US980891A - Dry ore-separator. - Google Patents

Description

W. W. BGNSON.

:om ons summon.

APPLICATION ILED 00T. 27. 190B.

Patented Jan. 3, 1911.

lil l b I w1 lilllii.. l .HHIINMHHI I oo o 'F1 is Glxhtueooe W. W. BONSON.

DRY OBB SEPABATOR.

LPPLIGATION 111mm om. sv. 190s.

980,89TLs 'UNITED STATES PATENT OFFICE.

WILLIAM W. BONSON, OF DUBUGUE, IOWA, ASSIGNOR TO BONSON DRY 'CONCENTRATOR .CO., OF DUBUQUE, IOWA, A CORPORATION OF ARIZONA. TERRITORY.

DRY cnn-SEPARATori.

Patented Jan. 3, 1911.

Application tiled October 27, 1909. Serial No. 524,975.

ters Patent of the UnitedStates were granted and issued to lVilli-am lV. Bronson and iVillson L. McLaughlin on the 7th day of September. 1909, 'and vnumbered 933,053.

'In what it consists, its manner of con'-v struction, mode of operation and in what particulars it is ditlierentiated' from the aforesaid machine will be fully explained -in 'the following specification and claims v and illustrated in the drawings accompany- .ing the same and made apart hereof.

Figure 1 is a side elevation of the jig table and moth` of supporting it. Fig. 2 1s a perspective view of Fig. 1 wit-h part cntl away showing the construction ofthe sustaining grate bars. Fig. 3 is a head end elevation of the jig and supporters, Fig. 4 is aperspective view of a vportion of the table showing the gates and a part cut away showing the method of operating same, and the ore concentrating bed with the retarders thereon. Fig. is a plan viewl of one of the girdcrs that carry the gates, and a plan viewv of a portion of the ore detiectors. Figp is a side view7 of Fig. 5. Fig. 7 is a section on line w-rv of Fig. "4. Fig. 8 is, a sectional view on line fz/-g/ of Fig. 9. Fig. 9 is a plan view of the table. J

Like characters of reference denote corresponding parts in cach of the drawings.

Referrinor to the drawings 2 designates the jig which consists oiga table 4, beneath which is an air box 5 and 'pivotally mounted on standards 6. Tlie'standargls are formed into rings or cups 10-1t their tops, which form bearings for thelanlesfl -to which the jig is attached The lower end ofthe standards are similarly `-formed and are pivoted upon the shaft. 1G which have their bearings 18 rigidly secured upon the foundation 20.

In order to provide for the inclination.

lengthwise of the jig the standards at the foot are set on the foundations 20 at clifferentheights and this inclination may be varied by raising or lowering either foundation, whereby it is adjusted to the required height to adapt it to different conditions of the massv to be separated thereon. It is often desirable to have the table also incline sidewise or laterally,jand a convenient mode if making such inclination is given by inserting a wedge 22 between the axle 12 and the bottom of the jig 2. This inclination may be varied by the different thicknesses ot' wedgesor in any convenient way to also adjust the j igfor diil'erent. conditions of the mass to be separated.

To the frontend ofthe jig is coupled a shaft 26 which is connected with the power whereby the jig is given a short reciprocating motion. The means -Whereby it is reciproeated may bethe saine' as set out in the aforesaid patent, but any other mode may be used.V It isvintended to impart to the jig a reciprocating motion kupward in the arc of a circle, and as the jig is .reciprocat'edonly a short distance it will have a trembling or shaking motionwhereby with the air thatx is. forced through the mass to be separated, such mass will be immediately stratified.

' The table which is secured on the top of -the air box 5 is preferably formed ot cast metal having the' side bars 27 and grate bars QS. lt is important, onv account 'otI what is placed over and upon this grate, that these bars 28 should be accurately made and that they should be exceedingly rigid and therefore. they are cast and then the bars machined. Upon this grate is stretched a mesh 30 preferably of fine textile fabric which extends over the upper surface of the grate and through which a current of air forced. Against the under side of the grate in the air chamber there may also be stretched a coarse mesh 31 through which the air is delivered to the mesh 30 by a more even distribution, but this4 is not. a necessity only under certain conditions of the mass, usually when the mass is reduced to a line powder. air for aiding in the separation of the ore is 'introduced into the air box in the base ot the jig through a flexible pipe'SZ which is connected with a blower in substantially the .sa-mc manner as in the above mentioned application, and since any other convenient The serilwrl heroin.

38 of the table leavinglja space 4 0fibe Ween 135 vlt is of r `une imoortance that these oi'e des -Underneath these gir ers 44, 45 nnd'fltl the .detlectors 35 ure;groovcd or cut through or Inode muy he used it is not niiuutely de- Upon the inesh El() nre secured ore deflecors 35 .which nre set parallel to each other and above und parallel to the grate bars 28 und et. nn angle to the length et' theta'ble le-eters be sel" parallel Withand rest upon und hc of prscticully the saine width as the grate hors, not only to provide for the stability et" the table and protect. the mesh but also te prevent any interference of the nir up nr-tween the grate bars through the mesh.

Upon the ore dcfiectors 35 ure secured girngue dr-tlectors 15G that are set et an anglev to. the dette-eters und also at nn :ingle to the length t the jig. -n order that there may be grr :igidity to the table andnnitorinity in the runways V'both for the; ore und gungue, und also more accurately peral- ,lel the ore detlectors 35'With the'grate bars '28. the delico- tors 35 and 36 are preferably cust together and machined.'

The detlectors 3G on thetir'sdivisiofof the tnblemny' be dispensedjxvith'qand still there would be a separationofthe orebut. not as fast, :is the detlectors fserve to 'force the gangne fromoif the ore'nafterjftheinss' has been stratifiedby the actionfof'v theair and motionof the jig.' The deliecto'rs 3l :ire preferably cut ott at one end toward t 'dei the ends of the'fdeicctorsand thefside the table as a'runway for ythe'gangue thatis separated fromjthe ore on thisffdivisfion Longitudinzilly ofl thegtablefffnd'e little `to oneside of the centernresecured tothe endf of the table, beams "or girders,r44, 45

and 46 which rest upon the ore delectors-SS. Theunder edges of these girdersare .pro-- vided with agroove 48 and with vertical openings 50. lIn the grooves 48there is ady y justably secured gates 51, 52 and-53. To these gates are secured pins 55. which :ire 'adapted to project up through the opening 50 in the gir-ders, and are provided with screw threads near their tops. .For the pur` pose of adjusting these gutes todifferent.; l heights, thereare provided keepers'-5ft-Tsecured to the upperedgeof the girdershy the' screws 58, and in these'keepers are locatednuts tl() which ae'ndapted to en nge'fthcj threaded end ofthe .pins ,55 .and a just the gutes vertically in the rooves of the girders.V

nearly through substantially the sume width :as the width of the gates, so that the 'gates may be adjusted vertically down to or nearly to the mesh. There may be one or more of the gates according tothe kind nud classifi-A cationof orc to be separated. In the drn'- ings Ihnve shown three secured parallel to would be suflicient. It is not a necessit that these. gates run exactly lengthwise t i l the bed but should be set at an angle to the deflectors and substantially dividing the table lengthwise. Between these gates therel is no necessity for the gangue detlectors 3G and hence none are shown, though they may extend through this spacebetween the gates. These gates serve to divide the table on which the largest part of the gangue is seported from the ore from the side on which is formed the concentrating ore bed from the bottom of which the ore 1s constantly' drawn olf while the ore is delivered on top of the bed from the other side of the division of the table.

The division of the table substantially lengthwise gives an enormousl capacity to the machine, The mass is stratified almost immediately on being 4delivered onto the table, the gangue suspended by the action of -the'air and aided by the motion and pitch Hoff-the table, is'forcedby the'gangue de- 'flctors at a 'great rate of speedy into the runway on one divisionzof the table and down the end ofthe table' -'at-1f'.. The. ore travels muchg'more'slowly as'the' air pressure Vis not strongenough to suspend it and its movement, is governed raeticallyby the throw andpiteh of the ta 1e. Thefriction of such y `a largefmountioffgangue is sulicient to ectoi's'on-the gangue side-ofthe divisionv of thel table. .Theffirst" gate is therefore left suliciently high that allv thev ore, the middlings' and necessarily some of thegangue wilL ass under it. The Asucceeding ggites V are a justed so as to allhvvn free passage of the ore and yet retar'theiovv of vthe, gangue sol that'ity will rise` 'above the ore deectors and be carried down between' the gates over the end of the tabled?, B and C; v

One of the@essential d'terences' between this `51p licationgandlthe before mentioned patent 1s k'the""Sii'btn tially longitudinal di'- vision of the table andthe means for form'- ing andin'aintainingfan ore concentrating bed, which has been found hy experiment to be. o fle'xcecding importance 1n the purity of the separationof ores,A es eeially where the mass-to be se arated has in it various kinds ,o f'o'res of 'di cient-specific gravity. Along the,outerfvlongitudinal edge of the'table is 'secured another .girder 62 similarly supplied `with n'groove inits'lower longitudinal edge inwvhiehfis set another gate 64, a d npted to be adjusted onto thelmesh and form with the e' mesh a tightxjoint.- This gate is adjusted vertically in the same manner. as the other gates.' Between" the gate 53 andthe outer 'gate 64 'is located the concentrating bed G5. The onx f aztle'ctors 35 are continued over the iso table at this division and help to provide means Afor forming the ore bed. Over the ore detlectorsare set at au angle thereto and at an angle to the length of the bed, retarders (33 which preferably extend from the girder (Si). about two-thirds across the ore concentrating hed and are set at a ditt'erent angle to the detlectors 35 from that of the detiectors 3G.

The detiectors :Bti hasten or crowd the separation b v forcing the gangue from ott' the ore on the other division ot' the table, but the retarders (i8 aid in forming the ore concentrating bed by retardingthe ore and gangue upon the bed until there has been a complete concentiption of the ore and all'of the pure or heaviest values have settled and are ready t-o be drawn off'fron'i the bottom of the bed from under the gate (34.

The ore bed could not be vformed on the gangue side of the division of -the table as the ore is passing too rapidly down between 'the ore dcfiectors and too large a bod)y of gangue isA passing over the saine so that they friction would carry with it the ore into the gangue. Therefore, to form the ore concentrating bed the ore and. thegangue .left must travel vat a much slowerrate of speed than it travels when stratified from the gangue at its delivery onto-the table.

`Along the side of the air box 5 and beneath the gate .(34 is a chute 67 for collecting' and disposing of the ore as it ls deliv` ered from beneath the gate (S4.

At 'the front end above the table is a hopper 66 which extends acrossl the table to near the first gate and through which the mass to be separated is delivered along the head of the table.

The manner of operating my device is suhstantially as follows. The mass to be separated is first surface dried and classified then delivered through the hopper Gt along the,`

head of thevfii'jst division ofthe table amid the deitectors 35 and 3G and at thcanie time the air is turned on into theair box 5 through the pipe 32 whereby it isforced up .through the mesh and through the mass.

At the same time the table is given a reciprocating motion which taken with the air immediately stratifies` the massraising the gangue to the topand leaving the ore between the deflectors 35, and asthe table is inclined both longitudinally and laterally -the largest-part. ofthe gangue will be forced hv the gangue detiec'tors 36 toward the side of the table and through the runway over hc tops of the-deflec'tors 35 and off at the end A of the table. This will dispose of most of tine/ganglio.l out. the ore; the middlings and spine of the gangue will be carried under the.

ga'te 51.

Tliegates 5'1. 52 and 53 have previously been 4adjusted in such a`manner that; lthe gate 51` is nearlyto the top of the orc detieetors 35, the gate 52 down at about half of the width of the detiectors -35 and the gate53 a slight distance lower down. As the ore and middlings together with someof the gangue pass in the runways between the ore detiectors 35 under the gate 5l between the gates 51 and where there are no gangue detlectors the middlings and some of the gangue will pass down and be delivered over the end of the table atI B. The or'e will then pass on under the gate 5'2 and some more of the gangue and middlings will be `delivered over the foot of the table between the gates 52 .and 53 at- C, and the ores of ditferent values together with the middlings and some of the gangue will pass under the gate 53 and be delivered to form the ore concentrating bed, then the second division of the table by its construction including the retarders (i8 and the important space between the ends of the retarders and the gate 53. will rapidly dispose of the greatly reduced and com-entrated mass thereon and send the remaining gangue and middlings ott from the cone ntrating bed around the ends of the retarders into the space and down off from the vend of the'table at H. while'the concentrated lore will be drawn otffrom the bottom of the bed under the gate 64 as fast. as it is .delivered uponthe concentrating bed. It will bef seen that though the separation is e.\feeedingly rapid'after the concentrating 'bed is once formed 'still the purity of the separation will always he preserved as long as the concentrating bed is maintained. At -this -time in order to form a concentrating bed of ore which is the great essential in the perfect separation of ore, the gate 64 is adjusted down to., the mesh and will not allow anything to pass beneath it. .and some of the middlings are delivered upon thisl bed from underneath the gate into the spacel'ietween the gates 53 and G4 their movementl will be arrested by the 'gate't-l and retarded by the retarders G8 andI will soon be'tlled nearly` to the top 0f the defleetors and with certain lrinds of ore to near the top of the retardcrs 68. Since the retarders tits" retard. the movementof the4 mass and especially of the gangue A.and other lighter particles thatl are stratified on top of the pure ores. in a short time the ore concentrating bed will be formed,'comp0sed of the heavier ores like gold, silver and copper at the bottom with those of lighter specific gravity above and on top the middlings and gangue. Then the concentrating bed is fullvformed thenv the operator raises the `gatet4 a short distance sufficient to allow the ore to pass out from beneath this gate into the chute 65 and the gangue and middlings that'are on the Surface of the ore bed will gradually pass around the ends of the retarders through ,the space and be delivered over the end of the table at H. The opera- Then the ore tor then watches the ore bed and varies thev i esoei height ofthe gate G4 until it will deliver the pure ore. into the chute as fast as it is delivered upon the bed from beneath the gate 53 and thus carefully maintain the bed'of ore amid the deflectors 35 and retarders 68.

It will be seen that it is exceedingly nec essa ry for the pure separation vof the ore that the ore bed 'ne formed and maintained at apredetermined depth according to the kind and quality of the ore to be separated, and at a place on the table where the ore is practically free from gangue so that the -friction of a small amount of gangue. passing over the ore will carry with it but very little if any ore over the end of the table. Vhen the ore concentrating bed has been formed the heaviest particles of the concentrates will be always at the bottom of the ore bed,

and the middlin s together with whatever angue is still le t will remain on top or be elivered over the end H of the table.

It will be seen that it is ofthe utmost importance that the construction of the ma# chine between the gates 53 and 64 shall be such that 'the operator can arrest and retard the movement lof lthemassand thus form an ore concentrating.; bed of the desired thickness according tothe, various kindsofores in the mass to be se rated-fand thenl mainv tairiithat concentrating b edwhile the ore of vthe highest valufes is drawnoi ,from the bottoni of the concentrating bed as fastaas 'it' is delivered thereon and further all the gangue and lighter product will .be carried out around the ends of the retarders and delivered over thetail ofthe machine at-'I-I.

Having now described my invention what I claim and desire to secure by Lett-ers Patent is:- t"

1. In la. dry ore Separator, a table provided with a mesh, 'means for imparting motion to the table, means for forcing air through the mesh, means for dividing the table vvlonvitudinally, means for forcing the gangue rom 'off the -stratified mass on one sideof the dithe table, ore deflectors set on the mesh atan angle to the length of the table, -gangue de- 'fiectors set upon the ore deectors at au fing-le thereto and at an angle to the length ot the.

table, an adjustable gate set lengthwise of the table dividing the table, means comprising an adjustable gate for forming an ore concentrating bed on one divisionj of the table, and means forl maintaining Isaid ore l bed at a given depth while the ore is drawn ofi' from thle bottom of the bed beneath the gate. Y

3. In a.' dry ore separator, a table, a mesh upon the table, means for forcing a constant current or" air through the mesh, means for imparting motion to the table, a gate set sub stantially lengthwise of the table dividing the table, means for ormingnn orc concentrating bed on one side of the table consisting of ore delectorS, retarders, and a gate at the end of the ore detiectors adapted to be adjusted to aid in forming the bed and to draw off the ores of heaviest values from the bottom of the bed while. the partially separated oie lis delivered from underneaththe giisional gate upon the o're concentrating 4. In a dry ore sepaiiator, a table provided with a mesh, means for forcing air through the table, means for imparting motion to the table, means .for dividing the Atable in substantially a longitudinal manner, means for removingl part of the gangue from one division oft e table, and means'including diagona'lly disposedV detlectors set upon the table with. retarders u on the deflectors at an abigletheretm an a gate onone side of the forl formin 'an ore concentrating bed upon the other (Ii-vision of the tableand for -.ms'iintainin said bed.

. In a ore separator, a table, a mesh upon ,the tab e, means for forcing air throu h the mesh, means for imparting motion to t e table, an adjustable gate for dividing the table substantially lengthwise, means for rej moving part of the gangue from one division ofthe table, and means for forming an ore concentrating bed upon the other division of the` table.

6. In a di'v ore separator, a'table, a mesh upon the table, means for forcing air through the mesh, means for imparting motion to the table, a gate for dividing the table substantially lengthwise, means for adjusting the gate upward and downward, means for partially removing the gangue from olf the 'ore on o ne side .of .the gate and means for forming an ore concentrating bed on the other division of the table by arresting the move-l ment of the mass upon the mesh over a constant current of air. t

7; In a dry ore. separator, a table provided .with a mesh, means for forcing a constant dividing the table-lengthwise consisting of a girder 1provided Ywith a groove and agate adapte( tobe adjusted in the groove in the girder, means for removing part of the angue from ott the ore on one side of the division, and means for forming an ore concentrating bed on the other division of the table. 8. In a dry ore separator, a table provided with a mesh, means for forcing a constant current of air through the mesh, means for imparting motion to the table, meansfor dividing .the table substantially lengthwise consisting of a girder provided with a groove lengthwise therein-and vertical openings therethrough, a gate. provided with arms adapted to engage the openings in the girders, means attached t0 the arms for adjust-A ing the gate in the groove in the girder, means for removing part of the gangue .from oft the ore on one division of the table,

and means for forming an ore concentrating bed on the other division of the table.

9. In a dry ore separator, a table, a mesh upon the table, means for imparting motion to the table, a gate dividing the table Substantially lengthwise, means for formin an ore concentrating bed on one division o the table by arresting the movement of lthe mass and means forretarding the movement o the mass forming the ore bed while it is subject to a constant current of air up through the mass. y

10. In a dry orc separator, a table, a mesh upon the table, means for imparting motion to the table, means for forcing a currentof air through the table, a ate dividing' the. table substantially longit-u inally, means including detlectors upon the mesh and re# tarders on the deiiectors at an angle thereto for forming an ore concentrating bed upon one division of the tahle, means including a gate upon the outer side of the ore concentrating bed-for arresting the movement of the mass while it is subject to the ressure of air therethrough until the bed is ormed.

11. In a' dry ore separator, a table provided with a mesh, means tor imparting motion to the, tahlc, means for forcing air through the table, a gate dividing the table in substantially a longitudinal plane. means for forming an ore concentrating bed on one division of thetable consisting of ore deiectors and a gate along th'l ends of the ore detlectors adapted to be, adjusted to stay the movement of the 'mass until the concentrating bed is fully formed.

12. In a dry ore separator', .a table provided with a mesh thereon, means for in iparting motion to the table, means for forcing ay constant current of air through the table, agate dividing the table substantially in a longitudinal manner, and means for forming and maintaining an ore concentrating bed on one division of the table consistingof lleectors set at an angle to the length of the table etarders on the ore delict-tors at an angle therto together with an adjustable gate, set alongr the ends of the ore detlcrtors and rctarders.

13. In a dry orf.l separator, a table, la mesh upon the table, ore deflectors diagonally disposed 'on ine mesh, ganguc deflectors set upon the ore detiectors at an angle thereto and at an angle to the length of the table. means for forcing a constant current of air through the mesh, means for imparting motion to the table, a gate upon the derlectors at an angle` thereto and dividing the table substantially lengthwise, and means for forming an ore concentrating bed consisting of an adjustable gate set along the ends of the ore defiectors and retarders sev cured upon the ore detiectors and extending part of the way between the gates for retarding the movement of the mass on the ore hed 'and directing vthe gangue into the space ends of the retardrs -while the ore is drawn off from the bottom of the bed beneath the outer gate.

14. In a dry ore separator, a table pro-` vided with a mesh, means for forcing a c onstant current of` air through themeslnmeans for imparting motion to the table, means for partially separating the 'greater partici` the gangne from the ore on one side of the table, a. plurality of gates adapted to be adjusted t'o near the mesh on the table to partially arrest the speed of,` the movement of the mass and divide the table substantially lengthwise under which the 'partially separatedmass is vdelivered to the opposite side of the table, andf means inclut ng a. gate adapted to be4 adjusted to the mesh 'on the table and set at the end of the ore detiectors for forming and maintaining an ore concentrating bed from the partlally separa-ted ore as it is delivered from one division of the table under the dividing gates upon the concentrating bed.

15. In a dry ore separator, a table provided with a mesh, means for forcing a constant current of air through the mesh, diagonally disposed ow. deflectors on the mesh,

means for imparting a reciprocating motion on the bed between the inner gate and the Y to the table, a gate dividing the table suhstantiallylengthwise, a gate at the end of the defiectors ada ted to be adjusted to Acontact with the' mes 1, and retarders extending from the outer gate across the deflectors to near the inner gate to direct the movement Aot the gangue on the bed into the space between the ends of' the retarders and the inner gate.

1G. In a dry ore separator, a table provided with a mesh, ore detlectors upon the tahle diagonally dls osed to the length of the table, gangue de ectors set upon the ore deflectors at an angle thereto and at an angle ,to the length of thevtable, means -for im- )arting motion to the table, means for forcing a current of air through the mesh on the table, a plurality of gates set upon the ore defiectors at an angle thereto, a gate set at an end of the ore deflectors and at an angle thereto for forming an ore concentrating gangue de ect-,ors upon the ore detiectors and at an angle thereto and'at an an le to the length O'thei'able, a gate upon't e ore de.

tiectors at an angle thereto an@ disposed lengthwise of the table, rmeans for adjusting the gate upward and downward, a gate at the end of the ore deilectors, and means for adjustin the gate to contact .with the mesh on the' ied for retarding and arrest'no the movement of the mass tobe separated between the gates to form an ore conceutratstant current of air through the mesh, means for ilnpartin a reciprocating motion to the table, ore de ectors upon the mesh set at an angle to the length of the table, a gate di viding the -table substantially lengthwise near the middle, gangue detlectors set upon the orexdeflectors and at an angle thereto and at an angle to the length of tne bed on one side 0f the dividing gate, means for forming :fn independent ore concentrating bed on the opposite side of the gate, and means fordecreasing .the rate of speed of the upper portion of the mass over the'ore concentratinr bed.

19. In'a dai-y ore separator, a table provided with a mesh, means for i' n' ing a constant current of air up through the mesh, means for imparting motion to the table, ore

deflectors upon the mesh set at au angle t;

the length of the table, gangue deflectors set upon the ore defiectors at an angle there1 -to and at an angle to the length of` the table adapted to force the greater part of the gan fue vfrom otfthe ore upon one division of tie table, a gate dividing the table sub' stantially lengthwise and adapted tobe adA justed vertically', means for arresting the movement of the mass to form a concentrating b ed on another division of the table, and means for directing the movement of the gangue from oti the separated ore.

20.1In a dry-ore separator, a table suspended at an incline both laterally and longitudinally and provided with a mesh thereon` means for imparting motion to th'e table` means 'for forcing` air through the mesh, a plurality1 et gates adapted to be adjusted upward and downward dividing the table subst antiaily lengthwise near the center, means including ore and gangue deiectors set at an angle to the motion of the table and at an angle to each other for forcing )art of the A angue from` off the ore on one division of t e table, meansfor forming' an ore concentrating' bed on the other division of the table including a gate at the end ot' the ore detlectors and retarders set over the ore deflectors and at an angle thereto.

21. In a dry ore separator, an air box, grate bars above the air box, 'a mesh upon the grate bars, a mesh beneath the grate bars yin the, air box, means for forcing the air through the mesh above and below the grate bars, means "for imparting motion to the table, a gate for dividing the table longitudinally, means for removing part of the gangue on one division of the table, and means for formlng an ore concentrating hedon the other division of the table.

22. In a dry ore separator, an air box, a'

'i U motion to the table, agate dividing the n table substantially lengthwise, .means for adjusting the gate, means including ore and gangue deectorsvvset atrvanfangle to each otherand to the' motion'of the table vupon one division of the table for .partially separating the gangue from oft the ore, 'and means including an adjustable gate, ore deiiectors and retarders for forming and maintaining an ore concentrating bed at a predetermined thickness on the otherdivision of the table.

23. In a dryore separator, a table provided with a mesh, means for forcing a constant current of air through the mesh, means for imparting motion to the table, an adjustable gate dividing the table longitudi nelly, means for forming an ore concentrating bed on one divisori of the table including :1 gate at the outer side of the ore concentraing bed and means for forming a runf way at one side of said bed for conveying the gangue from oit the, oreconcentrating 24. in a dry ore separator, a table pli'ovided with a mesh, means for forcing a con stant current of air through themesh, means for'imparting motion to the table, an adjustable gate for dividing the table longiim the om, an @,jusiable gg@ disp-fsw? lengthwise @mess th Lbke vdinghe faafu, gamglze deecors n @ne division .ar me tubi@ fof Partialy swarming he? ganan@ from o me ore, and means on ma 0% er' division of tha table incurng amd we de fie-eters and :un adjusbe gate at she @ad @f the @re deectors for fmfmmg and mjainin presence @if two wtnessas. WLLMl/ W. BUNSN. I Wlnesses: M. M. GABY, I E, M. www.

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