US2348340A - Suction roll - Google Patents

Description

y 1944- J. E. GOODWILLIE- ET AL 8,

SUCTION ROLL L Filed Feb. 15, 1941 2 Sheets-Sheet 2 51a.- E'. Baez).

- the roll and the barrier.

Patented May-9, 1944 UNITED STATES PATENT OFFICE SUCTION ROLL John E. Goodwillie and Earl E. Berry, Beloit, wn, assignors to Beloit Iron Works, Beloit, Win, a corporation of Wisconsin Application February 13, 1941, Serial No. 378,712

8 Claims.

This invention relates to suction rolls especially adapted for use in inverted position with the suction area in the lower half of the roll.

More specifically, the invention relates to the confinement of the air and water mixture drawn in through the holes of the perforated shell of a suction roll between the inside surface of the shell and a surface of the stationary suction box so as to maintain substantially uniform and moderately, high velocity flow until the mixture is released in the interior of the suction box, thereby preventing remoistening of the felt and web acted on by the roll.

In the usual suction roll, the air and water mixture drawn in .through the perforations of the revolving roll shell as these perforations pass the suction area is allowed to fall through an unimpeded passage into 'the stationary suction box within the shell. Now, if the suction box opens downwardly instead of upwardly and the suction area is in the bottom half portion of the roll, the velocity of the water and air mixture will materially decrease as soon as the mixture is freed from the perforations or holes in the shell. A high vacuum must be maintained to prevent the water droplets from again falling back into the holes and thus remoistening the felt and web. As a result, the use of suction rolls with suction areas in the lower half portion of the roll has always heretofore required high capacity vacuum pumps in order to mainform of barrier is a closed box mounted in the opening to the suction box and extendin from the suction box into spaced relation with the interior of the shell. The surface of this closed box which is adjacent to the shell is in diverging relation with the shell and thus defines a, confined passage which increases in height from the oncoming to the offgoing seal end thereof. A side wall of this box adjacent to the ofi'going seal can cooperate with this seal and seal head as well as with the adjacent wall of the suction box to define a confined passage leading to the interior of the suction box.

It is, then, an object of this invention to provide a suction roll capable of being used with the suction box in an inverted position without necessitating the use of a high capacity vacuum pump and without increasing the power cost over the amount required for operation of a suction roll with the suction box opening in an upward direction.

A further object of this invention is to proflow of the air and water mixture to a point in tain a high velocity flow of the water and air mixture drawn through the perforations in the shell, even after this mixture was freed from the shell.

In accordance with the present invention, however, the necessity for such high capacity vacuum pumps and the increased cost of operating such pumps has been avoided by providing a restricted 'path for the air and water mixture from the time it leaves the perforations in the shell until it is discharged to a point in the interior of the suction box where it cannot flow back into the shell. I

In a preferred embodiment/of the invention the restricted path is created by mounting .a barrier in the suction area in spaced relation from the shell of the roll. A restricted pass ge is thus formed between the inner surface of This passage communicates with another restricted passage adjacent the offgoing seal of the suction box and leading to the interior of the suction box at a point where the discharge of the water and air mixture cannot reach the roll. A convenient tween the seals which passage increases in height from the oncoming seal to the ongoing seal.

Another object of this invention is to provide a suction roll with a suction area in the bottom half portion thereof which is equipped to prevent gravity drainage of water back to the shell of the roll.

Another object of the invention is to provide a wall between the seals of a suction roll which is closely adjacent to the roll shell at the oncoming seal and which diverges from the roll shell as it approaches the ofigoing seal.

Other and further objects of the invention will be apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which, by way of example, show two preferred embodiments of the invention, It will be understood, however, that parts omitted.

Figure i is a fragmentary transverse crosssectional view similar to Figure 3- but illustrating a modified'embodiment of the invention.

As shown on the drawings:

In Figures 1 to 3 inclusive the reference nu-' meral I designates generally a suction roll according to one embodiment of the invention. The suction roll It includes a stationary suction box having hollow trunnions |2 at the ends thereof around which are rotatably mounted the end heads l3 of the perforated roll shell ll. The

, heads |3- have sleeve portions |3a projecting therefrom and adapted to be rotatably mounted in supporting bearings for theroll (not shown).

One of the trunnions |2 has openings |2a therethrough communicating .with the interior of a housing l6 which is connected to a suction conduit-l8. I

Both trunnions l2 have the ends thereof closed with caps.

The suction box H has a longitudinal slot or opening It in the bottom portion thereof bounded by a flange IS.

The slot l8 terminates short of the ends of the suction box H as best-shown in Figure 1 and flat decks 2|) continue longitudinally from the end flanges I8. These decks 20 are cast integral with the suction box and can be covered with L smooth wear plate 20a if desired.

As best shown in Figure 3, the suction box II is built up on the longitudinal sides of the opening It to provide longitudinal heads 2|. These heads have wells or grooves 2|a therein openof the hangers 23 so that the seals will be sussuction area, although an adiustablelongitudinal ing at the bottoms thereof and receiving suspension springs 22 therein. The suspension springs are mounted on hangers 28 carried by the heads 2| and the bottom ends of the springs are encased in cups 24 slidably mounted in the wells or grooves 2|a. Hangers 25 are secured to the lower ends of the springs 22 and extend through the cups 24 for carrying longitudinal seal mountlugs 26. These seal mountings 26 are in floating relation relative 'to the suction box II and carry longitudinal seals 21 engaging the inner surface ofthe shell it. The springs 22 are regulated to suspend the mountings 26 so that the seals 21 1 will just engage the shell M to eflect a sealing 'without undue rubbingagainst the shell.

The seal mountings 28 are in sealing relation with the heads 2| in all operative positions of the mounting. This sealing is efl'ected by means of a small rod or wire 28 between adjoining tapered surfaces of the mounting and heads. The rods are held in place by means of spring clips 29 carried by the heads. can rise and fall relative to the heads, but the Thus the mountings seal mounting could be used without departing from the principles of this invention. In accordance with this invention a closed hollow box 3| is bolted or otherwise fixed on the flange l9 and extends between the seal mount ings into close proximity with the inside surface of the shell M. The wall 3| a of the box adjacent'to the shell IA, as best shown in Figure 3, is quite close 'to the shell at the end thereof next to the oncoming seal and then diverges into greater spaced relation from the shell at the off going seal end thereof. The wall 3|a has a smooth regular contour and is preferably spaced from one-eighth inch to one-quarter inch from the shell at the oncoming seal while it may be spaced from one-half inch to three inches from the shell at the ofigoing seal end thereof;

A restricted passage A is thus formed between the wall am and the shell l4 and this passage increases in height from the oncoming to the oil going seal ends thereof. A side wall 3Ib of the box cooperates with'the offgoing seal mounting 26 andithe adjacent head 2| of the suction box to provide an upwardly extending passageway B communicating with the passageway A between the shell and wall 3|a. a The flange IQ of the suction box is apertured as at l9a. A plurality of individual slots or apertures |9a can be provided along the length of the flange as shown in Figure 2, or a single long slot can be used.

This same flange I9 carries a shield device 32 providing a passageway C communicating with the passageway B, and extending into the interior of the suction box. The shield device 32 is composed of a plate 33 bolted to the flange 9 as at 34 and to the end walls of the suction box H as at 35-. The plate 33 has end flanges such as 33a carrying another shield plate 36 which extends from the head portion 2| of the suction box to the top of the box as best shown in Figure 3. The plate 83 terminates at a central portion of the suction box The communicating passageways A, B and C thus provide a restricted or confined path for the flow of airand water drawn from the web and felt W and F passing under the roll as shown in Figure 3. This restricted path maintains a high velocity flow for the air and water mixture and the velocity of this mixture is not killed un-' til the mixture is discharged into the main interior of the suction box II at a point where it cannot flow back to the shell.

wire 28 will always be urged into engagement with the adjoining tapered surfaces to prevent As illustrated in Figure 3. the felt F and web W cover the suction area between the seals 21 and travel'with the shell I 4 in the direction indicated by the arrow. The first hole in the shell clearing the oncoming seal will be subjected to vacuum existing in the passage A and it will be evacuated so that as the holes advance toward the oflgoing seal 21, air and water will be drawn therethrough and will discharge into the passageway A. This air and water mixture will thus be drawn up' through the passageways B and C and discharge into the interior of the suction box H at the upper end of the plate 33.

- from through the end walls of the box 3| and on the shanks of the hand wheels 42 have difierent pitches so that a rotation of the hand wheels will effect a longitudinal shifting of therods I to tilt the levers 39 and thus move the seals 30 toward and away from each other.

Flexible rubber or leather housings 43 can be secured on the box 3| and surround the levers 39 for preventing drainage of water into the interior of the box.

From the above descriptions it will therefore he understood that this invention now provides for the mounting of a barrier in the suction slot of a suction box for cooperating with the perforated shell of a suction roll to provide a restricted passageway communicating with the interior of the suction box for maintaining a high velocity flow of materials drawn out of the holes in the shell. This barrier prevents remoistening of the webor felt passing under the suction area of the roll and the suction rolls of this invention are especially adapted for operation with their suction areas in the lower portion of the roll.

In the modified suction roll Illa shown in Fi ure 4 parts identical with parts described in Figures 1 to 3 have been marked with the same reference numerals. In the roll Ina, however, a box 5!! of a different shape than thebox 3|, is mounted on the flange l9 and cooperates with a modified ofigoing seal 5| and seal mountin 52 to provide a more regular restricted path to the shield device 32. Thus the bottom wall 50a of the box 5| diverges from the shell I as it approaches the oifgoing seal 5|, but the side wall 501) of the box has an outwardly bowed curved corner 590015 the samecontouras the inner face 5la, of the seal 5|. Likewise the seal mounting 52 has an inner face 520. curved to form a continuation of the curvature of the face 5la. As a result the passageway B is free from abrupt shoulders and merges smoothly into the passageway A as well as into the passageway C. The airand water mixture drawn through the perforations of the shell, thus -flows along a smooth confined path to the interior of the suction box. The seal 5! gradually curves away from the shell H as shown, thereby eliminating'a corner or pocket such as occursin the structure shown in Figure 3.

It will, of course, be understood that various details of the invention may be varied through a. wide range without departing from the principles of the invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

We claim as our invention:

1. A suction roll comprising a longitudinally slotted suction box having an outturned head on each side of the slot and flanges projecting inwardly from said heads to define the periphery of the slot, seals floatingly carried by said heads outwardly of said flanges, a perforated shell rotatably mounted around said box in sealing engagement with said seals, a closed hollow box bridging said slot and secured to said flanges, said box having side walls extending between said seals and a bottom wall in closely spaced relation to said shell, one of said flanges having an opening therethro'ugh, a shield member mounted on said flange and defining a passageway communicating with said opening, and said shield member extending to the central portion of said suction box, whereby said hollow box and said shield member cooperate with said shell and an adjacent seal to define a confined path for maintaining a high velocity flow of materials drawn through the shell until said materials are released in the interior of the suction box. v

2. A suction roll comprising a suction box having spaced parallel outturned head portions, a flange extending inwardly from said head portions and defining a longitudinal opening for said box, suction seals floatingly mounted on said head portions, a perforated shell rotatably mounted around said suction box in sealing engagement with said seals; a closed hollow box secured to said flanges and bridging said opening, saidbox having side walls in spaced relation from said seals and a bottom wall in closely spaced relation to said shell, a shield member secured to said flange on one side of said opening defining a passageway to the central portion of the suction box, and said flange having an opening therethrough communicating with, said passageway wherebygan evacuation of said sucbox and the adjacent seal and said shield member.

3. A suction roll comprising a stationary suc- 7 tion box having downwardly extending head portions with .open bottom chambers therein, an inturned flange between said head portions defining the periphery of a longitudinal slot in said suetion box, springs suspended in said chambers of the heads, seal mountings carried by said springs,

" seals on said'seal mountings in sealing engagement with said shell, aclosed hollow box secured on said flange having side walls extending between said seals and seal mountings in spaced relation therefrom and a bottom wall in closely spaced relation from said shell, and said flange having an opening therethrough joining the space between a side wall of the box and the adjacent seal with the interior of the suction box.

4. In a suction roll including a perforated rotatably mounted shell, a stationary suction box in said shell, a longitudinal oncoming seal between said shell and suction box, and an offgoing longitudinal seal between said shell and said suction box, said seals defining a localized suction area .on said shell, the improvements which comprise a barrier wall in said suction area spaced fromone-eighth to one-quarter inch fromsaid shell at the oncoming seal and spaced from onehalf inch to three inches from said shell at the ofigoing seal end thereof, and means defining a passageway to the interior of the suction box ad- I jacent said ofigoing seal communicating with the space between the barrier wall and shell.

5. In a suction roll including a suction box, a perforated shell rotatably mounted therearound, and seals including clfgoing and oncoming seals between the shell and box defining a localized suction area on the shell, the improvement of a wall between said seals extending from adjacent the oncoming seal across said suction area to terminate in spaced relation from the oilgoing seal, said wall being spaced inwardly from said shell in diverging relation thereto to define a confined path increasing in capacity as it approaches the offgoing seal and communicating at its point of greatest capacity with the interior of the suction box.

6. A suction roll comprising a suction box having spaced opposed longitudinal heads depending therefrom, an oncoming seal supported on one head, an ofigoing seal supported on the other head, said box having a longitudinal slot defined by a flange between said heads, a drain outlet at the end of said box, a liquid-pervious cylinder rotatable around said box and cooperating with said seals, a member mounted on said flange having side walls between said heads and seals and a bottom wall closely adjacent the cylinder at the incoming seal and diverging away from the cylinder toward the ofigoing seal to cooperate with l the cylinder for defining a restricted flow path, "said side wall adjacent the otfgoing seal being spaced from the seal and the head carrying the seal to define a passage communicating with the path, a conduit mounted in the box on the flange adjacent the oifgoing seal carrying head, said conduit having a lower-inlet end communicating with said passage, and said conduit having an upper discharge end in the box at a level above the bottom of the drain outlet.

' 7. A suction rollcomprising a suction box'having spaced opposed longitudinal heads depending therefrom, said box having a longitudinal slot defined by a flange between said heads, an onin spaced relation from the concave inner face coming seal mounting suspended from one head, an oflgoing seal mounting suspended from the other head, said offgoing seal mounting having a concave inner face, a perforated cylinder rotatable around said box, seals on the seal mountings cooperating with said cylinder to define a suction area thereon, a member mounted on said fiange having side walls between said heads and seal mountings and a bottom wall closelyadjacent the cylinder at the oncoming seal end thereof and diverging away from the cylinder'toward the oflgoing seal end thereof to define a restricted flow path, said member having a convex portion of the oflgoing seal mounting to cooperate therewith for defining a discharge passage for said path, and means connecting said passage with the interior oi the box.

v 8. A suction roll comprising a suction box having spaced opposed seal' carrying longitudinal heads depending therefrom, said box having a longitudinal slot defined by a flat flange between said heads, said suction box having fiat decks between said heads at the ends of said slot, a hollow barrier box having a top wall mounted on said flange, side walls depending from said top wall between said heads, end walls between said decks,

and a bottom wall providing a barrier, a perfobarrier box, means for tilting said leversgand connecting links between said levers and said end seals extending through the end walls of the barrier 'box whereby tilting of said levers will shift the end seals to vary the length of the suction area.

JOHN E. GOODWILLIE. EARL E. BERRY.

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