US2091620A - Gold washing machine - Google Patents

Description

Aug. 31, 1937. E. wlLLiAMs GOLD WASHING MACHINE Filed Nov. 1, 1953 3 Sheets-Sheet 1 Aug- 3.1, 1937? E. L.. WILLIAMSV GOLD WASHING MACHINE Filed Nov. 1. 1933 3 Sheets-Sheet 2 :IllUmmm!!!HHHHHHH!!HHHHHH!! fUzF/VE L. Mz. Mfrs,

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f l l Aug. 31, 1937. E. L. wlLLuAMs GOLD WASHING MACHINE Filed Nov. l, 1933 5 Sheets-Sheet 5 Patented Aug. 31, 1937 UNlTED STATES ATEN GFFIQE 14 Claims.

My invention is concerned generally with gravel-treating and gravel-cleaning machines and specically with apparatus intended and adapted for the recovery of gold, and especially 'fitted for tthe recovery of gold from very lowgrade placer deposits.

Among the objects of my invention are to produce a machine which will effectively handle in quantity material of a wide variety of sizes, which will break upagglomerated lumps, which will remove all lines adhering to the surfaces of larger particles, and which will effectively concentrate any gold occurringeither in the fines or as particles of larger size. Another object of my invenl5 tion is to produce such a machine which will be compact and durable and which can be operated at but slight expense.

More speciiic objects of my invention include that of producing an effective screening device 0 which will be self-cleaning. Still another specific object of my invention is to impart to the scrubbing and riflle tables over which passes the material being treated a peculiar movement that has been found to be very effective in aiding scrubbing and the settling outvof the rheavy gold particles. A further object of my invention is to make it possible to use the large quantity of water necessary for effective scrubbing and washing operations and then quickly to free the material being treated of all excess water so that the quantity remaining will be no more than that necessary to an effective concentration of gold particles by a suspension process. An additional object is to provide a trap of novel form for collecting gold particles, especially large nuggets in the material being treated.

In carrying out my invention, I provide a scrubbing table and a riiile table over which the material being treated successively passes. `These tables, in the small machine with which this application is primarily concerned, are rigidly interconnected in superposed relation and oppositely inclined, and mechanism is provided for imparting to'them reciprocation in both a vertical and in a horizontal transverse direction. On the upper surface of the scrubbing table I provide a number of upwardly extending elements which, in the reciprocation of the tables, are brought violently into Contact with the material being treated. This, aided by the action of water supplied in quantity, thoroughly scrubs the larger particles of gravel and breaks up any friable lumps.

At the lower end of the scrubbing table, the

material being treated passes over screens operation of the apparatus.

through which the nes and the bulk of the water pass on to the upper end of the riflie table. The riiile table embodies a longitudinal central channel and a series of riiiies inclined toward said channel. lighter material in suspension in the water but permits the gold to settle against the faces of the riies to be fed inwardly to the channel and to. pass downwardly along such channel to a concentrating well located at the lower end of the 1 rife table.

The accompanying drawings illustrate my invention: Fig. 1 is a Verticall section through the com-plete machine on the line I--I of Fig. 2; Fig. 2 is a plan view of the machine with parts thereof l `broken away on the line 2 2 of Fig. 1; Fig. 3 is an end elevation of the machine; Fig. 4 is a fragmental plan view of the lower end of the riie table; Fig. 5 is an isometric view of the scrubbing table and screens with parts thereof broken away, 2 and Fig. 6 is .an isometricview of the complete riiile table.

The machine illustrated in the drawings compises a frame Iii which may conveniently be mounted upon skids I I for ease in moving it over 2 the ground. Upon this frame is supported a source of power which is represented in the drawings as a small gasoline engine I2.

The moving parts of the machine include a pair of tables I5 and I6 over which the material 3 being treated successively passes. In the machine illustrated, where compactness is a prime object, the two tables I5 and It are disposed one above the other and oppositely inclined so that material discharged from the lower end of the upper table I5 will be received upon the upper end of the table IS. In addition, the two tables are rigidly interconnected as by means of bracing members I 1 so that they will move as a unit in the At the upper end of the upper table I5 there may beplaced a small hopper It adapted to receive the material being treated. Immediately below this hopper I provide a relatively largemesh screen or grizzly I 9 adapted quickly to sepaarate large stones and similar objects. These large stones or other objects, failing to pass through the openings in the grizzly I9, fall down an inclined plate 29 and are discharged.

The finer material passing through the grizzly 5 falls upon the upper end of the able I 5 which, over the area below the grizzly, is provided with a series of upwardly extending projections 2 I, coni veniently hemispherical in shape. As the table `I 5 is agitated by the mechanism to be hereinafter' 5 The agitation of the riiile table keeps 5 described, these projections 2| tend to break up the agglomerated lumps of material and to dislodge nes which adhere to the surfaces of large particles.

Immediately below the area covered by the projections 2I, the tabley I5 is provided with a series of rows of inclined baiiles 22, adjacent rows of such baffles being oppositely inclined. Conveniently, each of these baffles is formed of a short piece of angle iron one flange of which is secured, as by welding, to the upper face of the table I5, while the other flange extends generally upwardly in a plane perpendicular to the face of the table. Desirably, the upper ends of the generally vertical flanges of the baffles 22 are sharpened so as to exercise a cutting action upon the material passing through the bafes, thus serving further to break up agglomerated lumps and remove nes adhering to the larger solid pieces.

The action of the projections 2I and baffles 22 in breaking up lumps of agglomerated material and removing fines from the surfaces of larger solid pieces is augmented by the action of water discharged through a spray pipe 23 that extends across the upper open end of the hopper I8.

Beyond that area of the table I5 which is covered by the bales 22 I provide in the table a series of openings which form in effect a screen serving to separate comparatively large pieces of material from the remainder. If considered desirable, the action of the screen provided by the holes 25 may be supplemented by an auxiliary screen 26 placed beneath and parallel to the screen 25 and having openings of smaller size.

Below the openings 25 in the table I5, and below the auxiliary screen 26 if such an auxiliary screen is used, I provide an inclined plate 2l which serves to carry to the upper end of the table I6 all material falling through the openings in the screen or screens. As is clear from Fig. l, the table I5 and the auxiliary screen 26 extend beyond the upper end of the table I5 so that the material which does not pass through the openings 25 and through the screen 26 will be discharged.

The material passing both screens is carried by the inclined plate 2l to the extreme top end of the table I6, falls upon such table, and tends to pass downwardly7 thereover under the iniluence of gravity. Further, a large part of the water discharged from the pipe 23 also passes through the screens 25 and 26 to be discharged upon the upper end of the table I6 upon which it is conned by side walls 28 and an end wall 29.

The table I6 is provided with a centrally disposed longitudinally extending channel SI which opens upwardly. The table is also provided with a series of bailles or riflies 32 which project upwardly from the face of the table I6 and extend generally transversely of such table.

Each of the riffles 32 has a central portion bridging the channel 3| and disposed at substantially right angles to the longitudinal center-line of the table and channel. At or about the side edges of the channel 3|, each of the riiiles 32 is bent through an angle approximately 16, the bent portions extending upwardly of the table I6. Near the upper end of the table I5, the riifles 32 extend from one side wall 28 to the other; but I have found it advisable, beginning about onethird the way down the table I6, to shorten the riiiies gradually and successively, as is clear from Fig. 6, until the last riflle 32 has a length equal to but a fraction of the width of the table I5.

At its extreme lower end, the channel 3l communicates with a well 35 having a removable bottom closure 36, the purpose of which will become evident hereinafter.

To confine the material entering the well 35 to that which flows downwardly in the channel 3|, I provide on each side of the channel below the lower rilile 32 an upwardly projecting plate 3l which extends downwardly of the table I5 from the lower rifl'le to a point beyond the open upper end of the well 35.

For the purpose of securing the desired movement of the two tables I5 and I6 I employ the mechanism shown in the drawings which includes two shafts I6 and 4I which are mounted for rotation in the frame Il) and which extend transversely of the tables I5 and I6. Upon each of these shafts I mount a pair of eccentric cams ft2 and 43 which are of equal diameter and similar eccentricity. From the lower table I6 I mount two transversely extending shafts and 45 each of which carries two rolls 47 and 4E! which rest upon the eccentric cylindrical surfaces of the cams 42 and 43 respectively. As is evident, ro tation of the two shafts 5B and 4I results in vertical reciprocation of the twotables I5 and I6.

I nd that Vertical reciprocation of the tables is not sufficient to give the best results, and I therefore provide means for causing the tables to reciprocate horizontally as well as vertically. 'Io this end, one of the cams on each of the shafts d@ and 5I, here shown as the cam 42, is provided with a groove lying in a plane oblique to the axis of the shaft with which the cam rotates and the corresponding roller 4l is provided with an outwardly projecting annular flange 5I which is received in the groovey 55. This is clear from Figs. 2 and 3.

The shafts 45 and 46 which are supported from the lower`table I 6 may project outwardly through vertical slots 53 in vertical members 54 on the frame of the machine to guide the tables. The shafts I5 and G6 are free to move longitudinally of themselves in the slots 53, so that neither horizontal reciprocation nor vertical reciprocation of the tables is interfered with.

For the purpose of driving the shafts 45 and 4I, each may be provided with a gear 60 which meshes with a common pinion 5I on the crank shaft of the engine I2.

rIhe eccentric cams 42 and 43 on the two shafts 40 and 4I are preferably set so that their eccentricities are corresponding so that each of the tables I5 and I 6 will always remain parallel to itself as it moves up and down. Each oblique groove 55 is so dispo-sed relative to the direction of eccentricity of the cam d2 that the tables reach the limit of their vertical movement at a time different from that at which they reach the limits of their horizontal movement. In other words, the vertical and horizontal reciprocatory movements of the tables are out of phase with each other; and as a result, the two tables I5 and I6 move in unison in a closed curved path located in a plane which is vertical and which extends transversely of the tables.

'Ihe agitation which is produced by the tablernovement above set forth has proven very effective for my purpose. The material falling through the grizzly I5 is severely agitated in contact with the projections I5 and baffles 22; and this agitation, supplemented by the action of water, very effectively breaks up all lumps of agglomerated material and removes the nes from the surface of large stones. In addition, the table agitation is very effective in the screen- 70 When a trap, such as the trap just described, is

ing by the holes 25 and the auxiliary screen 2B, the vertical reciprocation serving to prevent the buildingV up of-A an'accumulation of nne material around the edges of the screen openings. As a 5 result, vby the rtime the material reaches the lower end ofthe table I5 substantially all lines have been removed. and pass through the screens on toi-the upper end of the table I6 together with a large part of the Water discharged from the pipe 23.

Asthe' material passes: over the `table I6, the agitation thereof tends to cause all the heavier gold particles` to settle while maintaining the lighter nes in suspension. The gold particles separating out collect against the upper faces of the rillesy 32, work their way inwardly as the result of the slight inclination of suchrillles,` and eventually drop into the channel` 3I through which they pass to the Well 35.

Iny placer deposits, there frequently occur quantities of iron in the form known as black sand which is relatively heavy and apart at least of which may, by reason of its weight, 'lnd its way into the well 35. In the well 35, therefore, yI may place a quantity of mercury with which the gold will amalgamate leaving the iron-bearing black sand free. g

For the purpose of agitating the material in the well 35 I may support from the frame I0 a O transverse bar I0 which carrie-s a series of downwardly extending rods 1I that project into the well 35. As the bar lIIJ` is stationarily supported from the frameof the machine, and as the material in the well moves back and forth and up and down with the tables, the rods 'II violently agitate the contents of the well 35 and act as a stirring means. The resulting agitation brings all the gold particles intocontact with the mercury 36 and at the same time prevents the black sand 0 from settling and packing in the Well.

The particular arrangement of riles illustrated best in Fig. 6 has a very denite advantage.v In order to insure that all fines will be washed from the surface of larger particles it is essential that a large quantity of water be discharged from the vpipe 23. The quantity of water necessary for this purpose is far more than is necessary for the separating process carried out on the table I6. It is for this reason that the riles`32 near the lower end of the table I6 are made shorter, as free escape of water with the lighter iines around 4the ends of the shortened riffles is permitted.

I find it desirable to provide ahead of the screens and 26 a trap adapted to collect any nuggets of gold which may be in the material treated. One such trapis illustrated in Figs. 1 and 5 immediately above the holes 25 in the table I5. This trap lies below the plane of the table and extends completely across it. It has two side O Walls 'I5 disposed generally Vperpendicular to the table I5 and a bottom wall 'IB which is inclined to the horizontal in a direction opposite to the inclination of the table I5.

From the upper edge of the open upper end of the trap there extends a lip 'I'I. Conveniently, this lip is of a width approximately half that of the trap-opening. The upper surface of the lip is generally semicircular in cross-section, as is clear from Fig. 1.

located immediately below the inclined baies 22, I find it desirable to interpose between the last set of such baffles and the lip II a series of battles 'I8 which extend longitudinally of the table I5 5 and serve to straighten the direction of movementv ot the material' dischargedfromsthe bailles 22, thus eliminating any tendency of such material to collect at one side of the table I5.

With. atrap such as above described the water` passing generallyV downwardly' along the table I5l is elevated somewhat by the slope of the upstream face of the lip, 'I1 and then drops as it passes beyond the crestof the lip. As a result, the Water immediately above the trap opening has a downwardfcomponent of movement and some of it will enter the trap together with any fairly large sized gold particlesfreed by the scrubbing action to which thegravel `has beenr subjected. The direction of this, water entering the trap is in eiTect tangential to the body of water already in the trap so that such Water will be subjected to a whirling action. Relativelyheavyy gold particles will be deposited in the 'acuteangled corner between the bottom trap-wall 'I5 and the upper side wall 'I5 while particles of lighter material will be maintained in suspension and prevented from packing in the trap.

y If desired, one or more check-traps 80 may be provided at the lower end of the table I6 beyond the well to catch any gold particles which have escaped concentration. Such a trap will also serve to collect any floured mercury which escapes from the well 35 after having become suspended in finely divided statein the Water in the well. l

At the conclusion of operations, the machine is Stopped and gold is removed from the traps which may be 'provided with removable end-closures 82 for that purpose. 'I'he bottom-closure 3.6 of the well 35 is removed and the gold'amalgam drained from the well 35. The gold in the amalgam may be recovered by known methods which form no part vof my present invention.

I claim as my invention:

l. In mineral concentrating apparatus, an inclined table provided with a longitudinally extending channel, a series of rillles each extending transversely of said riffle table, each of said riffles having a central portion bridging said channel and end portions bent to extend obliquely upward on the table, the riflles near the upper end of the table extending substantially completely across it and those near the lower end of the table having a length less than the width of the table, and means for causing said table to reciprocate both horizontally and vertically.

2. In mineral concentrating apparatus, a longitudinally inclined table provided with a longitudinally extending channel, a series of riilles each extending transversely of said rile table, each of said riflles having a central portion bridging said channel and end portions bent to extend obliquely upward on the table, and means for causing said table to reciprocate both laterally and vertically.

3. In mineral concentrating apparatus, an inclined table provided with a longitudinally extending channel, a series of riflles each extending transversely of said rife table, each of said riilles having a central portion bridging said channel and end portions bent to extend obliquely outward from said channel and upward on the table, the riilles near the upper end of the table extending substantially completely across it and those near the lower end of the table having a length less than the width of the table, and means for agitating said table.

4. In mineral concentrating apparatus, an inclined table provided with a longitudinally extending channel, a series of rifles each extending transversely of said riile table, each of said riilles having a central portion bridging said channel and end portions bent to extend obliquely outward from said channel and upward on the table, the rifes near the upper end of the table extending substantially completely across it and those near the lower end of the table having a length less than the width of the table.

5. n mineral concentrating apparatus, a riffl table, a pair of rotatable, horizontally spaced, parallel eccentrics disposed adjacent said riffle table, said eccentrics being provided with peripheral grooves,l said grooves being continuous and having generally helical portions of opposite hand, means guiding said table for movement in a plane parallel to the axes of rotation of` said eccentrics, and rollers mounted on said table and received in said grooves.

6. The invention set forth in claim 5 with the addition that said riiiie table is' inclined in a plane substantially perpendicular to the axes of rotation of said eccentrics.

'7. In mineral concentrating apparatus, a table, means for causing mineral-bearing liquid to flow longitudinally over said table, said table having a longitudinally extending opening and below such opening a longitudinal trough, and a plurality o inclined baffles on the upper surface of said table inclined toward said trough in the direction of liquid-now.

8. The invention set forth in claim '7 with the addition that said trough is of substantially rectangular cross-section.

9. The invention set forth in claim with the addition of means for reciprocating said table in a plane transverse to the path of liquid-flow.

l0. In a device of the class described, a longitudinally inclined scrubbing table, a longitudinally inclined rife table positioned to receive material discharged from said scrubbing table, means conning each of said tables to movement in a vertical plane. which is transverse to the table, and means for causing each table to move in a closed curved path in such plane.

1l. In combination, means for scrubbing and Washing gravel, a longitudinally inclined riie table for receiving the washings from'said scrubbing and washing means, means conning said riiiie table to movement in a vertical plane which is transverse to said riiile table, and means for causing said rile table to move in a closed curved path in suchplane.

12. In mineral concentrating apparatus, a rifile table, eccentrics supporting said table, said eccentrics being disposed on horizontally spaced parallel aXes and rotatable about such axes to cause generally vertical reciprocation of said table, and provisions for reciprocating said table generally horizontally as it reciprocates vertically, said vertical and horizontal rcciprocation being at the same rate but out of phase with each other whereby said table is moved in a closed curved path.

13. In a mineral concentration apparatus, a riiiie table, mechanisms for reciprocating said table translationally intwo different directions in the same plane transverse to said table, said mechanisms producing respective reciprocations which are at the same rate but out of phase with each other whereby said table is moved in a closed curved path.`

i4. In mineral concentration apparatus, a rile table, mechanism for causing said table to move in a closed curved path in a plane transverse to the table, said table being provided with riiiies which are oblique to the plane in which the table is moved.

EUGENE L. WILLIAMS.

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