Improvements in Ore Concentrators.
Year: 1891

page_text: Date of Application, 3rd Feb., 1891-Accepted, 7th Mar., 1891
COMPLETE SPECIFICATION.
[Communicated from abroad by SILAS BERTENSTRAW, of Black Hawk, County of
Gilpin and State of Colorado, United States of America, Manufacturer.]
Improvements in Ore Concentrators.
I, OLIVER IMRAY, of No. 28, Southampton Buildings, Chancery Lane, in the
County of Middlesex, Fellow of the Institute of Patent Agents, do hereby
declare the nature of this invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to ore concentrators and separators in which concentration
is effected by distributing the crushed ore upon a horizontal or an inclined table or
trough, the separation of the heavier and metal bearing particles from the ligther
portion or gangue being accomplished by means of continuous oscillations or
reciprocations with sudden jarring or bumping movements imparted mechanically
to the table or trough, the ore mixed with water being fed thereon and the con-
centrates discharged therefrom at the upper end or head, while the refuse or
gangue passes off over the tail end.
The objects of my invention are economy of construction, durability and
efficiency, and facility of adjustment as I shall describe referring to the accom-
panying drawings.
Fig. 1 is a side view, Fig. 2 a plan; Figs. 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12
shew details. Fig. 13 is a perspective of the machine.
Fig. 14 is a perspective view of the hangers with portions broken away, showing
the knife supporting edges. Fig. 15 is a perspective of the upper part of one of
the standards, showing the laterally projecting frame, knife edge support, and
part of the torsion spring and its regulating means.
1 indicates the standards at the tail end, and 2 those at the head, from which the
table or trough 3 is suspended by rods 28.
The uprights 1 and 2 are connected by braces to the longitudinally extending
bumper block 8.
The concentrating table or trough 3 has two equal longitudinal compartments 4,
e ch having sides 5 and tail end or bar 6 rising a little distance above the general
plane of the table or trough.
When the tables are of wood, or of copper, or of wood lined with copper, and
the table is oscillated, receiving a blow at each oscillation, the only movement given
the material is the throw from such blow. When, however, a table of cast iron
strikes the bumper, there is not only this throw from the bumper, but all the
particles, the units of the mass of iron of the table itself are thrown into vibration,
the mass being given a tremulousness continuing from blow to blow, and this is
communicated to the material thereon as the vibrations of the glass plate are com-
mimicated to the sand upon it, and this I have found aids materially in the
separation desired; for this reason I use for such tables cast iron which is more
sensitive to the bump or jar than forged or rolled metal, as the vibration passes
through the casting without any tendency to such buckling as weakens the force
of the jar or bump producing less effect on the separation of the mineral from
the gangue ore.
Another advantage resulting from the use of cast iron is this; sheet iron and
sheet steel buckle and get out of shape, and as the grain of rolled plates is
longitudinal, the mineral, with the liberated acid, has a tendency to follow the
grain of the metal and cut through, giving it the appearance of worm eaten wood,
and thus injuring or destroying its usefulness. The grain of cast iron, however,

page_text: being rather perpendicular to its surface, does not appear to be acted upon by the
motion of the concentrated mineral or the liberated sulphuric acid.
By the cast iron table I am also enabled to dispense with the head water
employed generally in concentrators, and I thereby save the fine rich slimes
which are kept back and lost when the head water is used.
The compartments 4 are connected to form the table 3 by bolts passing through
one side of each to a midrib 7 common to both. This rib 7 projects beyond
the head of the table to form a bumper striking the bumper block 8 to give the
desired blow or jar. If desired, means of adjustment may be added to one of
the bumpers, so as to vary the amount of swing or oscillation to be permitted to
the table. For instance, a bolt in one may be made to project a greater or a less
distance, or one bumper end may be longitudinally divided, the two parts sliding
upon each other and being adjustably secured by bolts or screws, or, upon the head
of one or both bumpers, strips, or veneers of any suitable material, as old belting,
leather, or rubber, may be secured.
In order to give the greatest possible ease and freedom of movement to the
bearings for the table and so to economize power, all the bearings are on knife
edges; and the suspension rods are adjustably secured to their bearings in order
that the inclination of the table or trough may be varied as desired.
In 20 the upper end of each of the standards 1, 2, as shewn in Fig. 7 is a recess 21
to receive a bearing plate 22 (Fig. 8) which has a hole through its middle and
hollows 23 at two sides of the hole, to receive the knife edges 25 which are pre-
ferably made in duplicate, projecting from a boss 24 (Fig. 9) so that when one of
them is worn the other can be brought into use by inversion.
Two of these are put on the ends of a piece 26 (Figs. 10 and 12) having a
central hole 27 through which passes the suspension rod 28 the end of which is
screw threaded and provided with a nut for adjusting the length of the rod. The
lower ends of the suspension rods have similar bearings as shewn in (Figs. 11
and 14) formed on brackets 20 attached to the sides of the table.
The reciprocation of the table is thus effected. At the end of the machine is
mounted a shaft. 10 driven by any suitable motor and having, about its middle,
wipers 9 which work against a piece 12 (Fig. 5) held in a box 11 fixed on the table.
For the piece 12, when worn, may be substituted a fresh piece, or a piece of different
thickness may be used to vary the stroke of the table. The tops of the standards 1
are connected by a cross girder 29 (Fig. 3) along the face of which extends a
spring rod 13 having its ends, as shewn in Fig. 15, passing freely through holes in
the ribs of the standards and secured firmly by bolts 15 in clamps 14 (Fig. 4) which
have set screws 17 by screwing or unscrewing which against the faces of the
standards the rod 13 can be more or less turned.
About the middle of the rod 13 is firmly clamped a rod 18 which extends down
into the box 11 and bears against a block or set of blocks 19 which may be varied
in thickness.
When the wipers 9 move the table back a twist is conveyed through the rod 18
to the spring bar 13, and when the wiper is clear this acts as a spring driving the
the table rapidly forwards.
Upon the standards 2 are fixed arms 31 which carry the hopper box 32 supplied
with crushed ore and water by shoots 30, and which carry also a box 33 distributing
water on the table when required to wash down gangue or light material working
up from under the hopper box. It is of advantage to divide the water box 33
longitudinally by a partition into two compartments, the one with a close bottom
supplied with the water which overflows into the other having a perforated bottom,
the discharge of the water being thus moderated.
The standards are steadied by suitable braces such as 34 and 35, and the table
is guided between blocks 37. Obviously the table might be made in one compart-
ment without the middle rib 7 in which case the box 11 would have to be fixed on a
base projecting up from the bottom of the table and a bumper would have to be
fixed to its front.

page_text: Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed, I claim :-
1. In an ore concentrator, the combination of a framing, a table carried by
suspension rods, revolving wipers moving the table back and a torsional spring rod
and arm, moving it forwards substantially as described.
2. In an ore concentrator such as is above referred to, knife edge bearings for
both the upper and the lower ends of the suspension rods, substantially as
described.
3. The construction of the table or of each of its compartments in one piece of
cast iron, substantially as and for the purposes set forth.
Dated this 3rd day of February 1891.
ABEL & IMRAY,
Agents for the Applicant.