US2416073A - Centrifugal separator - Google Patents

Description

Feb. 18,"1947. MSMELY 2,416,073

CENTRIFUGAL SEIPARATOR Filed oqt. 27, l1942 s sheets-sheet 1 V. SMELY CENTRIFUGAL sEPARAToR I Feb. 18, 194.7. v

Filed 001;. 27,` 194.2

3 Sheets-Sheet 2 Feb.`l8, vl9r4'r7. v, SMELY I 2,416,073

CENTRIFUGAL sEPARAToR Filed Oct. 27, 1942 3 Sheets-Sheet 3 Patented Feb. 18, 1947 UNITED STATES PATENT OFFICE `v Application October 27, 1942 Serial No. 463,515

In Great Britain October 30, 1941 4 Claims.

particularly for separating solid material from liquids and such as are used, for example, for separating sugar crystals from the mother liquor or for drying small washed coal by separating the water therefrom to reduce the moisture content of the coal.

In general such driers are intermittent in operation and while some continuously operating machines have been proposed they are not altogether satisfactory in that in addition to requiring a high power consumption and being subject to relatively rapid wear they have the further disadvantage that due to the scraping action involved they cause the crushing of the particles with consequent diminution in size and hence are unsuitable for use in the sugar industry `from which parts are omitted.

Figure la is a perspective detail of the connection between the two sections alf and o16 of the main shaft A showing the spout structure, section L15 being broken away and shown in section.

Figure 2 is an end elevation of Figure 1 looking on the left hand end of that figure but showing the top part of the end walls of the outer and inner drums at this end thereof broken away to reveal the interior of one of the troughs containingr an endless perforated apron. this trough and its associated apron and spout for delivering to the endless apron the material required to undergo treatment, being shown in section.

Figure 2a is an enlarged transverse section on the line 2-2 of Figure 2.

Figure 3 is a fragmentary plan view of a section of one of the endless perforated aprons, showing how the surface of the apron is made up from bar elements secured to extend transversely between the transversely spaced endless ropes which are incorporated in each endless apron.

Figure 4 is a transverse section on the line ll-A of Figure 3.

Figure 5 is a section on the line 5-5 of Figure 3. Y v

Figure 6 is an enlarged end elevation of one of the bar elements and showing the eye formation of the ends thereof.

Figure 'l is an end View of the bar seen in Figure 6 and looking on the left hand end of that flgll- Figure 8 is a detail ofthe planetary gearing.

In carrying my invention into effect in one convenient manner as `illustrated in the drawings I provide a stationary or non-rotary outer drum t, having annular end walls t2, i12 through which the ends of the hollow shaft a extend in a rotary manner and upon which shaft a second drum b is mounted to rotate with the shaft a and within the outer drum t, there being an annular space t13 formed between the inner rotary drum and the outer stationary or non-rotary drum.

The end of the rotary hollow shaft a, adjacent the end wall i12 of the outer drum t is closed by a plug d10 having a central shaft all which extends in a rotatable manner through the center of the end wall i12 and is supported in a journal bearing 0,12 on a pedestal 0,13 fixed on a `foundation or floor 0,14.

The shaft a carries the inner drum b and eX- tends from one end of the outer drum t to the other, passing through the ends of the outer drum, and is composed of two hollow or tubular sections, namely a major section als and a minor section a16 joined by a series of radially extending spouts co1 carried with a dividing plate all which insures passage of material from section als through the spouts a1 and prevents passage of the material into the section G15. The pipe section am is rotatably supported in a journal bearing a18 in the center of the annular end wall t2 of the outer drum, such journal bearing being provided upon another pedestal 1,19 fixed upon the foundation or iloor 0.14. The section a16 and the spouts a1 as well as the plate all have an interior lining a2 of rubber. `Incidentally the plate all is provided with a centralopening 1.21 for the passage of pipe s to be hereinafter described.

The cylindrical walll of the inner rotary drum b is perforated and atene end this drum is fitted with an annular end plate b1 secured at its center upon the hollow shaft a and arranged to have sealed rotary engagement at its outer periphery with a ring t14 xed to the inside of the outer non-rotary drum t. At its opposite end the inner rotary drum b is fitted withr a ring bu having a central opening Z212 forming one side of the upper portion of aspout q; the opposite side of which is closed by the end wall i12 of the outer casing and which spout serves to receive material discharged thereinto from the inner drum during the operation of the centrifuge.v

The upper end of this delivery spout is sealedolf from the annular space t13 between the inner and outer drums by the inner drum being iitted on its outer surface witha ring i213 arranged to have rotary sealing engagementwith a ring 15 fixed to the inside of the outer drum.

The shaft afand chutes a1 andthe inner drum b are rotated together from a pulley a4.

The drum b forms the vessel in which the centrifusine operation is., carried out upon material introduced into the interior of the ldrum from as to be rotatable therewith as the apron is itself made to travel longitudinally of the'drum.

A preferred arrangement consists in the provision of the three such endless aprons arranged in uniformly one another about the center of the drum.

Each apron is provided with perforations andv any liquidseparated from the material being carried-by the apron will percolate through the apertures in the apron due to centrifugal action and may ibe either deflected sideways or may be allowed to pass through the return siderof the apron thus assisting in dislodging any particles which may become wedged in the per-forations of the endless apron. Moreover since the centrif.

ugal force acting on the return side of the apron is about doublerthat on the carrying side centrifugal force alone should keep the apertures clear.

V There are many ways in which the apron may `be constructed. Since, however, there are Very large stresses developed in the apron I prefer'to form the same as shown in Figures 3 to 7 from a plurality of longitudinally disposed endless loops of wire rope d to which are attached transverse wedge-shaped bars e forming the apron surface. Y In order to protect the wireropes d from abrasion I preferably cover them with rubber sheath- Y ing f and this sheathing also serves the further i purpose of retaining graphite or other lubricant -with which the wire rope is impregnated before y being covered with the sheathing. Y

The 'transverse bars e are preferably of double wedge or substantially lozenge shapev as clearly `The bars e must be secured in place upon the l ropes in Such a manner that they are not likely to be detached due-to the centrifugal forces developed. This may be effectedby forming the 1 bars with eye ends e by which they may be i threaded upon the rubber sheathing f onY the ropes, there being interveningwashers g between the adacent eyes and on the outside eyes as shown in Figure 3.

The; longitudinalY ropes d are spliced to form endless loops and are then covered with the rubber sheath. Y

spaced circumferential; relation ,to rotary inner 4 to ensure a good grip between the tube and the outer rubber covering.

As shown in Figures l and 2 the aprons, drums and pulleys are disposed in U-shaped tunnels or troughs l, the side walls of which are flanged outwardly as at Z2 and secured to the inner surfacey of the inner drum b and as the latter is carried by the shaft a rotate therewith.

Any convenient means may be employed for imparting translational motion to the endless aprons. In Figures 1 and 8 this is shown as being eliected by planetary wheels n carried upon the end wall blo of the rotary Vdrum b and engaging a stationary sun wheel ym mounted about the hollow. shaft a and'secured upon the pedestal al", the planets operating to Ydrive worms o engaging worm` 'wheels .h1 on the aprons supporting drums h. v l.

For the purpose of feeding tne material to Vbe centrifuged to the aprons Iprovride a hopper p xed relative to the bearing am by which the material may be fed to the interior of the minor section als of the hollow shaft a, and the latter will be formed with or have secured thereto spouts a which extend through the adjacent ends of the adjacent troughs and by means of which the material is directed on to the aprons. In orderto facilitate even distribution of the material across the width of the aprons the spouts may be provided with rubber-lined difusers' a2 as shown in Figure 2. Y

The material having been carried the length of the centrifuge is discharged into the collecting hopper q and as the material is flung out with considerable force I prefer to line the collecting hopper and its-outlet q1 also with rubber as at q2. When the aprons or other internal parts of the machine require to be flushed with liquid or steam the flushing medium may be introduced as by the pipe s through the hollow shaft a and thence through any number of jets or sprays s' disposed along the carrying side ofthe apron.

The particles of water ejected from the material under theaction of centrifugal force may collected in and escapes from the troughs t in Theaprons are arranged upon end drums hi sleeveslrlFigure 2) andprovidedwith periph- The driving l either or both of which may be driven, and durg Q ing the rotation of the drum theyY are supported i' by rollers 7c at intervals along the lengthof both the carrying and return side, and since the loads i upon the rollerswill be heavy I prefer to form the sainev from steel tubes covered with Yrubber with the sun Wheel m, whereby the endless apronsare caused to traverse the troughs Z within the inner drum, in the direction of the arrows in Figure l, and while these aprons are being carried aroundY with the drum. The material required to undergo treatment is introduced into the centrifuge by way of the hopper p and is discharged from the delivery spouts a1 direct upon the inner runs of the endless aprons at a point near one end of the troughs containing these aprons. l The material will be held against the apron surfaces by the centrifugal forces generated and at the Sametime will be made to traverse the troughs While this is taking place the liquid separatedV from the material will pass through the perforais claimed and desired to be secured by Letters Patent is:

- 1. A centrifugal drier or separator comprising a stationary or non-rotary outer drum, a rotary drum mounted within said outer drum to extend longitudinally of the latter -and spaced from the outer drum so that an annular space is formed between the outer and inner drums, the cylindrical wall of the inner drum being perforated to provide communication between the interior of the inner drum and the said annular space, a hollow shaft rotatably mounted in the end walls of the outer drum and carrying the inner drum, the

Meanwhile the material remaining `1 said shaft extending longitudinally through the l interior of the said inner drum, trough forming members secured to the inside of the cylindrical wall of the inner rotary drum at uniformly spaced circumferential distances apart and forming separate hollow troughs extending longitudinally of the inner drum, an endless perforated apron mounted within each said trough to eX- tend and travel longitudinally thereof, gearing means for connecting the hollow shaft to the aprons for imparting translational movement to said endless aprons as the same are carried around with the inner rotary drum, an inlet hopper at one end of the outer drum and communicating with the interior of the adjacent end of said hollow shaft, delivery spouts open at their inner ends to the interior of the said shaft at said end thereof and open at their outer ends to the interior of said troughs at the ends thereof adjacent the said hopper, there being one said delivery spout provided for each trough and each said spout being adapted to deliver the material required to undergo treatment, and fed into the hopper, directly onto its corresponding endless perforated apron at one end thereof, a discharge spout for the centrifuged material, said discharge spout being provided at the opposite end of the outer drum remote from the inlet hopper and being open to the adjacent end of the inner drum, whereby the centrifuged material is able to pass from the troughs into said discharge spout after the material has been constrained, by said translational movement of the perforated aprons, to traverse the length of the troughs, and outlets in the cylindrical wall of said outer drum adapted for the discharge from the said annular space of the matter delivered, during the centrifuging operation, into such space from the troughs and entering such space through the perforations in the cylindrical wall of the inner rotary casing, the perforated wall of the latter constituting the outer wall of the said troughs.

2. A centrifugal drier or separator as claimed in claim 1 comprisingr a pipe arranged within the said hollow shaft to extend longitudinally thereof, and branches from said pipe opening into the troughs, the said pipe serving to convey washing fluid which is directed onto the aprons in said troughs via the said branches.

3. A centrifugal drier or separator as claimed in claim 1 comprising rollers in the troughs at each end thereof and supported by the inner rotary drum to rotate therewith, the said rollers being adapted to support the opposite ends of the perforated endless aprons, a sun wheel on vsaid outer drum and planetary wheels on said inner rotary drum meshing with the sun wheel and geared to the apron supporting rollers to drive the latter so as to impart the desired translational motion to the aprons.

4. A centrifugal drier or separator comprising in combination an outer drum and an inner drum both horizontally disposed and the inner drum being rotatably mounted within the outer drum and being spaced from the latter so that an annular space exists between the twoV drums, a hollow shaft carrying said innerdrum and rotatably mounted in the end walls of the outer drum, a trough extending along the inside of the inner drum from end to end thereof and bounded on its outer periphery by the cylindrical wall of the inner drum, the said cylindrical wall being perforated to provide communication between the interior of the trough and the said annular space and the trough being closed along its inside Wall l within the inner cylinder, an endless perforated apron mounted within said trough to extend'longitudinally thereof, rollers within the trough at the opposite ends thereof for supporting the endless apron, gearing meansconnecting the hollow shaft to one of the apron supporting rollers to produce translational movement of the apron longitudinally of the trough during the rotation of the inner drum, a hopper at one end of the outer drum and discharging into the adjacent end of said Ahollow shaft, a, spout open to the said end of the hollow shaft and extending outwardly therefrom and through an opening in the wall of said trough near the end thereof adjacent said hopper, whereby material fed into the latter can be directed from said spout directly onto the apron surface, and a discharge spout for the centrifugal material, the upper portion of said spout being formed at the end of the said outer drum remote from the said inlet hopper and being situated between the adjacent end wall of the outer drum and the adjacent end Wall of the inner drum, the last mentioned wall having openings through which the material may be discharged into the discharge spout from the said troughs.

VACLAV SMELY.

REFERENCES CITED The following references are of record in the y file of this patent:

UNITED STATES PATENTS

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