Improved Centrifugal Apparatus for Sorting or Separating Ores."
Year: 1897

page_text: COMPLETE SPECIFICATION.
"Improved Centrifugal Apparatus for Sorting or Separating Ores."
I, MAURICE DEVILLE, of No. 15 Rue du Terrage, Paris, France, 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 an improved construction of centrifugal apparatus for
sorting or separating ores, which has the advantage over existing apparatus of
the kind, of greater simplicity of construction and action, and increased yield.
The sorting or separating effect is obtained by the projection of the materials
to varying distances according to their specific gravity or density by means of
centrifugal action, and is more particularly for effecting the separation of the
more valuable constituents of ores by simple and inexpensive means.
The apparatus consists essentially of a horizontal disc receiving rapid rotary
motion, to the centre of which the materials to be sorted are fed, so that by the
centrifugal action the particles are first carried along grooves extending from the
centre to the periphery, and are then projected to a distance which is pro-
portionate to their density.
Thus in the case of ores that have previously been crushed, the lightest
pulverulent particles are projected to a less distance than the less friable gangues,
and these again are projected to a less distance than the ores proper.
The various particles thus classified will consequently accumulate in annular
heaps of perfectly distinct kinds; they are collected in annular concentric
hoppers arranged on a floor at a lower level than the centrifugal disc.
The rotary motion is effected by means of a frictional driving disc acting upon
a friction pulley on the shaft of the centrifugal disc so that by shifting the
pulley nearer to or farther from the centre of the disc the speed of the centrifugal
disc can be varied at will.
The main advantage of my improved apparatus over apparatus of a similar
kind heretofore employed, consists in that the grooves of the centrifugal disc are
inclined at an angle of preferably about 45° to the radius, in the direction of
rotation, whereby the yield is rendered proportional to the speed.
I may employ in combination with the said apparatus any hydraulic device for
causing the dust or very light particles to be precipitated more rapidly.
On the accompanying drawing is shewn by way of example the construction
of apparatus which I employ by preference for carrying my said invention into
effect.
Figure 1 shews a vertical section of the apparatus, Figure 2 a plan of the
centrifugal disc, its cover being partly cut away in order to shew the arrange-
ment of the grooves.
Figure 3 shews a side view of the lower part of the machine,, the driving pulleys
being omitted.
The apparatus consists of a disc A fixed on the upper end of a vertical shaft, B,

page_text: supported by a neck-bearing in a framing C and a pedestal bearing D at its lower
end. The shaft B receives a rapid rotary motion from a horizontal shaft E with
driving pulley F, and carrying a friction disc G in contact with which is the
friction pulley H, mounted on shaft B with a key way and feather J, K. The
friction pulley consists of a sleeve H, sliding longitudinally on but made to
revolve with the shaft, on which sleeve are fitted a number of discs of leather
or other suitable material L, pressed firmly together by means of a screw nut M
screwed on to H. The sleeve H has a neck Q with which is engaged a forked
arm the boss of which is screwed on, to a vertical screw spindle N, so that by
rotating the spindle N by means of a spanner fitted on the square end R, the arm
O and pulley H can be raised and lowered so as to be moved nearer to or farther
from the centre of the disc G, which is pressed against it by spring pressure, as
shewn.
The dise A has grooves formed on it, which are inclined preferably at an
angle of 45° to the radius, but this angle may be varied.
The tops of these grooves are enclosed by a cover a fixed to the disc A
intermediately between the grooves.
The central part of the cover is formed into a hopper b.
The crushed ores to be sorted or separated are conveyed into the hopper band
falling on to the conical projection c of the disc A, it is guided into the openings
of the grooves where the separate particles are acted upon by centrifugal force
so as to be thrown to a greater or less distance on issuing from the periphery
of the disc, the particles having the smallest density being deposited in the
innermost annular hopper d while those of the next higher density fall into the
next hopper, and so on; from the hoppers the materials are led off through
shoots to wherever required.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. Centrifugal apparatus for sorting or separating ores according to the
different densities, of the materials of which they are composed, wherein a
horizontal centrifugal disc has its upper surface formed with grooves inclined at
an angle to the radius in the direction of rotation, so as in acting in the most
effectual manner upon the material to be sorted, to afford a maximum yield for
a given rate of speed with a minimum diameter of the disc, substantially as
described.
2. Centrifugal apparatus such as is referred to in the first claim, combine.l
and operating substantially as herein described with reference to the drawing.
Dated this 25th day of October 1897
ABEL & IMRAY.
Agents for the Applicant.