Improvements in or relating to Apparatus for Sifting or Classifying Flour and other Small or Pulverulent Material.
Year: 1899

page_text: Date of Application, 15th Apr., 1899-Accepted, 10th June, 1899
Improvements in or relating to Apparatus for Sifting or Classifying
Flour and other Small or Pulverulent Material.
A Communication from AGNENIO AGNENI, Baker, of 196, Via Cola di Rienzo,
Rome, Italy.
I, ALFRED JULIUS BOULT, of 111, Hatton Garden, in the County of London,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to apparatus for use in screening, sifting and classifying
flour and other small or pulverulent material, and is illustrated by way of example
in the accompanying drawing,
Figure 1 representing a longitudinal section of the apparatus part of the outer
cylinder 6 being broken away so as to show the interior."
Figure 2 is an end view of the apparatus.
Figure 3 is a cross section on an enlarged scale.
Figure 4 is a plan view part of the framing being shown opened or removed for
the purpose of showing the brushes u.
Figure 5 is a detail view of the blades which cover the inner cylinder a.
Figure 6 is a modification of the apparatus for working on a large scale.
Figure is a view of one of the brush devices.
The apparatus comprises a case a shaped preferably as illustrated in the draw-
ing, and divided in the interior by diaphragms c according to the various qualities
or finenesses into which the material to be treated is to be classified. The said
diaphragms form compartments, marked in Figure 1, by the numbers 1, 2, 3,
4 and 5. The case is supported by six or other number of feet 6. At the ends
of the case is supported a central shaft d in bearings ff1 carried on blocks ee¹,
the shaft d being rotated by means of a crank handle y or by power. On the
shaft are supported the frames of iron or wood of the cylinders a and b, which
are covered with sieving material, and a pulley & which transmits its movement
to the pulley o of the feeding hopper h, which is arranged on the upper part of the
case, by means of supports y. The hopper, lined with sheet metal is provided at
the bottom with a feeding worm i, actuated by the pulley o, to feed the material
from the hopper into the inner cylinder a. Above the feed worm i is a metal
bar or frame provided with small cross bars provided with points. The frame
which can slide laterally on two ledges or supports is held by springs at the rear
part, so that when it is drawn forward by a cord, the frame has an alternate
reciprocating movement; in consequence of this movement the small points or
blades fixed to the cross bars cause the material to be treated to descend on to the
feeding worm, in case it should get packed by its own weight. The cylinders a
and 6 are covered with silk netting or by metallic cloth, as in the case of the
ordinary bolting or sifting mills. The size of mesh is gradually reduced in the
two cylinders, and begins with the finest that is to say with the smallest meshes
at the mouth or entry end and along the whole length of the compartment 1; a

page_text: The
medium mesh is employed in division 2; and a larger one in division 3. It must,
however, be remembered that the netting covering the interior cylinder a ought
always to be in proportion, and gradually less close, or less compact than the
netting covering the outer cylinder b. Owing to such an arrangement, the
ligneous portion of the wheat &c. (bran or husks) or large parts of other material,
will fall from the end of the cylinder a into the division 5, completely separated
from the material, and from the outer cylinder will fall into division 4.
powdered crushed parts such as waste, also perfectly separated from the flour;
whilst into the other divisions 1, 2 and 3, will fall the flour or other material of
the first, second, and third qualities respectively. The mouth of the cylinder b
is perfectly closed up to the contact with the cylinder a while the cylinder a is
only partly closed in a circular manner. The cylinder a is provided with a
series of blades 1, which for each series are of the same length as the divisions 1, 2,
and 3, of the apparatus. These blades are fastened on to wood or otherwise, and
are prolonged at their extremities into projections %, engaging in eyes q, in which
the said end can freely turn during the movement of the apparatus so that the
blades will overlap and cover the upper part of the cylinder a, while those in the
lower part occupy a vertical position allowing the material to fall freely out of
the cylinder a as clearly represented in Figure 3. The said blades may also be
made to turn in this manner by passing through them a wire fixed at its two
extremities. The blades are provided at their lower ends with cloth or fibrous
edges which serve to diminish noise, and which at the same time keep the
interior of the cylinder clean, by continually brushing against the inner walls of
the cylinder b, and facilitate the passing of the flour. To keep the outer surface of
the cylinder clean, a series of soft brushes u made of fine hair or of other
material, may be articulated and suspended by a wire (see Figure 7) secured to
eyelets fixed to the partitions c. In order that these brushes should not be upset
or overturned by the rotary movement of the cylinder, they are kept in position by
slight springs v which also serve to give them the necessary amount of elasticity.
At the further end of the case a' the blocks e which support the shaft are adapted
to slide vertically in two grooves m, by means of two screws t, by which greater
or less inclination can be given to the cylinders, as required. The case a is pro-
vided at the lower part, corresponding with the sub-divisions 1, 2, 3, 4, and 5
with receptacles or hoppers for the reception of the different qualities or sizes of
the product passed through the apparatus. The said receptacles are closed at their
lower ends by doors or slides, so as to be able to regulate at will the discharge
of flour or material.
The front end of the apparatus is closed by means of a door e¹ (Figure 2) pro-
vided with a handle and a small window through which the interior may be
inspected, without the necessity of constantly opening the door. The door is held
in place by turn springs. The other end is closed although also provided with
a small window pl.
The casing is provided with two or more hinged parts providing openings, on
one side by a board X divided in two parts, and on the other side by two boards X,
one extending the whole length of the apparatus and the other divided into two
parts.
If it is desired to substitute power for hand work, it is sufficient to remove the
crank handle y and to apply a belt to the pulley k and if desired to replace the
hopper by conducting or feeding tubes. For apparatus on a large scale these
devices offer the advantage of reducing the number of apparatus necessary for the
refining of the flour or other material treated. In such case each cylinder should
have only one netting over its whole surface of uniform mesh, always keeping in
mind that that of the outer cylinder should be closer, i.e. of smaller mesh than
that of the interior cylinder.
In place of the two cylinders a and b (by means of which work is performed
equal to that of two ordinary apparatus) other cylinders may be added provided
with covering blades or plates, thus forming an apparatus equal, as regards work,

page_text: to that of the three or four ordinary apparatus.
In working on a large scale and
if there are two single cylinders a and b, the receptacles 1, 2, and 3 are removed
and replaced by a single one h² (Figure 6) at the bottom of which is arranged a
conveying worm 21, actuated by a pulley and delivering the flour or material
into the feeding tubes. Where a larger number of cylinders is employed there
will be as many receptacles as there are qualities of flour or material to be
obtained.
The blades pivotted on the cylinders act to prevent the material which has
passed through a cylinder from returning and to brush the inner surface of the
adjacent cylinder and also to provide a certain amount of ventilation and move-
ment which facilitates the passage of the material in the different cylinders.
Having now particularly described and ascertained the nature of the said
invention as communicated to me by my foreign correspondent and in what
manner the same is to be performed I declare that what I claim is ;--
1. Apparatus for use in sifting or classifying flour and other small or pulverulent
material comprising two or more rotatory sifting cylinders arranged one within
the other, and having a common shaft for revolving them in the same direction,
the second cylinder refining or classifying the product of the first, and the third
that of the second, and so on, the interior cylinder or cylinders being provided
with a series of hinged blades provided preferably with brushes or the like at
their outer ends, each series of said blades preventing the material which has
passed through one cylinder from returning to it, and also brushing the interior
surface of the next cylinder and producing in the interior of the cylinders a certain
amount of ventilation and movement which facilitates the passage of the material
in the different cylinders substantially as described.
2. Apparatus for use in sifting or classifying flour and other small or pulveru-
lent material comprising two or more concentric sifting cylinders ab. pro-
vided with longitudinal blades, such as 1, a casing divided into a number of par-
titions with corresponding discharge receptacles, such as 1, 2, 3, 4 and 5, and
means for rotating the cylinders and introducing the material to be treated into
the inner cylinder, substantially as described.
3. The complete apparatus for use in sifting or classifying flour and other small
or pulverulent material, substantially as described or illustrated in the accom-
panying drawings.
Dated this 15th day of April 1899.