MACHINES FOR GRINDING, CONCENTRATING, AND REFINING TIN AND OTHER ORES IN ORDER TO EXTRACT THE METALS TV A PURE STAMP
Year: 1870

page_text: LETTERS PATENT to Samuel Henry Stephens, of Grass Valley,
California, in the United States of America, for the Invention of
"MACHINES FOR GRINDING, CONCENTRATING, AND REFINING TIN AND OTHER
ORES IN ORDER TO EXTRACT THE METALS TV A PURE STAMP"
COMPLETE SPECIFICATION filed by the said Samuel Henry Stephens
at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 28th May 1870, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SAMUEL
HENRY STEPHENS, of Grass Valley, California, in the United States of
America, send greeting.
WHEREAS I am in possession of an Invention for "MACHINES FOR
GRINDING, CONCENTRATING, AND REFINING TIN AND OTHER ORES IN ORDER TO
EXTRACT THE METALS IN A PURE STATE," and have made solemn Decla-
ration that I verily believe myself to be the true and first Inventor
thereof.

page_text: NOW KNOW YE, that I, the said Samuel Henry Stephens, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of my said Invention, and
in what manner the same is to be performed:-
My Invention relates to machinery for extracting metals from ores,
and is more particularly applicable for tin ores.
My machines are three in number, each performing a special portion
of the work, and all three being required during the process. • They
consist, first, of a machine for grinding and finely pulverizing the rock
after it has been reduced to the proper size by stamping or otherwise;
and, secondly, of a concentrator upon which the pulp or pulverized ore
is conveyed from the grinder with a sufficient amount of water, and upon
which the valuable portions are separated from the gangue. The
third machine which I use is a refining or what is known as
& "tossing tub," into which the pulverized and concentrated ore is
placed and settled by means of hammers striking its sides in the usual
manner.
In order to explain my Invention so that others will be able to
understand its construction and operation a further description is
herewith annexed, in which reference is had to the accompanying
Drawings.
A represents a vessel or tub of suitable size having a cast-iron
bottom a. The sides of this vessel may be made of wood or other
suitable material. A vertical shaft B is firmly fixed upon a solid
bedding or framework directly beneath the tub A and passes up through a
its centre. A hub or boss C of conical or approximately conical form
surrounds this shaft on the inside of the pan and serves to keep the ore
at the rim or in the grinding track. The muller D is placed upon the
upper end of the shaft B which is suitably arranged with grooves, as
shown, to permit of its easy adjustment up and down and still carry it a
around with it in its revolutions. The muller is suspended upon the
shaft by means of a yoke E and a set screw b, which passes through, a
collar on the yoke bears upon the upper end of the shaft and serves to
adjust the muller as desired. The pulverized ore is first placed in a
hopper F which is situated in some convenient manner at any desired 3
distance from the grinder. A trough G leads from the bottom of this
hopper and conveys the ore as it is fed from the hopper to a receiving
chamber H at one side of the tub A. The feeding is accomplished by a

page_text: series of wings d arranged upon the upper end of a vertical revolving
shaft which upon being revolved causes the wings to sweep a certain
quantity of the ore from the hopper down into the trough where a stream of
water from the pipe f takes it up and carries it to the receiving chamber
H, from whence it goes beneath the grinding shoes I and is thoroughly
and finely ground. After being ground the pulp thus formed passes
into the discharging chamber H' at the side of the tub opposite the
receiying chamber through an opening shown at g. Inside of this
chamber is suspended two or more magnets h which extract any iron
which may be contained in the pulp after it is calcined previous to its
being discharged. One side of this discharge chamber is made at an
inclination, as shown, and strips of wood or other material i, i, are fitted
in slides so as to lie one above another, being separated according to the
quality of ore it is desired to discharge. The pulp in this chamber will
filter through the gate thus formed and fall into the trough J, by which
it is conveyed to the concentrator. The concentrator consists of a
circular inclined table K which may be made of strips of wood or metal.
This table rests upon friction rollers and is revolved by suitable gearing
which engages the toothed rim L of the table. The trough J which
conveys the pulp from the grinder deposits it upon the circular tables or
shelves M, M¹. These tables or shelves aro stationary and the con-
centrating table revolves below them, so that the pulp will flow upon it
from them. Triangular wooden strips or blocks m are arranged on these
two tables and serve to distribute the pulp evenly upon the concentrating
table K, a quantity of water being also supplied through the parallel
trough J' which dilutes the pulp and causes it to flow more freely. As
the pulp falls upon the table K it is carried around under two or more
stationary stirrers or brushes N which are placed at different points of
the circle. These brushes are suspended from a fixed arm o by means of
flexible straps so as to bear upon the surface of the table and serve to
evenly spread the pulp, and by keeping it agitated allow the gangue or
tailings to flow over the rim of the table and into the circular trough P
which is placed around the outside rim of the table. The ore or
valuable portion by its specific gravity settles upon the table and is
carried around until it comes to a scraper Q which is hinged to the
stationary table or shelf M³ and rests upon the surface of the revolving
table K. This scraper gathers up the metal in a ridge while a stream of
water from the pipe R washes it off into a trough S which may convey
it to a second concentrator of a similar character or other receptacle, as

page_text: desired. The pipe R communicates with a supply chamber T which is
kept filled with clear water from a trough J¹, and a cock q serves to
regulate the quantity of water which it is desired shall pass through
the pipe according to the amount necessary to wash the ore from the
table.
If the ore has now been sufficiently concentrated it can be taken
directly to my refining or tossing tub, Fig. 3. This apparatus is
intended for separating any remaining fine particles of sand from the
concentrated ore which may escape from the table along with it, and it
also stratifies or graduates the ore according to its specific gravity, so
that the process of extracting the metal by further operations is greatly
facilitated.
The tub U is made of wood or metal in the manner of constructing
ordinary tanks or barrels. The bottom V divides this tub into
two chambers, the upper one serving to receive the ore while the lower
one that is below the bottom, being of less capacity, serves to contain the
machinery for operating the hammers. A hollow upright sleeve or
hub W is secured to the bottom of the tub and rises upwards directly
through its center. A spindle or shaft X is stepped into some suitable
bearing on the floor beneath the tub and passes upward through the
hollow sleeve and has secured at its upper end the yoke Y, the two arms
of which descend into the tub upon each side of the sleeve. To these
arms are secured wings or agitators r. The lower ends of the arms are
united by a rod or bar t which is arranged to clasp the sleeve W
loosely. A horizontal shaft X¹ passes through the tub below the bottom
and carries a wheel Z, upon one or both sides of which are projections 2
which serve to actuate the lever arms of the hammers. Motion is also
communicated from this shaft to the vertical spindle or shaft X by means
of bevel or other gearing. The hammers Z' are secured to one end of a
crank lever Z" which has one of its arms entering an opening in the side
of the tank and passing into the lower chamber, as shown, so that its
extremity will bear against the side of the wheel Z. One of these
hammers are arranged upon each side of the tank by pivoting at the
angle and are operated by the projections 2 on the wheel Z, so that they
will strike the sides of the tank, and by the jarring produced aid in
settling the ore. The ore may be placed in the tank by hand or other-
wise, along with a certain quantity of water, after which the stirring
arms and hammers are set in motion and the subsidence of the ores in

page_text: their separate stratas accomplished in a short time; after this the ores
will be in a fit state for smelting or other extracting process.
The three machines when used in their order will accomplish the
separation of metallic ores from mineral, earthy, and foreign substances
in a speedy and effective manner, without any appreciable loss. The
manipulations are few, and it therefore does not require the attendance
of a practised and skilful operator.
Having thus described my Invention, what I claim and desire to
secure by Letters Patent is,―
First. The grinding tub or pan A having the receiving chamber H and
discharge chamber H' upon opposite sides of the tub and receiving its
ore from a hopper F, substantially as above described.
Second. The revolving wings d for feeding the ore from the
hopper into the trough and the water pipe f, substantially as herein
described.
Third. The discharge chamber H' with its suspended magnets / for
taking up the iron from the pulp, substantially as herein specified.
Fourth. The inclined discharge gate consisting of the strips i, i,
placed one above another and separated as described for the purpose
specified.
Fifth. Adjusting the muller D by the set screw 6 passing through a
collar on the yoke E and bearing upon the upper end of the shaft B,
substantially as described.
Sixth. The annular inclined concentrating table K and stationary
inclined shelves M, M³, with their distributing strips, substantially as
and for the purpose specified.
Seventh. The suspended brooms or stirrers N and suspended
scraper Q and water pipe R, substantially as described for the purposes
set forth.
Eighth. The tub U with its elevated bottom V and central hollow
sleeve W, for the purpose specified.
Ninth. The yoke Y secured as described and having its arms provided
with agitators for the purpose specified.

page_text: Tenth. The hammers Z' with their pivoted crank lever handles Z" and
weights operated by the projections 2 on the wheel Z, substantially as
and for the purpose above described.
In witness whereof I have haraunta eat my hand and goal this 12th