Improvements in Apparatus for Concentrating, Grading, or Classifying Crushed Ore and other Matters.
Year: 1895

page_text: Date of Application, 25th Oct., 1895
Complete Specification Left, 27th July, 1896-Accepted, 29th Aug., 1896
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Concentrating, Grading, or
Classifying Crushed Ore and other Matters.
I, WILLIAM HENRY COWARD, of Hastings Villa, Bexley Road, Erith, in the
County of Kent, Engineer, do hereby declare the nature of this invention to be as
follows:-
:-
This invention relates to an improved apparatus for concentrating, grading, or
classifying crushed ore and other matters, and is particularly intended for use in
connection with a revolving grinding mill of the well known Niagara type.
It consists of a series of cones of successively decreasing diameter rotating about
a common horizontal axis, the smaller end of each cone entering the larger end of
The set of cones are
the succeeding cone with an intervening annular space.
enclosed within an air tight chamber or casing divided by cross partitions into
compartments in which the matters passing out at the annular apertures between
the cones are received and roughly classified according to their specific gravity, or
their grade of fineness, as the case may be.
The larger end of the first cone of the series is connected by horns to a
reversely coned ring which is applied to the outlet mouth of the drum of a
Niagara or similar revolving mill the outlet of which provided with a perforated
gauze plate so as to ensure, as far as possible, only material of one grade of fineness
entering the concentrator. The cones are so connected to each other, or to a
common support, as to revolve as one with the drum of the grinding mill, or
independently, the smallest and last cone of the series entering the inlet of the
casing of an exhaust fan between which and the grinding mill the concentrator is
interposed.
In the operation of concentrating crushed ore according to specific gravity the
lightest of the particles exhausted from the mill and carried along by the current
pass directly to the fan whilst the heavier particles which fall out of the air current
on to the inclined surfaces of the cones run out through the apertures between the
cones and are received in the different compartments of the casing, the heaviest in
the first compartment and the lightest in the last compartment of the series. The
compartments are provided with a hopper-shaped bottom and sliding doors at which
the contents may be withdrawn or a worm conveyor may be used.
DL 1
Com 1905
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
Improvements in Apparatus for Concentrating, Grading, or
Classifying Crushed Ore and other Matters.
"
I, WILLIAM HENRY COWARD, of Hastings Villa, Bexley Road, Erith, in the
County of Kent, Engineer, 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 :-
This invention relates to an improved apparatus for concentrating, grading, or

page_text: connection with a revolving grinding mill of the well known roller type in which
the crushing and grinding action is produced by a heavy roller running in a hollow
cylinder revolving on a horizontal axis.
The concentrator is illustrated in the accompanying drawings, forming part of
this specification, wherein
Figure 1 is a longitudinal sectional elevation;
Figure 2 is an end elevation
i
Figure 3 is a cross section on line 3-3 Figure 1; whilst
Figure 4 shews details of certain parts.
The same letters of reference denote like parts in all the figures.
The concentrator comprises an air tight chamber or casing A divided by cross
partitions B and enclosing a series of sheet iron cones C1, C2, C3, C4, C³, Cº,
preferably of successively decreasing diameter mounted to rotate together as one
about a horizontal axis, the smaller end of each cone entering the larger end of the
next succeeding so as to leave an annular aperture D intervening between them.
The cross partitions B of the casing conform to the circumference of the cones and
divide the casing into any number of compartments E' E3 E3 in which are received
the matters passing out at the annular apertures D between the cones, the matters
tbus collected in the different compartments being classified according to their
specific gravity or their grade of fineness, as the case may be.
The larger end of the first cone C₁, of the series is connected to a coned ring F
whose conicality is reversed in direction to the cone C¹. The smaller end of the
cone is connected to the outlet mouth of the grinding mill casing G so as to
revolve therewith, or the concentrator cones may be otherwise revolved if used in
connection with any other kind of grinding mill. The larger end of the cone F
passes through an aperture in the end of the concentrator casing A, a sufficiently
air tight fit being made by means of a flange f on the ring. The cone C¹, is
connected by horns f', to the ring F, so that an annular aperture D', is 'left
between F and C, through which any matters deposited either in the cone F or C',
will be delivered to the first compartment E. The cones C¹ C² C³ etc., are
connected together by connecting fins c to which the cones are rivetted, the fins
being set radially edgewise so as to obstruct the outlets D as little as possible.
The last cone of the series passes out through a flanged opening in the rear end of
the casing A and its smaller end is made parallel to fit and turn easily within the
inlet aperture of the casing H of an exhaust fan between which and the grinding
mill G the concentrator is interposed.
In order to enable the series of cones to be readily mounted in position within
the casing A, the latter is made in two parts united by a flanged joint coinciding
with the horizontal plane of the cone axis so that by removing the upper half of
the casing the cones may be dropped into place.
The cones C1 C2 C₁ &c. are all provided with internally projecting ledges g
formed of angle iron strips inclined obliquely to the axis in such direction (having
regard to the direction of rotation of the cones) as to enable the ledges to act as
buckets to repeatedly raise the material and shower it down across the blast with a
slightly forward tendency in the direction of the blast.
For the purpose of concentrating crushed or ground ore according to the specific
gravity of the particles, which is the operation for which the concentrator is
primarily designed, the outlet mouth of the grinding mill casing G would be
covered internally with a perforated gauge plate so as to ensure as far as possible
only material of one grade of fineness entering the concentrator. The particles of
ground ore exhausted from the grinding mill G are carried along by the current
towards the fan, the particles which fall out of the air current at different points
in their passage through the cones falling on to the inclined lower surfaces of the
cones and after being repeatedly raised and showered down again by the bucket
Jedges ultimately running out through the apertures D into the_different
compartments E' E E. The heaviest particles which fall in the cones F, C1, C³,

page_text: are received in E¹, the next heaviest which fall in cones C³, C, pass into
compartment E2, the next heaviest which fall on cones C5, C6, are received in
compartment E³ whilst the lightest of all pass on to the fan.
The bottom A', of the casing is made hopper-shaped, as shewn in Figure 3, and
is fitted with sliding doors e at which the contents of each compartment may be
periodically withdrawn; or a worm conveyor may be mounted in the bottom of
the hopper-shaped bottom by which the contents of the compartments may be
continuously discharged at a spout or spouts properly trapped against the influx of
air to the casing.
The operation is similar when grading or classifying crushed ore or other
substances according to size of the particles, except that the outlet of the grinding
mill is not covered by a perforated gauge plate.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. Apparatus for concentrating, grading, or classifying crushed or ground ore or
other matters, consisting of a series of cones constructed and operating as described
the cones being separated by intervening annular apertures but connected and
mounted to revolve together as one and enclosed within a casing divided into
compartments to receive the different grades of material escaping from the cones,
substantially as specified.
2. The combination, with a revolving grinding mill and with an exhaust fan, of
an apparatus for concentrating, grading, or classifying ore or other matters,.
consisting of a series of cones constructed and operating as described the cones
being separated by annular apertures and mounted to revolve about a horizontal
axis within a casing internally divided to receive the different grades of material
escaping from the cones substantially as specified.
Dated this 27th day of July 1896.
A. M. & WM. CLARK,
53 Chancery Lane, London, Chartered Patent Agents.
A. M. & WM. CLARK,
53 Chancery Lane, London, Chartered Patent Agents.