond the edges of the sheet.

Other objects and attendant advantages will become apparent to those skiiled in the art from the following description and the accompanying drawings, in which-- Figure 1 is a section through a suction slice embodying my invention showing the manner 20 ot positioning the slice with respect to the rolis of a cylinder machine;

. Fig. 2 is a. section transversely through the suction box and slice lip;

Fig. 3 is a iragmentary top view of the suction box and slice lip, one end of the suction box being shown in section;

Figs. 4 and 5 are i'ragmentary 'cross-sections showing bona nde forms of the outer edge of the slice lip; 30

Fig. 6 is a iragmentary section through the slice lip taken at right angies to Fig. 2;

.Fig. 'l is a iragmentary top view o! the suction slice as applied to a suction roll, and

Fig. 8 is a side view of the form shown in Fis. 7.

Referring first to Figs. 1 to 6 inclusive, the numer-als ll, II, I: and M designate re'spectively a cylinder mold, an end of the vat in which the cylinder mold rotates, a couch roll operating thereagainst, and a felt passing between the cylinder mold and the couch' roll. It will be understood that this particular arrangement of parts is merely for the purpose o! illustrating the invention and that the slice is adapted for use in conjunction with any pair oi rolis where water tends to build up on the top-of a felt or. sheet passing therebetween. such a situation frequently develops between press rolls, particularly primary press rolis, at suction rolls as shown in Figs. 'I and 8, at extractor rolis and the like. Frequently the sheet passes between the rolls with a felt on both its upper and lower sides and oc'casionally otherwise, and it is not intended to limit the invention to the particular combination o! rolls or the manner in which the sheet is passed through the rolls.

In this particular instance wherein the wholLv or partially formed sheet and a felt pass between the' cylinder mold ll and couoh roll !3, a large amount of water is pressed from the sheet and the ielt, and tends to build up on top of the felt in the wedge-shaped area |5 adjacent the line of contact. As previously noted, this water tends to flow lengthwise of the roll and across the sheet, running oi! the felt at the edges. However, this does not run oil' rapidly enough to prevent a considerable head of water from existing Just ahead of the couch roll.

In order to avoid the condition above described, I provide a lip designated generally by the numerai- 56, in this instance formed of soft rubber and being in sheeted or strip form as shown in Fig. 6, the lip having a plurality oi' closely spaced parallelly disposed channels i? terminating along the edges of the strip or lip. This lip extends the full width oi' the web and it will be understood may take a number of forms, as, for example, short sections vulcanized or otherwise fastened together. It may take the form of a pluralty of tubes, or may be of a single piece depending upon the ease of manufacture or the desires of the manufacturer. It will likewise be seen that while it is convenient to make the lip of soft rubber, other materials, such as fabric, may in some instances be used. the important factors being that the lip be resiient to allow passage through the rolls without damage and that the walls have sumcient strength to prevent Collapse of the channels under the suction of which about two to three inches of mercury is normally sufllcient. One edge of the lip is clamped in a suction box designated generally by the numeral s, which in this instance is of tubular form having an opening s along its side for reception of one edge of the lip s, the opening being deflned by jaws 2! and 22. spaced bolts 23 pass through the jaws and serve to tighten the jaws to frictionaly grip the edge of the lip as shown in Fig. 2. The suction box and lip is preferabiy formed by a drawing operation, the suction box being drawn in the required shape and in suitable lengths. End pieces 24 and 25 (Fig. 3) are positioned in the ends of the suction box and secured therein by means of screws 26 and 21 which pass into sleeve portions 28 and 29. The end pieces also have shoulders 3| and 32 which abut against the end of the tubular body portion of the suction box and which projectoutwardly as shown at 33 and 34 to close the ends of the opening IS between the jaws. The end pieces have axially extending hublike portions 35 and 36 adapted to function in supporting the suction box as will presently appear. The end piece 25 has a cross piece 31 closing the end of the suction box while this cross piece is absent in the end piece 24. The outer end of i the end piece 24 is threaded as shown at 38 for the attachment thereto of a pipe or other conduit connected to suitable pumps for the purpose of applying suction to the box.

In the example shown in Figure 1 the suction box is supported on the ends of the vat I 2 through brackets 39 on opposite ends of the vat, these brackets having sleeves 4| within which rods 42 are slidably received, the rods being held in adjusted positions by means of set screws 43. The rods 42 carry saddles 44 which are provided with set screws 45, the saddles 44 receiving the portions 35 and 36 of the end pieces 24 and 25 of the suction box to support the same-in its operative position. The set screw 45 serves to secure the suction box in a desired rotative position to regulate the elevation or angularity of the lip !5.

The suction box extends the full width of the machine so as to hold the outer edge or the-lip |6 adjacent the nip of the rolls throughout the entire width of the sheet or web passing therebtween. The inner edge 46 of the lip 16 is ciamped between the jaws 2! and 22 by means or the' bolts 23. These bolts are spaced longitudinally of the jaws and are screwed down until the lip is firmly gripped between the jaws without materially distorting or fiattening the channels H. Cioth backing strips 41 and 48 are cemented onto the opposed surfaces of the lip adjacent the edge 46 to provide a suitable gripping medium for the jaws. This arrangement serves to hold the lip in the suction box during any normal operation oi the device. The free or outer edge of the lip 6 may take a number of shapes depending upon the conditions of installation, such, ior example, as the shapes shown in Flgs. 2, 4 and 5. Means may also and preferably will be provided for the purpose of ushing out or cleaning the channels l'i in the lip within which puip and other solids will sometimes build up so as to reduce the eihciency of the slice. such means will be described in connection with Figs. 7 and 8.

In Figs. 7 and 8 I have shown a different manner of mounting the slice, such as will preferabiy be used with a suction roll wherein the numeral 49 designates generaliy the suction roil and the numeral 5| a top pressure roll operating thereagainst carried in bearings 52 having arms 53 through which pressure is applied to the roll through rods 54 in a well known manner. In this instance brackets 55 are attached to arms 53 at opposite ends of the rolls, the brackets corresponding in function to the brackets 39, being, however, diiferently shaped. These brackets have sleeves 56 for the reception of the rods 42 to support the saddles 44 which in turn support the suction box' as previously described. In this instance it will be noted that the' brackets 55 being carried on the arms 53 cause the suction box alnd slice lip to move with the top pressure roli 5 In this instance suction is applied to the suction box through a pipe 51 attached to the rear side of the suction boxwhich in turn is connected to a pipe 58 from the usual suction pumps through a flexibie hose 59, valve 6i, T 62, and conventional fittings, the flexibie hose 59 permitting movement of the suction box. A pipe 63 is connected into the T 62 and 'serves to admit fluid for the purpose of flushing out the lip and suction box. For this purpose the valve 6I to the suction pump is closed oil' and the valve 64 in the line 63 is opened so that fluid such, tor example, as water, ma be admitted filling the suction box and causin'n outward flow through the channel l'l so as to flush out the suction box and slice lip. It will be seen that this is accomplished without in any way disturbing the adjustment or setting of the slice. The water flowing out through the passages i'i inthe lip or clear the passages of foreign matter, such as paper fiber, dirt and nap from the felts, which may collect and retard the action of the slice. This flushing operation may take place while the machine is in operation without only momentary loss oi' the advantage of the suction slice. As previously mentioned, it

is contemplated that when the slice is used on a cylinder mold as shown in Figs. 1 and 3, a similar arrangement is used to Permit fresh water to be introduced into the suction box tor the purpose of flushing out the same.

In operation, the slice is positioned on the paper machine in the position shown in Figure 1 and is adjusted by means of the set screws 43 and 45 so that the forward edge of the lip rests in close proximity to the nip of the rolls. By use of the set'screws 45 the slice may be adjusted so that either the lip is free of the felt or so that it rests lightly on the felt, depending upon the particular requirements. At all events it will be seen that the slice may be adjusted so that the forward edge of the lip is in close proximity to the point at which the liquid is expelled from the felt or sheet. The Capacity of the channels l'l and of the suction device may advantageously be greater than that required to remove the water so that it is drawn in from the surrounding spaces. In this manner the fluid along the edges of the felt in the sheets is drawn up and inward; that is, slightly toward the center of the sheet, and as a result, the sheet passes through the rolls with the edges thereof of substantially the same dryness as the remainder of the sheet, thereby preventing crushed edges due to the excess of water at this point.

One of the reasons in the past for an excess of moisture along the edges of the sheet is that the distance between the rolls is the thickness of sheet and felt combined, whereas the sheet is narrower than the felt or felts, thereby leaving a strip of lesser thickness along each edge from which the water is incompletely expressed. After the sheet and felt have passed through the rolls the excess water in the edge strips rapidly works back into the edge of the sheet by capillarity. This action is substantially entirely avoided by the use of the present invention.

It will be noted that since the lip is formed of rubber or other resilient material it may be permitted to drag lightly on the felt so that it is automatically adjusted as to height, and so that the drag occasioned by the usual slice board is eliminated, thereby eliminating the power load and the wear on the felt associated therewith. Another important feature of the invention is the fact that the lip may be set very close to the nip without the danger of damage to the equip ment or injury to the operator. It will be understood by those skilled in the art that in the setting of a slice wherein it is necessary to adjust the posiiton of parts in close proximity to the nip of rapidly moving rolls there is always danger that the slice will be caught between the rolls and drawn through. If the slice is of rigid material when this type of accident occurs, severe damage is done to the equipment and there is grave danger that the Workman in the act of adjusting the slice may be drawn into the rolls and seriously injured. With the present invention it will be seen that the lip is formed of resilient material and is clamped in the suction box. consequently, should the forward edge of the lip catch in the nip and be drawn through the rolls, no material damage is done, since the lip itself is formed of resilient material which may readily pass through the rolls and the connection between the lip and the suction box is such that this excessive force causes the lip to be drawn out of the suction box without damage to the latter and without any danger that the workman who is holding or adjusting the suction box will be drawn into the rolls and injured. Because of this safety feature it is possible for the slice to be adjusted within much closer limits than Search has heretofore been possible `since the operator can afford to take much greater chances on the lip being caught between the rolls. Therefore, important structural features of the device are the use of a lip of resilient material which is frietionally or otherwise held in the suction box so that the lip will slip out of the box if caught by the rolls and will pass through the rolls without damage. Another advantage of importance is the improved quality and uniformity of the sheet caused by the uniform removal of the water therefrom.

While I have thus described and illustrated a specific embodiment of my invention, I am aware that numerous alterations and changes may be made therein, and I do not wish to be limited except as required by the prior art and the scope of the appencted claims, in which- I claim:

1. The combination in a suction slice of a suction box having means for gripping a lip to normally hold the lip in position and releasing the lip when caught between said rolls, and a resilient lip of such compressibility throughout as to be capable of passing between opposed paper machine rolls without damage thereto, said lip having a plurality of channels terminating at one end within the suction box and at the other end terminating at a remote point outside said box to draw water into the suction box from adjacent the nip of paper machine rolls.

2. A paper machine slice comprising in combination a suction box, and a slice lip frictionally heldin said box along one edge, said lip comprising a sheet of soft rubber having a plurality of parallelly disposed bores extending from edge to edge thereof.

3. A suction slice for removing the water at the nip of paper machine rolls comprising a suction box of substantially the length of said rolls, said box having a pair of spaced jaws extending substantially the length of the box and defining a slot in said box, and a slice lip of resilient material clamped between said jaws with a force suficient to normally retain the same therein but permit withdrawal when the strip is caught between the rolls, said lip having a plurality of channels spaced longitudinally of the box terminating at one end in the box and at the other end adjacent the nip of said rolls to remove the water from the nip by suction therethrough, and means for adjusting the clamping action of the jaws on the lip to predetermine the force required to pull the lip from between the jaws.

4. A suction slice for removing the water at the nip of paper machine rolls comprising a suction box of substantially the length of said rolls, said box having a pair of spaced jaws extending substantially the length of the box and defining a slot in said box, and a slice lip comprising a sheet of soft rubber clamped along one edge between said jaws, said sheet having a plurality of channels spaced longitudinally of the sheet, one end of said channels terminating in said box and the other end terminating at the opposite edge of the sheet adjacent the nip of said rolls to remove water from the nip through said channels. i

5. The combination with a paper making machine of a suction slice comprising a suction box extending transversely across said machine adjacent a pair of rolls, a slice lip carried therein releasable under an excessive pull and comprising a sheet of resilient material Secured along one edge in said suction box and having a plu- Room rality of channels extending from edge to edge thereof, said sheet being of such resiliency as to pass through the rolls without damage thereto, a yoke supported on each side of said machine for supporting said suction box to support the lip in close proximity to the nip of the rolls, said yokes being adjustable toward and away from said rolls to position said suction box, and means acting between said yokes and said suction box to predetermine the angular position of the latter.

6. The combination with a. paper making machine having a pair of rotatable rolis and means for supporting one of said rolls for lateral movement of a suction slice comprising a suction box extending across said machine adjacent said roils, a resiiient slice lip carried therein for removing water from the nip of said roils, means for supporting the lip on the box for release under an excessive pull, said lip comprising a sheet of resiiient material Secured along one edge in said suction box and having a plurality of channels extending from edge to edge thereof, said sheet being of such resiiency as to pass through the rolls without damage therto, means tor supporting said suction box on said roli supporting means for movement therewith to support the lip in close proximity to the nip of the roils, and means for predetermining the position of the lip with respect to the nip of said rolls. I

7. A suction slice lip comprising a sheet of resilient material having a piuraiity of paralielly a disposed channels extending from edge to edge thereof, and means on opposite sides of the sheet ,adjacent one edge providing gripping surfaces

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