US3269538A - Concentrating table for mineral recovery - Google Patents

Description

Aug. 30, 1966 J. STEPHAN CONCENTRATING TABLE FOR MINERAL RECOVERY 2 Sheets-Sheet 1 Filed May 7, 1963 NFU INVENTOR. STEP/MN I ArraeA/Evs.

Aug. 30, 1966 J. STEPHAN 3,269,53g

CONCENTRATING TABLE FOR MINERAL RECOVERY Filed May 7, 1963 2 Sheets-Sheet 2 INVENTOR. ZIOSEPH $7'EPHA7A/ 147' TGEWE Y5- United States Patent 3,269,538 CQNQENTRATENG TABLE MINERAL RECOVERY doseph Stephan, fiahersiield, alili (P263. Box 695, Apache function, Ariz. aszza Fitted May 7, 1963, Ser. No. 278,679 iii-aims. (U. 29-d41) This invention relates generally to apparatus for recovery of minerals, and more specifically is directed to a novel table having a downwardly inclined bed of unique construction, and means for cyclically imparting to the bed a vibratory reciprocating longitudinal movement of small magnitude but of relatively high frequency, of the order of 750 cycles per minute. The apparatus is applicable for use with milled ore, placer material and continuous ejection of concentrates.

In accordance with a preferred embodiment of the invention hereinafter described and illustrated in detail, there is provided a horizontal base of generally rectangular rigid construction carried by a supporting framework adapted to rest on the ground or other surface. Above the base and substantially coextensive therewith is a horizontally disposed cradle movably supported by the base by means such as link arms permitting rapid cyclic vibratory longitudinal movement of the cradle relative to the base. A generally rectangular pan frame, substantially coextensive with the cradle or somewhat larger than the latter, is pivotally connected at its one end to the cradle about a horizontal axis and means are provided for elevating its other end at a selectively adjustable distance above the cradle, whereby the pan frame can be positioned at any desired inclination to the horizontal within a range of or thereabouts. However, conventional operation of the apparatus in accordance with the invention will more frequently involve an upward inclination of the pan frame from its pivotal connection with the cradle of between about 8 and 15.

The pan frame includes a rectangular bed having side walls and the distal end wall extending upwardly fro-m the bed a suitable distance such as 6 or 8 inches. The end wall at the pivoted end of the bed may be lower extending upwardly from the bed only two or three inches and constituting an overflow flange for tailings and other waste. At the distal end of the pan frame, where material to be treated is introduced, water supply means are provided. The means for imparting vibratory motion to the cradle and thus to the pan frame desirably include a rotatable cam journaled to the base and having a surface which is an interrupted portion of a spiral bearing against a cylindrical roller or the like rotatably journaled on the cradle. Resilient means are provided for strongly biasing the cradle roller into contact with the spiral cam surface, and the interruption in the latter imparts a cyclic jarring movement to the cradle.

The novel configuration of the pan frame bed, downwardly from the washing means at the distal end, includes a series of elements extending generally transversely of the bed and having a saw tooth upper contour as seen in vertical section. Each element is desirably upwardly concave throughout its length, the portion of the element midway between the pan frame side walls being slightly lower than the ends of the elements adjacent said side walls. The vertical surfaces of the saw tooth contour face downstream, and the rapid jar or jolt of the cradle during its movement cycle displaces the vertical surfaces in the upstream direction whereby the higher specific gravity items tend to remain close to the vertical faces while the lower specific gravity waste tends to move downwardly along the length of the bed.

The elements forming the bed are slightly inclined to 'ice a perpendicular to the length of the pan frame, so that concentrates tend to move toward the ends of the elements further downstream. The elements at those ends stop one half inch or so short of the pan frame side wall, exposing the underlying smooth surface of the bed floor and constituting a longitudinal channel along the bottom of said side wall. Means are provided for selectively blocking said channel, desirably in the form of bars fitting snugly in the channel and extending upwardly well above the bed elements.

At one corner of the lower end of the bed is an outlet through the bed floor for discharging the concentrates into a suitable receptacle, and a darn extends across the approach to the outlet to prevent any of the waste material from entering the outlet with the concentrates. At the other corner of the lower end of the bed there may be provided another outlet in the bed floor, preferably smaller than the first mentioned outlet, for receiving concentrates of intermediate specific gravity and discharging the same into a suitable container or receptacle benea-th the bed.

In operation, the present table virtually eliminates the packing of mud, clay or slime, as has been true with prior concentrating tables, and operates with a minimum of water.

Accordingly it is a principal object of the present invention to provide a novel vibrating table for concentrating minerals, either milled ore or placer. Other objects are to provide in such a table a bed having an upper contour, as seen in longitudinal vertical section, of a series of saw teeth having gently rising upper faces and sharply falling, downwardly directed, vertical faces; to provide such a bed made up of a series of elements extending generally transversely of the direction of material movement; to provide, in such a bed, a smooth narrow channel along one side of the bed, and removable means for selectively blocking the channel; to provide elements forming such a bed wherein the elements are concave upwardly throughout their extent; to provide in such a table means for imparting a periodic sharp jar or jolt to the bed in an upstream direction; and for allied and additional objects and purposes as will become clear from the following description of a preferred embodiment of the invention taken in connection with the accompanying drawings, in which:

FIG. 1 is a side elevational view of a concentrating table in accordance with the present invention, the bed being shown elevated by an angle of a few degrees.

FIG. 2 is a plan view of the bed of the device of FIG. 1.

FIG. 3 is a fragmentary sectional view taken on the arrows III-III of FIG. 2.

FIG. 4 is a transverse sectional view of one of the elements of the bed taken on arrows IVIV of FIG. 2.

FIG. 5 is a fragmentary view taken on arrows V--V of FIG. 1 showing a preferred form of the vibratory motion imparting means in accordance with the invention.

FIG. 6 is a sectional view taken on the arrows VI-VI of FIG. 5 showing the cam having an interrupted spiral surflace and the cylindrical roller in rolling contact therewit Referring now in detail to the drawings, a concentrating table for mineral recovery in accordance with the present invention is seen in FIG. 1 and includes a generally horizontally disposed rectangular base indicated generally at 8 and including parallel side members It and 12 (see FIG. 5) joined by transverse end members 11 and 13. The base is supported by a suitable substructure including upright members 7 of adequate strength and rigidity. Overlying the base and generally coextensive therewith is a rectangular cradle indicated generally at 15, having a pair of laterally spaced longitudinal side members 16 and 155 (see FIG. joined by transverse end members 17 and 19. Cradle is supported by the base for limited longitudinal movement relative to the base, the support means in the present illustrative form of the invention including generally vertically disposed links, of which two are seen in FIG. 1 and are indicated generally at 20 and 22. It will be understood that a similar pair of links are located on the opposite side of the base and cradle, there being one link joining each corresponding corner of the cradle and base. Link 211 is pivotally attached at its upper end to a stub shaft 23 carried by the cradle longitudinal side member 16 and extending outwardly therefrom, while the lower end of link 20 is pivotally connected to a stub shaft 24 carried by the base longitudinal side member 10 and extending outwardly therefrom. Link 22 is similarly pivotally connected at its upper end to a stub shaft 25 carried by and projecting outwardly from the cradle longitudinal side member 16, and is pivotally connected at its lower end to a stub shaft 26 carried by and extending outwardly from the base longitudinal side member 10.

Means are provided for biasing the cradle 15 rightwardly as seen in FIG. 1 relative to the base, and desirably such means are adjustable as to biasing force. The present illustrative form of the invention includes a laterally spaced pair of such means, one being indicated generally at 28 and including a heavy coil spring 30 abutting at its left end an angle plate 32 fixed to the base side member 10 and at its right end bearing against a collar 34 carried on the shank of a bolt 36 threaded through an aperture of a downwardly depending flange fixed to the cradle side member 16, with nuts 39 and 4t) threaded on the shank of bolt 36 and jammable against the flange 38 to lock the bolt in a selected position.

Means are provided for imparting a cyclical reciprocating or vibratory motion to the cradle 15 relative to the base. A preferred form of such means is best seen in FIGS. 5 and 6. As there appears, a shaft 4-0 is journaled in the cradle side members 16 and 18, and the shaft carries thereon a pair of cylindrical discs 42 and 44 spaced axially of the shaft, relatively close to the respective cradle side members 16 and 18. A second shaft indicated generally at similarly extends transversely of the table, but is journaled in pillow blocks or the like 62 and 64 fixed to the frame longitudinal members 111 and 12 respectively. The shaft 60 extends through enlarged openings 71 and 72 in the cradle side members 16 and 18, and does not touch either of said latter named members during any permissible excursion of the cradle.

A pan table indicated generally at is pivotally connected about a horizontal transverse axis 72 to one end of cradle 15. At the opposite or distal end, means indicated generally at 74 are provided for elevating such distal end of the pan table to a desired height, in order to give the pan table the optimum inclination for the particular material being treated. In the present embodiment such means include a pair of laterally spaced arcuate arms fixed to the pan table adjacent its distal end and extending generally downwardly therefrom, one of such arms being indicated at 75 and provided with a series of spaced teeth 76 separated by grooves 77. A locking crossbar 78 may be received in a selected pair of grooves, the crossbar resting on the cradle members 16 and 18.

Means are provided for rotating shaft 611 as through a belt and sheave indicated generally at 80, and the shaft carries fixed thereon a pair of cam members 82 and 34, adjacent the cradle side members 16 and 18 respectively. The outer surfaces of cam members 82 and 84 are in contact with the respective cylindrical discs 42 and 44 on shaft 40, the parts being biased into contact by the spring means 28 heretofore described.

As best seen in FIG. 6, the outer surface of the cam member 82 (84 being identical thereto) consists of a spiral interrupted by a radial shoulder 92 extending between the minimum radius of the spiral and the maximum radius thereof. The power means applied to the shaft 60, as through sheave 80, is adapted to rotate shaft 60 clockwise as seen in FIG. 6. Keeping in mind that the axis of the shaft 60 is fixed relative to the frame of the table, it will be understood that rotation of the earns 82 and 84 caused by rotation of shaft 64) causes a relatively slow leftward movement of discs 42 and 44, and thereby of shaft 41 and cradle 15, followed by a sharp rightward jarring movement when the shoulder 92 of cam 82 passes disc 42. Such rapid jarring or jolting movement results from the force of the resilient means 28 at the other end of the table heretofore described. Buffer means may be provided to soften the sharpness of such movement to the degree desired, an illustrative form of such means being indicated generally at 91 and including a coil spring 93 biasing the cradle leftwardly as seen in the drawing by an adjustable force controlled by bolt 94.

With reference now to FIGS. 2, 3 and 4, the bed of pan table 71) is preferably made up of a number of adjacent strip elements extending from one side wall 11M), and terminating close to the other side wall 1112, thereby leaving a relatively smooth surface channel along said side wall 102. Each strip element is fixed to the pan table floor 1116 as by rivets 111 or the like and includes a generally vertical surface 112 facing toward the lower pivoted end of the pan table, as well as a. smooth inclined surface 114 upstream of said vertical surface. During vibratory movement of the pan table as previously described, at a cyclic rate in the neighborhood of 750 cycles per minute, the particles of lower specific gravity tend to move downstream of the pan table, while the valuable concentrates of relatively high specific gravity tend to remain on the surface 114 of one element, adjacent the vertical surface 112 of the upstream element. Such heavy concentrates tend also to move toward side wall 102, because the strip elements 111 are inclined at a small anglepreferably between about 4 and about 12to the perpendicular to the axis of movement of pan table 71). It will be noted that such inclination is downwardly of the inclined pan table from side wall 1% toward side wall 102, and it will be further noted, as seen in FIG. 4, that the strip elements may be slightly higher at their ends adjacent side wall 1% than at their opposite ends, adjacent side wall 102.

FIG. 4 also shows the slight upward concavity of the upper surfaces of strip elements 110 throughout their length, thus tending to channel the main downward fiow of material generally centrally of the width of the pan table under the influence of water 115 sprayed from the water supply means indicated generally at 116 in FIGS. 1 and 2 mounted above the distal end portion of the pan table.

As previously mentioned, strip elements 110 do not extend to side wall 1112, but are spaced therefrom, leaving a smooth surface channel 197 immediately adjacent side wall 1112. In the upper portion of the table, immediately downstream of water source 116, the channel 1117 is blocked by a removable closure bar 118 of metal or other suitable material extending across the ends of the upper few strip elements, and a second and preferably longer such closure bar 119 blocks channel 1117 across the ends of most of the remaining downstream strip elements, as seen in FIG. 2. Each closure bar is held in place by suitable fastening means such as one or more bolts 120 extending through openings in side wall 102. An upstanding diverter strip 122 may be fixedly mounted on the floor 106 as by welding, extending angularly downwardly and inwardly from the lower portion of closure bar 118, and a dam 124, fixed to floor 1% and projecting upwardly therefrom, may extend at a generally similar angle from the lower portion of closure bar 119 to lower end wall 103 preventing tailings and other waste material from access to opening 104 leading downwardly to outlet 105 for the concentrates. Thus fixed strip 122 and dam 124 assist in channeling the waste material over the end wall 108, which is desirably of lower height than side walls 100 and 102 of the pan table.

In operation, a supply of material to be classified such as milled ore, placer or the like is placed upon the upper portion of the pan table under water source 116. Flow downwardly along the bed across the successive saw tooth surfaces of strip elements 110 will result from the vibratory motion imparted to the cradle and pan table as previously described. The unusual characteristic of such motion, in combination with the saw tooth surface of the bed, creates extremely effective classification by specific gravity of the particles of material being treated. The particles of relatively high specific gravity including the valuable material, tend to stay very close to the vertical surfaces of the successive saw teeth, While the particles of low specific gravity are washed over the successive saw teeth generally downwardly of the bed. Moreover, 'because of the slight inclination of the vertical surfaces of the saw teeth relative to the perpendicular to the longitudinal axis of the bed, the particles of high specific gravity are urged toward the side wall 102, and are prevented from entering the channel 107 adjacent said side wall by reason of the presence of the closure bars heretofore described. Thus, after a desired run has been completed, with the tailings and other wastes going over the lower end of the bed, the bars may be removed, whereby to permit the concentrates adjacent said bars to flow downwardly in the channel 107 to the opening 104 at the lower end of the table, and through the outlet 105 into any desired collecting vessel mounted therebelow.

Modifications and changes from the preferred form of the invention heretofore described and illustrated are Within my contemplation, and all such modifications and changes not departing from the spirit of the invention are intended to be embraced within the scope of the appended claims.

I claim:

1. A concentrating table for mineral recovery comprising:

a pan table having a generally rectangular floor and a wall extending upwardly from the floor along one side thereof;

a bed on said floor spaced from said wall to define a channel extending longitudinally of the table floor adjacent said wall, said bed providing a series of surfaces substantially perpendicular to the table floor, extending generally transversely thereof and facing one end of the table floor, said surfaces being spaced apart longitudinally of the table fioor by smooth surfaces slightly inclined relative to the table floor and extending between the bottom of each of said perpendicular surfaces and the top of the perpendicular surface next closer to said table floor end;

said perpendicular surfaces being inclined slightly to the perpendicular to the longitudinal table axis whereby the ends of said perpendicular surfaces adjacent said channel are closer to said one table floor end than are opposite ends thereof, said one table floor end being horizontal;

means for supporting said table with its floor inclined at a selected angle upwardly from said one table floor end;

and means for imparting longitudinal vibratory motion to said table. 2. The invention as stated in claim 1 including removable closure means receivable in said channel for selectively blocking the same.

3. The invention as stated in claim 1 wherein the end of each of said smooth surfaces distant from said channel is spaced farther above the table floor than is the end adjacent the channel.

4. The invention as stated in claim 1 wherein said motion imparting means includes means for moving the table slowly toward said end and then rapidly away from said end.

5. In a concentrating table for mineral recovery, in combination:

a pan table including a flat floor and an elongated bed thereon, and having upstanding side and end walls;

cradle means for supporting said pan table, the pan table being pivotally attached to the cradle adjacent one end thereof for swinging about a horizontal axis, and including selectively adjustable means adjacent the other end of the pan table for positioning said other end at a desired height above the corresponding end of the cradle means;

said bed having, throughout at least the lower portion thereof, a cross sectional shape, as viewed in longitudinal vertical section, of saw teeth with substantially vertical surfaces facing the pivoted end of the pan table, said bed being made up of a plurality of generally transversely extending strip elements fixed to the pan table and extending from the abutting relation with one side wall of the pan table to a point spaced inwardly from the other side wall, thereby forming a channel adjacent said other side wall, and the upper surface of each element being concave upwardly, each element, at its end adjacent the channel, extending upwardly from the floor by a smaller distance than at the other end of the element;

and means for imparting to the cradle and thereby to the pan table a cyclical vibratory reciprocating motion including a relatively slow movement of the pan table and cradle in the direction of said pivoted end and a sudden movement in the opposite direction.

References Cited by the Examiner UNITED STATES PATENTS 163,104 5/1875 Pomeroy 209---437 2,496,025 1/ 1950 Stephen 209-441 3,108,950 10/1963 Buckley 209-466 HARRY B. THORNTON, Primary Examiner.

FRANK W. LUTTER, Examiner.

L. H. EATHERTON, Assistant Examiner.

Claims (1)

1. A CONCENTRATION TABLE FOR MINERAL RECOVERY COMPRISING: A PAN TABLE HAVING A GENERALLY RECTANGULAR FLOOR AND A WALL EXTENDING UPWARDLY FROM THE FLOOR ALONG ONE SIDE THEREOF; A BED ON SAID FLOOR SPACED FROM SAID WALL TO DEFINE A CHANNEL EXTENDING LONGITUDINALLY OF THE TABLE FLOOR ADJACENT SAID WALL, SAID BED PROVIDING A SERIES OF SURFACES SUBSTANTIALLY PERPENDICULAR TO THE TABLE FLOOR, EXTENDING GENERALLY TRANSVESELY THEREOF AND FACING ONE END OF THE TABLE FLOOR, SAID SURFACES BEING SPACED APART LONGITUDINALLY OF THE TABLE FLOOR BY SMOOTH SURFACES SLIGHTLY INCLINED RELATIVE TO THE TABLE FLOOR AND EXTENDING BETWEEN THE BOTTOM OF EACH OF SAID PERPENDICULAR SURFACES AND THE TOP OF THE PERPENDICULAR SURFACE NEXT CLOSURE TO SAID TABLE FLOOR END; SAID PERPENDICULAR SURFACES BEING INCLINED SLIGHTLY TO THE PERPENDICULAR TO THE LONGITUDINAL TABLE AXIS

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