LMPROVEMENTS IN THE CONSTRUCTION OF SCREENS OR SIEVES TO BE USED IN CONNECTION WITH MINING OPERATIONS, AND FOR OTHER PURPOSES
Year: 1878

page_text: LETTERS PATENT to Alexander Dick, of Cannon Street, in the City of London,
for the Invention of "LMPROVEMENTS IN THE CONSTRUCTION OF SCREENS OR
SIEVES TO BE USED IN CONNECTION WITH MINING OPERATIONS, AND FOR
OTHER PURPOSES." A communication from abroad by Adolph Schmitt, of
Biebrich-on-the-Rhine, in the Empire of Germany.
PROVISIONAL SPECIFICATION left by the said Alexander Dick at the Office
of the Commissioners of Patents on the 30th March 1878.
ALEXANDER DICK, of Cannon Street, in the City of London.
"IMPROVEMENTS IN
THE CONSTRUCTION OF SCREENS OR SIEVES TO BE USED IN CONNECTION WITH
MINING OPERATIONS, AND FOR OTHER PURPOSES." A communication from abroad
by Adolph Schmitt, of Biebrich-on-the-Rhine, in the Empire of Germany.
This Invention relates to the construction of apparatus whereby various sub-
stances can be advantageously sifted or screened, and the larger or smaller pieces
or particles thereof separated from each other. A series of plates formed of metal
and perforated with holes of various sizes to suit the materials under treatment are
connected together by means of unperforated metallic plates.
Instead of perforated metallic plates being used sheets of woven wire having
reticulations or meshes of various sizes may be employed.
The whole series of plates is placed spirally around a central axis or spindle, on
which it revolves, the length of such axis or spindle corresponding with the width
of that part of the series of perforated plates or sheets of woven wire which is pro-
vided with the largest holes or meshes, and which is placed next to the axis or
spindle, the holes or meshes diminishing towards the portion of the perforated plates
or sheets of woven wire which forms the outer end of the spiral arrangement.
Instead of arranging the plates, which may be either bent or straight, in a spiral
manner around the axis or spindle, they may be placed around the same con-
centrically, forming rings, or hexagons, octagons, or other polygonal figures.
Rains B21

page_text: At those parts of the apparatus where the size of the holes or meshes in the per-
forated plates or woven wire changes a bent sheet, acting like a gutter, is fixed in an
inclined position across from one side to the other, on which the sifted material
will slip out through tubes fixed at the end of the said gutter. The sides of the
apparatus are closed by means of suitable plates, and openings are provided for the
discharge of the sifted material to the right and left of the apparatus.
The object and use of the unperforated plates is to keep the peices or particles of
the material under treatinent which fall from above through the upper part of the
apparatus, and also those which are sifted through the lower part thereof, separate
from each other, according to their respective sizes.
This Invention admits of various modifications in matters of detail, based upon
without departing from the main principles thereof, and which will be manifest to
persons conversant with such matters.
SPECIFICATION in pursuance of the conditions of the Lotters Patent filed
by the said Alexander Dick in the Great Seal Patent Office on the 30th
September 1878.
ALEXANDER DICK, of Cannon Street, in the City of London. "IMPROVEMENTS IN
THE CONSTRUCTION OF SCREENS OR SIEVES TO BE USED IN CONNECTION WITHI
MINING OPERATIONS, AND FOR OTHER PURPOSES." A communication from abroad
by Adolph Schmitt, of Biebrich-on-the-Rhine, in the Empire of Germany.
This Invention relates to the construction of apparatus whereby various sub-
stances can be advantageously sifted or screened, and the larger or smaller pieces
or particles thereof separated from each other. A series of plates formed of inatal,
and perforated with holes of various sizes to suit the materials under treatment, are
connected together either directly or by means of unperforated metallic plates.
Instead of perforated metallic plates being used sheets of woven wire having
reticulations or meshes of various sizes may be employed.
The whole series of plates is placed spirally and horizontally around a central
and horizontal axis or spindle, on which it revolves, the length of such axis or
spindle corresponding with the width of that part of the series of perforated plates
or shects of woven wire which is provided with the largest holes or meshes, and
which is placed next to the axis or spindle, the holes or meshes diminishing towards
the portion of the perforated plates or sheets of woven wire which forms the outer
end of the spiral arrangement.
In some cases it is desirable that the inner circle of plates, but the inner circle
next to the axis or spindle only, be conical, so as to discharge the coarser pieces of
material under treatment when the apparatus is revolving.
Instead of arranging the plates, which may be either bent or straight, in a spiral
manner around the axis or spindle, they may be placed around the same con-
centrically, forming rings, or hexagons, octagons, or other polygonal figures.
At those parts of the apparatus where the size of the holes or meshes in the
perforated plates or woven wire changes a bent sheet, acting like a gutter, is fixed in

page_text: an inclined position across from one side to the other, on which the sifted material
will slip out through tubes fixed at the end of the said gutter. The sides of the
said apparatus are closed, or partly closed, by means of suitable plates or guards,
in which openings are provided and tubes fixed for the discharge of the sifted
material to the right and left of the apparatus on the ascent and descent thereof
during revolution.
The object and use of the unperforated plates is to keep the pieces or particles of
the material under treatment which fall through the perforated plates in the
apparatus, and those which have already been sifted through those plates separate
from each other, according to their respective sizes. The sifted material falls into
separate receptacles, and in order to discharge some sizes of the material on the
descent a kind of spiral cup is used, into which the material passes through the
gutter on the ascent, and is then discharged in its next descent.
This Invention admits of various modifications in matters of detail without
departing from the main principles thereof, as will be well understood by persons
conversant with such matter; and it will be seen from the foregoing description
that this Invention consists mainly in the following particulars:-That the material
under treatment passes in a straight horizontal line over the before-mentioned
perforated plates, and is not pushed sideways as in other screening and sifting
apparatus; that it has a continuous ever-returning motion; that it discharges the
larger pieces first; and that the length of each perforated plate can be made to
correspond with the quantity of that sized material contained in the bulk of the
material to be sifted. A further peculiarity is the spiral cup for discharging on the
descont of the apparatus.
I will now proceed to refer to the annexed Drawings, from which the nature of
the said Invention will bo more clearly understood.
In Figure 1 the series of perforated metallic plates is shewn at a, o being the
centre plate; and in Figures 2, 3, and 4 the unperforated metallic plates pare
represented. The axis or spindle is shewn at b.
In Figures 4, 5, and 6 the plates arranged concentrically in rings or in polygonal
figures are represented. d is the before-mentioned bent sheet, acting like a gutter,
and the tubes fixed at the end of the gutter are shewn at 6.
In Figure 6 the plates or guards, by means of which the sides of the apparatus
are closed, or partially closed, are shewn at f.
Figure 7 is a detached view of a discharging gutter & and tube e, as fixed on the
perforated plate a.
In Figure 8 the spiral cup is shewn into which the material passes through the
gutter d.
The small numbers on the Drawings indicate the number of plates having
different sizes of apertures for the material to be passed through.
Having thus described and ascertained the nature of the said Invention, and in
what manner the same is to be performed, I would observe in conclusion that what
I consider novel and original, and therefore claim as constituting the Invention
secured by the said herein-before in part recited Letters Patent is, the combination
and arrangement of parts and mechanism in the construction of apparatus for
screening and sifting materials in mining and other operations, substantially as
herein-before described and set forth.
In witness whereof, I, the said Alexander Dick, have hereunto set my_hand
and seal, this Thirtieth day of September, in the year of our Lord One
thousand eight hundred and seventy-eight.