IMPROVEMENTS IN CENTRIFUGAL BOLTING MACHINES
Year: 1877

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J. Brandt
and G. W. von Nawrocki, Civil Engineers and Patent Agents, of No, 2, Koch
Strasse, Berlin, in the German Empire, for the Invention of "IMPROVEMENTS
IN CENTRIFUGAL BOLTING MACHINES." A communication by Ferdinand Feistel,
of the Firm of F. Feistel & Co., of Berlin, in the German Empire.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 15th February
1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. von
Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch Strasse; Berlin; in the
German Empire. "IMPROVEMENTS IN CENTRIFUGAL BOLTING MACHINES." A com-
munication by Ferdinand Feistel, of the Firm of F: Feistel & Co., of Berlin, in the
German Empire.
"
The present Invention has reference to an improved construction of centrifugal
bolting machines for separating the fine from the coarse flour or meal and bran
whereby such machines are rendered more effective in their centrifugal action, while
at the same time the flour or meal to be sifted is brought under the action of the
rotating blades in a much more open and equably distributed manner than here-
tofore, so as to enable the blades to act much more effectually upon each particle of
flour, meal, or bran presented to them. For this purpose the cylindrical sieve or
"silk" is made of larger diameter than heretofore, as are also the rotating blades,
whereby a greatly increased centrifugal action is obtained, while a central space can
be formed within the inner edges of the blades of sufficient size for containing a
central sifting and distributing cylinder, made either of perforated sheet metal or
of wire gauze, within which is a second set of revolving blades. Thus, instead of
the coarse meal or flour to be sifted being introduced as heretofore in a solid stream
directly on to the first-named revolving blades at one end of the machine, whereby
only a very imperfect action of the blades upon the meal is obtained, the meal is in
the improved arrangement first introduced into the central sieve through which it
is caused by the inner revolving blades to pass in an equably distributed manner
and in a very open condition upon the outer revolving blades, to be acted upon.
them in the usual manner. The said inner sieve may be made to take the place of

page_text: the preparatory sifter, which is usually employed for separating the coarsest bran
from the meal before it is introduced into the bolting machine. For this purpose
the perforations or meshes of the sieve are made sufficiently small at the feeding
end of the machine to prevent the passage through them of such particles, while
at the other end the perforations are made sufficiently large for the greater portion
of the particles to fall through into a spout below, while the largest particles are
caused to pass from the inner surface of the sieve into another spout at the end
thereof. The inner sieve and its blades is for the above purpose made to extend
some distance beyond the outer blades and sieve.
The inner blades are slightly oblique to the central axis, so as to cause the meal
to travel along the sieve at the same time that they exert a certain centrifugal
action thereon. The inner blades are carried by arms on a central revolving shaft,
which at the inlet end of the machine has a disc fixed thereon extending beyond
the outer surface of the inner sieve, and serving as means for the attachment of
the one end of outer blades, these being made of sufficient strength to carry them-
selves without further support, and their other ends connected together at the
required distance apart by a metal ring. The said disc on the shaft to which the
outer blades are attached has, projecting outwards beyond its boss, a tubular
elongation into which fits the fixed inlet spout for the meal, within which is a
screw blade fixed on the shaft for feeding the meal forward. From this spout the
meal passes into the inner sieve through a number of radial passages formed in the
boss of the disc, the meal being thus made to enter the sieve in a more or less
dispersed condition. The inner sieve is connected to the framing of the machine
only at the delivery end, the inlet end having an inner metal flange surrounding
the boss of the before-mentioned disc, and on a projecting rim of this boss is fixed
a ring of bristles kept in contact with the said flange, so as effectually to prevent
the escape of meal through the space between the boss and the flange.
The outer cylindrical sieve is formed with openings of two or more different
degrees of fineness in the course of its length, so as to deliver flour or meal of
different degrees of fineness into corresponding spouts at the bottom of the sur-
rounding casing. A spout is also provided at the end surface of the outer sieve
for conducting away the coarse particles that are retained in the interior surface
thereof. The outer sieve is formed of three separate segmental parts bolted together,
and the outer casing is also formed of three separate parts, two of which are
removeable so as to gain access to the interior of the machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Gerard Wenzeslaus von Nawrocki in the Great Seal Patent Office
on the 11th August 1877.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. von
Nawrocki, Civil Engineers and Patent Agents, of No. 2, Koch Strasse, Berlin, in the
German Empire. "IMPROVEMENTS IN CENTRIFUGAL BOLTING MACHINES," A com-
munication by Ferdinand Feistel, of the Firm of F. Feistel & Co., of Berlin, in the
German Empire.
The present Invention has reference to an improved construction of centrifugal
bolting machines for separating the fine from the coarse flour or meal and bran,
whereby such machines are rendered more effective in their centrifugal action, while
at the same time the flour or meal to be sifted is brought under the action of the
rotating blades in a much more open and equably distributed manner than here-
tofore, so as to enable the blades to act more effectually upon each particle of flour,
meal, or bran presented to them. For this purpose the cylindrical sieve or "silk"
is made of larger diameter than heretofore, as are also the rotating blades, whereby
a greatly increased centrifugal action is obtained, while a central space can be
+

page_text: formed within the inner edges of the blades of sufficient size for containing &
central sifting and distributing cylinder made either of perforated sheet metal or of
wire gauze, within which is a second set of revolving blades. Thus, instead of the
coarse meal or flour to be sifted being introduced as heretofore in a solid stream
directly on to the first-named revolving blades at one end of the machine, whereby
only a very imperfect action of the blades upon the meal is obtained, the meal is in
the improved arrangement first introduced into the central sieve through which it
is caused by the inner revolving blades to pass in an equably distributed manner
and in a very open condition upon the outer revolving blades, to be acted upon
them in the usual manner. The said inner sieve may be made to take the place of
the preparatory sifter, which is usually employed for separating the coarsest bran
from the meal before it is introduced into the bolting machine. For this purpose
the perforations or meshes of the sieve are made sufficiently small at the feeding
end of the machine to prevent the passage through them of such particles, while at
the other end the perforations are made sufficiently large for the greater portion of
the particles to fall through into a spout below while the largest particles are caused
to pass from the inner surface of the sieve into another spout at the end thereof.
The inner sieve and its blades is for the above purpose made to extend some distance
beyond the outer blades and sieve.
The inner blades are slightly oblique to the central axis, so as to cause the meal
to travel along the sieve at the same time that they exert a certain centrifugal
action thereon. The inner blades are carried by arms on a central revolving shaft,
which at the inlet end of the machine has a disc fixed thereon, extending beyond
the outer surface of the inner sieve, and serving as means for the attachment of the
one end of the outer blades, these being made of sufficient strength to carry them-
selves without further support, and their outer ends connected together at the
required distance apart by a metal ring. The said disc on the shaft to which the
outer blades are attached has, projecting outwards beyond its boss, a tubular
elongation into which fits the fixed inlet spout for the meal, within which is a
screw blade fixed on the shaft for feeding the meal forward. From this spout the
meal passes into the inner' sieve through a number of radial passages formed in the
boss of the disc, the meal being thus made to enter the sieve in a more or less
dispersed condition. The inner sieve is connected to the framing of the machine
only at the delivery end, the inlet end having an inner metal flange surrounding
the boss of the before-mentioned disc, and on a projecting rim of this boss is fixed
a ring of bristles kept in contact with the said flange, so as effectually to prevent the
escape of meal through the space between the boss and the flange.
The outer cylindrical sieve is formed with openings of two or more different
degrees of fineness into corresponding spouts at the bottom of the surrounding
casing. A spout is also provided at the end surface of the outer sieve for con-
ducting away the coarser particles that are retained in the interior surface thereof.
The outer sieve is formed of three separate segmental parts bolted together, and the
outer casing is also formed of three separate parts, two of which are removeable so
as to gain access to the interior of the machine.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 of the Drawings shows a front end view of the before-described improved
bolting machine, Fig. 2 shews a back end view.
Fig. 3 shews a cross section; Fig. 4 shews a longitudinal section; and Fig. 5,
a plan.
C is the cylindrical bolting sieve or "silk," within which are the rotating blades f
secured at one end to the disc A on the shaft b, while their other ends are all
connected to the metal ring r. In the central space within the blades f is fixed the
cylindrical distributing sieve B, extending at the outlet end some distance beyond
the sieve C, and containing the rotating blades e fixed to the shaft 6 by the arms D.
The sieve C is surrounded by a casing k, t, provided with shoots m, m, for carrying
off the meal, which is in the first instance introduced into the central sieve B

page_text: .
through the hopper a, passage c, radial passages d in the revolving disc A, by the
action of which it is spread evenly and in a loose condition round the sieve as it
enters, where it' is caught up by the revolving blades e which by their oblique
position cause it to travel along the sieve B, and 'to pass through the same in an
evenly distributed condition into the sieve C, where it is again subjected to the
action of the blades f. The portion of the sieve B that extends beyond C is formed
with larger holes, so that the coarser particles of meal that could not pass into the
sieve C can escape through the shoot h, while the coarsest particles still remaining
in the sieve B are led away through the spout i.
The sieve C is also made with coarser perforations at the front end than at the
back, so that fine meal is delivered into the shoot m, coarser meal into n, while
the coarsest particles pass from the interior of the sieve through the spout o. The
sieve B has at its inlet end an annular flange v, and on the projecting rim g of the
disc A is fixed a ring of bristles u which is kept in contact with the flange v, and
is thus made to close the inlet end of the sieve against the escape of meal.
The casing is formed with removeable sides having handles p, and secured by
catches, as shewn at Fig. 5.
Having thus described the nature of the said Invention, and in what manner the
same is to be performed, I claim,―
First. Arranging within the cylindrical sieve of bolting machines one or more
concentric distributing sieves with revolving arms or blades, substantially as herein
described.
Second. In centrifugal bolting machines the combination of the concentric sieves B
and C with revolving blades e, f, and disc A, with radial passages d, arranged and
operating substantially as herein described with reference to the accompanying
Drawings.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this Twenty-sixth day of July, in the year
of our Lord One thousand eight hundred and seventy-seven.
GERARD WENZESLAUS V. NAWROCKI.
(L.S.)