US2321514A - Separating process and apparatus - Google Patents

Description

June 8, 1943. J, w, p I 2,321,514

SEPARATING PROCESS AND APPARATUS Filed Aug. :5, 1940 s Sheets-Sheet 1 June 8, 1943. J. w. REED SEPARATING PROCESS AND APPARATUS Filed Aug-'. :5, 1940 s Sheets-Sheet 2 .LWFI ll. Illll June 8, 1943. A J. w. REED 2,321,514

SEPARATING PROCESS AND APPARATUS Filed Aug. :5, 1940 s Sheets-Sheet 5.

Jake/Z- eed Patented June 8, 1943 UNITED STATES PATENT- OFFICE 2,321,514 sEPaaA'rmo rnoosss AND APPARATllS Joseph w. Reed, Fairmont, W. Va. Application August 3, 1940, Serial No. 350,764

20 Claims.

The present invention relates to a process of and an apparatus for sizing and separating the sized fragments of crushed coal and like material or ores, and the primary object of the invention is to provide a novel process and apparatus capable of operation easily and with facility and having a large capacity for the fioor space occupied, and which is automatically adjustable in its operation while separating the material to plus and minus a desired or selected splitting specific gravity, whether material of such splitting specific gravity is present in the raw material or absent therefrom, and which is capable of performing such separation accurately and automatically during the feeding ofraw material varying over a wide range of sizes and grades, the present invention being an improvement upon the inventions disclosed in my prior Patent No. 2,014,291 granted September 10, 1935 and my copending application Ser. No. 267,862, filed April 14, 1939, now Patent No. 2,210,818

granted August 6, 1940.

process of and means for measuring, under standardized conditions, the specific gravity of an intermediate portion or layer of the stratifying bed, determining whether such intermediate portion of the bed is plus or minus the desired unselected specific gravity, and discharging the material according to such measurements.

.Another object is to provide a process of and an apparatus for maintaining a standardized condition of a mixture of fluid and material of the minus specific gravitie as an agitational standard of buoyancy for sinking the heavier material to an intermediate portion of the bed of material while measuring the specific gravity of such heavier material under such standard conditions in such intermediate portion.

Another object of the invention is to provide a process of and an apparatus for improving the accuracy of measurement of the specific gravity of the material in such intermediate portion of the bed of material undergoing separation by measuring the viscosity produced by the specific gravity of the material in a mixtureof a fluid and the material in such intermediate portion under such standard conditions of agitation.

A further object of the invention is to provide a processor and means for classifying or raduating the raw material as to size as the same is fed to the separating bed, thereby prov moting or facilitating the stratification and seprying out the presentinventionj Fig. 2is an elevation of the apparatus shown in Fig. 1, viewed from the right hand side o f Fig. 3 is a vertical section taken centrally through the separating apparatus Fig 4 is a horizontal section taken on the line 4- -4 inFig.3;-

v "Fig. 5 is a horizontal section taken on the line Fig.6 i's a horizontal section taken on the' line 66 in Fig. 3

i Fig.7 is a detail view of one of the vane driving devices;

Fig.8 is a detail vertical seotion'taken on the line 88 inFig.1;'

Fig. 9 is a detail vertical section taken on the line 9--9inFig.l; v I

Fig. 10 is a "detail vertical section, on an enlarged scale, taken on the line l0|l in Fig. 5; and V Fig. 11 is a detail view, partly in elevation and partly in section, of the controlling means for the central fluid discharge.

Similar parts are designated by the same reference characters in the difierent' figures.

The apparatus, as shown in the present instance, comprises a separating chamber l which is preferably of cylindrical form and open at the top. The upper and lower portions of the walls of this chamber are unper'forated, but the portion of the'wall intermediate of its height is'provided with annular rows of peripheral perforations 2 for the admission of fluid, as will be hereinafter described. A truncated cone 3 is fixed to and surrounds the lower portion of the separating chamber, this cone joining a short cylindrical wall 4 which supports within it a conical bottom 5 which is preferably perforated, as by the perforations 5, the lower end of the conical bottom discharging into a chute I which leads to a belt T or other disposal means for the heavier constituents separated from the material in the separating chamber.

The peripheral perforations 2 in the medial portion of the separating chamber are surrounded by a circular fluid duct 8 which supplies fluid to the interior of the chamber through the perforations 2, and this circular duct is provided with an inlet 9 to receive fluid, whch may be air or water, it being shown adaped in the present instance to supply air from a fan or blower I which may be driven continuously by an electric motor II which may be connected to the shaft I2 of the fan, and an interrupter I3, which may be in the form of a bladed device, is rotatable in the outlet M of the fan to provide impulses or pulsations of desired frequency in the air supplied to the duct 8. A valve I is interposed between the duct inlet 9 and the fan outlet for con trolling the flow of air to the separator, under the automatic control of means which will be hereinafter described. It will be understood of course that if water or other liquid is employed instead of air, any suitable pump may be employed to supply such liquid in place of the fan. In employing a fan for supplying air to the separating chamber, the fan intake duct l5 preferably receives air, through a suitable air filter H, from an exhaust air duct l8 which is closed at its lower end but may be provided with a removable manhole IQ for the removal of such dust as accumulates in the bottom of the duct l8.

The separating chamber is provided, near its upper end, with a discharge opening for the lighter constituents of the material, these lighter constituents overflowing through this opening into a chute 2| which preferably slopes downwardly to and discharges the lighter constituents onto a belt 22 or other suitable means of disposal. The upper portion of the chute 2| extends through the top of the air exhaust duct I8, and its sides are preferably perforated as indicated at 23 for the discharge of air therefrom into the exhaust duct l8. The discharge opening 20 for the lighter constituents is located at the elevation of the material retained in the separating chamber, and its lower edge 2|] preferably slopes upwardly toward the direction of material flow to gradually lower the surface of the material, by an overflow discharge, to maintain a desired thickness of material bed in the separating chamber. By perforating the walls of the chute 2| which extend through the air exhaust duct l8, such dust as may be removed from the separating chamber will be returned to the intake of the fan, thereby minimizing objectionable dust at the material discharge 1 and the outlet of the chute 2 I.

The lower portion of the separating chamber has a radial screen 25 fixed to the surrounding Wall of the separating chamber, and immediately below this screen a rotatable disk 26 is provided, this disk having a substantially triangular orifice 21 therein, and below the disk 26 is mounted a second radial screen 28 which is similar to the screen 25 and is fixed at its periphery to the surrounding wall of the separating chamber. A second rotatable disk 29 is mounted below the screen 28 and immediately below the lower edge of the surrounding wall of the separating chamber, and this disk is provided with a substantially triangular orifice 30 which isdiametrically opposite to the orifice 21 in the disk 26. The disks 2B and 29 are fixed at their centers to a hub 3| which is, in turn, fixed to the upper end of a hollow vertical shaft 32, and this hollow shaft has a worm wheel 33 fixed on its lower end, this worm wheel meshing with a worm 34 which is driven by a variable speed electric motor 35, the speed of this motor being varied by a rheostat or resistance 35 connected in its operating circuit and governed automatically by means which will be hereinafter described. Rotation of the disks 25 and 29 causes the heavier constituents of the material, descending through the radial screen 25, to fall through the orifice 21 in the upper disk and subsequently through the orifice 30 in the lower disk 29, these constituents being thus caused to descend downwardly, layer by layer, from the lower portion of the separating chamber into the conical bottom 5.

A set of rotatable vanes 35 are mounted concentrically in the separating chamber in the portion thereof intermediate its height and above the discharge means for its lower portion, these vanes being carried by a hub 36 to which they are preferably pivotally connected as at 31 to enable them to be adjusted to vary their downward slope. These vanes are rotated by a hollow vertical shaft 38 which extends upwardly through the central portion of the separating chamber and has the vane carrying hub 36 fixed thereto. The lower portion of the shaft 38 extends downwardly through the hollow shaft 32 and has a worm wheel 39 fixed to its lower end and a worm 4|] meshing with this worm wheel for driving it. The vanes 35 are preferably provided with baflles 4| of circular form and arranged concentrically within the separating chamber, for preventing eddy currents in the material in the upper portion of the separating chamber, as will be hereinafter described.

In the upper portion of the separating chamher and above the vanes 35 are mounted a set of upper vanes which are carried on a hub 46 which is fixed to the upper end of a shaft so that these vanes will rotate in a horizontal plane in the upper portion of the body of material in the separating chamber and below the upper discharge opening 20 for the upper portion of the body of material and above an intermediate portion of the body of material, and these upper vanes are also preferably provided with baflles 48 for preventing eddy currents in the body of material during agitation thereof by the air or the fluid. The balfles 48 are preferably circular and concentric with one another and with the cylindrical separating chamber, these baffles terminating at their upper edges substantially at the level of the surface of the material retained in the separating chamber and these vanes extending downwardly to the upper surface of the intermediate portion of the body of material in the separating chamber. The baffles 48 are preferably located at the inner and outer sides of the baffles 4| on the vanes 35, and the baffles 4| preferably terminate upwardly and downwardly at the upper and lower limits of the intermediate portion of the body of material in the separating chamber. The lower end of the shaft 4'! which rotates the upper vanes 45 has a worm wheel 49 fixed thereon, and this worm wheel meshes with a worm 5!! for driving it. The shaft 41 is mounted in a bearing 5| which may be supported on a cross member 52 of a suitable frame 53, the latter supporting the separating chamber and the other parts of the apparatus,

the separating chamber being shown mounted in this frame by supporting brackets 54. The hollow shafts 32 and 38 may be supported from the bearing by ball bearings 55, 5'3 and 51 which may be interposed between the bearing and the worm wheels, as shown in Fig. 3. In order to prevent dust from entering between the shafts 32 and 38 and thereby vary the resistance to the turning of these shafts and to also protect the bearings from dust, a packing box 58 is preferably provided between these shafts, and a similar packing box 59 i preferably provided between the shaft 32 and its supporting bearing 68 for a similar purpose. The upper end of the innermost shaft 4'! is preferably supported by a bearing 6| provided in a strap 62 which extends across the upper portion of the separating chamber and is fixed at its ends to the walls thereof.

A central air or other fluid discharge tube 65 is mounted concentrically within the separating chamber, it being supported at its lower end by the upper radial screen and at its upper end by a packing ring 66. This fluid discharge tube is provided, at different levels above the peripheral fluid inlet perforations 2 with annular hori-,

zontal rows of perforations 6'! for admitting fluid from the separating chamber into the tube 65, and a set of individually rotatable rings '68, one ring for each annular series of perforations '61, and having a series of perforations 68 therein corresponding with the respective series of perforations 6?, are mounted'on the upper end of the tube 55. The outer side of each ring is preferably surrounded by finely perforated metal rings or other suitable screens 18 which cover the openings therein and thereby restrict the passage of fine material with the fluid passing into the discharge tube. By this arrangement of perforations in the upper end of the discharge tube, and the correspondingly perforated and individually rotatable rings, the discharge of the air or other fluid from the separating chamber into the discharge tub may be regulated at the different elevations, the air or other buoyant fluid entering the peripheral perforations 2 in the surrounding wail of the separating chamber being caused to upwardly at more or less angle, as 1. idicated by the arrows in Fig. 3, according to the adjustments of the rings 58. The air or other fluid thus entering the tube discharges therefrom through its open lower end I i In addition to the air or fluid entering the separating chamber directly by the surrounding perforations it is preferable to employ a suitable number of radial fluid distributing tubes 15 which extend inwardly from the surrounding wall of the separating chamber to a cylindrical sleeve '55 to which they are fixed, this sleeve being imperforate so that it closes the inner ends of the tubes and is fixed on the fluid discharge tube 65. Each of the fluid distributing tube 15 has a substantially triangular top portion Tl the apex of which is directed upwardly and the sides of which are perforated as at 18 for the discharge of the fluid laterally therefrom. The portion of each distributing tube below its upper triangular portion has downwardly converging and imperforate side walls '19 the lower edges of which are spaced apart to provide a slot or opening in the bottom of the distributing tube for the discharge therefrom of any material entering the upper perforations in the tube, material resting against the converging imperforate walls 19 acting as an air seal to force the air out of the perforations in the upper triangular portion. The sides of the rating chamber.

upper triangular portion" preferably diminish in size or vertical height as they approach the central sleeve T6 in order to graduate the amount of fluid escaping from these distributing tubes at regular lateral intervals. By employing such radial fluid distributing tubes, a portion of the air entering the separating chamber through the peripheral perforations 2 enters the outer ends of the distributing tubes and flows inwardly therein, and the air is forced out of these tubes through the lateral perforations 78 into the surrounding material with a more or less horizontal impulse, as indicated by the arrows in Fig. 5, the upward flow of the air or other fluid being thereby distributed through the separating bed and uniformly modified centrally around the orbit of the circular separating chamber.

The more intense fluid agitation at the periphery of the body of material than at the center thereof due to the introduction of the air or fluid through the peripheral perforations 2 between the radial distributing tube 15 as well as through these tubes would, if not controlled, tend to flow the semi-liquefied mixture of material upwardly at the perimeter and downwardly at the center of the bed of material, thereby producing eddy currents which would be detrimental to stratiflcation and would tend to intermingle the graduated sizes of material fed into the separating chamber from the size classifier hereinafter described. Such detrimental eddy flow of material in the upper portion of the separating chamber is however prevented by the baflles 4| and-48 on the vanes 35 and 46 which obstruct a lateral or eddy flow of material while permitting the desired vertical agitation at the desired graduated intensities for the sizes. Also, eddy flow of the material below the vanes 35 may be prevented by adjusting the rings 68 controlling the fluid discharge into the discharge tube 65 and thereby varying the angles along which the fluid flows inwardly and diagonally upwardly from the peripheral fluid admission perforations 2. 1

The raw material is preferably fed to the sepa rating chamber by a size classifier. This size classifier comprises a feed hopper 8| which receives the raw material and discharges it through an outlet 82 by gravity into the size classifier 83. This size classifier comprises a substantially wedge shaped casing the front wall 84 of which is provided with perforations 85 for the admission of air or other fluid through a branch duct 86 leading from the fan outlet I4, and this classifier has a sloping roof 8? which is preferably perforated as shown, and a vertical inner or rear wall 88 which is also preferably perforated as shown. The remaining side walls 89 and bottom wall 98 of the classifier are preferably imperforate. One of the side walls 89 is provided with a discharge orifice 9| which is preferably substantially triangular in form, and this discharge orifice is controlled by a gate 92 for controlling the discharge of the sized raw material into the sepa- The flow of air or other fluid through the perforations 85 into the size classifier, under proper control of the air or fluid flow by a valve 93, flows the finer portions of thematerial from the interstices between the larger fragments of material, these smaller particles of the material being thereby caused to flow upwardly and inwardly under the sloping roof 81, the finer particles or fragments being intercepted by the perforated rear wall 88, and these finer particles intercepting the next larger sizes of particles, and so on, the larger fragments sinking forwardly into the voids created by removal of perimeter.

the fines and graduated sizesdiagonally upward from the coarsest to the finest, the air flow from the front to the rear wall of the classifier retaining the sizing as the sized material moves downwardly and out through the: bottom discharge orifice 9|, the raw material as thus sized being fed to the separating chamber. The discharge orifice 9| of the size classifier is located near the periphery of the separating chamber, and rotation of the material in the separating chamber distributes such sized material in concentric circles in the separating chamber.

The rate of feed of the sized raw material from the size classifier to the separating chamber is controlled by the gate 92 which is operated so as tofeed all sizes of the material uniformly and to compensate for the increasing circular area of the bed of material toward its The gate 92 is provided with means for operating it so that it will cause the sized material to flow from the size classifier at a rate which will restore the thickness of the retained bed of material in the upper portion of the separating chamber to replace that discharged therefrom by overflow through the discharge opening 20, thereby promoting separation of the material according to specific gravity. Such operating means consists preferably of a rotary magnet or electric motor 95 which is operatively connected to the shaft 96 on which the gate 92 is fixed, the operating circuit 9'| for this rotary magnet having connected therein a pair of brushes 9'! which are mounted in insulated relation on a supporting rod 99 and ride on the periphery of a commutator having a triangular metal segment 99 in its insulated cylindrical body I00. The commutator is rotated continuously in any suitable way, as by an electric motor which may be connected thereto asby a belt I02. The commutator is rotated at a desired rate of speed by the motor IOI and as the metal segment 99 of the commutator bridges the brushes 91 at each revolution of the commutator, the circuit through the magnet 95 is closed and .as the brushes pass on to the insulated portion of the commutator, the circuit of said magnet is opened. -The brushes 91 are slidable along the supporting rod 98, and by moving the brushes so that they will travel on a peripherally wider or narrower portion of the metal segment 99, the periods of time during which the gate 92 is open may be adjusted. The magnet 95, each time it is energized, will open the gate 92 to its full extent against a stop I03 whereby all sizes of material may flow at a maximum rate under control of the orifice 9| for such period, and the gate closes during the passage of the non-metallic or insulated portion of the commutator beneath the brushes 91. The rate of feed of the sized raw material and the uniform feeding thereof in the various sizes and desired volume and frequency i thus accomplished. A curved baflle plate I is preferably provided belowthe outlet orifice 9| of the size classifier at the elevation substantially of the surface a: of the material retained in the separating chamber; this baflle extending from the discharge orifice 9| to the discharge opening and radially from the center to the periphery of e differential casing facets-14 the-separating chamber to assist in retaining a depressed surface in the material'between the mate'rial entering the separating chamber from the orifice 9| distributes the material to the desired thickness. The baffie I05 is preferably perforated, as shown, to permit fluid to escape from thesurface of the material.

The shaft I06 of the worm 50 which rotates the upper vanes 45 is driven from a belt pulley I01 through a differential which comprises a casing |09 in' which a pair of planetary pinions I09 are'mounted, and a pair of master gears H0 and III fixed on the shaft I06 and the shaft II2 of thepulley I01 respectively. A strap H3 is fixed to the gear case I08, one end of this strap having a counterweight I I4 attached thereto, and the other end of this strap is attached to a lide II5 which is guided to move vertically, as the gear case I08 rotates, by a pair of guide rods H6. The slide H5 is connected to the lower end of a rod III which is connected to the air or fluid control valve I5 for operating it. Assuming power is applied to the pulley I01 to rotate the upper vanes 45, when the torque of operating these vanes and reacting through the I09 is greater than the counter-torque applied to this casing by the counterweight I I4, the counterweight rises, thereby operating the rod II! in a direction to open the air or fluid gate I5, thereby increasing the fluid agitation and correspondingly reducing the torque requiredto rotate the upper vanes 45, thus automatically adjusting the fluid flow to bring the torque required to rotate these vanes and the counter-torque applied by the counterweight II4 to equilibrium, thus establishing a standard torque at which the upper vanes rotate to maintain uniform fluid agitation in the upper portion of the body of material in the separating chamber. Increasing the value of the counterweight II4 reduces the intensity of fluid agitation maintained in the upper portion of the separating l differential having a strap I23 fixed thereto, one end of the strap I23 having a counterweight I24 connected thereto to' produce a countertorque on the gear case I22 to that transmitted therethrough to rotate the intermediate vane. A controller arm I25 is fixed to the strap I23 and is guided for vertical movement by a pair of guide rods I26. The controller arm I 25 carries an electrical contact I2'I to which one of the conductors for supplying operating current for the variable speed motor 35 is connected, this contact being movable over the resistance or rheostat 36 in consequence of vertical movements of the controller arm I25 and thereby vary the speed at which the motor 35 operates. By this arrangement, rotation of the drive pulley I2I connected to the master gear which drives the differential I22 transmits the torque of rotating the intermediate vanes 35 to the differential gear case I22, tending to cause this gear case to rotate and lift the weight I24 and thereby operate the contact I2'I to start or increase the speed of the motor 35, the downward discharge of the material in the separating chamber being thus regulated under control of the torque of rotating the vanes 35. By maintaining a standardized fluid flow through the body of material in the separating chamber, the torque required to rotate the vanes 35 measures the specific gravity of the material in which these vanes rotate, and the counterweight I24 is adjusted to a desired plitting specific gravity, thereby efifecting automatically discharge downwardly of all heavier material and retaining lighter material in the upper portion of the separating chamber. Increasing the value of the counterweight I24-increases the splitting specific gravity.

The differentials for th upper and lower vanes may be driven by a belt lfifi which connects the driving pulley i for driving the upper vanes to the pulley iii for driving the intermediate vanes, this belt causing th upper and intermediate vanes to thus rotate in the same direction, and both differentials may be driven by an electric motor I32 connected by a belt I33 to a driving pulley 134 fixed to the drive shaft of one of the differentials, as for example the drive shaft I35 for the driving master gear in the differential casing I22.

The construction and operation of the different elements of the apparatus having been hereinbefore described in detail, the general operation of th apparatus is as follows:

Assuming that the feed hopper 8i is full of raw material to be separated, that the motors H, 35, ml and I32 are in operation so that the vanes 35 and t5 are rotating and the fan H) is forcing air or fluid into the size classifier and the separating chamber, and that the central fluid discharges G8 are open, the fluid flow to the classifier is adjusted by the valve 93 to bring the raw material to graduated sizes before entering the separator. The raw material from the feed hopper flows by gravity to the size classifier and, under the action of the controlled flow of fluid into the classifier through the fluid inlet 85, floats the fines out of the interstices between the larger pieces, causing the fines to flow upwardly and inwardly under the sloping roof M. The finely perforated rear wall 88 of the classifier passes the fluid and intercepts the smaller fragments which, in turn, intercept the next larger size, and so on, while the larger fragments of the material sink forwardly into the voids created by removal of the fines and thereby graduate the sizes of the material from the largest, diagonally upwardly, to the smallest. The fluid flow to and through the perforated rear wall 88 of the classifier retains such size formation as the material moves downwardy and out through the bottom discharge orifice 9|, the sized raw material being fed to the separator under a flow which is controlled by the periodic opening of the gate 92 so that the surface of the material retained in the upper portion of the separating chamber is maintained substantially constant.

The flow of air or fluid entering the separator from the circular duct 8 through the peripheral perforations 2 in the cylindrical wall of the separating chamber flows partly toward the center of the separating chamber through the tubes 15 and distributed laterally through the perforations in the sides of these tubes and the remainder of this air or fluid entering the perforations 2 flows upwardly toward the center of the separating chamber with modified intensity. The sized raw material is fed from the classifier into the separating chamber on a radial line and onto the retained portion of the material in the separating chamber, the fines being located toward the center of the separating chamber and the coarser fragments toward the periphery thereof, and the raw material thus fed into the separating chamber fills the latter with concentric circles of sizes of material incident to the rotation of the vanes 45 and 35, with the fines toward the center and the larger fragments toward the periphery of the separating chamber, and this size formation is retained during separation by the flow of the air or fluid through the peripheral perforations 2 from the periphery toward the center of the separating chamber where such air or fluid discharges therefrom through the outlet tube 65, such fluid flow being of suflicient intensity to classify the sizes, thereby effecting reclassification of the material due to any degradation thereof incident to agitation of the material. By adjusting the perforated rings 68 on the upper portion of the central fluid discharge tube 65, the fluid flow into this discharge tube may be controlled so that the amount of air or fluid discharging centrally may be adjusted at any desired height, and the intensity of fluid flow centrally may be varied from a substantially horizontal flow to bring the fluid flow inward centrally to an intensity whereby the sizes of the material are classified and such sizing is maintained. The remaining portion of the fluid flowing upwardly is distributed centrally by theradial distributing tubes 15 which graduate the upward flow at regular intervals laterally, these distributors being disposed at regular intervals around the periphery of the separating chamber where the fluid enters, so that the upward floating portion of the fluid is distributed around the separating chamber and is uniformly modified in upward intensity concentrically to each concentric circle of sized material in the separating chamber, the fluid discharged from the perforations in the distributing tubes '55 being forced into the material between adjacent tubes with more or less horizontal impulses as such fluid curves into an upward distributed flow, the upward fluid flow being thereby distributed through the separating bed and uniformly modified centrally around the circular separating chamber.

The body of material in the separatingchamber rests upon the fixed radial screen 25 above the rotating discharge valve or disk 26, and the latter, as it rotates, slices off and discharges the bottom of the body of material, layer by layer, moving the material downwardly equilaterally and at a controlled rate in the form of a cylinder of material while the fluid floating upwardly through the material of different sizes stratifies similar sizes of material, with the heavier material moving downwardly. By thus disposing the sized material in concentric rings of sizes, and modifying the fluid flow to provide the proper buoyancy for each size ring, the layering of the light and heavy material of each size ring will be at similar positions, and the controlled equilateral descent of the cylinder of concentric sizes of material moves the heavy portion downwardly in all sizes, through a wide range of sizes of raw material.

A substantial thickness of bed of light material is retained in the upper portion of the body of material, the overflow discharge opening 20 being on a level with the surface of this retained bed of material, so that any excess light material on top of this bed will be discharged by overflow through the outlet 21! in controlled relation to the controlled downward discharge, such overflow discharge being the residue of the feed which is not discharged downwardly,

Control of the flow of fluid to the separator is governed automatically by the torque necessary to rotate the vanes 45 in the upper portion of the separating chamber below the discharge opening 20, such control being adjustable to maintain, by control of the fluid flow, a desired agitational standard of buoyancy in the upper portion of the body of material, and thereby a similarly regulated fluid flowthrough the intermediate and lower portions of the body of material in the separating chamber.

Control of the bottom discharge of the heavy constituents from the separating chamber is governed automatically by the torque necessary to rotate the vanes 35 in the intermediate portion of the body of material and above the discharge disks or. valves 26 and 29 for the heavy material, such control being adjusted to maintain by the controlled downward discharge a stratum of material substantially approximating the splitting specific gravity in the intermediate portion of the body of material in which these vanes rotate. The torque necessary to rotate the vanes 35 will be similar to that required to rotate the upper vanes 45 when the material in the intermediate and upper portions of the body are similar, since similar material will be similarly afiected by the standardized condition of buoyancy maintained by the upper vanes 45. When the specific gravity of the material in the intermediate portion of the body changes due to heavier material sinking into the intermediate portion the torque necessary to rotate the vanes 35 will increase, it becoming greater and greater as the specific gravity of the material in which these vanes rotate increases, and the heavier, less buoyant material settles into a more or less compact mass under the standardized condition of buoyancy which is maintained. Increase of torque required to rotate the vanes 35 beyond the standard fixed torque governs the operation of the lower discharge valves or disks 26 and 29, causing the heavy material in the intermediate portion of the separating chamber to descend, wherea a decrease in the torque required to rotate the vanes 35 below such standard torque stops downward discharge and prevents light material from escaping downwardly. When such operation of the lower discharge means by increasing the torque required to rotate the vanes 35 i produced by a mixture of very heavy and light material, producing a resultant torque greater than that required to rotate these vanes in material at the desired splitting specific gravity, downward discharge of the material moves the very heavy material below the vanes and reduces the torque required to rotate them, as the residue is only light material and stops the downward discharge. Therefore, when the intermediate splitting rate of material is absent, intermittent downward discharge lowers all material heavier than that of the desired or selected splitting specific gravity.

It is therefore possible to split material plus and minus a fixed specific gravity splitting point, whether or not material representative of such specific gravity is present or absent, all material heavier than the desired or selected splitting point passing downwardly, and all lighter material accumulating in the upper portion of the separating chamber and overflowing therefrom through the discharge opening 20 .for surplus light material.

When there is no light material in the entering raw material, a suflicient upper bed of light material previously introduced i retained below the discharge opening 20 to act as a sinking buoyancy for the heavier material, and such material is discharged downwardly at its entering rate while retaining suchsurface portion of the prior light material, v r

When there is no heavy material in the raw material enteringthe separator, the downward discharge ceases, the prior or existing bottom bed of heavy material being retained as a floating buoyancy for the light material, and such entering lightmaterial is discharged, it overflowing at the entering rate from the overflow discharge opening 20 for the surplus upper portion of light material.

The torque controls for the rotating vanes 45 and 35 respectively govern automatically the fluid flow and the downward discharge of the heavier material. When the torque required to rotate the vanes exceeds the counterweight torque, the differential gear case rotates, lifting its weight and operating the control which in turn reduces the torque required to rotate the vanes, bringing the driving torque into equilibrium with the counterweight torque at which standard torque such vanes rotate. By increasing the counterweight II4, the maintained agitation by fluid is decreased, and by increasing the counterweight I24 controlling the downward discharge, the splitting specific gravity maintained is increased.

The counterweights H4 and I24 are adjustable to maintain the desired standardized condition by:

(1) Automatic control of fluid flow maintaining a standardized condition in the upper portion of a mixture of fluid and material of the minus specific gravities at an agitational standard of buoyancy which sinks the heavier material to an intermediate portion of the body of material while measuring the specific gravity of such sinking material under such standard conditions in the intermediate portion of the body of material being separated.

(2).'Measuring the specific gravity of the material in such intermediate portion of the body by measuring the viscosity produced by the specific'gravity of the material in a fluid and material mixture in the intermediate portion of the body under such standard conditions of agitation and discharging the material accordin to such measurements.

(3) Automatically determining by such stand-V ardized measurements whether such separated material is plus or minus a desired splitting specific gravity and automatically discharging such material according to such measurements, removing the plus specific gravities downwardly and overflowing the minus specific gravities from the upper surface and retaining an upper portion of minus specific gravities and a lower portion of plus specific gravities as the sinking and floating buoyancies in and. between which said standardized conditions by controlled fluid flow are maintained automatically (by adjusted counterweight H4) for said measuring of material for specific gravity (by adjusted counterweight I24), discharging material according to such measurements in and from an intermediate portion between the upper and lower retained portions of the stratifying bed of material under control of and to compensate, during the feeding of raw material, disturbing influences upon the stratifying materials caused by variations in the sizing or constituents of the raw material as fed, thereby maintaining such standardized conditions of fluid agitation and material discharge and automatically adjusting them to maintain uniform plus and minus separation through a wide range of sizes and grades of raw material.

Ordinarily, adjustment of the counterweight H4 to control the air or fluid control so that no material of a specific gravity greater than the desired or selected specific gravity is present at the upper overflow discharge 2!), will be sufficient and increasing the value of the counterweight I24 will raise the splitting specific gravity while reducing the value of such counterweight will lower the splitting specific gravity to a sufficient extent within the specific gravity range of the raw material fed to the separator.

However, finer adjustments may be obtained if desired. For example, the discharging material may be brought to uniformity of grade in the various sizes by carefully adjusting the perforated rings 58 controlling the central fluid discharge, adjustment of the upper rings, in general, decreasing the minus material to substantially zero in the finer fragments of the lower discharge, adjustment of the intermediate ring bringing the intermediate sizes to uniformity and adjustment of the lower ring bringing the larger sizes to uniformity. Once adjusted to produce uniformity in the various sizes of the lower discharge, such adjustment may remain fixed.

Closer adjustments between the feed rate and air or fluid control counterweight will bring the lighter resultant of the separation to maximum output at a desired quality of perfection, and once established is final. When the quality of the separation is thus established, the splitting specific gravity may be varied as desired by increasing or decreasing the lower discharge control counterweight I24, and such automatic control adjusts the separator to meet changing conditions of grade or sizing of raw material, it automatically maintaining the adjusted splitting specific gravity and perfection of separation desired.

By employing controls for the supply of the air or other buoyant fluid and for the discharge of the heavier constituents which are adjusted by counterweights or equivalent means andwhich are governed by the torque required to rotate the upper and lower vanes in the upper and intermediate portions of the body of material undergoing separation, a standardized condition of separation is maintained automatically, and by varying the values of the counterweights or equivalent means, an desired standardized conditions may be established.

According to the present invention, an intermediate portion of the body of material being separated is retained substantially near the desired or selected splitting specific gravity, it varying somewhat from minus to plus such specific gravity, and during such variations, the fluid agitation is maintained constant by the counterweight which sustains the torque reaction from the rotating upper vanes 45.

Although discharging of heavier material downwardly from the intermediate bed of material causes such bed to become minus the selected splitting specific gravity and the resistance to fluid flow consequently decreases, abnormal or excessive fluid flow is prevented by the automatic control thereof. Also, although precipitation of heavy material into the intermediate bed brings it to plus the selected specific gravity, thereby increasing the resistance to fluid flow,

consequent impairment of proper Stratification due to too light an agitation is avoided by the automatic control of the fluid flow. By automatically maintaining a constant degree of fluid agitation during such changes in the intermediate bed of material, the measurements of specific gravity remain constant.

A similar interlocking condition is provided between the intermediate vanes 35 and the upper vanes 45. By standardized measurement of the specific gravity of the material in the intermediate bed by the counterweight I24, all material of a greater specific gravity than the desired or selected splittin specific gravity is removed downwardly from the intermediate bed, thus retaining only material of a lower specific gravity than the splitting specific gravity in the upper portion of the body of material in which the fluid control is operative to maintain such constant fluid agitation.

By varying the pressure producing the fluid flow in coordination with variations of resistance in the path of flow thereof, a uniform volume of fluid flow is maintained, and by retaining a uni form bed of material of specific gravities below that of the desired or selected specific gravity, a substantially uniform agitational buoyancy is produced in such material and a like uniform flow is produced through other lower material, and under such standardized conditions, measurements of specific gravity produced viscosity in the intermediate portion of the material are uniformly accurate.

I claim:

1. A separator comprising a separating chamher having means for feeding thereto material having constituents of different specific gravities and having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, means for agitating the material in the upper and intermediate portions of said chamber, means governed by the viscosity of the material in the upper portion of said chamber for controlling the supply of fluid thereto, and means governed by the viscosity of the material in the intermediate portion of the chamber for controlling the discharge of the heavier constituents from said chamber.

2. A separator comprising a separating chamher having means for feeding thereto material having constituents of different specific gravities and having a discharg for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, means for agitating the material in the upper and intermediate portions of said chamber, means including vanes rotatable in the upper portion of said chamber and governed by the visocity of the material therein for controlling the supply of fluid to' said chamber, and means including vanes rotatable in the intermediate portion of said chamber and governed by the viscosity of the material therein for controlling thedischarge of the heavier constituents from said chamber.

3. A separator comprising a separating "chamber having means for feeding thereto material having constituents of different specific gravities and having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents inits lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, vanes rotatable concentrically of said chamber in the upper and intermediate portions thereof, means for driving the vanes in the upper portion, of said chamber, means governed by the driving torque applied to said vanes in the upper portion of said chamber for controlling the supply of buoyant fluid thereto, means for driving the vanes in the intermediate portion of said chamber, and means governed by the driving torque applied to said vanes in the intermediate portionof said chamber for controlling the discharge of the heavier constituents from said chamber.

4. A separator comprising a separating chamber having means for feeding thereto material having constituents of diiierent specific gravities and having a discharge for lighter constiuents in its upper portion and a discharge for heavier constituents in its lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, vanes rotatable in the upper and intermediate portions of said chamber, means including a differential for driving said vanes in the upper portion of said chamber, means governed by the driving torque applied through said differential to said upper vanes for controlling the supply of buoyant fluid to said chamber, means including a difierential for driving said vanes in the intermediate portion of said chamber, and means governed by the driving torque applied through said second mentioned differential to said vanes in the intermediate portion of said chamber for controlling the discharge of the heavier constituents from said chamber.

5. A separator comprising a separating chamber having means for feeding thereto material having constituents of different specific gravities and having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, vanes rotatable in the upper and intermediat portions of said chamber, means including a differential for driving said vanes in the upper portion of said chamber, means governed by the driving torque applied through said differential to said upper vanes for controlling the supply of buoyant fluid to said chamber, means including a differential for driving said vanes in the intermediate portion of said chamber, means governed by the driving torque applied through said second mentioned difierential to said vanes in the intermediate portion of said chamber for controlling the discharge of the heavier constituents from said chamber, and means for adjustably loading said differentials to vary the response thereto of said fluid control means and the discharge means for the heavier constituents.

6. A separator comprising a separating chamber having means for feeding thereto material having constituents of different specific gravities and having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, means for supplying a buoyant fluid to said chamber at a level between said discharges for the lighter and heavier constituents, members movable in the upper portion of said chamber for circulating material therein, a valve for controlling the supply of said buoyant fluid to said chamber, driving means for said members including means governed by the power applied thereto for controlling said valve, members movable in the intermediate portion of said chamber for measuring the viscosity of the material therein, means for discharging heavier constituents of material from said chamber below the intermediate portion thereof, variable speed means for driving said discharging means, and driving means for said members in the intermediate portion of said chamber including means governed by the power applied to said members for controlling said variable speed driving means for said discharging means.

7. A separator comprising a separating chamber to contain a body of material to be separated and having discharges in its upper and lower portions for lighter and heavier constituents respectively, means for supplying a buoyant fluid to the periphery of said chamber between said discharges, means for discharging said fluid centrally from said chamber, and means for adjusting the discharge of said fluid through said central discharge at different levels thereof.

8. A separator comprising a separating chamber to contain a body of material to be separated and having discharges in its upper and lower portions for lighter and heavier constituents respectively, and having peripheral perforations for the admission of a buoyant fluid, ducts leading inwardly from said perforations and having apertures in their sides for discharging said fluid laterally into material contained in the intermediate portion of said chamber, and means for discharging said fluid centrally of said chamber and having means for regulating said discharge at different levels.

9. A separator comprising a separating chamber to contain a body of material to be separated and having discharges in its upper and lower portions for lighter and heavier constituents respectively, and having peripheral perforations for the admission of a buoyant fluid, ducts leading inwardly from said perforations and having apertures in their sides for discharging said fluid laterally into material contained in the intermediate portion of said chamber, a central discharge conduit for said 'fluid, and valves located at different levels on said conduit for regulating the discharge of said fluid at difierent individual levels.

10. The process of separating material having constituents of different specific gravities, which comprisessubjecting a body of such material to a current of fluid to render the same buoyant to a degree efficient for Stratification of such material, directing aportion of said fluid laterally through the body of material in a diagonally upward direction and with an intensity suflicient to arrange the material in sizes of progressively diminishing order from the largest size diagonally upward to the smallest size and with like sizes superposed vertically, and causing the remaining portion of said fluid to flow upwardly in said body to render the material viscous and to form a mixture of said material and fluid to effect eflicient stratification, flowing onto the top of the body a stream of raw material having the sizes thereof arranged in progressively diminishing order laterally of the stream and superposing the sizes of'material in the stream upon like sizes of material in the body, measuring the viscosity of the mixture of material and fluid in the intermediate portion of the body, and discharging the lighter and heavier constituents from the body according to a selected difference in said viscosity measurements.

11. The combination of a separator comprising a cylindrical separating chamber having upper and lower discharges for lighter and heavier constituents respectively, means for supplying a buoyant fluid thereto to effect separation of the lighter and heavier constituents and for directing a portion of said fluid toward the center of said chamber with sufficient intensity to arrange the material in sizes which diminish toward the center of said chamber with like sizes arranged concentrically, a size classifier for feeding raw material to said chamber comprising means for forming the raw material into a stream and arranging the material therein in progressive order laterally of the stream according to size, means for discharging the sized material into the upper portion of the separating chamber on a line extending radially thereof to superpose the sizes of material in the stream upon like sizes of material .in said chamber, and agitating members rotatat the periphery of said chamber at a level between said upper and lower discharges and means for discharging said fluid centrally therefrom, upper and lower vanes mounted to rotate concentrically in said chamber at upper and lower levels between said upper and lower discharges, means for rotating said upper and lower vanes, means governed by the amount of torque applied to rotate the upper vanes for controlling the supply of said buoyant fluid, and means governed by the amount of torque applied to rotate the lower vanes for controlling the discharge of heavier constituents through said lower discharge.

13. A separator comprising a cylindrical separating chamber to contain a body of material to be separated and having upper and lower discharges for lighter and heavier constituents respectively, means for introducing a buoyant fluid at the periphery of said chamber at a level between said upper and lower discharges and means for directing a portion of said fluid toward the center of the body with sufiicient intensity to arrange the material in sizes which diminish from the periphery toward the center of the body, with like sizes arranged concentrically, upper and lower vanes mounted to rotate concentrically in said chamber at upper and lower levels between,

said upper and lower discharges, means for rotating said upper and lower vanes, means governed by the amount of torque applied to rotate the upper vanes for controlling the supply of said buoyant fluid, means governed by the amount of torque applied to rotate the lower vanes for controlling the discharge of heavier constituents through said lower discharge, and means for arranging raw material in a stream with the sizes of the material diminishing in a direction laterally of the stream, and feeding the stream of sized raw material to the upper portion of said chamber on a line extending substantially radially thereof and to superpose the sizes of the material in the stream upon like sizes of material in the body.

14. The combination of a density separator having means for directing a flow of fluid therein in a lateral and diagonally upward direction to maintain the constituents of materials in the separator in sizes which progressively diminish laterally with like sizes superposed and to effect separation of the constituents according to different densities thereof, and having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, and a size separator having means for directing a flow of fluid therein in a lateral and diagonally upward direction to arrange the constituents of raw material therein in sizes which progressively diminish laterally, and means for flowing a stream of the raw sized material from the size separator onto the surface of the material in the density separator whereby the sizes of the constituents of the raw material fed from the size separator are superposed on the constituents of like sizes in the density separator.

15. The combination of a density separator comprising a separating chamber having laterally spaced means for admitting and discharging a fluid to cause a fluid flow laterally and diagonally upwardly therein sufiicient to maintain the constituents of material in said chamber in sizes which progressively diminish laterally with like sizes superposed and to effect separation of the constituents according to different densities thereof, said chamber having a discharge for lighter constituents in its upper portion and a discharge for heavier constituents in its lower portion, a size separator comprising a separating chamber having laterally spaced means for admitting and discharging a fluid to cause a fluid flow laterally and diagonally upwardly therein sufiicient to separate the constituents of raw material therein into sizes which progressively diminish laterally with like sizes superposed, discharge means including a valve for flowing a stream of the sized material from said size separator onto the surface of, the material in the upper portion of said density separator to superpose the sizes of the constituents in said stream upon like sizes of the constituents in said density separator, and means for operating said valve intermittently, said operating means being adjustable to vary the duration of the open periods of said valve for admitting said sized material to said density separator at a rate to maintain a predetermined level of material therein.

16. The process of separating material having constituents of different specific gravities, which comprises subjecting a body of such material to a current of fluid to render the same buoyant to a degree efficient for stratification of such material, directing a portion of said fluid laterally through the body in a diagonally upward direction with an intensity suflicient to arrangethe material in sizes of progressively diminishing order from the largest size diagonally upward to the smallest size and causing the remainingportion of said fluid to flow upwardly in the body to render the body of material viscous, feeding raw materialtosaid body, mesuring the viscosity of the mixture of fluid and material near the upper surface of said body, varying the intensity lighter constituents from the upper portion of said body, and discharging the heavier constituents from the lower portion of said body.

17. The process of separating material having constituents of diilerent specific gravities, which comprises subjecting a body of said material to a current of fluid to render the same buoyant to a degree efficient for stratification of such material, feeding raw material to said body, directing a portion of said fluid flow laterally through the body in a diagonally upward direction with an intensity suificient to arrange the material in sizes of progressively diminishing order from the largest size diagonally upward to the smallest size and causing the remaining portion of said fluid to flow upwardly in the body to render the body of material viscous, measuring the viscosity of the mixture of fluid and material in the upper portion of the body, controlling said fluid current in accordance with such viscosity measurements to maintain uniform visccsity in the upper portion of said body and thereby provide a similarly controlled fluid through the intermediate portion of said body, measuring the variations in viscosity of the mixture of fluid and material in the intermediate portion of said body due to heavier material stratifying therein, and discharging the lighter and heavier constitue'nts from the body according to a selected difference in said latter viscosity measurements.

18. The process of separating material having constituents of diiierent specific gravities, which comprises subjecting the lower portion of a body of such mate-rial to a current of fluid, causing the fluid to flow upwardly and controlling the force of said fluid flow to render the body of material viscous to a desired degree, for stratifying and diverting a portion of said fluid laterally through the stratifying body of material at a plurality of elevations, one above another thereby causing the remaining portion of said fluid to flow upwardly with progressively diminishing force through the stratifying body of material, while the fluid is operating upon the lower heavier strata with a force sufficient to retain the same viscous to a desired degree and is operating upon the upper lighter strata with diminishing force, controlling the amount of fluid removed at each of said elevations to thereby govern the upward diminishing force of the fluid flow to desired degrees to maintain said stratifying body viscous at all elevations to a degree efficient to effect continuous separation of the constituents of the material according to their densities within the range of their specific gravities, sinking the heavy constituents downward to the lower strata of said Viscous portions of the body, flowing said lower strata downward and discharging the heavy constituents from said downward flow, retaining the remainder of said body and flowing onto the top thereof a stream of raw material, and flowing the light residue of said raw material from the surface of said retained body.

19. The process of separating material having constituents of different specific gravities, which comprises subjecting the lower portion of a body of such material to a current of fluid to render the same buoyant to a desired degree, diverting a portion of said fluid laterally through the body of material in a diagonally upward direction and with an intensity sufficient to arrange the material in sizes of progressively diminishing order of their size range diagonally upward to the smallest size and with like sizes superposed vertically and causing the remaining portion of said fluid to flow upwardly through the upper portion of the body of material to render the same buoyant to a degree different from the buoyancy of the lower portion of said body and to form a range of viscous fluid and material mixtures in sufliciently fluid condition to effect eflicient separation of the constituents of the material according to their densities within the range of their specific gravities, measuring the viscosity of the mixture of the material and said remaining portion of fluid in the upper portion of said body and entering the fluid current to the body according to a selected difference of such viscosity measurements, flowing onto the top of the body a stream of raw material having the sizes thereof arranged in progressively diminishing order laterally of the stream and superposing the sizes of material in the stream upon like sizes of material in the body, maintaining said range of viscous conditions of the body and sinking the heavy constituents downward to the lower strata of said viscous portions, flowing said lower strata downward and discharging the heavy constituents from such downward flow, retaining the remainder of the body of material and flowing the light residue of the entered raw material from the surface of the body, and discharging the light constituents from such residual flow.

20. The process of separating materials having constituents of different specific grav'ities, which comprises introducing into a body of such material a flow of fluid and discharging such fluid from the upper central portion of the body whereby said fluid is caused to flow diagonally upward into said central portion of the body, feeding a measured portion of raw material to said body, controlling the introduction of said fluid to remove the fines from the interstices between the larger pieces of the raw material and in the separating body and to bring a portion of the material and fluid in said body at an intermediate level thereof to a fluid condition efiicient for the separation of the constituents according to a selected difference in densities and sinking of the heavier constituents and the floating of the lighter constituents therefrom, measuring' the viscosities of the mixture of fluid and material in the intermediate and upper levels of said body, and discharging the lighter and heavier constituents from the upper and lower portions of the body respectively in accordance with selected difierences' in said viscosity measurements While retaining said body and maintaining it in a condition for efiicient separation of the constituents according to the selected difference in densities.

' JOSEPH W. REED.

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