Improvements in Separators suitable for Separating Gold from Gravel and the like.
Year: 1892

page_text: Date of Application, 29th Feb., 1892
Complete Specification Left, 29th Nov., 1892-Accepted, 25th Feb., 1893
PROVISIONAL SPECIFICATION.
Improvements in Separators suitable for Separating Gold from
Gravel and the like.
I, JOSEPH ALLISON COOMBES, of 12 Carteret Street, Queen Anne's Gate, in
the City of Westminster, Mining Engineer, do hereby declare the nature of this
invention to be as follows:-
According to this invention the gravel is fed from a hopper onto a series of
jigging sieves placed above a receptacle through which a current of air is drawn in
an upward direction so that any gold in the dust, owing to its high specific gravity,
falls to the bottom of the receptacle and is there retained whilst the dust, being
lighter, is sucked up the exhaust pipe. In its passage to the fan the exhaust pipe
is bent from a vertical to a horizontal direction and an enlargement, having at its
bottom a second receptacle, is formed in it. This second receptacle retains any
very small particles of gold that may have been carried up.
The sieves, which are say three in number, fit in grooves in a box so that they
can be replaced by other sieves of different mesh. The sieves have upon their
upper surface a number of transverse ridges or bars sufficiently high to retain any
nuggets of gold but not sufficiently high to retain the gravel which rides up over
them owing to its lesser weight and passes off over their ends as tailings.
The box containing the seives has a jigging motion given to it by a rod oonnected
by a series of bell crank levers to the rod from an eccentric upon a shaft driven by
a band from a pulley on the main shaft.
The fan is actuated by hand in the following manner:-the main shaft is cranked
carrying bandles and has fixed to it a chain wheel which by a chain drives a pinion
upon the same axis as another chain wheel which by a second chain drives a pinion
on the axis of the fan.
In the vertical portion of the cylinder I have one or more serrated swivels or
disintegrators for the purpose of disintegrating any damp or pulpy material that
may be fed into the machine.
damper for the
Also I have in the interior of the machine an air throttle or
purpose of regulating the strength of the air blast that passes through the
machine.
Dated this 29th day of February 1892
CARPMAEL & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Separators suitable for Separating Gold from
Gravel and the like.
I, JOSEPH ALLISON COOMBES of 12 Carteret Street, Queen Anne's Gate in
the City of Westminster, Mining 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:-
My invention has reference to separators suitable for separating gold from gravel
and the like without the aid of water, quicksilver or chemicals, and its object is to
construct an effective and portable machine to be driven by hand or other available
power.
In the separators constructed according to my improvements there is a series of

page_text: jigging sieves on to which the gravel or material to be treated is fed from a hopper.
The sieves are placed above a receptacle through which a current of air is drawn
in an upward direction by means of a fan or exhauster so that the gold. contained
in the dust or material that passes through the sieves falls owing to its higher
specific gravity to the bottom of the receptacle and is there retained while the
dust or lighter material is sucked up the exhaust pipe. The exhaust pipe is at
first vertical, and then it is bent from the vertical to a horizontal direction, and in
the horizontal portion is an enlargement having at its bottom a second receptacle.
This second receptacle retains any lighter particles of gold or any flour gold that
may have been carried up. The jigging sieves which are two or more in number
fit in grooves in a box or frame so that they can if required be replaced by other
sieves of different mesh. The sieves have upon their upper surface a number of
transverse ridges or bars sufficiently high to retain nuggets but not sufficiently high
to retain the gravel or pieces of rock and the like, which ride up over them owing
to their lesser specific gravity and pass off over the ends as tailings; but a catch
gutter may be fitted to the lowest sieve to receive any nuggets that may pass over
the ends. In the vertical portion of the exhaust pipe are one or more serrated
swivels or disintegrators for disintegrating any damp or pulpy material that may be
fed into the machine and pass through the sieves. There is also in a suitable part
of the exhaust pipe an air throttle or damper for the purpose of regulating the
strength of the air blast that passes through the machine. The box containing
the sieves receive its jigging or to and fro motion preferably by means of a rod
connected by a series of bell-crank levers to a rod of an excentric upon a shaft
driven by a band from a pulley on the main shaft. When the machine is worked
by hand the main shaft is fitted with one or more crank handles, and for the
purpose of actuating the fan it preferably has fixed to it a chain or band wheel
which by a chain or band drives a pulley upon the same axis as another wheel,.
which by another chain or hand drives a pulley on the axis of the fan.
The acompanying drawings represent a separator or machine constructed
according to my invention. In these drawings
Figure 1 is a side elevation partly in section of the machine,
Figure 2 is an elevation of the front end,
Figure 3 is a section on the line 3-3, Figure 1, looking in the direction of the
arrow 3x;
Figure 4 is a plan;
Figure 5 is a section on the line 5-5 of Figure 1 looking in the direction of
the arrow 5* this figure also shows part of the vertical portion of the exhaust.
pipe in section, so as to allow the serrated swivel or disintegrator to be seen.
Figure 6 shows the throttle valve or damper in plan.
Figure 7 is a plan of the sieves.
a is the hopper into which the gravel or material containing the gold to be
separated is placed, and from which it passes to the uppermost sieve; bb bare
three superposed sieves; they are held in a box or frame c to which a jigging or
oscillating motion is imparted as hereinafter described. The gold or other dust or
fine particles pass through the sieves into the shoot d whilst the gravel and stones
are projected as tailings over the end of the sieves. On the upper surface of the
sieves are transverse ridges or bars e e (Figure 7) to retain any nuggets but not
sufficiently high to retain the gravel and stones, which owing to their less specific
gravity ride up over them. In case any nuggets should pass over with the tailings
they are caught by a catch gutter attached to the lowest sieve; the nuggets
being heavier than and therefore not projected so far as the gravel, fall into the
catch gutter. The gold dust and fine particles pass down the shoot d to the lower
end of an exhaust pipe y through which a strong current of air is maintained by
means of a fan h. Below the shoot and exhaust pipe is a receptacle i into
which the gold owing to its higher specific gravity falls, while the lighter particles
are drawn up the exhaust pipe, and in order to ensure and facilitate such fall holes
or perforations are made in the recptacle i through which a current of air is drawn

page_text: by the fan so as to pass in an upward direction through the receptacle i; this.
current meets the current drawn down through the shoot d by the fan, and thereby
causes a sort of eddy which favors the separation and fall of the gold. The first
portion of the exhaust pipe g is vertical and the next portion is horizontal. In the
horizontal portion is an enlargement having at its bottom a second receptacle j
which also admits a current of air from the outside by means of perforations.
This receptacle j catches and retains any very small particles of gold or any flour
gold that may have been carried up the exhaust pipe with the waste material, the
eddy produced by the meeting of the two currents of air again favoring the
separation and deposit of the gold. The second receptacle ; and the enlargement.
to contain it are not necessary where none of the gold contained in the material to
be treated is in such fine particles or of such a nature as to be liable to be drawn
the vertical part of the exhaust pipe g. In the vertical portion of the exhaust
up
pipe are one or more serrated swivels or disintegrators (only one is shown in
the drawings) which are caused to revolve by the air current so that they
disintegrate any damp or pulpy material that may have been fed into the machine
and passed through the sieves. There is also in the exhaust pipe an air throttle or
damper preferably perforated to regulate the strength of the air blast. The
jigging or oscillating motion of the box containing the sieves bb is given to it by
a rod m connected by a series of bell-crank levers and rods m¹ m² m³ m' as shown
in the drawings to a rod n from an excentric p on a shaft driven by a band from a.
pulleys on the main shaft t. The main shaft is actuated by hand by means of
crank handles uu and drives the shaft of the fan at the required speed by wheel
and belt gearing consisting of a wheel on the main shaft driving by means of a
belt a pulley on an intermediate shaft on which is a wheely that by means of
a belt drives a pulley on the fan shaft as shown. The mechanism for imparting
the requisite rotation to the fan and jigging motion to the sieves may obviously be
varied, but that which I have shown in the drawings has been specially designed
by me for the purpose and I have found it to answer exceedingly well. It need
hardly be stated that instead of driving the machine by hand power it can be
arranged to be driven by any other available power.
=
Although my improved separators have been hereinbefore described as suitable
for separating gold from gravel and the like it is obvious that they are likewise
adapted for separating other metals such for example as silver from pulverized
quartz and the like.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :
1. The combination, substantially as hereinbefore described and shown in the
accompanying drawings, of a series of superposed jigging sieves or screens which
throw off the gravel, stones and the like as tailings, retain nuggets or larger
particles of metal and give passage to the fine particles, a shoot for conducting the
fine particles to the bottom of an exhaust pipe which is at first vertical and then
horizontal, and a receptacle below the bottom of the exhaust pipe having holes or
perforations for inlet of air to meet the air drawn down the shoot, with or without
an enlargement in the horizontal part of the exhaust pipe having a second receptacle
therein to catch and retain any very small particles of metal that may have been
carried up the exhaust pipe.
2. The fitting of serrated swivels or disintegrators in the exhaust pipe as and for
the purpose set forth.
3. The combination, as hereinbefore described and shown in the drawings, with
a series of superposed jigging sieves or screens which throw off the gravel, stones
and the like as tailings and give passage to the fine particles and which have
transverse ridges or bars on their upper surface to retain nuggets or larger particles
of metal, of a catch gutter attached to the lowest sieve to receive any nuggets or
larger particles of metal that may pass over with the tailings.

page_text: 4. The combination of parts substantially as hereinbefore described and shown
in the drawings forming an improved separator suitable for separating gold or
other metals from gravel, pulverized quartz and the like.
Dated this 29th day of November 1892.
J. C. MEWBURN,
55 & 56 Chancery Lane, London, Chartered Patent Agent.