Improvements in or connected with Crushing or Grinding Mills, more especially intended for Grinding or Reducing Ores.con- taining Precious Metals, and for Separating Metals therefrom by Amalgamation.
Year: 1892

page_text: Date of Application, 11th Mar., 1892
Complete Specification Left, 9th Dec., 1892-Accepted. 21st Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in or connected with Crushing or Grinding Mills,
more especially intended for Grinding or Reducing Ores.con-
taining Precious Metals, and for Separating Metals therefrom
by Amalgamation.
1, RICHARD EDMUND SHILL of 49 Crystal Palace Road, East Dulwich, in
the Country of Surrey Engineer do hereby declare the nature of my invention
to be as follows:-
My invention relates to mills of the kind wherein the grinding, or reducing, is
effected by means of balls revolving upon a circular track.
The object of my invention is to so feed the ore or material to be ground or
reduced that it is more efficiently acted upon by the balls than hitherto and so
that in the case of grinding or reducing ores containing precious metal the
amalgamation of the precious metals is more thoroughly effected than hitherto.
The arrangements of the mill generally are moreover such that a better grinding
or grinding and amalgamating effect is obtained than hitherto.
According to my invention I arrange the outlet or outlets from the passage' or
passages by which the ores or material to be acted upon is passed into the mill at
a point near to the lower part of the balls and close to the race upon which they
run and so also that where amalgamation is to be performed the delivery is
immediately over a bath of mercury situated close to the portion of the mill in
which the grinding effect is obtained. The outlet for the ground ore or material
from the material is situated at a higher level than the aforesaid delivery the
object of this being to prevent the finer portions of the ore or material passing
across the mill without being properly acted upon by the balls and by the mercury,
if amalgamation is to be effected in the mill. The following is the arrangement
according to my invention which I prefer, although I do not limit myself to the
precise details:
I provide a circular race mounted upon suitable foundations or framing and
having a driving shaft passing centrally therethrough. This driving shaft carries
at its upper part a boss connected to a tubular piece through which the ore. 'or
material is fed into the machine. At the lower part this tubular piece extends
outwards in the form of a frustum of a cone of such a size that it leaves a space.
between its inner surface and a portion of similar formation forming the inner part
of the main structure which carries the race and leaving at its lower part an opening
which is situated close to and above the portion of the race against which the lower
parts of the balls bear. The outlet from the mill is situated preferably at a level
about or above that of the centre of the balls.
The balls are driven by means of arms carrying anti friction rollers, the said
arms being bolted or secured to lugs formed on the exterior of the aforesaid conc.
The weight of the balls may be supplemented by means of a tray for containing
weights the said tray bearing at its lower part on the top of the balls and being
fitted so that it can revolve round the tubular piece aforesaid and yet be capable of
rising and falling thereon.
When amalgamation is to be effected a trough for containing mercury is situated
immediately beneath the delivery opening of the aforesaid cone and in close
proximity to the portion of the race upon which the lower parts of the balls act.
When the machine is in operation the material which has been reduced to a
sufficiently divided condition is fed into the tubular piece aforesaid and passes down.
through the space enclosed by its. cone and is delivered at, or about, level. with, the
lower parts of the balls. As water or other liquid is fed in with the material to be

page_text: operated upon and thus rises in the machine to the level of the outlets which are
preferably above the centre of the balls aforesaid it follows that the delivery of
the ore or material is always well beneath the level of the liquid in the mill and
cannot take a direct course across the mill without being properly acted upon by
the balls and where the mercury trough is provided, it follows also that the precious
metals in the ore or material are very efficiently subjected to the action of the
mercury thereby rendering amalgamation more complete.
Dated this 11th day of March 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Crushing or Grinding Mills,
more especially intended for Grinding or Reducing Ores con-
taining Precious Metals, and for Separating Metals therefrom
by Amalgamation.
I EMMA MATILDA SHILL of 84 East Dulwich Road East Dulwich in the
County of Surrey Widow and legal representative of the late Richard Edmund
Shill of 49 Crystal Palace Road East Dulwich in the County of Surrey Engineer
deceased 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 mills of the kind wherein grinding or reducing is
effected by means of balls revolving upon a circular track.
The object of this invention is to so feed the ore or material to be ground or
reduced that it is more efficiently acted upon by the balls than hitherto and so that
in the case of grinding or reducing ores containing precious metal the amalgamation
of the precious metals is more thoroughly effected than hitherto and, the general
arrangement of the mill is such that the grinding or grinding and amalgamating
is or are very efficiently performed.
According to this invention I arrange the outlet or outlets from the passage or
passages, by which the ore or material to be acted upon is passed into the mill at a
point near to the lower part of the balls and close to the race upon which they run
and so also that where amalgamation is to be performed the delivery is immediately
over a bath of mercury situated close to the portion of the mill in which the
grinding effect is obtained. The outlet for the ground ore or material from the
mill is situated at a higher level than the aforesaid delivery, the object of this
being to prevent float gold or fine particles of gold or fine portions of the ore or
material which may contain gold passing across the mill without being properly
acted upon.
I will describe with reference to the accompanying drawings an arrangement
according to this invention which I prefer although I do not limit myself to the
precise details, Figure 1 is vertical section and Figure 2 is a plan with the upper
part and tray removed.
I provide a circular race A mounted upon suitable foundations or framing having
a driving shaft B passing centrally therethrough. This driving shaft B carries at
its upper part a boss C connected to a tubular piece D through which the ore or
material is fed into the machine.
This tubular piece D at its lower part D2 extends outwards in the form of a
frustum of a cone of such a size that it leaves a space d between its inner surface
and a portion of similar formation at E forming the inner part of the main structure
which carries the race and leaving at its lower part an opening which is situated
close to and above the portion of the race against which the lower parts of the
balls F bear. The outlet from the mill is situated preferably at a level about or
above that of the centre of the balls as shewn at G.

page_text: The balls F are driven by means of anti-friction rollers b carried by arms b*
bolted or secured to lugs d³ formed on the exterior of the aforesaid conical
part D
The weight of the balls F may be supplemented by means of a tray I for con-
taining weights, the said tray I bearing at its lower part on the top of the balls F
and being fitted so that it can revolve round the tubular piece D aforesaid and yet
be capable of rising and falling thereon.
When amalgamation is to be effected a trough J for containing mercury is situated
immediately beneath the delivery opening of the aforesaid conical part D' and in
close proximity to the portion of the race upon which the lower parts of the balls
act. When the machine is in operation the material which has been previously
reduced to a sufficiently divided condition is fed into the tubular piece D aforesaid
and passes down through the space d enclosed by its conical part and is delivered at,
or about, level with the lower parts of the balls F. As water or other liquid is fed
in with the material to be operated upon and thus rises in the machine to the level
of the outlets which are preferably above the centre of the balls aforesaid, it follows
that the delivery of the ore or material is always well beneath the level of the liquid
in the mill and cannot take a direct course across the mill without being properly
acted upon by the balls and, where the mercury trough J is provided, it follows also
that the precious metals in the ore or meterial are very efficiently subjected to the
action of the mercury thereby rendering amalgamation more complete. I find it
advantageous to provide wings or vanes as at d on the inside of the conical part D
to act as stirrers on the water to release any air there may be amongst the material
being passed into the apparatus.
The parts most subject to wear such as the race and the under part of the tray
which bears on the balls may be made with detachable bearing parts which can be
renewed when worn. kis the feed hopper. a lubricator. ma blade for facili-
tating the ejection of the material by the outlet G and n is a pipe by which I draw
off water and sludge from above the mercury before opening the outlet n² to draw
off the mercury containing amalgamated gold.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In mills wherein crushing or grinding is effected by balls revolving on a
circular track an outlet or outlets by which the material to be crushed or reduced
in the mill is delivered near to the lower part of the balls and near to the race on
which they revolve so that the said material cannot pass to the outlet from the mill
without being first operated upon by the balls substantially as hereinbefore
described.
2. In mills of the kind mentioned and arranged as claimed by the preceding
claiming clause the combination of a mercury bath so situated that the material
passing into the mill is fed directly over the said bath and thence to beneath the
balls substantially as hereinbefore described and illustrated.
3. In mills of the kind mentioned the combination with the race and balls revolving
thereon and operated by rolling contact with drivers as described of a tray for con-
taining weights the said tray being independent of the drivers and so mounted that
it bears on the tops of the balls and is free to have a rotatory motion imparted to
it by the said balls whilst it is also free to rise and fall substantially as herein before
explained.
4. The arrangement of parts constituting a mill for grinding or for both grinding
and amalgamating substantially as hereinbefore described and illustrated in the
accompanying drawings.