US20756A - Improved ore-separator - Google Patents

Description

H. BRADFORD.

Ore Jigger.

No. 20.756. Patented June 29. 1858.

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AM. PHOTO'LIIHQCO-NY. (OSBDRNE'S PROCESS) UNITED STATES PATENT OFFrcE,

HEZEKIAH BRADFORD, OF NE\V YORK, N. Y., ASSIGNOR TO HORATIQ BOGERT, ()F SAME PLACE.

IMPROVED ORE-SEPARATOR.

Specification forming part of Letters Patent No. 20,756, dated June 29, 1858.

To all whom it may concern.-

Be it known that I, I'IEZEKIAH BRADFORD, of the city, county, and State of New York, have invented certain new and useful Improvements in Machines for Separating Ores from other Substances of Different Specific Gravity, which machine is also applicable to the separation of other substances from foreign matter of different specific gravity, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, making part of this specification, in which Figure l is a front elevation of the machine without the surrounding water trough or tank; Fig. 2, a vertical section taken in the plane of the axis of the crank-shaft; Fig. 3, a

vertical section taken at the line A a of Fig. 2; Fig. 4, a horizontal section taken at the line B b of Fig. 2; Fig. 5, a vertical section of the water trough or tank.

The same letters indicate like parts in all the figures.

My said invention relates to improvements on what is known as the hand-jig, which consists of a box open at top and bottom and with a sieve or perforated diaphragm, on which lumps larger than the meshes accumulate and on which the substances to be separated are supplied, and which, when thus charged, is moved in a vessel of water with a quick up-and-down motion, from which it derives its name of the jig. This up-anddown motion in the water causes-the large lumps on the sieve-to act as so many valves, which permit the water to pass through as the box descends, the effect of which is to carry up the light substances, while the particles of ore from their superior gravity descend through and against the current of water, and finally pass through the meshes of the sieve into the Water-trough below.

This apparatus as heretofore constructed and charged was necessarily imperfect in its operation and the working of it attended with much labor, for at the end of each charge the upper portion of the charge in the box had to be taken out and the box recharged, requiring much labor and loss of time, not simply to discharge and recharge, but by reason of the necessity of continuing the operation for a great length of time to insure the entire separation for eachcharge. The separation was completed much sooner at and near the top of the charge than at and near the bottom, and to avoid waste it was necessary to continue the operation until the sepathe sieve or as the equivalent thereof with the upper edge on one or more sides so low relatively to the height of water-in the trough or tank that as the box is moved up and down by a positive and quick motion the water and particles of light matter carried up by the upward currents of water -induced through the meshes of the sieve as the box descends shall flow through the apertures in the sides of the box or over the edge or edges of the box, and thus effect the separation continuously, so that fresh matter may be supplied continuously and in due proportion.

My said invention also consists in providing the Water trough or tank with one or more partitions in combination with the sieve-box, and so fitted the one to the other that as the sieve-box works up and down the light matter which is washed over shall be deposited or carried off on one side of the said partition or partitions and separated from the substance that passes through the meshes of the sieve.

My said invention also consists in supplying the said sieve-box with the substances to be separated after such substances have been sifted, so as to be of a size less than the size of the meshes of the sieve that all the particles that are of sufficient specific gravity may pass through such meshes when this mode of supplying suchsubstances is employed, in

combination with the previous charging of the surface of the sieve with particles of matter not to be separated and of a size slightly larger than the meshes of the sieve that they may rest on the surface of the sieve as the box is carried up, and by their valve-like action prevent the substances to be separated from passing through, whereby I am enabled to render the apparatus continuous and accurate in its action, for all the particles of the substances to be separated which are of sufficient specific gravity to descend against the force of the currents of water induced by the descent of the sieve are sure to find their way through the meshes of the sieve, which are opened during the descent, while the lighter particles are sure to be carried up and discharged.

In the accompanying drawings, a represents a four-sided box open at top and bottom and provided at the ends with slides 12 b, fitted to Work in vertical ways a 0, attached to the side standards of the frame. This box is suspended by connecting rods d d to two short cranks on a crank-shaft 6 above, by means of which it receives a quick up-anddown motion. This box is provided at about the middle of its height with a diaphragm f, of wire sieve or the equivalent thereof, suitably sustained on cross-bars g to prevent it from sagging too much in the middle.

Between the sieve and the upper edge the front of the box is pierced with a series of holes h, all on the same level, and this box is then surrounded by a trough or tank 1', containing water to or nearly to the height indicated by the line jthat is to say, the water should be about on a level with the lower edge of the apertures or holes h when the box is at its greatest height.

The tank or boxt' is divided in two parts by a partition 70, to separate the matter which passes through themeshes of the sieve from what flows through the apertures h; and the front part of the box dis made double, as represented at Z, to straddle and work up and down over the partition, the said partition being cut out, as at m m, near the sides of the tank to permit the Water to flow over and keep at or near the same level on both sides; but this should be sufficiently far from the ends of the box to permit the matter washed over to subside in the water before reaching these passages. The large particles of matter not to be separated and which are larger than the meshes are piled on the surface of the sieve or screen, as at n; and the substances to be separatedsuch, for instance, as copper ore are previously crushed or ground and sifted to obtain them of a uniform or nearly uniform size, and less than the size of the meshes of the sieve that they may pass through them freely. Thus prepared such substances are supplied regularly during the operation from a suitable hopper onto an inclined board at, which delivers them into the box near the back thereof, and by the jigging or up-anddown motion a kind of pumping operation is induced, the layers of large particles first laid on the sieve acting as valves to the meshes of the sieve to close them as the box is lifted and open them asit descends, thereby inducing upward currents of water through the meshes of the sieve to carry up the lighter particles, while the heavy particles, which are to be separated therefrom, descend against the upward currents by reason of their greater specific gravity, and finally pass through the meshes of the sieve and are collected below, and as the box is lifted the meshes are mainly closed by the valve-like action of the large particles of matter, which lifts the water in the box above the level in the tank that it may flow over and carry with it the lighter particles. In this way the operation may be continued as long as desired without the necessity of stopping the operation to change the charge. As the substances to be sepa-. rated are reduced to a size less than the meshes of the sieve, no particle of the required specific weight can fail to pass through, while all the particles of less specific weight will be carried over by the upward currents and discharged; and it will be seen that by changing the specific weight of the larger particles of matter laid on the sieve that the degree of specific weight of the particles to be permitted to pass through the meshes of the sieve can be regulated to the utmost accuracy, for as the specific Weight of the larger valve-like particles is increased so the velocity of the jigging or up-and-down motion must be increased to cause the upward currents to lift them and open the meshes of the sieve, and as the force of the upward currents is increased to open the meshes of the sieve greater specific weight will be required in the particles of the substances to be separated to enable them to descend against such increased upward currents to find their way through the meshes of the sieve. In this way ores of different degrees of richness may be separated from each other as well as from the crushed gangue or other foreign substances. I prefer to have the sieve so that it will be a little higher at the back edge than the front edge to facilitate the operation of separation.

It will be obvious from the foregoing that instead of the series of holes in front of the box they may be made at the sides also, and that instead of the series of holes the edge of the box may be let down to the required height to insure the discharge of the water with the lighter substances. The up-anddown motion may be given by other and equivalent means, and so with regard to the separation of the lighter discharged substances from those that. pass through the sieve any other equivalent means may be substituted for the working of the double part of the front of the box on the partition.

It will be obvious that instead of moving the sieve-box in the water-tank this may be stationary, and the water-tank or the Water in the tank be made to move up and down, as in either case the mot e of operation will be the same.

Having thus pointed out what distinguishes my invention fromthe old and well-known hand-jig, the mode of construction which I have tried with success and the modifications which I have contemplated the better to distinguish the character of my invention from merely formal changes, what I claim as my invention, and desire to secure by Letters Patent, is

1. Making the sieve-box, which has an upand-down motion, with apertures above the sieve, or the equivalent thereof, when acting in and in combination with water in a surrounding tank or trough, substantially as and for the purpose specified.

2. In combination therewith, the partition or its equivalent in the water-tank, substantially as specified, to keep the matter which is washed over separate from the substances which pass through the meshes of the sieve, as set forth.

3. Covering the surface of the sieve with particles of matter of larger size than the meshes of the sieve that they may lie on and not enter or pass through such meshes, but act as valves to such meshes, as described, when such mode of operation is to be employed for separating substances of different specific gravity which have been prepared and assorted so as to be of less size than the meshes of the sieve that they may pass through suchmeshes freely, substantially as and for the purpose specified.

New York, June 11, 1856.

HEZEKIAH BRADFORD.

\Vitnesses:

WM. H. BISHOP, CHAS. A. WILsON.

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