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Publication numberUS882158 A
Publication typeGrant
Publication dateMar 17, 1908
Filing dateMay 6, 1905
Priority dateMay 6, 1905
Publication numberUS 882158 A, US 882158A, US-A-882158, US882158 A, US882158A
InventorsRichard R Moffatt
Original AssigneeImp Ore Separator Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Magnetic ore-separator.
US 882158 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

PATENTED MAR. 17, 1908.




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' $51 1 @Ho e QM Zi mmw w and the space between the belts due to the accumulation of the ore as the cross belt moves the separated ore, this cross UNITED STATES PATENT OFFICE.



Specification of Letters Patent.

Patented March 17, 1908.

Application filed May 6, 1905. Serial No. 259,116.

To all whom it may concern:

Be it known that I, RICHARD R. MOFFATT, a citizen of the United States of America, and a resident of the borough of Brooklyn, city of New York, county of Kings, and State of New York, have invented certain new and useful Improvements in Magnetic Ore-Separators, of which the following is a specification.

My invention relates generally to magnetic ore separators, and has more particular reference to an apparatus for separating feebly magnetic particles from the ore.

In an application heretofore filed by me on October 6, 1904, Serial No. 227,349, there was disclosed a structure in which was employed magnets united with their free ends, each magnet having poles located in vertical alinement above and below the conveyer, and so arranged as to form a plurality of fields. These magnets were arranged with their backs extending outwardly; that is with the oles betweenthe backs of the magnets. T ere are preferably two standards supporting the machine at the ends or below the back of the magnets. Intersecting the conveyer belt at a point/between the upper lower poles are cross belts for conveying the separated material out of the machine.

In ractice, difficulty issometimes experience inconveying the attracted material out of the separatin zone because of a tendency on thepart of t e ore particles to bridge over the conveyer. One object of my invention is to produce a cross conveyerfor con veying the separated material positively .out of the machine. In order to exclude the infiuence of the poles, as much as possible from conveyer will preferably be located at a point outside the space between the two opposed poles where t ere-are few lines of force.

The general arrangement of the device also presents novel features notably in the fact that the two fields with o posed upper and lower oles are produced y Iplacing two U- shape Ina nets back to bac the poles on the same side of the conveyer being of like sign but of unlike sign to the poles on the opposite side of the conveyer. The two magnets may of course be cast in one piece, or made in several pieces in magnetic circuit. Prefer- ,than the other, and means ore.

ably the magnets are supported by an extenmg an o ening through which the conveyor passes w ile the end of the magnets or poles are suspended freely.

In the particular structure here disclosed, the upper poles are made in the formof rota table cylinders, preferably moving in a direc tion parallel with that of the conveyer, atone field in the same direction, and at the other field in an opposite direction to the movement of the conveyer. The cylinders are adapted to discharge the separated material into a suitable cross conveyer such as an endless screw or worm which positively moves the material out of the machine. This cross conveyer is preferably located outside the space between the upper and lower poles, and suitable means, as a scraper or brush, is provided for removing the material from the rotating pole to the cross conveyer. The fields are so arranged that while they are in circuit with each other, one is of greater intensity are provided for varying this relative intensity of the fields by varying the open space or distance between the poles of the field or fields. The conveyer should preferably pass through the machine at a point above the neutral zone, but this is not essential to the operation fie ds or'for forcibly projecting the particles against or towards the upper pole, or at least across the neutralzone so as to bring them under the influence of the upper polewhere the lines of force are more dense, due to the cylindrical surface of the roller pole. In this type of magnetic ore separators which employs a conveyer, it fre uently happens that the magnetic circuit is roken through accident or design, while the conveyer continues to carry ore through the separator. This re sults in great annoyance and loss of valuable One object of my invention has therefore been to control the outflow from the hopper onto the feed belt by some means controlled by the magnetic circuit of the separator, so that when the latter is broken the flow from the hopper will be stopped;

In the accompanying drawings I have illustrated my invention in separate views, in which like numerals of reference have been em lo ed to designate like parts.

n t iese drawings: Figure 1 is aside elevation of a se arator embodying my invention. Fig. 2 is a ongitudinal sectional view of the of the device, as I rovide means for agitating the ore in the i spurred cylinder 6.

. 14 are also of like sign but of opposite the poles on the other side of the conveyer.

same. Fig. 3 is an end elevation, with parts broken away.- Fig. 4 is a detail view show in one means for agitating the ore in the fie d. Fig. 5 is a detail view showing the specific means by which I control the outflow from the hopper. Fig. 6 is a cross sectional view taken on line 66 of Fig. 2 showing the magnet core yoke with its opening for the conveyer and the feet for central supports. Fig. 7 is a longitudinal sectional view with arts removed showing the lines of force in the fields, and being diagrammatical in character.

In the drawings are shown two magnets placed back to back and suitably supported b the standard 1 located at their backs and allowing their poles to'be freely suspended. Between the poles of the magnets and passing through an opening 2 formedin the magnet yoke is the conveyer 3, suitably operated bythe drums 4 and the shaft 5 carrying the ma nets are placed above the conveyer, whi e the cores 9 and 10 are placed below. The poles 11 and 12 connected to the upper cores are of like sign, while the poles 13 and sign to 15 and 16 indicate the windings of the upper and lower cores respectively and lead to the binding screws 17.

In magnetic circuit and forming partthereof are collecting cylinders 19 rotating in a arallel direction opposite to or with that of the feed conveyer and acting as the up er poles to attract the magnetic artic es from the conveyer and to carry t em with them in their rotation. As the cylinders revolve, the scraper'20 or other means,

such as brushes, suitably attached to the ole pieces of theseparator and adjustable b means ofthe screw, 21 in the slot. 22, forces the magnetic articles from the cylinder into the receptadle 23, here shown in the form of a hollow tube having an open portion 24 facing the cylinder. This receptacle is connected bythe bands 25 or other suitable means to the pole pieces, and is located outside of the space between the upper and as possible the lower poles in order to exclude it as far from the magnetic field sbetween In this receptacle I place means conveying the attracted particles removed from the magnetic fields out of the machine. This means here shown takes the form of anendless screw or worm the poles.

26 operated by any suitable method, but

preferably as shown by a gear, 27 meshing with the gear 28 carried by the shaft 29 which rotates the collecting cylinder. It

will thus be seen that as the latter rotates and-its ore isforced into the receptacle, the

endless screw will operate to positively deliver the magnetic particles out of and away from the magnetic field. A similar arrangethe pole The cores 7 and 8 of the ment is provided for each upper pole, and. since it may be desired to vary the proximity of the'poles to the conveyer so that the intensity of both fields may be increased or decreased as desired, or that the succeeding field through which the belt passes may be made of greater intensity than the preceding field, I provide means for individually adjusting and securing in their adjusted position these upper poles. I accomplish this in the present instance by forming projections or lugs 30 on the upper cores and secure to these projections the screw 31, the latter, however, bemg free to revolve on the projections.' This screw passes through a threaded opening 32 formed in a portion of iece, and will, when operated, move the atter in relation to the fixed core and also, since the core is fixed in relation to the conveyer, bring the magnet rollers into nearer or farther proximity to the conveyer as desired. When the pole piece is adjusted to the desired position, it is secured by means of the bolts 33 assingthrough the pole piece into threa ed engagement with the core. The slots 34 must be provided in the pole piece to allow the latter to beadjusted vertically. One means for agitating the ore as it asses through the fields on the conveyer be t in this instance takes the following form. Through the. lower poles Iprovide a passage 35. In this pas sage operates the plunger 36 formed at its upper portion into the head plate 37. In this passage I place a spring 38 adapted to hold the head normally in contact with the conveyer belt. The op osite end of the plunger is connected to t e lever 39 pivoted at 40.6 On the shaft which carries the spurred drum for operating the conveyer belt I mount acollar 41 provided with spurs 42 which are adapted,-,as the shaft rotates, to act intermittently against the lever to move the sanie about its pivot, thereby compressing and overcoming the influence of the spring, and thus imparting a jogging motion to the plunger, thereby agitating the ore upon the conveyer belt as it passes through the fields and projecting the ore over the neutral zone or against the upper revolving pole to which the magnetic particles are attracted and cling.

43 lndicates the hopper from which the material is fed to the conveyer belt. I have here provided automatic means controlled by the electric circuit ada ted to close the discharge opening of the 0 per whenever the magnetic circuit, by accident or design, is broken. This'means takes the following form in the present instance. At the discharge opening of the ho per and mounted in the bearings 44 beneat the same, I place the member 45 adapted to revolve, and havmg a portion 46 trough-shaped. The spring 47 mounted in the 'cup 48 carried by the protherefore provided means controlled jecting hub of this member, holds the latter normally-across the discharge end of the hopper or in What may be called its closed osition. At the o posite end of the memer I provide a rocllshaft 49 engaging with the member and adapted, when operated, to turn the latter into what may be called its open position; that is, into the position where the material is free to pass through the discharge opening of the hopper onto the conveyer belt. To limit the movement of the rockshaft, I provide the stop 50 formed in the rockshaft and the sto 51 carried by the latter and a pin 52 secure to the hopper. It will be seen that by turning the rockshaft, the action of the spring is counteracted and the member turned to its open position, where the material is free to flow from the hopper to the conveyer belt. I have found in practice'that when the magnetic circuit is broken either by accident or esign, the conveyer belt ma continue to carry ore through the fields, w 'ch is undesirable. I have by this magnetic circuit adapted to hold the member in its open position so long as the magnetic current is active, but when the current is broken or interrupted, adapted to allow the action of the retractable spring to return the memberto its closed position, thus shutting ofi the feed of ore, I accomplish this by means of the band brake 53 formed over and contacting with the cap 48 in which is seated the sprin This brake is connected by means of t e rod 54 to the armature 55 which is attracted by the electro magnets 56 in circuit with the electric system of the machine.

The operation of the hopper is as follows: Assuming the member to be in its closed position so that any outflow from the hopper is prevented, the rockshaft is operated, thereby counteracting the s ring and turning the member to any desired open position where the material is free to flow from the hopper to the conveyer belt. active, the brake armature is attracted by the electro magnet and through the rod and hand brake holds the member against the action of the spring with sufiicient force to retain it in the position to which it has been turned by means of the rockshaft. The instant the magnetic circuit, however, is

broken, the armature and brake are released,

and since there is nothing to counteract the tension of the spring, the latter instantly revolves and moves the member to its closed position, thereby shutting off the feed from the hopper.

The general operation of the machine is as follows: The ore being fed upon the conveyer belt as ittravels in the direction of the arrows, is brought within the influence of the magnetic fields, the second field being referably more intense than the first fiel d in order to attract any feebly magnetic partendency to from both sides 0 The magnetic circuitticles not attracted by the first field. The ore in the fields is thoroughly agitated on the conveyer and thrown upward either against the upper pole or across the neutral'zone so and since the poles on one side of the belt are of the same olarity, there is a minimum fbrm longitudinal escapage of lines of force and the full magnetic energy is utilized to the fullest extent for doing service in the field, the lines of f0 ce extending at right angles through the conveyer belt. After the ore has been subjected to the action of the fields, the conveyer is utilized to carry away and deposit in the proper place the tailin s or non-magnetic matter w 'ch remains.

IVhat is claimed is:

1. In a ma neticore separator, a central yoke standard having an aperture, two sets of upper and lower poles arranged on opposite sides of the central yoke standard, upper and lower core ieces extending laterally t said yoke standard and in magnetic circuit with the poles and yoke standard, a feed conveyer passing between the two sets of poles and through the aperture of the yoke standard, and cross conveyers intersecting the feed conveyer.

2. In a magnetic ore separator, an upper pole, a lower pole having a passage, a feed conveyer passing between the two poles, a plunger located in the passage of the lower pole, and means for actuating said plunger to strike the feed conveyer.

3. In a magnetic ore separator, the combi nation with upper and lower poles, of a feed conveyer passing between the said poles, means for removing the material attracted by the 'upper pole and means extending through the lower poles for agitating the feed conveyer.

4. In a magnetic ore separatorzthe combination of an upper and a lower pole, means for removing the material attracted by the upper ole, a feed conveyer passing between the po es and below the neutral zone of the field, and means for projecting the particles of ore above the neutral zone of the field of force.

5. ,In a magnetic ore separator: the combination with a feed belt and means for operating the same, of a ho per, a revoluble member adapted to close t e discharge, end of the hopper, a rockshaft, adapted to turn' said member to its open osition, a cap on the projecting hub of the 'member, a s rin mounted. therein and adapted to hol the nation with a feed belt, and means for opersaid mem er to its 0 en position, a cap on seams adapted to close the discharge end of the hopper, a s ring adapted to hold said member norma y closed, a rockshaftadapted to turn said member to its open position, a brake adapted, when operated, to hold the member in its open osition, an armature connected to the bra e and adapted, when attracted, to operate the latter.

8. In a magnetic ore separator: the combination of a feed hopper, means the passage of ore therefrom, spring for shutting ofi netic brake for holding in position against the force of spring while the magnetic circuit through separator is closed and operative.

Signed at New York city this 3d day of member normally in its closed position, a brake adapted to contact with the cap, and, when operated, to hold the member in its open position, and means controlled by the ma netic circuit adapted to operate said bra e.

6. In a magnetic ore separator: the combi ating the same, of a hopper, a revoluble member adapted to close the discharge end of the ho per, a rockshaft adapted to turn a retractable the regulating device the retractile the the projecting hub o the member, a s ring mounted therein and ada ted to hol the member normally in its dlosed position, abrake operating on said cap and adapted to hold the member in its open position, an armature connected to said brake and adapted, May, 1905. I when attracted, to operate the brake. RICHARD R. MOFFATT. 7. In a magnetic ore separator: a hopper, Witnesses:


and means adapted to control the outflow ANNA Wrssnmann.

therefrom, comprising: a revoluble member for regulating the feed, and a mag-

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4122005 *Jun 13, 1977Oct 24, 1978Mineral Processing Development & Innovation AbMagnetic separator
Cooperative ClassificationB03C1/14