IMPROVEMENTS IN MILLSTONES FOR GRINDING CORN AND BOLTING FLOUR OR WHEAT
Year: 1878

page_text: "t
LETTERS PATENT to Jules Aubin, of Rue de Rivoli, No. 146, at Paris, for the
Invention of IMPROVEMENTS IN MILLSTONES FOR GRINDING CORN AND
BOLTING FLOUR OR WHEAT."
Sealed the 1st October 1878, and dated the 17th May 1878.
PROVISIONAL SPECIFICATION left by the said Jules Aubin at the Office
of the Commissioners of Patents on the 17th May 1878.
JULES AUBIN, of Rue de Rivoli, No. 146, at Paris.
STONES FOR GRINDING CORN AND BOLTING FLOUR OR WHEAT."
IMPROVEMENTS IN MILL-
A great many mills have already been constructed either with bolting or sifting
millstones, or, in the case of ordinary plain millstones, with shaking and bolting
francs for partially separating the flour from the bran whilst the grain is in the
nill itself, but they have always performed very imperfect work.
I have sought to construct a portable mill of easy removal and transport, capable
of grinding perfectly, and then to completely separate the flour and the bran, so
that the flour be entirely extracted and as pure as possible. This I have accom-
plished by the construction of the mill, mounted on a carriage or truck, forming
the object of the present Invention.
This mill is applicable to working at places where agricultural operations are
carried on, it may be used as an adjunct to threshing machines and also be
employed with advantage for armies in the field. A miller might then travel with
his mill or let it out, as the owners of threshing machines do at present.
In carrying my Invention into effect an annular space is reserved around the
lower or bed millstone, between which and the wooden crown the grist thrown out
by the centrifugal force all round the millstones falls in a shower into this annular
space, whereby it is thinned out.
The revolving millstone turns on the lower millstone by means of a cross piece
and a sleeve placed in the ordinary way at the upper part of the mill shaft or

page_text: spindle. This shaft rests at its lower part in a socket, whose height may be varied
for regulating the space separating the two millstones; it is guided in a bearing of
the central aperture or opening of the lower millstone. The cross piece carries the
basket or eye into which the corn is led through the conduit of the hopper.
The drum which covers the millstones rests on the wooden crown, arranged on
the top of the base or support. The lower inillstone is kept in position on the same
base or support by means of wedge screws and centreing screws.
Beneath the millstones the shaft is enclosed by a sleeve, which rests at its lower
part on an annular socket and at the upper part in a collar. On this sleeve is
fixed a boss of cast iron, which serves to fix the arms of a rake turning above a
fixed flooring, on which the grist falls after passing through the millstones. The
rotation of the rake conducts the grist towards the spouts of two bolters arranged
beneath.
A leather or piece of india-rubber fixed to the flooring surrounds the sleeve of
the centre shaft, and prevents the passage of the grist round the sleeve.
The rake is capable of being raised or lowered as the grist accumulates or
diminishes on the fixed flooring; for this purpose the sleeve carries a helicoidal
groove in which a gudgeon from the middle of the rake engages; this is an arrange-
ment analogous to that employed in ordinary mills. In this manner the rake
serves two purposes, it conducts the grist towards the spouts of the bolters at the
same time that it serves as a regulator by raising or lowering itself according as
the grist falls in greater or less quantity. These bolters are each formed of a case,
in which revolves an inclined drum of pentagonal section, and furnished with
bolting cloth. The grist enters the drums by one end, the flour separates from the
bran, and the bran falls by itself at the end opposite to the entrance spout.
According to the speed of the millstones and the state of the ground corn these
two bolters may both be used for flour, or one may serve to bolt the bran and the
other to refine the flour; in a word these two bolters may be used as found con-
venient and according to the nature of the work. These bolters are as large as
possible; they are about 600 millimetres in diameter and five-sided.
The flour bolter has two divisions; the bran is raised by an elevator into the second
bolter; this second bolter has also two divisions and a compartment for the product
or issues, being three compartments in all. The boxes of the bolters are of sheet
iron, as are also the conduits and spouts which serve to conduct the grist, the bran,
and the flour.
I have just described the application of my system to a mill with plain lower
millstones, but I may also apply it to my mill with lower bolting millstone; in
which case I affix on the sleeve a second boss, on which arms are fixed serving to
maintain tappets which successively strike the bolting cloths of the lower millstone.
The bolters may then be advantageously employed, one to refine the flour and
obtain flour of first quality, or superfine flour, and the other to bolt the bran
I will now describe the transmission of motion:-The motive power is trans-
initted by means of a band or strap on a pulley fixed on a horizontal shaft; the
latter carries a toothed wheel which gears into a pinion fixed to the central vertical
shaft. The first-mentioned shaft also carries another pulley in connection by a
band with a third pulley which is fixed to a second vertical shaft; on this latter is
a wheel commanding the pinion of the horizontal shaft.
My mill thus constructed, which only weighs about 3000 kilogrammes, may be
placed on a carriage or truck if desired.
The supports of the whole of the mill constitute the frame of the carriage; six
columns supporting the upper floor are fixed to it by means of bolts; these columns
are united by cross pieces, which serve to maintain the various parts of the mill,
and present flanges at top and bottom. An iron ladder is provided for mounting
on to the upper floor.
The part of the frame in front of the mill remaining unoccupied is utilized for
dressing the millstones.

page_text: A box or case placed beneath the frame will serve to contain the tools necessary
for trifling repairs and dressing the stones.
The frame is provided with one or two swing bars, so that it may be drawn by
one or two horses to the desired place.
SPECIFICATION in pursuance of the conditions of the Lettors Patent filed by.
the said Jules Aubin in the Great Seal Patent Office on the 16th November
1878.
JULES AUBIN, of Rue de Rivoli, No. 146, at Paris.
"IMPROVEMENTS IN MILL-
STONES FOR GRINDING CORN AND BOLTING FLOUR OR WHEAT."
A great many mills have already been constructed either with bolting or sifting
millstones, or, in the case of ordinary plain millstones with shaking and bolting
frames, for partially separating the flour from the bran whilst the grain is in the
mill itself, but they have always performed very imperfect work.
I have sought to devise a portable mill of easy removal and transport, capable of
perfectly grinding the grain, and also of completely separating the flour and the
bran so that the flour be entirely extracted and as pure as possible. This I have
accomplished by the construction of the mill, mounted on a carriage or truck,
forming the object of the present Invention.
This mill is applicable to working at places where agricultural operations are
carried on, it may be used as an adjunct to the threshing machine, and also be
advantageously employed for armies in the field. A miller would also be able to
travel with his portable mill or let it out on hire in the same way as threshing
machines are at present let out by their proprietors.
Figure 1 of the annexed Drawing is a vertical section of the mill mounted on
its carriage; Figure 2 is a horizontal section.
Figure 3 is an elevation of the sleeve which carries the rake.
It will be seen in Figure 1 that an annular space is reserved around the lower
or bed millstone B, and between it and the wooden casing J. The grist thrown
out all round the millstones by centrifugal force falls in a shower into this annular
space, thereby becoming thinned out.
The revolving millstone A turns on the lower millstone B by means of the cross
piece C, and a sleeve placed in the ordinary way at the upper part of the mill
shaft or spindle. This shaft O rests at its lower part in a socket E, whose height
may be varied for regulating the space separating the two millstones; it is guided
in a bearing F of the central aperture or opening of the lower millstone B. The
cross piece C carries the basket or eye G into which the corn is led through the
conduit a of the hopper H.
The lid I which covers the millstones rests on the wooden casing J, arranged on
the top of the frame or support. The lower millstone B is kept in position on the
same base or support by means of wedge screws b and centering screws c.

page_text: Beneath the millstones is a chamber or enclosed space into which the grist, which
falls through the circumferential annular space surrounding the lower millstone, is
received. In the middle of this chamber is the shaft O, which is enclosed by a
sleeve K resting at its lower part on an annular socket L and at the upper part
in a collar M. On this sleeve is fixed a boss N, of cast iron, which serves to fix
the arms P of a rake turning above a fixed flooring Q, on which the grist falls after
passing through the millstones. The rotation of the rake in the chamber conducts
the grist towards the spouts of two bolters arranged beneath.
A leather or a piece of india-rubber d fixed to the flooring Q surrounds the
sleeve K, and prevents the passage of the grist around the sleeve.
The rake is capable of rising or falling as the grist accumulates or diminishes on
the fixed flooring; for this purpose (see Figure 3) the sleeve K carries a helicoidal
groove a in which a gudgeon from the middle of the rake P engages; this is an
arrangement analogous to that employed in ordinary mills. In this manner the
rake serves two purposes, it conducts the grist towards the spouts of the bolters at
the same time that it serves as a regulator by raising or lowering itself, according
as the grist falls, in greater or less quantity. These bolters are each formed of a
case X in which revolves an inclined drum R, preferably of pentagonal section, and
furnished with bolting cloth. The grist enters the drums by one end, the flour
separates from the bran, and the bran falls by itself at the end opposite to the
entrance spout e.
According to the speed of the millstones and the state of the ground corn these
two bolters may either both be used for flour, or one may serve to bolt the bran
and the other to refine the flour; in a word, these two bolters may be used as
found convenient and according to the nature of the work. These bolters are as
large as possible, being about 600 millimeters in diameter.
The flour bolter has 2 divisions; the bran is raised by an elevator into the second
bolter; this second bolter has also 2 divisions and a compartment for the product
or issues, being three compartments in all. The boxes X of the bolters are of sheet
iron, as are also the conduits and spouts which serve to conduct the grist, the bran,
and the flour.
I have just described the application of my system to a mill with plain lower
millstone, but I may also apply it to my mill with lower bolting millstone, in
which case I affix on the sleeve K a second boss, on which arms are fixed serving to
carry the tappets which successively strike the bolting cloths of the lower millstone.
The bolters may then be advantageously employed, one to refine the flour and
obtain, first quality or superfine flour, and the other to bolt the bran.
I will now describe the transmission of motion:-The motive power is trans-
mitted by means of a band or strap on the pulley U fixed on the shaft Z, the latter
carries a toothed wheel V, which gears into the pinion VI fixed to the vertical 4
shaft O. This vertical shaft also carries a pulley U₁, connected by a band with the
pulley U fixed to the vertical shaft 01; on this latter is the toothed wheel Y
gearing into the wheel Y' on the shaft Z. The shafts of the bolters are put in
motion by means of the bevil gear Y", Y, driven through the shaft O from the
shaft Z.
My mill thus constructed, and which only weighs about 3000 kilogrammes, is
placed as a whole or in parts on a carriage or truck on wheels.
The carriage frame constitutes the support of the whole of the mill; columns
supporting the upper floor are fixed to it by means of bolts; these columns are
united by cross pieces, which serve to maintain the various parts of the mill and
present ribs at top and bottom. An iron ladder is provided for mounting on to
the upper floor.
A part of the frame in front of the mill may be utilized for dressing the
millstones.
The driving gear may be placed above the frame, as on the Drawing, or beneath.
A box or case, placed beneath the frame, will serve to contain the tools necessary
for trifling repairs and dressing the stones.

page_text: The carriage is provided with one or two swing bars, so that it may be drawn
by one or two horses to the place of operation.
And having now described the nature of my said Invention, and in what manner
the same is to be performed, I declare that I claim as destinctive features of my
Invention,-
First. The arrangement of bolters, occupying all the disposable space beneath
the millstones, for directly bolting the grist fallen in a thin shower around the said
stones, as herein-before described, and substantially as shown in the annexed
Drawings.
Secondly. The employment of plain millstones or bolting millstones with a
circumferential annular empty space reserved around the lower millstone in lieu
of the conduits or tubes usually employed, as herein-before described, and substan-
tially as shown in the annexed Drawings for the purposes set forth.
Thirdly. The utilization of the two bolters placed directly beneath the millstones,
both for bolting the grist, or one for bolting the bran and the other the flour, as
hercin-before described.
Fourthly. The arrangement beneath the millstones, as described and shown, of
an enclosed chamber or space into which the grist falls.
Fifthly. The application of an automatic rake with ascending and descending
movement working in the before-mentioned closed chamber, and forming a kind of
regulator for distributing the grist to the bolters.
Sixthly. The making of my direct-bolting mill, either wholly or in parts portable
by mounting it on a carriage or truck, which permits it to be moved from one place
to another for grinding purposes, at the scene of agricultural operations, for the
service of armies in the field, and similar purposes.
Seventhly. The arrangement of the whole of my combined mill, in the manner
described.
In witness whereof, I, the said Jules Aubin, have hereunto set my hand
and seal, this Eighth day of October, One thousand eight hundred and
seventy-eight.
JULES AUBIN. (L.S.)