US 2369192 A
Description (OCR text may contain errors)
Feb; 13, 1945. c. B. QPTON 2,369,192
LIQUID EXPRESS ING PRESS Filed July 28, 1942 2 Sheets-Sheet l W ATTORNEYJ Feb. 13, 1945. c. B. UPTON LIQUID EXPRESSING PRESS Filed July 28, 1942 2 Sheets-Sheet 2 Patented Feb. 13, 1945 UNITED STATES PATENT OFFICE LIQUID EXPRE SSING PRESS Charles B. Upton, Piqua, Ohio Application July 28, 1942, Serial No. 452,611
Claims. (01. 100-50) This invention relates to improvements in mechanical or screw presses of that type, used for expressing oils and other liquids from materials, which comprise a cage or barrel and means, such asaxial screws rotating in the cage, that force the material through the cage and expel it through a more or less restricted discharge opening in the cage, thereby creating pressure by which the liquidis squeezed from the material and escapes through fine screen openings in the cage walls.
Very high pressures are required for expressing the liquidsfrom somematerials, for instance, for expressing the oil from some oil bearing materials, and while the screen openings or perforations for the escape of the liquid have to be very minute in order to effect proper screening of the liquid from the solid matter, neverthelessthe cage lining or screen whichprovides the liquid escape openings, has to be of a strong construction to withstand thehigh pressures to which it is subjected in use, and even so, the screens or linings become worn or damaged and have to be renewed in whole or in part more or less frequently. Therefore, it is preferred practice to construct the cages of such presses with a strong outer skeletonbody or frame which supports and reinforces an annular perforate lining or screen formed by separate screen bars which are arranged lengthwise of the cage and are suitably spaced apart or separated to provide very narrow slits or spaces between the bars that form the drainage or escape openings for the expressed liquid. -These liquid escape slits usually have to be very narrow, for instance, they may vary from say three-thousandths of an" inch to fifteenthousandths'of an inch more or less in width, depending upon the character of the material being pressed or the pressures to which it is subjected. Because of their extreme narrowness it 'is not mechanically feasible or economical to machine or form the screening slitsof the requisite uniformity and perfection in a solid wall'or part forming thebody-or lining of the cage, and
this is an important reason for building the lining or screen of the separate spaced screenbars. Separate, independently assembled and removable screen bars are alsoemployed because they enable the removalor-replacement of one or more bars in case of local wear, damage or deformity in the screen, and so make it possible to repair or restore a cage screen-to proper operative condition without the expense of replacing a whole cage or cage lining.
In the use of presses of this type, it is also highly important or necessary in pressin some materials to provide cooling ortemperature varying means for reducing', altering or regulating the temperaturenf the material during the pressil'lg thereof in order to obtain proper efliciency of operation and insure the required quality of the product. ,Heretofore, such presses have been equipped with means for cooling or heating the cage or the material therein with a view of obtaining the temperature in the cage required to obtain a particular desired result or performance; For this purpose, cages have been provided with channels or passages located within or associated with. the cage body outwardly beyond the cage screen, through which channels a coolin orv temperature changing medium is circulated,but such previous constructions have been found not to give the amount of cooling required for the proper pressing or treating of some oil bearingor other materials'for which the presses are designed. For instance, in a construction in which the cage had separate spaced screen bars within a reinforcing skeleton frame or body, and the cooling or heating channels were formed within said frame or body exteriorly of the lining or screen bars, the heat conductivity from the screen bar through the cage body to the temperature changing medium was not 'sufiiciently rapid or adequate, for reasons which will be explained later, to give the co'olingbr heating required for proper'expressing of liquids from some materials.
One object of my invention is to provide a novel cage construction for presses of the sort men-.
tioned in which the circulating channels for the temperature changing medium are provided in the lining or screen bars themselves, which are in direct contact with thematerial being pressed, 7 thereby greatly increasing the heat exchange efiiciency of the cage.
Another object of'the invention is to provide lining or screen bars for such press cages of improved novel construction which will result in, economy and simplicity in the construction and assemblage of the cage, and also inasimplificaan enlarged scale on the plane of line l-l, Fig. 7, of a press cage embodying the invention.
- Fig. 2 is a similar transverse, sectional elevation thereof on the plane of line 2--2, Fig. '7.
Fig. 3 is a broken side elevation of one of the screen bars of one construction, detached.
Figs. 4 and 5 are enlarged, transverse sections on lines 4-4 and 55 respectively, Fig. '7, each showing twoadjacent screen bars.
Fig. 6. shows1 one of the screen bars'in longitudinal section, a portion thereof being broken out. I
Fig. 7 is a side elevation, partly in longitudinal section, of the press cage.
Figs. 8 and 9 each shows an elevation of the end of one of the screen bars, Fig; 8'sh'owin'gthe same before and Fig. 9, after: makingatapped plug hole therein.
Fig. 10 is a transverse section of a screen bar-of modified;construction.v
Refer-rings tothe drawings. and. particularly .to. L, .21 and. 7-. Aerepresents: the .cage. or, barrel of; pressandlBiindicates Wormsor screwsfixed. 011..a: .shaftextending,axially through. .the. .cage and,; which: rotation actto. .foreematkarial lengthwise through: the cage. and: extrude or ex.- pel, the solid .material. through. the. discharge opening. C atone .end, of thecage. It. is usual in pressesof this. type-toprovide. an adjustable.
coneonmeans. (notshown)v for. more or less restricting.,.the area .of. the discharge opening as may-.berequiredito. effectithe resistance. to the discharge .offthesolid material necessary to create, the, expressing, pressure. on the material in the cage. The cage comprises the usual strong outer skeleton frame, body or structure D having openings. between its component parts and an inner "annular-lining: orscreen E which forms tions are firmly secured together to complete the cage, as by transverse bolts 2| extending through bolt holes in each section and screwed into threaded holes in the opposite section.
As thus far described, the cage is not substantially different from a construction commonly employed in pressesof this type. Except as regards the improvements now to be explained, the cage may be of the described. .or other suitable construction.
The screen bars are of novel construction, as
follows: Preferably the screen bars l0 extendthe full length of the cage, and each bar, which (is. shown to 1 be of generally rectangular cross sectional shape and of greater radial depth than width or thickness, is made with a longitudinal channel .on'ductllthat extends lengthwise in the theperipheral'walloff the pressing chamber'an'd is formedfby a pluralityof separate screen bars I Warranged'longitudina-lly within the cage frame or body D and separated by intervening narrow spaces (11" slits l l whichform the drainage or escape aperturesforthe oil or liquid expressed from-the material beingpressed in the cage.
:In the embodiment of theinvention illustrated inthe'drawings/theouter'cage frame is made in=twohalves dividedon-a:diametrical axial plane of =the cage,- each section consistingpf a single, I
integral steel oastingcomprising strong, 'rigid;
longitudinal bars l2- at opposite sides of the sec: tion and strong-spaced ribs- I 3 of. approximately semi circular form which; extend transversely fromone to --'the ':.other of and t connectithetwo side-bars'ilt. The 'screen barsxlll withjnterventing spacingswedges or devices!flatabetweenitthem areseoured? inplace ain'aeach 'cage frame: section atcth'e innenpconcave'd side thereof; ,betweenglongitudinal center or abutment bars :l-Landdi-fixed to the sideibars I2"ofrthe.frame-sebtion,. and longitudinal :clampingor 'wedge; bars l6 which .are-:disposed-rbetweengroups: of the screen bars and :areaadaptedrto ,b1ewadjnsted,,assa by,"- screw stems 1lJ'-.and:nutss:lBgforrclamping the drainage bars. between thefixedzand: adjustable-holding bars. One of thesabutment hars; asyl5:;,at each of z the oppositevisideszof..the cagm..as:.shown, may
be provided with; inwardly; projecting portions wrwhiclr constitute-breaker bars; for opposing :rotaticnzofzthe material. being pressed-in .the cage.
The: two halves ;.or.;-sections :of .the..-frame .may. be hinged, as on hinge bolts.orshaftslB-on the press frame extending through .lugs atathe. end
portions: oftjacljacentsides .of- -the. two sections. to facilitate opening up the cage, and thetwo secbar substantially from end to end thereof, and is-adaptedto be joined at its opposite ends with pipes. or. other suitable connectionsfor causing a. coolin g. or. temperaturachanging. medium .to circulate through the. bar. lengthwise..thereot.;for.
practically .its. .fullllength. .As..sl'1own, the. bar is proyidednear. oneend with.ann'nletl-port-v 2-3. and.
near the opposite'endwitln anoutletnportau for.
the temperature changing medium, these. ports beingshown as .screw' threaded holes. in .the. outer edge orside of. the-'barfor the attachment of" the mediumcirculating connections. The. bar is. also preferably provided in its ends with. axial threaded-holesl2.5 closed. by screw. plugs. Iii-which can be, removed" toffacilitateremoval. from. the channel. .of any scale. or deposit. which. may .accumulate. therein.
Apicactical and e'conomicahmethod. of making the circulating channels..22-. inthescreen-bars, whichare relatively. longandnarrow, is. illuse tratedinEi-gs. 3-5. As..here.shown, each bar. is
made twolhalves .in. each. of which one-half of just explained, the channelscanbe formed, if
preferred, bydrilling .solidzbarsto .make thezcy lindrical. channel bores 2&therein, .as illustrated in.Fig .ll[l.
.Each screen. bar. .is alsopreferably bevelledat oneside thereof, at its .inner. edgeorzcorner, ,thus providing abevelled face 30. This bevel, instead of. being .made of. uniform width. and." depth throughout .its length, .is preferably. tapered .so as to decreasein widthand.depthlengthwise of-the barin the directionfrommhe feed endof the cage towards the discharge end. thereof, to thereby leavea. narrowz'slitor. space between eachtwo 'ad.-
J'acent .screenzbarswhich .gradually decreases: in width .fromthefeed end .of .theca 'c toward the discharge end thereof. =-The;purpose.of .this, will morefully. appear. presently. The. several screen barsyare preferably of .like..thiclness. and of uniform thicknessl from end-.to. end, .but, as stated, the .bevel 3B.:g-radually increasesin depthfrom .one end to. :the. other of. the For. example, .the bevel may. increase. .inQdepth. about-ten thou; sandths of an inch from end to.e-nd.of.the bar, so that if the... Widthofithe, slit between the. bevel face of one'bar and the ad jacentface of "the next When bar is, for instance, five thousandths 'of an inch at one end of the screen, its width at the opposite end of the screen will be fifteen thousandths of an inch, with the slit gradually increasing in width from end to end of the screen. Thus, with screen bars of like and uniform thickness and uniformly spaced apart from end to end of the screen, the slits between the bars will increase gradually'in width lengthwise of the screen. These figuresfare merely illustrative. The screen bars may be bevelled and spaced apart in the cage so as to give any required width and taper of the drainage slits between the bars. The screen bars may be made in rights and lefts,with the bevelled edges" at opposite sides of different bars. As shown in Fig. 1, this'enables the bars to be arranged in fone quadrant of the cage with the bevelled edges facing one way, whereas the bars in the next quadrant may be arranged with the bevelled edges facing the opposite way. Such arrangement gives the same number of drainage slits between the bars in each quadrant of the cage, whereas, if all of the bars in the cage were arranged with their bevelled edges facing in the same direction, there would be one less drainage slit in one quadrant of the cage than in the next. J11
In the operation of these presses, the material is less compact in the feed or inlet end of the cage than in the discharge end, and the material gives up its liquid more freely or under less pres sure in the feed end than in the discharge end, the pressure on the material increasing from the feed end towards the discharge end. Therefore, it has been the practic to make the cage screens in successive sections lengthwise of the cageiand space the screen bars difierently in the d fferent sections, so as to get spaces between the bars which are widest at the feed end section and are of successively decreased Widths in the simcessive sections toward the discharge endof the cage. This meant that the wedge spacers between the bars in each section had to be of a different thickness and with faces of different angularity from those in each of the other sections. By'employing screen bars formed with the tapered bevels described, the bars can be spaced apart uniformly from end to end by means of Wedge spacers of like thickness and like Wedge taper used throughout the length of the screen or cage,
the wedge spacers being of suitable thickness to give the minimum required width of the slits between the bars at the discharge end of the cage, and the tapered bevels of the bars causing the slits between the inner edges of the screen bars to increase gradually in width from the discharge end toward the feed end of the cage. Thus," the required effective width of the slits at each portion of .the cage is obtained, as for example, slits increasing in width from five thousandths of an inch at the discharge end of the cage to fifteen thousandths of an inch at the feed end of. the cage.
-The channels or ducts of the screen bars" are joined with suitable connections or piping for circulatlng the heat exchange medium lengthwise through the several screen bars. The means shown in the drawings for this purpose comprises inlet manifolds 3| and 32 arranged atopposite sides ofone end of the cage and connected to a common supply pipe 33. The manifold 3| is connected by inlet pipes 34 and unions 35 'with the inlet ports 23 in one end of the several screen bars at one side of the cage, and the other inlet manifold 32 is similarly connected by inlet-pipes 36 and unions 31 with the inlet ports 23 at the herein disclosed, having 20 screen bars 44 inches corresponding ends of the several screen bars at the opposite side of the cage. Similarly, outlet manifolds 38 and 39 are-shown at opposite sides of the cage and connected to'a common discharge pipe 40. The manifold 38 is connected byoutlet pipes 4| and unions 42 with the outlet'ports .24
at the opposite ends of the several screen bars at one side of the cage, and the other outlet manifold 39 is connected by outlet pipes-43 and unions. M with the outlet-ports 24 of the several screen bars at the opposite side of the cage. By such connections, the coolingor heatingmedium is admitted to the corresponding ends of the channels in .the several screen bars and flows lengthculating channels for the heat exchange medium could be made in short lengths and arranged in successive sections in the cage in the manner that solid screen bars have been heretofore arranged, as before mentioned, suchan arrangement would necessitate circulating connections for opposite ends of thebars in each of the several screen sections, which would greatly increase the number of connections and add to the complication of the circulating system. By forming the screen bars with the tapered bevels as described, the necessity for such a multiplicity or complication of circulating connections is avoided, because, as explained, the bars can be made the full length of the cage and give the necessary increasing width of the drainage slits between the bars at the different portions lengthwise of the cage, and it is only necessary to have circulating connectionsat opposite ends of a single set of bars. Drainage slits which taper or decrease in width lengthwise of the cage could "be obtained, of course, by employing screen bars of full cage length which taper or increase in thickness lengthwise, but bars of such form would have to be spaced apart by wedge spacers which are of different thicknesses and having faces of different angularity at different portions lengthwise of the bars. Furthermore, the filler bars 46 (see Fig. 1), which are used between the screen bars and their securing wedge or clamping bars, and the shim bars 41 used between the screen bars and the abutment bars of the cage for clamping the screen bars in place in the cage would have to be of different shape or thicknesses at different portionslengthwise ofthe screen or cage, thus greatly complicating the assemblage of the parts of the cage. These complications are obviated by the use of the described full, length bars with the tapered bevelled edges.
The heat exchange, cooling or heating efliciency of the described construction, in which the circulating channels for theheat exchange medium are formed directly in the screen bars themselves, is many times greater than that obtained by previous constructions, in which the circulating channels are formed in the cage body or portions of the cage which are disposed out wardly beyond the screen or lining bars, as will be apparent from the following:
Assuming, by way of example, a cage such as long and A" thick lining a cage body having 16 ribs, each 1" thick, against which the screen earsbear; there swould ebe" at best 240 -.-s 1m, of contact area between athe- =screen *bars and ribs' fof'conducting heats-from material being pressed, to the temperature changingmedium if the ciricul at-ing channels werelocatediin the cage ribs or otherwise outside of the screen bars.
contact with the material from which the heatwouldbe conducted to the temperature changing medium directly-and bythe" shortest-path through the relatively thin metal walls-oi the screen bars themselves to-the temperaturechanging medium. But, in addition, in the old constructions the effective heat conduction from the screenbars to the cage ribs v'vouldbe far less'because there is not a perfect metal tome'tal contactthroughout the statd' area betweenfi th'e bars and-ribs; since the expressed oil o'rliquids work" into the joints between the barsan'd ribs-,and
mthermore; because the'usual screen 'bars have had fl-a't outer -sidesengaging the" curved inner races-cr me ribs, whichgives a ter small area of contacting surface between" these parts. Thus; the efi'ective heat transfer fromthe material tothe temperature changing medium in the" improved construction of this" application would be many times greater than thethree times larger conduction area above indicated in the improved construction over previous constructions.
'I-t"-will be noted with reference to the constructi'c in of the screen bars having the tapered bevel of theedges for drainage; that increasing' the 'depthof-the bevel would result in increasing the widthof thedr'ainage spacebetween the'bars, and thetaperedbevel the full length ofthe. bar make's' 'it possible-tense spacers'of one size or thickness throughout the full length of the'bars. All the spacers used with these" tapered bevel bars are of the same thickness, and the' drainage spacing between the barsis regulated by the ta- On the other hand, in the improvedconstruction described,the screen'barswould have 660 sq. in.-, or nearly three times'as large an area; in direct pered bevel and not b'y'varying the thicknesses of thespacersbetween the bars. The'tapered bevel the iful-l length of the bar makes it possible to use spacers of one size or thickness, and still secure d-rainage'slots of any width desired, by
changing the tapered bevel on the 'bar itself.
This, of course, makes a very easyassembly.
Iclaim as my invention:
I -1; In a'liquid expressing press having a cage which forms the pressing chamber and comprises an outer'reinforcing frame, and an annular screen lining-said frame composedofseparate longitu dinal screen bars which are detachably secured in said frame in closely "spaced si de by side relation to form narrow 'escape'slits for the expressed liquid between the bars; the improved construction in which each of said bars comprises two longitudinal sections at least one of which-is channel shaped in crcss'se'ctio'n and which aredisposed'edg'e 'to edge -for'r'ningfan internal channel for'the expressed liquid between the *barsfthe improved constructionin which each of said screen barsshas a side thereof-at 'tl'ie iirin'er edge-oftthe bar bevelled and said bevel-gradually increases-iii;
depth lengthwise of-the bar-, thereby forming slits between the screen bars which-taper-lengthwise of'the cage.
3. In a liquidexpressi-ng press -havingja cage which forms, th pressing chamber andcomprises;
an outer reinforcing frame; and an'annular screen lining said frame composed of longitudinal screen barsspaced apart to form narrow escape slitsafon the expressed liquid between the barsathe ireproved construction inwhich each .of said screen bars extends approximately the full length of the, cage and hasa side thereof at'the inner edge of;
the bar bevelled and said bevel gradually increases in depth lengthwise of the bar, thereby forming slits between the screen bars which-taperlengthwise of the -cage.-
- 4. In a liquid--expressing epress-having,acage which for-ms the pressing chamberand =compriscs an outer reinforcing frame, and'an annulariscreen lining said frame composed .of separate longitue dinal screen barssecured in: said: frame in closely, spaced side by side-relation toform narrow'escape slitsfor theexpressedliquid between the bars,- the improved construction in which each of said screen bars has a side thereof at theinner edge of thebar bevelled and said bevel. gradually increases in depth lengthwise oi the bar, thereby. f orming-liquid escape slits between the screen bars which taper lengthwise of th cage, each; ofsaid screen bars has a channel extendin lengthwise therein, and connections are provided forcirculating a temperature'changing medium through said channels. I
5. In a liquid expressing press havlngalcage which forms the pressing chamber and comprises an outer reinforcing frame, and an annular screen lining saidframe composed of separate long-itu -tdinal screen bars secured in said frame in closely spacedsideby side relation to form narrow -esa cape slits for the expressed liquid between the bars,the improved construction in which each-of said screen bars extends approximately.-the full length of the cage and has a side thereof at -the inner edgeof the bar bevelled, and-saidbevel gradually increases in depth from'end to end ofa the bar, thereby forming slits betWeen-thebars which taper lengthwise of the cage; and each of said screen bars has a channel extendinglengthwise therein, and connections areprovided for circulating: a heat-exchange medium through said;
6. In a 'liquid expressing press haw/ingest cage which forms the pressing chamber and comprisesan outer reinforcing frame, and-an annular screenlining said frame composed-of longitudinal screen bars spaced apart to formtna-rrow escape :slits'for the expressed liquid between the bars, the im 7 proved construction in which said screen bars extend approximately the full length 013 171 18 cage and are separated by spacing members otunitorm thickness disposed at intervals lengthwise of the bars and each of which barsisotuniform thickness from end'to end-throughout the major po r: tion of itsradialdepth but has; a side thereof at the inneredgeofthebarbevelled, which bevel gradually increases indepth lengthwise of thef bar, thereby forming liquid escape slitsbetweenthe-bars which taperlengthwise-of the cage 7. In a liquid expressing press-having a cage which forms the pressing chamber-andcomprises an 'outerreinforcingframe, andan annular screen lining-said frame composed, of longitudinal screen bars spacedapart to form narrow escapeslits for the expressed liquid between the ba l-5, the im proved construction in which said screen bars extend approximately the full length of the cage and are separated by spacing members of uniform thickness disposed at intervals lengthwise of the bars and each of which bars is of uniform thickness from end to end throughout the major portion of its radial depth but has a side thereof at the inner edge of the bar bevelled, which bevel gradually increases in depth lengthwise of the bar, thereby forming liquid escape slits between the bars which taper lengthwise of the cage, each of said screen bars having an internal channel extending lengthwise thereof, and connections are provided for circulating a temperature changing medium through said channels.
8. In a continuous liquid expressing press of that type which comprises a cage forming a press,- ing chamber, and a pressure screw that compresses and moves material along in the pressing chamber and forces solid material out through an end discharge opening thereof, and in which said cage comprises an outer reinforcing frame and an annular screen that lines said frame and is composed of numerous separate longitudinal screen bars removably secured in said frame in closely spaced side by side relation to form between them narrow slits for the escape of liquid expressed from the material, that improvement in the construction of the press cage in which said outer reiIlfOICiIlg frame includes sections which are relatively movable for assembling and removing said screen bars, said several separate screen bars have internal circulating channels extending lengthwise therein approximately from end to end of the bars, and connection are provided for circulating a temperature changing medium through said bar channels, which connections include relatively movable parts enabling the assembling and removal of said screen bars.
9. The improvementin a continuous expressing press as set forth in claim 8, in which said channelled screen bars extend approximately the full length of the cage screen, and said circulating connections include inlet and outlet manifolds with branches separably coupled to the "several screen bar channels.
10. In acontinuous liquid expressin press of presses and moves material along in the pressing chamber and forces solid material out through an end discharge opening thereof, and in which said cage comprises an outer reinforcing frame and an annular screen that lines said frame and is composed of numerous separat longitudinal screen' bars secured in said frame in closely spaced side by side relation to form between them narrow slits for the escape of liquid expressed from the material, that improvement in the construction of the press cage in which said several separate screen bars extend approximately the full length of the cage screen, said liquid escape slits taper continuously from end to end thereof lengthwise of the screen, said screen bars have channels extending lengthwise therein, and connections are provided for circulating a temperature changing medium through said channels.
CHARLES B. UPTON,