US2072594A - Ore concentrating table - Google Patents

Description

March 2, 1937. c. F. HUTCHINGS- ORE CONCENTRATING TABLE Filed Nov. '7, 1934 2 Sheets-Sheet 1 5 mm TL H n ma E w H Y B ATTORNEYS.

Patented Mar. 2, 1937 UNITED STATES PATENT OFFICE 2.072.594 ORE CONCENTRATING TABLE Charles F. Butchings, San Francisco, Calif. Application November I, 1934, Serial No. 751,839

Clalms.

This invention relates to ore concentrators, and

the objects of the invention are to provide an improved construction in magnetically vibrated concentrating tables whereby greater eillciency and 5 eifectiveness may be obtained, and in a .simple rugged structure not liable to get out of order.

Other features and advantages of the invention will appear in the following description and accompanying drawings.

The drawings Brief description 5 My improved concentrator consists of a rifled oscillating doubly inclined table suspended or supported from a frame by means of double parallel ball-bearing bar construction at opposite long edges of thetable, preferably on slanted or angularly disposed links or arms connecting the upper and lower bars, which provide for flexibility of oscillating movement with minimum of friction, all in combination with a double coil magnetic solenoid drive energized alternately to pull in opposite directions, the change from one directional pull to the other being made from a point of neutrality in the energizing current, or the longitudinal axis of the sine curve of a low frequency A. C. current so as to obtain a quick building up of the operating energy in both directions to directly work in time with the rebound of the table against a pair of shock-absorbing springs. The slanted links or arms supporting the table for rapid oscillation are secured at opposite ends respectively to the upper and lower parallel bars, and which bars are in turn respectively rotatably mounted in ball bearings secured along the supporting frame above, and the opposite long edges of the table below, and all of which cooperate to make it possible to rapidly vibrate a large heavy table withoutv most of the energy being absorbed.

The table or platform The table i, which may be of any size,- though conveniently is about 4 x 19 feet, preferably constructed of wood for lightness. and covered with waterproof material such as a sheet of linoleum 2, is provided with a rail 3 along its lower edge to form a run-off water gutter for water and tailings and over which rail the linoleum extends as shown in Fig. 4. A shorter rail 4 is also provided along the upper edge of the table. The table is flat and is suspended in a manner to tip slightly downward toward an observer of Fig. 1, as well as downward toward the right-hand end of Fig. 1. A table of this size rigidly constructed will weigh about "15 to pounds. a

' The rifles Secured to the surface of the table is a series of shallow riiiles 5, preferably of metal, as aluminum. These riilles abut the rail 3 at their lower ends and extend transversely and angularly part way over the table at an angle of about 45 with their upper ends terminating on a line X-X runni from about the center of the left-hand end of the table to a point just below the upper right-hand corner of the table. These riiiies are preferably about 3/ 64ths of an inch thick by 54th inch wide and straight, and they are spaced about 1 or 2 inches apart. A second series of shorter riilies 8 of about r nd of an inch or less in thickness may be interposed in the first series and aligned with the upper ends thereof as shown, while at I and 8 at the extreme right-hand end of the table are a pair of V-shaped deflectors arranged so as to guide'tailings off below 1, concentrates between I and 8, and fine concentrates above 8. Considerable variation in shape and spacing of the riilles is permissible, but the arrangement shown has produced exceptionally good results.

The frame The frame of the machine is in two portionsan upper and a lower portion. The upper portion 9 which includes T iron members 9', extending transversely above the table and from which the table is suspended, as will later be described. This upper frame is pivoted at In along its lower long edge to a lower or sub frame ii so that its angle of tilt with respect to the lower long edge may be controlled, and to this end one or more screw jacks I! are mounted along a longitudinal member i I of the sub-frame in a manner to raiseor lower the upper edge of the upper frame, and in order to'lock the upper frame at any point of adjustment fixed brackets i3 are provided on the sub-frame having slots as at i4 to pass a long clamping bolt or rod l5 provided with nuts I! for clamping the brackets against the sides of the lower transverse members of the upper frame.

The lower portion or sub-frame ii is slanted turn secured to a foundation or floor 2| and the lower end after raising or lowering is clamped firmly to legs 22 which are slotted as at 23 for passage of the clamping bolt 24.

Table suspension The suspension of the table on its arms or links 3| is shown carried out by means of two pairs of parallel bars or shafts 25 and 26, the former being rotatably mounted in ball bearings 21 carried in brackets 28 secured to the under sides of overhead T iron frame members 9, and the latter rotatably mounted in ball bearings 29 carried in boxes 30 secured along the upper and lower margins of the table and displaced laterally from the upper bearings 21 a few inches so that the supporting links or arms 3i which join the upper and lower shafts will hang at an angle to the vertical substantially as shown in Fig. 3 so as to cause a slight upward throwing of the particles of ore and sand toward the upper margin of the table as the same is rapidly vibrated in a. transverse direction.

The links or arms 3i are here shown as bolts or rods passing through both shafts, and with nuts on both sides to afiordnice adjustment and looking in place, but of course maybe otherwise attached. Also to be noted is that while I show oscillatory drive The table is rapidly vibrated or oscillated on its pivotal arms 3| by means of a powerful solenoid 32 provided with two separate spaced windings 33, 34 operating alternately on a single iron core 35 firmly riveted to or otherwise mounted on a bronze or brass rod 36 in turn mounted in plain or axially movable ball bearings 31 supported in brackets 38 fixed at opposite ends of the solenoid so that the core will be centered and free to slide back and forth in the field windings. The solenoid assembly is all carried as a unit in a frame 39 firmly bolted to the side of upper frame 9. Threads are cut on both ends of the bronze rod 36 and wing nuts 46 and 41 are provided to adjust the core in the magnetic field and to limit its throw as will later be explained. Rod 36 is firmly coupled at 40 to a smaller rod 4| which extends entirely across under the table i through openings in the table braces I and is threaded at 42 through a metal plate secured to one of them as at 42' and provided with a handwheel 43 at its outer end for adjusting the angle of table suspending links 3i by screwing the table either way on threads 42. Rod 4| may be locked in adjusted position to the table frame i by means of a nut 44 threaded to the rod and provided with a long tubular neck or pipe collar 45. The adjustment of the table with respect to the links as just described does not alter the adjustment of the solenoid core 35 in its field windings as it simply revolves when the wheel is turned, and its longitudinal position is determined and limited in both directions by two pairs of large wing nuts 46, 41 threaded to rod 36 and which may be locked in any position along the rod so as to leave the desired operating space between the inner nut of each pair and the frames 33 and 9 respectively, and in both of which spaces a heavy coiled compression spring 46, 49 surrounds the rod to function as a shock absorber. The adjustment of nuts 46 and 41 is to be such as to allow free play to the core and only bring the springs into contact with the frame stop just before the end of the desired stroke. 'By the adjustments 43, 44, 46 and 41, any desired stroke in one direction relative to the other may be had.

Energizing of the magnets giving an alternating current of 8 cycles per second which is taken off by means of brushes 5|, 52 on rings 53, 54 in conjunction with a winged commutator or rectifier mounted on the generator shaft 56. This commutator is here shown as a cylinder with a wing-shaped conducting area 55 stepped in at opposite sides with insulating areas 55" and fitted with three brushes 51, 58, 59; as indicated. Fig. '6 shows the cylindrical surface of the commutator as flattened out, while Fig. 5 shows diagrammatically the wiring from the brushes and slip rings and connections to the two coils, the arrangement being such as to open the circuit to one coil just before closing it to the other coil at' the zero voltage point of the current curve, so that coil 33 will be energized by the half cycle 60 and coil, from the other half cycle 6| and thus each coil will draw the core 35 toward its center in alternation with practically instantaneous reversals of power, each coil of the solenoid receiving a' current pulsation at each revolution of the gen erator. A three-point condenser is preferably connected to the wing. commutator brushes as indicated at 62 to absorb current surge incident to magnet discharge. bumper springs iscarefully proportioned with respect to the weight of the table and frequency of the vibration.

With the above construction and electrical drive I am able to operate a ten foot table, weighing with its water and ore, about 90 pounds with less than 200rwatts current consumption, and get a sharp kick to throw the ore particles upward with instant dropping and return of the table beneaththem, which is vital to the success of a gold separator.

Nature of the vibratory movement I In adjusting the angle of the suspension links with the handwheel 43 the greater their lower The strength of the- AND Assummc souus.

ward or toward the solenoid and bring its weight against spring 43 leaving an open space 40' at the outer end of spring I. The first electric pulsation is in coil 34 causing the core 3! to push the table outward or toward the left. This movement closes space ll and creates a like space at end of opposite spring 40 which is maintained until coil 34 dies and coil 33 is energized, and whereupon the reversal of the direction of magnetic pull snaps the table back to its original position. During the fractional second of time elapsing during magnetic reversal there is an open space at spring I! and for this instant there is nothing supporting the weight of the table, and therefore when coil 33 takes hold, the gravity of the heavy unsupported table together with the sudden powerful pull of'the magnet, gives the table an instantaneous snap back to its original position, closing the gap at spring 49 and opening it at spring ll again as shown in Fig. 3.

In further explanation of the vibratory movement, referring to Fig. 3, the first pulsation of current in coil 34 moves the table to the left, the supporting links move in an are which gives the table a lift as well as a lateral movement to the left, and this lifting of the table adds to the gravity of the material giving it more of a tendency to stick to the table surface and move with it to the end of the magnetic stroke. The return movement, however, being in the nature of an instantaneous drop and side pull back to starting position, the material is, for an instant, left in suspension, and by the time it settles again onto the table surface, the table has completed its return movement and the heavy particles settle to an advanced position on the table, or further away from the magnet. Thus the concentrate moves steadily upward over the table in minute jumps, at a speed governed by the angularity of the links and the cycle speed.

The movement of light materials by means of carriers suspended on slanted links or arms is not new, but the application of this principle to the substantial weight of a concentrating table with its accompanying load of ore and water, has not been successfully accomplished until the development of my invention which supplies to this principle new and unusual characteristics of vibration as well as the necessary mechanical and electrical devices to attain the desired result.

, plied by any convenient manner to give a uniform flow over the table from along the upper long edge and also from the left-hand end, and the table being adiusted for about a three-inch side tip and about a seven-inch end tip, gives a diagonal flow of water across the table of about In the machine shown in the drawings the water is delivered in a thin sheet to the upper long margin of the table from a trough 63 slotted along one edge as at 64, supplied to the trough from a pipe 65 arranged above the trough and provided with a series of downwardly directed pet cocks 66, while a similar branch pipe 61 extends across the upper end of the table to feed water to it in a manner controlled by the adjustment of the cocks.

The finely divided ore material in liquid condition with water is fed constantly to the table as from a pipe 88 near the left-hand end of the table to at once spread out over the surface due to the vibration and rifle action.

Bilect oI-combination, water and vibration Vibration causes agitation of both ore and water over the entire surface of the table, the lighter materials owing to greater bulk and less gravity have tendency to float with the water stream which flows rapidly over rifiles at right angles. This light material is stirred to the surface where table kick" has minimum effect and is carried downwardto lower levels and to the tailings.

On the other hand the concentrates are heavy and of less bulk. They are lifted only a minute distance from the table surface by vibration and fall back quickly, consequently the heavy particles are more subject to table kick than to the water flow. The result is a persistent movement of concentrate over the linoleum surface toward the upper edge of the table; the rinles help shield the concentrates against the flow of water; there is less water movement between the riilies and close to the linoleum than on the surface of the water.

The magnetic vibration is of such characteristic that the concentrates stratify within a few seconds after falling upon the table.

Net result of operation is a visible ribbon of black concentrate traveling from head end of table, moving successively over top end of each riilie, finally delivering in several grades at tail end at 69 and Ill. The tailings are carried off the same end but lower portion II In considering my invention as above described it will be manifest that various modifications can be made without departing from the spirit of the invention and scope of the appended claims.

I therefore claim:

1. In apparatus of the character described, a substantially horizontally disposed concentrating table, a frame, a plurality of rigid table supporting links pivotally connected at opposite ends to the table and frame respectively, said links being similarly inclined at an angle relative to a vertical plane extending longitudinally of the table, a solenoid having a slidable core connected to said table for vibrating the same laterally, a pair of adjacent field coils surrounding the core, means for automatically energizing said coils alternately in rapid succession whereby the table is vibrated laterally, means for varying the length of movement of the core in either direction.

2. In a construction as defined in claim 1, means for varying the degree of inclination of the links relative to said vertical plane.

3. In apparatus of the character described, a substantially horizontally disposed concentrating table, a frame, a plurality of rigid table supporting links pivotally connected at opposite ends to the table and frame respectively, said links being similarly inclined at an angle relative to a vertical plane extending longitudinally of the table, a solenoid connected to the table arranged and adapted to vibrate said table in a direction sub stantially normal to the longitudinal axis of the table, means for varying the stroke of the solenoid and means for varying the degree of inclination of said links relative to said vertical plane.

4. In a construction as defined in claim 3, said last mentioned means being carried by the table.

5. In apparatus of the character described, an imperforate, elongated, concentrating table having a head end for receiving value bearing material and a tail end for discharge of tailings thereover, an upstanding ledge along one side of the table extending between the head and tail end thereof, a plurality of riiile bars on the table extending diagonally thereacross from the ledge in a direction toward the tail end. means for feeding water onto the table along the head end and side opposite the ledge, a stationary supporting frame, said table being disposed generally horizontally but elevated at the head end and side opposite the ledge relative to the tail end and side of the ledge respectively whereby water flowing over the table will be relatively deep along the ledge and of progressively less depth from the ledge toward the side opposite the ledge and whereby the riiiles will coact with the ledge to cause pools of substantially non-flowing water along the riiiies, supporting means connecting the table to said frame mounting said table for oscillating generally vertically and horizontally in a vertical plane at substantially right angles to the table and in an arcuate path of travel confined to one side only of a vertical line extending through the axis of the arc and from a lowermost position spaced from said line, lifting means arranged and adapted to intermittently move said table upwardly in said arcuate path of travel and to release said table at the upper end of the path for falling solely by gravity to the lowermost position free of the influence of said lifting means.

CHARLES F. HU'I'CHINGS.

Images