US113085A - Improvement in grinding-mills for ores - Google Patents

Description

duidt tata JACOB S. NISWANDER, OF OAKLAND, CALIFORNIA.

Letters Patent No. 113,085, dated March 28, 18,71.

IMPROVEMENT IN GRlNDlNG-MILLS FOR ORE-S.

The Schedule referred to in these Letters Patent and making part of the lame.

To all whom it may concern Be it known that I, JAooB S. Nrswsnnnn, of Oakland, county of Alameda, State of California, have invented au Improved Grinding-Mill for Ores; and I do hereby declare the following description and accompanying drawing are sulcient to enable any person skilled in the artor science to which it most nearly appertains to make and use my said invention or improvements without further invention or experiment.

My invention relates to improvements in the construction and operation of quartz-grinding mills, the object being to do away with'the necessity of employi'ng iron grinding surfaces, whereby the amalgamation and separation ofthe metals are always more or less retarded by the particles of iron which are detached and mingled with the pulp during the process of grindlng. l

My invention consists in so constructing the grinding-pan or structure that ordinary stones or the quartz-rock of the mine, and selected with a view to obtain a medium lcv-el face or surface, can beemployed as a bedorunder grinding surface.

The muller is constructed so that it can be filled with loose rock, which will bear and grind upon thc lower or under surface, and between which the broken or pulver-ized rock which is fed to the mill is ground.

In order to more fully explain my invention reference is had to the accoim'ianyiug drawing forming a part of this specification, in which- A represents a horizontal iron disk, which is fixed upon a vertical shaft, 15,01- otherwise arranged so that, if desired, it can be revolved in`one or either direction.

This disk is provided with a narrow vertical rim or flange, c, around its upper periphery, thus forming it into a shallow pan.

Between thisI fla-nge cfaud the center conical disk (l I pack orplace ordinary pieces of rock of any character, taking care to give as level an upper grinding surface as possible; or, if desired, the entire surface of the pan can he covered with rock properly packed,- thus doing away with the central cone. These rocks are 'placed as closely' together as possible and the interstices filled with broken stones, which are firmly wedged in between the larger ones.

In order to keep this bed of stones in place one or more rings or bands, e, can be placed upon the flange c, so as to form a sideor rim to the pan or disk A, for the purpose of keeping the bed of stones in place..

These rings canv lie-made iu twoparts and hinged together at one' side, so as to be opened out when it is desired to remove them, and held together on the opposite side by a screw 'or equivalent device, by vwhich they can he tightly drawn around the bed of stones.

The muller F consists of a circular rim or shell, which 'may or may not be provided with a. cover, as most convenient.

This rim is divided into several compartments, m, by partitions, g, as shown. In each of these compartments I place loosely large stones, such as are readily picked up about any mine. By then giving either the rim A or muller F a rotary motion the surface of one will grind upon the surface of the other and soon wear an excellent grinding surface.

The pulp or pulverized ore is then introduced through the center of the mullcr to the grinding surrocks, as required, and by this means it is possible to 'Y keep an even grinding surface at alltimes, thus insnring a better grinding of the ore fed to the mill.

\Vhen the lower grinding surface has'become wornv 'down to the upper ring this ring is removed, and the process continued until the under grinding surface has been completely worn away, when it can berenewed, as above described. y

By this means I provide a grinding surface which will be quite eifective, the sharp edges of the rocks serving to grind the pulverized ore to the required tineness. v

The vmill can be built at a small cost, and cannot get out of repair.

.I also accomplish the ,grinding of orcs without in` termingling with the pulp finely-divided iron, which always, more or less, becomes mixed with it when iron shoes and dies are used for grinding, and which is a. great drawback to the proper amalgamation of the metals.

Having thus described my invention, \Vhat I claim, and desire to secure by Letters Patent., isl l v 1. The rings or bands e, in combination with the disk A, with its flange c, anda filling or bed composed of rock, substantially as and for the purpose set forth. 2. The muller I1', with the openings m', and divided into two or more compartments, m, which are partially filled with loose rock, substantially as and t'or the pnr- 4 Witnesses WM.- H. RUNNnLs, Gao. H. STRONG.

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