AN IMPROVED APPARATUS FOR SIFTING AND PURIFYING SEMOLINA AND GRITS
Year: 1876

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "AN IMPROVED
APPARATUS FOR SIFTING AND PURIFYING SEMOLINA AND GRITS."
munication from abroad by Augustin Maurel, of Marseilles, France.
A com-
Sealed the 22nd June 1877, and dated the 28th December 1876.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 28th December 1876.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
"AN IMPROVED APPARATUS FOR SIFTING AND PURIFYING SEMOLINA
AND GRITS." A communication from abroad by Augustin Maurel, of Marseilles,
France.
This Invention relates to the manufacture of semolina and grits, and more
especially to the complete separation of these products from the flour and fine bran
which are mixed therewith (after hulling and crushing hard and glutinous grain)
by a mechanical sifting combined with the action of a current of air from a fan.
The semolina, on leaving the millstones, consists of a mixture of flour, coarse and
fine bran, grains of semolina of different sizes, some of which are perfectly pure, and
the rest, notwithstanding the grinding, with pellicle still adhering thereto, of germs
of wheat, small stones, and dust. This mixture is first passed through the bolter, to
eliminate the flour and coarse bran, after which it is treated in an apparatus termed
a purifying sieve, whereby the semolina is separated from the rest of the flour still
adhering to the grains, and the fine bran which has not been removed in bolting
and the semolina is classified according to the size of its grains.
Figure 1 of the accompanying Drawings shows a longitudinal clevation, and
Figuro 2 a longitudinal vertical section of the apparatus; Figures 3 and 4 are
end views, and Figure 5 a transverse section of the same taken on line Y, Z,
Figure 2.
The same letters of reference indicate the same parts in all the Figures.
The annaratus is constructed of a main frame I, I, of wood supporting casing G,

page_text: in which the compressed air is received from a fan at one end. This casing is
divided internally into a number of double hoppers P, P, for receiving the sifted
semolina classified or sorted, according to size, which is discharged through the
spouts Q. E is an upper fraine in which is mounted the sieve, which is composed
of silk or skin, having perforations of different sizes for sifting and classifying the
grains. A, hopper receiving the matters to be sifted after the grinding and bolting
operations, whence they are delivered upon a roller B, by which they are distributed
on a table C serving to regulate the delivery to the sieve.
The several working parts of the machine are all driven by a band on pulleys O
on a shaft J which may be, however, driven by hand, and at the opposite end of
said shaft is another pulley O, from which notion is imparted to a small pulley on
the end of the fan shaft L; pulley O' also serves, through the toothed gearing N, to
drive the distributing roller B. K, two connecting rods attached to the eccentric
shaft J, by which the sieve D is vibrated, the return motion being assisted by the
spring rods F, whereby a jerking notion is produced which facilitates the sifting;
M, M, bearings of shafts J and L.
I have before mentioned that the casing G, which receives the air blast from the
fan, contains a number of double hoppers P, P, coupled together transversely, each
double hopper being separated from the next by an intervening space near the base
of the inverted pyramid, which they form. These spaces may be either open or
closed by wings or valves on shafts operated by handles H, H, outside the casing,
by which means the passage of air beneath the sieve during the progress of sifting
is regulated. When the fan is in operation the air supplied circulates throughout
the casing around the hoppers to a certain height, whence it escapes between them
past the valves, and is projected upwards against and beneath the sieves, for the
purpose of ventilating and purifying the semolina, as is clearly shown in the
Drawings.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the 26th
June 1877.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent. "AN IMPROVED APPARATUS FOR SIFTING AND PURIFYING SEMOLINA
AND GRITS." A communication from abroad by Augustin Maurel, of Marseilles,
France.
This Invention relates to the methodical manufacture of semolina and grits, and
more especially to the complete separation of these products from the flour and fine
bran (after hulling and crushing hard and glutinous grain) by sifting by mechanical
means, and the action of a current of air judiciously applied.
The semolina, on leaving the millstones, consists of a mixture of flour, coarse and
fine bran, grains of semolina of different grades, some perfectly pure, and the rest,
notwithstanding the grinding, having pellicles of bran still adhering to them, germs
of wheat, small stones and dust. This mixture is first passed through the bolter, to
eliminate the flour and coarse bran, after which it is treated in the apparatus of this
Invention termed a purifying sifter, whereby the semolina is separated from the
remaining flour that still adheres to it, and from the fine bran not removed by the
bolter; the semolina is also classified according to grade or size of grains. Many
machines have been applied for the same purpose, but none have yielded satisfac-
tory results, either to the manufacturer or consumer.
The use of a current of air has long been recognised as necessary for obtaining
pure products, even in hand sifting with a riddle or sieve, and it has been applied
in many ways, and products of very good quality have been obtained by hand

page_text: eifting, but not sufficient to supply the makers of alimentary pastes, who require
large quantities of semolina rapidly manufactured at low cost and of unexceptionable
quality.
The purifying sifter of this Invention exactly fulfils the above requirements, and
before describing it in detail I would have it understood that it not only forms a
nechanical substitute for hand work, but the improved construction and the
judicious distribution of air beneath the sieves of this Invention may be applied to
perfect existing machines.
A perfect mechanical sifter should, 1st, yield the largest possible quantity of
purified semolina per diem, so that a limited number of these machines may suffice
for a flour mill; 2nd, effectually separate and classify the seinolina, according to
grade 3rd, perform this operation with the least number of siftings, so as to avoid
repeatedly passing the semolina over the same sieve; 4th, utilise as completely as
possible the unpurified semolina; 5th, combine with it such a judicious distribution
of the air current that it may be directed to or cut off from any part of the sievo,
or increased in forco at any particular point required; 6th, be of simple mechanical
construction, easily kept in order, receive the raw material and deliver the manu-
factured products in a regular and self-acting manner without skilled labor.
theso advantages are combined in the improved apparatus for sifting and purifying
semolina and grits herein described, and one example of which is shown in tho
accompanying Drawings.
All
Figure 1 shows a longitudinal elevation, and Figure 2 a longitudinal vertical
section of the apparatus; Figures 3 and 4 are end views, and Figure 5 a transverse
section of the same taken on line Y, Z, Figure 2.
The same letters of reference indicate the same parts in all the Figures.
The apparatus is constructed of a main frame I, I, of wood supporting a fan at
one end and a trunk or casing G, in which the air is received. This casing is
divided internally into a number of double hoppers P, P, for receiving the sifted
semolina graded or sorted, according to size, which is discharged through tho
spouts Q. E is a frame supporting the frame of the sieve, which is made of silk or
skin, having perforations of different grades for sifting and classifying the grains.
A, hopper receiving the materials to be sifted as they come from the grinding and
bolting operations, whence they are distributed by a roller B and sloping lodge C
to the sieve.
The working parts of the machine are driven by a band running on fast and
Motion is imparted
loose pulleys on a shaft J, which may also be driven by hand.
to the fan shaft L by a band on pulleys O, 02. Pulley O¹ also drives the distributing
roller B through the toothed gearing N. K, two connecting rods from the eccentric
shaft J, whereby the sieve D is vibrated, the return movement being assisted by
the spring rods F, so as to produce a jerking motion, which facilitates the sifting;
M, M, bearings of shafts J and L.
I have before mentioned that the casing G, which receives the air blast from the
fan contains a number of double hoppers P, P, coupled together transversely, each
double hopper being separated from the following one by a narrow interval. Theso
spaces may be either open or closed by wings or valves on shafts operated by
handles H, H, outside the casing, by which means the passage of air beneath the
sieve during the process of sifting may be regulated as required. When the fan is
in operation the air supplied circulates throughout the casing around the hoppers to
a certain height, whence it escapes between them past the valves, and is projected
upwards against and distributed beneath the sieves, for the purpose of ventilating
and purifying the grains of semolina, as is clearly shown in the Drawings. The
number of hoppers and air-regulating valves in the casing may be increased
at will.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is, the improved system of apparatus for

page_text: sifting and purifying semolina and grits, operating substantially as shown and
described.
In witness whereof, I, the said Alexander Melville Clark, have. hereunto set
my hand and seal, this Twenty-sixth day of June, in the year of our Lord
One thousand eight hundred and seventy-seven.
A. M. CLARK. (L.S.)