US1814050A - Suction roll - Google Patents

Description

July 14, 1931. M X 1,814,050

SUCTION ROLL Filed. Sept. 9, 1929 fiderl War-2 Patented July 14, 1931 PATENT OFFICE ROBERT JOSEPH MARX, 01 LONDON, ENGLAND SUCTION ROLL Application fled September 9, 1988, Serial No. 891,284, and in Great Britain April 8, 1929.

This invention relates to improvements in suction rolls of the type in which a perforated shell revolves around a fixed sucto prevent undue leakages of air, which, in

decreasing the vacuum, efliciency of the apparatus.

Various means have hitherto been employed for effecting this stance, it has been propose to employ a revolving shell within which the suction box is located, and to cause the suction box to be $0 pressed against the revolving shell. Again, where the suction box is fixed at adistance from the rotatin shell, contact between the two is establishe by movable packing strips which are actuated by water-or spring pres sure or similar means with the above object. All these methods have disadvantages.

Where the suction box is pressed against the shell, the pressure set up involves a larger consumption of power; wear and tear is increased, and constant adjustment of the pressure is indispensable. Where moving packing strips are provided they are liable to seize, thereby preventing the movement necessary for adjustment, while the means for inducing the pressure require repair or renewal, and the strips themselves need to be adjusted or replaced from time to time. There are other defects inherent in these methods, which will be more readily apprehended if it is remembered that paper machines are sometimes of a working width kewise decrease the up to 20 feet, in which case the packing devices protecting the zone of suction or vacuum extend over twice 20 feet in the cross direction of the paper machine and over twice the breadth of the suction box. In all cases the suction space which has to be packed to exclude undue access of air may be represented by a rectangle, measuring on two sides a little more than the work (purpose; for in-,

ing width of the machine and on the two ends twice the width of the suction area.

My invention consists in providing the open u'pper edges of the suction box in the direction of the longer axis of the shell with outwardly extending lips, the upper surface whereof in cross section conforms to the contour of the inner surface of the shell, which lips extend circumferentially over a suflicient distance to cover several rows of perforations in the shell, the shell being so supported 'on its bearings as to bear on such lips with an eas running fit but without intentionally in need pressure.

In carrying out my invention which lends itself to var1ous methods of application, I employ preferably radially stationary suction box of suitable metal, such as cast iron or steel,'having an open top, which constitutes the suction or vacuum area. The box 7 is mounted within the perforated revolving cylindrical shell, and is adapted, by any suitable means, to be so circumferentially adjusted as to apply the suction at an desired part of the periphery of the revo ving shell, but in other respects is in fixed relation to the shell. a

The revolving shell is maintained in a fixed position relatively to the suction box by being revolubly mounted on fixed journal bearings, of any suitable type. It may convenientlybe made of brass, bronze or other suitable metal, and is referably carefull balanced so as to enab c it to run for al practical purposes truly circular at the requisite speed of the paper machine on which it is employed, and to assist in insuring the maintenance of the shell and the suction box in their proper relative positions, the walls of the suction box are rovided o'utwardl with ribs or the like against which the shell can bear. The upper edges of the sides of the suction box are provided along their entire length with lips, the upper surface whereof in cross section is struck to the same radius as the internal circumference of the shell and is of suflicient width circumfe'rentially to cover several rows of perforations in the shell, by preference not less than four or five rows. The internal shell 1 surface is machined to a true easy sliding' fit over the lips of the suction box walls,

and is so mounted on its bearings as to re- 'volve with a sliding fit thereon.

The outwardly extending lips may be inseparably attached to the suction box or made detachable therefrom.

I find that the construction and arrangement of these two lip members above described constitute in effect a sufiicient packing across the length of the 'face of the suction roll on both sides of the box to prevent undue leakage.

The bearing surfaces of the two lips of the suction chamber being wide, the friction between the machined revolving shell and the stationary suction box lips becomes negligible as far as wear and tear isconcerned, even in cases where a high vacuum is maintained-in the suction box. V i

I may also provide for the'insertion of a packlng stri each side of the ox below the lips contacting with the inner surface of the shell, although generall speaking, the intersection of the lips wit the shell as above described is in itself suflicient without the use of such strips.

The ends of the suction space are packed by suitably shaped anti-friction strips held in contact with the revolving shell by light spring pressure, or other suitable means.

By the reduction of the number of working parts in a suction roll my invention also facilitates the cleaning of the apparatus, it permits the easier removal of fibres from the inside of the roll and particularly the washing up. when changing the color of paper made.

In order to free the internal parts more easily and completely from traces of dye and fibers, I provide the external ribs of the suction box with open slots through which the traces of fibres and dyes pass outwith the washing water.

My invention is illustrated in the accompanying drawings, in which Figure 1 is a half part longitudinal section on the line w-m of Figure 2 and a half part longitudinal elevation.

Figure 2representsa cross section on line Y-Y through the roll, and

-Fig'ure 3 is a detail view on an enlarged scale.

In all the figures like reference letters denote the same parts.

In Figure 2 A represents the perforated revolving cylindrical shell, B the suction box, C the suction opening, D the ribs 01. the suction box, E outwardly extended lips or flanges on the edges of the sides of the suction box over the entire length of the suction or vacuum area, F the rubber strips, G the means of securing them in place, and J the open slots in the ribs through whlch 1mof rubber or the like on verse external ribs.

In Figure 1 H denotes the end paclcings .which are adjustable from both sides to ermit making sheets of diflt'erentwidths. or board machines or others on which only one width of sheet is produced, the end packings can be made as fixtures.

Several shallow grooves or notches K are arranged over the entire length of the uper surfaces of the outwardly extended lips of the suction box B, as shown in Figure 3.

These grooves are'by the operation of the suction roll continuously kept full of water. The perforated revolving cylindrical shell continuously takes along a small quantity of water from these grooves which remains suspended as a water film on the solid part of the internal circumference of the shell so as to-serve as an. additional packing medium between the rota revolvin shell and the outwardly extende' lips of t e suction box.

so as not to restrict the invention to themethod of application shown in the draw- Vith' respect to the function of the longitudinally extending outwardly dis osed ,rigid or fixed lips E, it is to be note that they actually constitute the only length packing between the box and the revolving shell and are the only protection against access of air to the area under suction. The fixed non-movable un ielding lips E are so placed and shaped as ereinbefore described that they make constant contact with the revolvin shell. Although the fixed lips are the on yv protection against access of air to the suction area, the feature which makes the ingress of air at this position impossible is the thin film of water which with my construction must adhere to the internal circumference of the shell, and which co-acts with the thin film of water on the fixed lips.

These two water films remain constant in their positions.

They are only effective when the shell revolves at a minimum distance from the same centre, each water film being likewise of minute thickness.

An additional advantage arises by this arrangement, inasmuch as the water film likewise effects lubrication, materially reducing the friction between the revolving shell and the fixed lips, so as to protect these parts effectively agalnst wear and tear.

I claim:

1. In a suction roll comprising a perfo rated revolving shell and a stationary suction box, the open upper edges of the suction, box in the direction of the longer axis of the shell being whereof in cross section conforms to the contourof the inner surface of the shell, which rigid lips extend circumferentially over a sufiicient distance to cover several rows of perforations in the shell, the shell external ribs .on the suction box between the box and the revolving perforated shell, said ribs having slots or a ertures adapted to permit the passage of waste material and to facilitate the thorough cleaning of the a paratus.

a suction roll as claimed in claim 1, the provision of packing strips of rubber or the' like on. each side of the box below the extended lips, contactingwith the inner I a surface of the shell.

4. In a suction roll according to claim 1, the shell contacting surfaces of said lips being provided with spaced longitudinally extending water receiving grooves adapted to supply the inner surface of the shell and. the1 surface of the lips with a water film or sea 5. In a suction roll comprising a perforated revolving shell and a stationary suction box having an open. top, the u per edge of the longitudinal side walls 0 the box having outwardly extending ri with curved upper surfaces con orming to the contour of the inner surface of the shell.

6. In a suction roll accordin to claim 5,

said upper surfaces of the rigi flanges ex- A tending outwardly circumferentially over a sufiicient distance to cover several rows of perforations in the shell.

7. In a suction roll according to claim 5,

' packing strips of rubber or the like secured to the under sides of the said flanges and extending outwardly beyond the same to engage the inner surface of the shell, the

j end walls of such suction box being packed in contact with the revolving shell by spring pressed anti-friction acking strips.

8. In a'suction roll comprising a perforated revolving shell and a stationary suc- 08 tion box, the open upper edges of the sucprovided with outwardly. 15 extended rigid lips, the upper surface tion box in the direction of the axis of the shell being rovided with outwardly extended rigld ips, the upper surface whereof in cross section conforms to the contour of the inner surface of the shell, whereby the water film on the internal surface of the revolving shell in conjunction with the water film on the fixed lips prevents the access of atmospheric air to the suction area.

9. A suction roll according to claim 1 in which said bearing contact forms water film on the internal surface of the revolving shell and on the fixed lips to prevent the access of atmospheric air to the suction area.

10. A suction roll according to claim 5 in which said surfaces make constant movable contact such that a water film is formed on the internal surface of the revolving shell, and a water film is formed on the contacting surface of each of the fixed lips, preventing access of atmospheric air to the suction area.

In testimony whereof, I aflix my signature.

/ ROBERT JOSEPH -MARX.

id flanges

Images