US823492A - Magnetic separator. - Google Patents

Description

$15,823,492. :PATENTED JUNE 12,1906.

L. A. DUN A MAGNETIC SEPARATOR;

APPL IOATION FILED mm. s, 1902.

' 1 4 z snnm's-snnntr 2.

s I netic teeth i the improvement. liesin .vergences at its-surface diagonally with respect toa line. joining the magnetic centers.

' LEWIS A. DUNHAM, OE'KANSAS CITY, MISSOURLhSSIGNOR, BY'MESNE' ASSIGNMENTS, TO INTERNATIONAL seranaron COMPANY, or CHI- 1'0 ll whom at may concern:

.iQ'oAeo, ILLINOIS, A noRroRAnoN on NEW JERSEY,

rsaeusrio eseana'ros it known thatI, LEWIS A. DUNHAM, a citizen of'the United States, residing at Kansas City, in. the. county of J ackson and S tete ofiMissouri, haveinventcd aeertain new and usefiiljlmprovement in Magnetic Separate rs, (GaseNo. 1,) ofwhich the ollowing is a full, clear,v concise, and. exact description, reference being had to the accompanying draw' ings, formmg a part of this specification.

as This-invention relates to a magnetic sepa- ,path diver entirom the less 'ratorof the type in which the material to be separated is passed between a movable carrier, such asr'a rotating cylinder, and an opposing imagneteplole, the carrier having mager means for producing convergences of the lines of force toward its surface, saidc'arrierand pole-piecebeing so dis posed that the more permeable particles of.

material inthe mixture are carried into a ermeable particles, whic are allowed to fall away.

The object of this invention is to produce a more efiectiveseparation, especially in treating materials of very low permeability, and the combination with such a separator of means for maintaining the maximum magnetic flux suhstantially undimiin's'hed through an extended range of movement of the materials undergoing separation below and beyond the point where the unattracted material is first free to fallaway fromthe attracted material. 'As

'an example of suchmeans; there may. be'provided in combination with a hollow separatv ,ir1g-cylind'er and a magnet-pole facing the outer side thereof a second. magnet-pole inside the cylinder and offset with respect to eabiia lS-held by the undir'ninish said outer pole, so as to distort downwardly themagnetic flux from said outer pole and concentrate the same upon the cylinder along a-segment which liesbelow and beyond the segment immediately facing said outer pole. In such construction the rotation ot the cylinderflwill therefore move the flux con of the two pole-pieces. The result is that after the --un'attra'cted material is free to fall the attracted material even of verylow per- 1n magnetic flux in a path divergent from said falling unattracted material until it has passed Specification of Letters "Patent,- 1 Application filed December 8,1902. smart. 134,288.

Patented June 12, 1906.

beyond a point where a divider may main tain the separation. In other words, thev v magnetic field'is extended in the direction of movementof the magnetic teeth carrying the attracted material, so as to greatly increase the distance. through which any particular tooth may be moved" without materially re ducing the 'fiux through. such tooth, thus holding the attracted material until it is widely'separated from the material not attracted.

In the. accompanying drawings, Figure 1 is a side elevationof the separator. 'Fi 2 is a sectional'plan view thereof, taken on line 2 2 of Fig. 1. Fig. 3 is a sectional elevation taken on line 3 3 of Fi 2, and Fig; 4 is an enlarged sectional view diagrammaticallyillustrating the distrihuti on of the efiective magnetic field.

The same referencecharacters designate; the same parts in all the figures.

The separator consists in its elements of a" cylinder mounted to rotate between oppos- 7 5 in magnet-poles. In the form shown the' cy inder is hollow, and a magnet 4 is mounted inside said cylinder, extending diametrically across the same and having its pole-faces 5 6 facing the inner peri hery thereof. The energizing-winding 9 is s own as wound upon the inner magnet 4 between said poleefaces 5- 6. An' iron yokepiece l. surrounds the separating-cvlinder and is provided with poles 28 24, facing the opposite sides thereof. 8 5

As will be noted, the inner' magnet iis angularly disposed with reference to the 'outer pole-pieces 23 24, so that the inner pole-face 5 is offset with respect, to the outer polepiece 23 and has 'the effect of distorting 9o downwardly the magnetic flux of said outer pole, as shown most clearly in Fig. i. The

magnctscore 4 issupported by an angularlyadjustable shaft 7, a set-screw 8' being pro vided tov hold the shaft andcore in adjust- 5 ment. e r

The separating-cylinder is made up of a framework or cage comprising transverse rods 13 13, extend1m betweentheend plates 10 1'0, and segmentdlplates' or laminae, hav 10o ingteeth' or projections 14 14 on their outer edges, said plates being assembled between the transverse rods 13 13 to build 11) the body of the cylinder. It will be noticed that the construction of the cylinder is such as to re 5 readily permit the passage of magnetic lines radially through the body thereof, although the longitudinal gaps between. the rows of toothed plates interpose a considerable reluctance to the passage of a magnetic flux circumferentially through the cylinder. The teeth upon the segmental plates are adapted to cause local eonvergences of the magnetic flux toward the surface of the. cylinder built up thereby.

The cylinder is provided with by which it may be rotated, the rotation being indicated by the arrow 1.8 in Fig. 3. The material to be separated is received by a hopper 15 and is fed through the spout 16 thereof onto the surface of the rotating cylinder, which carries the same past the magnetole 23. A shield 17 is provided to prevent t iie materials from being thrown off the carrier centri'lugally. Collectors 20 and 22 are )rovided underneath the cylinder to receive t e separated products.

The magnet having been energized by current from the dynamo 19 passing through the coil 9, there is set 11' a magnetic flux r adially through the cylinr or between the inner magnet at and the outer pole- pieces 23 and 24, respectively. The flux is diagrammatically ndicated by dotted lines in Fig. 4. The projecting iron teeth cause convergences of the lines of force, as shown. The more permeable particles of material passing over the cylinder are attracted to the teeth is and held thereby until they are carried past the dividing-point between he collectors 20 and 22, said attracted particles being finally discharged into the collector 22 after having been carried )ast the region of intense maga pulley 253, direction of netic field. he non-magnetic material, be-

ing unattracted by the cylinder, falls over the side thereof into the collector 20.

In machines of the t pe under consideration in order efiectua ly to separate mag netic materials of low permeab lity from a mixture containing materials still lower permeability it is necessary that a very intense magnetic flux be provided and that the attractive force thereof shall be exerted at an eilicient angle to the force of gravity so that the unattracted material may. fall away from the attracted material. in machines of this character heretofore constructed there has been great diiliculty in maintaining a suliiciently intense magnetic iiuX throughout such-an extended range of movement of the attracted material after the nonmagnetic 'material is free to fall that a divider date can be placed between the two classes oi inaterial. In order to e'liect a separation, the non-attracted material must be free to fall away from the attracted material, and it has been difficult to establish a magnetic flux of suflicient intensity acting at the required angle to the force of gravity and through a suiliciently-extended range ofmovement of the materials Without placing a magnet-polc of an opposin in such position as to interfere with the free fall of the unattrncted material.

In accordance with the present invention the inner magnet 4 is adjusted. to an inclined position, as shown in Figs. 3 and 4, so that the inner pole 5 will face anarc on the inner periphery of the cylinder considerably oilset below the arclaced by the outer pole-piece The magnetic flux is thereby distorted downwardly, so as to be concentrated along a considerable arc oi the cylinder below the horizontal diameter thereof, While the outer polo-piece 23 does not extend into the path of material falling vertically downward over the side of the cylinder. On account of the downward distortion of the 11 rain body of magnetic flux the magnetic tecili carrying the attracted material move diagonally with respect to the'mean direction of the flux, and so the magnetic saturation of the teeth is in aintaincd to the rerniired degree tl'n'ough an extended range of movement below and. be yond the place of separation-that is, the place where the unattracted material is first free to fall. away from the attracted material. By this means the attracted material, even of very low permeability, hold by the carrier until it is carried a considerable distance from the place of separation, this result being accomplished without interfering with the free fall of the material not attracted.

The density of the magnetic flux through the cylinder rapidly decreases in the direction of rotation of the cylinder beyond the lower edge of the pole-piece 5, so that the material attracted to the cylinder is released shortly after passing beyond the arc of its path iaced by said pole-piece 5 and fal s into collector .22.

The invention claimed is l. A magnetic separator comprising a movable separatingcarrier having means for causing convergenccs of magnetic flux toward its surface, magnet-pole facing said carrier, and means for passing material to be separated downwardly through the air-gap between said carrier and said pole, in combination with means for downwardly distorting the magnetic flux between the pole and said carrier.

A magnetic separator comprising a cylinder rotatable upon a substantially horizontal axis, and a magnet-pole facing the side of said cylinder, in combination with means for maintaining a magnetic flux of maximum densit, between said pole and said cylinder throughout an extended are on the surface of said cylinder below and beyond the lower edge of said magnet-pole.

3. in a magnetic separator, the combination with a magnetic cylinder mounted to retate upon a substantially horizontal axis, said cylinder having means for causing convergences of me. :tic flu toward its surface, .xguet-pole facing the side of trated magnetic flux from the outerpole is rated throu h the gap tion with a ho said cylinder and lying outside a vertical lane tangent to sald cylinder, and "means or distoitlng the flux from said pole down-- wardly along the under surface of said carandsaid pee-piece, and a magnetole facing the inner surface of saidcylin er along an arc ofiset obliquely below the are faced by; said outer pole-piece; whereby the concen' distorted ownwardly toward the under surface of the cylinder, While a clear space is left below for the free fall of the unattracted material.

' 5. In a magnetic separatorgthe' cornbina J tion with a hollow-separat' of magne t pole-pieces outside an inside ofsaid. cylinder respectively, said pole-pieces' heing offsetiwith reference to each other.

tion with magnet pole-pieces, of- -means for causing a convergence n the magnetic flux between said pole-pieces, and): means for moving said convergence obliquely with res ect to a line joining the magneticcenters of tion begins.

a "'35 In wi-tness whereof I hereunto. subscribe my name" this 6th dayofJDecember,

' 6. In a magnetic separatonthe' combma-j I t e 'ole-pieces,-said pole-pieces being formed to 'e outside a vertical plane extending downwardly from the place at whichseparav '1

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