Improvements in Apparatus used in Purifying and Sorting Semolina, Middlings, and other such Substances.
Year: 1893

page_text: Date of Application, 22nd Feb., 1893
Complete Specification Left, 21st Nov., 1893-Accepted, 13th Jan., 1894
Improvements in Apparatus used in Purifying and Sorting Semolina,
Middlings, and other such Substances.
I, WILLIAM WALTER WILLIS, of 14 Wherstead Road, Ipswich, in the County
of Suffolk, Miller, do hereby declare the nature of this invention to be as
follows:-
:-
This invention relates to improvements in machines principally used in flour mills
for sorting classifying and purifying semolina middlings and other such substances by
dividing or separating the said semolina middlings or other substances into various
grades according to their specific gravity or size by means of currents of air.
In this invention the air currents are in turn purified while in transit round the
machine.
The purified air returning to the head of machine free from dust to continue the
work of sorting classifying and purifying the material.
The various products are automatically collected and conveyed out of the
machine through suitable openings provided with valves to prevent any air being
drawn into the machine. The said machine being. altogether self contained
requiring no air to be let into it and blowing none out while it is so constructed that.
no baffling takes place while the separations are being made.
The apparatus consists of a closed casing near one side of the top of which is a
hopper for introducing the material to be treated into the machine and near the
opposite side a fan for causing a continuous circulation of air around the interior
of the casing.
The particles of semolina or middlings as they pass from the hopper fall into the
current of air and are more or less carried along with it according to their specific
gravity-ranged side by side below the hopper are a series of division hoppers set
close together side by side.
The heavier material falling into the first hopper is delivered by it on to a sieve
which inclines slightly downwards and has a short reciprocating to and fro motion
given to it. The material falling into the other hoppers is delivered by them on
to trays which are carried one above the other above the top of the sieve the
lower part of the division hoppers the trays and sieve being all carried by the sieve
frame. The boards forming the upper part of the hoppers can be made to incline
more less in any desired direction to bring their upper ends into the positions
required.
A current or currents of air are drawn through the sieve by the fan which
causes any unsound semolina or middlings to float on top of the sieve and to
tail over the end along with germy or other material too large to grade through.
the sieve where they are joined by the material passing over the lowermost tray.
They both drop into a channel up which an upward current of air is directed..
The channel delivers the material to a conveyer by which they are conveyed out.
from the machine to rolls for further treatment.
The material falling on to the next tray and which consists principally of small
branny particles having a little good material adhering to them are passed out of
the machine through a suitable trough at the bottom of the tray and may be passed..
on to the course tailings roll.
The material falling on to the uppermost tray is pure offal and may be conveyed.
away by a trough at the lower end of the tray. The pure semolina passing through
the sieve is collected by a hopper below it and led away by a conveyor to be

page_text: passed to the rolls. Any light particles lifted up by air currents from the sieve
and by the upward currents of air at its end are deposited on to the uppermost.
tray with the other offal.
The dust laden air drawn into the fan is discharged downwards into a channel
at the end of the casing. In this channel the downward current of air comes
against a series of boards one below the other at a distance apart from
another in opposite sides of the channel and inclined downwards towards one
another.
one
The dust carried along with the air striking against these boards is arrested
and drops to a hopper at the bottom whilst the purified air escapes between the
boards and passes along the bottom of the casing which is also made to form a dust
catcher.
At the opposite end air is allowed to pass through a valve and rise upwards to
pass below the bottom of the hopper and so back to the fan. Air is also allowed
to pass through other valves to the hopper below the sieve and over the lowermost
tray. A valve is also provided for controlling the freedom with which air can
pass to the fan.
Any number of divisions may be made in the machine according to the material
to be treated-preferably from one for fine middlings to five for the coarsest
semolina. In some cases also the machine may be constructed with fixed division
hoppers and no sieve.
Dated this 21st day of February 1893.
COMPLETE
SPECIFICATION.
Improvements in Apparatus used in Purifying and Sorting Semolina,
Middlings, and other such Substances.
I WILLIAM WALTER WILLIS, of 14 Wherstead Road, Ipswich, in the County
of Suffolk, Miller, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
This invention relates to improvements in machines principally used in flour mills
for sorting classifying and purifying semolina middlings and other such substances
by dividing or separating the said semolina middlings or other substances into
various grades according to their specific gravity or size by means of currents
of air.
In this invention the air currents are in turn purified while in transit round
the machine the purified air returning to the head of machine free from dust to
continue the work of sorting classifying and purifying the material.
The various products are automatically collected and conveyed out of the
machine through suitable openings provided with valves to prevent any air being
drawn into the machine. The said machine being altogether self contained
requiring no air to be let into it and blowing none out while it is so constructed
that no baffling takes place while the separations are being made.
The apparatus consists of a closed casing near one side of the top of which is a
hopper for introducing the material to be treated into the machine and near the
opposite side a fan for causing a continuous circulation of air around the interior
of the casing.
The particles of semolina or middlings as they pass from the hopper fall into the
current of air and are more or less carried along with it according to their specific
gravity.
Ranged side by side below the hopper are a series of division hoppers set close
together side by side. The heavier material falling into the first hopper is delivered

page_text: by it on to a sieve which inclines slightly downwards and has a short reciprocating
to and fro motion given to it. The material falling into the other hoppers is
delivered by them on to trays which are carried one above the other above the
top of the sieve the lower part of the division hoppers the trays and sieve being all
carried by the sieve frame. The boards forming the upper part of the hoppers.
cau be made to incline more or less in any desired direction to bring their upper
ends into the positions required.
A current or currents of air are drawn through the sieve by the fan which causes
any unsound semolina or middlings to float on top of the sieve and to tail over the
end along with germy or other material too large to grade through the sieve.
where they are joined by the material passing over the lowermost tray. They
both drop into a channel up which an upward current of air is directed. The
channel delivers the material to a conveyer by which they are conveyed out from
the machine to rolls for further treatment.
The material falling on to the next tray and which consists principally of small
branny particles having a little good material adhering to them are passed out of
the machine through a suitable trough at the bottom of the tray and may be passed
on to the coarse tailings roll.
The material falling on to the uppermost tray is pure offal and may be conveyed
away by a trough at the lower end of the tray.
The pure semolina passing through the sieve is collected by a hopper below it.
and led away by a conveyer to be passed to the rolls. Any light particies lifted
up by air currents from the sieve are by the upward currents of air deposited on
to the uppermost tray with the other offal.
The dust laden air drawn into the fan is discharged downwards into a channel at
the end of the casing. In this channel the downward current of air. comes against
a series of inclined boards one below the other at a distance apart from one
another.
The dust carried along with the air striking against these boards is arrested and
drops to a hopper at the bottom whilst the purified air escapes between the
boards and passes along the bottom of the casing which is also made to form a dust
catcher.
At the opposite end air is allowed to rise upwards to pass below the bottom of the
hopper and so back to the fan. Air is also allowed to pass below the sieve. A
valve is also provided for controlling the freedom with which air can pass to
the fan.
.
Any number of divisions may be made in the machine according to the material
to be treated. Preferably from one for fine middlings to five for the coarsest
semolina. In some cases also the machine may be constructed with fixed division
hoppers and no sieve.'
The drawings annexed show machines constructed in the manner I prefer for
carrying out my invention.
Figure 1 is a vertical section and Figures 2 and 3 are cross sections of a machine
in which sieves are used.
Figure 4 is a vertical section of a modification of the machine in which the sieves
are omitted and Figure 5 a cross section.
In Figures 1, 2 and 3, A' is a rectangular outer casing-A is a hopper near the
left hand side of the upper part of this casing and B a fan near the opposite right hand.
side. C is a sieve frame suspended below the level of the exit from the hopper
by suitable steel hangers or springs. and vibrated to and fro by an eccentric c.
Care pieces of flexible fabric or material going all round the sieve frame to:
obstruct the passage of air and compel it to rise up through the sieves. D. are the
sieves carried by the sieve frame C they are made of various degrees of fineness
the finest at the head and each section being a little coarser than the one above it.
The sieves can be cleaned by a brush D' moved to and fro continuously below it by a
double or endless screw Dwhich is rotated continuously.. C' C'C' are -hopper

page_text: spaces into which material coming from the hopper A drops. R R¹ are. adjustablei
boards at the mouths of the hoppers.
Air enters the fan casing through central openings on its two opposite sides and
is delivered from the casing into the descending channel I. At the bottom of which
is the dust catcher or hopper K. The air passes out from the lower part of this
channel between inclined baffle boards J J³. J J into expansion chamber L..
The dust checked by the baffle boards drops into the dust catcher or hopper K which
forms as it were a vacuum chamber into which the dust readily collects. The dust
which settles from the stream of air passing along the expansion chamber L
collects at the bottom of this chamber and is. swept off from it by brushes
attached to a continuously revolving endless chain M into a small hopper from
which it can be discharged into the dust catcher K. The dust can be discharged
from time to time from the dust catcher K by opening the valve at its bottom.
The air passing from chamber L rises into chambers O at the sides of the hopper H
and into the channel Q (see Figure 1) from which it passes below the exit from
the hopper A and along the upper part of the casing being deflected by the
deflector Ax and through valve R to the fan inlet openings. From the chambers O
some air also rises up through sieves D and through a series of valves N all
provided with deflectors and situated between baffle boards N* which insure the
deposit of all the light particles which may have been drawn from the sieve. The.
light particles so deposited drop into the chain conveyer S.
The material to be treated is fed into hopper A and as it drops from the hopper
it meets the current of air from the fan and is thereby separated according to its
specific gravity into the various division hoppers C: CC The heaviest material
falling down division hopper C¹ is received onto sieve D.
The material falling down division hopper C falls into a trough U and is
conveyed down this trough to the tail end of machine where it joins the overtails of
sieve from division C₁ and is there subjected to another aspirating air current
drawn through aspirator channel E (see Figure 1). This aspirator channel has a
separate connection with the fan through two valves R³ one on either side of fan
casing. The overtails from sieve drop through spout E' on to either one or other
of the endless band conveyers F F¹.
Some of the light particles drawn up by the air which rises through the sieves
settles into a trough U₁ above the top of the trough.U and into other troughs U¹
along the two sides of the sieve frame.
The material falling down into division hopper C³ is finished offal as is also the
material deposited into hopper C* from aspirator E-these are conveyed through
valve shoots G G on to the tray U and from thence into a spout G' by which
they are conveyed outside the machine through suitable valve spouts.
The troughs or trays U U' are attached to sieve frame C and are vibrated to
and fro with it.
The purified material which passes through the sieve is collected in the hopper H
and drops between a number of vertical division boards H* between which are
valves Hany of which can be turned into such a position as to switch the material
into either one or the other of the conveyers F F by which they are conveyed
outside of the machine through spouts P P which are also provided with valves.
As much of the "sieve throughs as desired can thus be directed into one
conveyer and the overtails and remainder of the "sieve throughs" be directed into
the other conveyer:
"
All the air drawn through the various aspirators and through the sieves passes
through valves as before mentioned which are each provided with a deflector after
which it is drawn over baffle boards as indicated by the arrows and through fan B
passing out into dust collector I and through the baffle boards J J¹ J'J' JJ' into
the expansion chamber L..
+
In the modification of the machine shewn at. Figures 4 and 5 the sieve arrange
ment is omitted and the materials falling into each. division hopper are conveyed

page_text: .
away through separate spouts as indicated by the drawing—the machine so modified
forms a very useful machine for aspirating coarse tailings and overtails of break
scalpers drawing away all light dust and finished offal.
It is also a very cheap machine and very effective for purifying the coarse-
semolina taking little power and little room for the work done.
Having now particularly described and ascertained the nature of my said inven--
tion and in what manner the same is to be performed I declare that what I
claim is :-
:-
1. In apparatus used in purifying and sorting semolina, middlings and other such
substances the combination of the enclosed casing, the feed hopper at the upper
part of one end of this casing a series of receiving hoppers below the outlet from
the feed hopper, the fan for causing a stream of air to pass below the outlet from
the feed hopper and above the receiving hoppers-a vibrating sieve on to which the
materials pass from one of the receiving hoppers and the dust collecting chambers.
through which the air passes from the fan to below the feed hopper substantially as
described.
2. In apparatus used in purifying and sorting semolina, middlings and other such
substances, the combination of the enclosed casing, the feed hopper at one end of
the upper part of such casing, a series of receiving hoppers below the outlet from
the feed hopper, the fan at the upper part of the opposite end of the casing, a.
channel leading downwards from the fan outlet inclined boards with spaces between
through which air passes from this channel into another channel which leads along
the bottom of the casing and from which at the opposite end of the casing, the air
rises upwards and passes below the outlet from the feed hopper and over the top of
the receiving hoppers to the fan inlets substantially as described.
3. In apparatus used for purifying and sorting semolina middlings and other such.
substances in which the material is acted upon by streams of air and the air is.
used over and over again the arrangement herein described for separating dust.
from the air such arrangement consisting of the air channel I descending from the
fan inclined boards with spaces between through which air passes from the
channel and the dust catcher or hopper K at the bottom of the channel sub-
stantially as described.
4. Apparatus for purifying and sorting semolina, middlings and other such
substances constructed substantially as herein before described and illustrated in the
drawings annexed.
Dated this 16th dox of November 1902
W. W. WILLIS..