Improvements in Grinding or Pulverizing Machines.
Year: 1894

page_text: Date of Application, 27th Mar., 1894-Accepted, 12th May, 1894
CUALI LEIE SPECIFICATION.
Improvements in Grinding or Pulverizing Machines.
I, SAMUEL HENRY STEPHENS Bridge Illogan Cornwall Tin Streamer 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 refers to improvements in machinery for pulverizing tin and other
ores described in the Specification of Letters Patent granted to John Toy &
Samuel Henry Stephens bearing date the 29th day of August A.D. 1882 and
numbered 4128 also in the Specification of Letters Patent bearing date the 22nd of
October A.D. 1887 & numbered 1437187
This invention refers to the shoes or rubbers used in machinery for grinding gold,
silver tin and other partially pulverized ores to extract the metal therefrom & also
for grinding paint, cement and other hard substances and has for its object the
improved shape of the shoes or rubbers, also in the arrangement of these shoes or
rubbers in the grinding pan by bringing any preferable portion of the front part
of the one shoe or rubber to touch a corresponding portion of the back part of the
preceeding shoe or rubber so as to check the material under treatment from
passing direct from the centre to the periphery of the pan, without being caught
between the grinding surfaces. There will also be projecting pieces cast on the
front parts of the shoes or rubbers to cover over the space between the remaining
portion of the front of the one shoe or rubber and the back part of the preceeding
one, which space is allowed for the purpose of conveying the material between the
grinding surfaces and this projecting piece keeps the material from rising above
the level of the top of the shoes or rubbers. There will also be a recess formed
at the outside part of the shoe or rubber nearest the side of the pan to catch &
re-grind any material which may require further reducing. The advantages to be
derived from the shape & arrangement of the shoes or rubbers in the pan as
described are that the material is compelled to pass between the grinding surfaces
before it can escape from the pan and that after being ground it can pass out of
the pan at a level of the grinding surfaces, thereby causing no accumulation of sand
& water in the pan & thus saving that amount of power which is required to
overcome the burden & friction of such accumulation in grinding pans, discharging
at the top us at present in use.
This improvement is also applicable for use in pan grinding machines at present
in use.
In order to more fully illustrate and describe the manner in which I
invention into effect I will now proceed to further describe the same with reference
carry this
to the accompanying drawings.
Fig. 1. is a vertical cross section of an ore pulverizer showing in section the
shoes or rubbers A. A.
Fig. 2. is a plan of the shoes or rubbers showing their arrangement in the pan
with the position of the projecting pieces marked by the dotted lines.
Fig. 3. is a cross section of Fig. 2 showing the spaces B. B between a portion of
the shoes or rubbers also the projecting pieces C. C. which cover over these
spaces. D. D shows the lugs by which the shoes or rubbers are attached to the
arms of the muller.
Fig. 4. shows one detached shoe or rubber with the projecting piece, C. cast
on a portion of the front, and the dotted lines indicate the space allowed between
the shoes or rubbers under the projecting piece. M. is the recess at the outside
of the shoe or rubber.

page_text: The general operation of the machine is as follows. The material to be ground
is fed to the machine by a suitable launder O inside the ring or division E. where
there are suitable holes between the arms of the muller to allow the necessary
quantity of material mixed with water to pass into the well F. and from thence
While
carried between the grinding surfaces and discharging by the outlet G.
the material has been fed to the machine from the launder O the shaft I. is being
rotated by means of the bevil gear J. J. and thus communicating rotary motion to
the upright driver K and muller L. to which the shoes or rubbers A. A. are
attached. The material is thus thoroughly pulverized. By means of the projecting
piece cast on a portion of the front part of the shoes or rubbers & lapping over a
portion of the back part of the preceeding ones the material cannot rise above
the level of the top of the shoes or rubbers, thereby not requiring to maintain a
large quantity of water and sand at one time in the pan, thus obviating the great
defect in existing machines.
Having now described the nature of my invention and in what manner the
same is to be performed I declare that I claim as my improvement in machinery
for reducing gold, silver, tin and other partially pulverized ores to extract
the metal therefrom and also for grinding paints cements, and other hard
Bubstances is
First. The improved shape of the shoes or rubbers with projecting pieces, and
the arrangement of these shoes or rubbers in the pan substantially as described
and with special reference to Figures 2 and 3 of the accompanying drawings.
Second. The general combination of the above claim with any description of pan
machinery for pulverizing or grinding ores substantially as & for the purpose
herein described.
Dated this 22nd day of March 1894.
JOHN TOY, JR.,
Agent for the Applicant.