Improvements in Purifiers for Dunst, Middlings, Semolina, and such like Cereal Products.
Year: 1892

page_text: Date of Application, 19th Aug., 1892
Complete Specification Left, 17th June, 1893-Accepted, 22nd July, 1893
TRUVIDIONAL SPECIFICATION.
Improvements in Purifiers for Dunst, Middlings, Semolina, and such
like Cereal Products.
I, JAMES HIGGINBOTTOM of 32, Seel Street, Liverpool in the County of
Lancaster, Milling Engineer do hereby declare the nature of this invention to be
as follows:-
This invention relates to purifiers in which the air discharged from the machine is
delivered free from dust.
In carrying out this invention-
Firstly. I preferably use a longitudinal air expansion and dust depositing
chamber with collecting or discharging apparatus therein at the lower part of the
chamber, placed over the vibrating sieve as described in the Patent Specification
No. 6676 of 1886.
Secondly. I form the inwardly sloping sides of such chamber with nozzles for the
admission of air and dust from the sieve as described in the Specification No. 14711
of 1888 and No. 11831 of 1889.
Thirdly. I form the number and shape of the nozzles in such manner as to cause
an evenly distributed or minutely divided downward current of the air and dust
into the expansion chamber, for the better deposition of the dust.
Fourthly. I arrange the air and dust arising from the aspirator to the overtails
of my well known Victoria purifier to pass into the above mentioned expansion
chamber through a partition, or partitions, fitted with nozzles as above described.
Fifthly. In some cases, I arrange the nozzles upon the vibrating tray of the
purifier described in the Specification No. 14711 of 1888, so that the dust in the
air leaving the vibrating nozzles, is caused to impinge upon a vertical or nearly
vertical surface placed in front of the nozzle, in such manner that the fine dust
contained in the air is caused to impact and to form an adherence or growing film
upon the face of such surface, and until the film grows to such a thickness, that it
can no longer adhere to the surface but falls away by its own weight, such falling
away is aided by the vibration of the tray.
Sixthly. In some cases I apply the above mentioned impact surfaces to the
nozzles upon the stationary sides and partitions of the expansion chamber, and in
such case, I aid the falling away of the films of dust by means of a knocking
apparatus applied to such stationary nozzles.
Seventhly. In some cases, I use one or more expansion chambers, placed side by
side, either longitudinally or transversely over the sieve of the machine, with dust
collecting or discharging apparatus therein; and in some cases I use one or more
secondary expansion or deposition chambers placed inside the primary chamber
in such manner that the air and dust leaving the primary chamber may be again
expanded and provided with depositing surface and discharging apparatus in a
secondary chamber or chambers.
Eighthly. In some cases I use regulating slides or valves between such primary
and secondary chambers.
Ninthly. In some cases I connect the primary chamber direct to the conduit
leading to the exhaust fan, and in other cases I prefer to cause the air and dust
to pass from the primary chamber to the secondary chamber or chambers and from
thence to the conduit leading to the exhaust fan.
Tenthly. In every case whether I use a primary chamber or chambers or primary
chambers and secondary chambers with valves between the same, I prefer to use a
main regulating slide or valve or valves in the air conduits leading to the exhaust
fan or fans. Such main valves I prefer to be set as close to the fan or fans as
possible, in such manner that the said main valve or valves shall be able to fully

page_text: control the quantity of air passing through the expansion chambers and their air
passages and adjusting valves in the interior of the machine.
It is most important that the exhaust fan or fans should be of such dimensions
and that it should run at such a speed as will enable the fan to discharge several
times more air (if such air could get to the fan) than is required by the purifier for
accomplishing the desired degree of purification.
The slides or valves between such fan or fans and the expansion chamber or
chambers are for the purpose of checking the quantity of air flowing through the
machine to the exhaust fan or fans, and thereby I attain a more steadily maintained,
or a more uniform degree of exhaustion in the conduit or conduits, and in the
expansion chamber or chambers with the results―
Firstly. That the air passing through the gauze covering on the vibrating sieve
is kept more uniform throughout the entire area of the sieve.
Secondly. That the deposition of the dust is more effectually secured in the
expansion and depositing chambers.
In some cases, I combine the foregoing together with a flexible connection to
sieve and frame, and with a sieve built up in separate sections as described in
the Specification No. 2094 of 1879, also together with the invention described in
Specifications No. 793 of 1889, namely, Dead sheets applied to the gauze coverings
of purifier sieves, No. 12692 of 1889, namely, Ribbed sieves applied to the gauze
coverings of purifier sieves, No. 18643 of 1889, namely, the vertical dressing and
purifying machine therein described.
No. 2284 of 1890, namely, the reducing, separating and purifying machine
therein described.
No. 11820 of 1890, namely Intensors applied to the sieves of purifiers.
D
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Purifiers for Dunst, Middlings, Semolina, and such
like Cereal Products.
I, JAMES HIGGINBOTTOM of 32 Seel Street, Liverpool in the County of
Lancaster, Milling Engineer, 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 has for its object improvements in that class of machinery set
forth in my prior Patents No. 2094 of 1879, No. 14711 of 1888, No. 793 of 1889,
No. 11831 of 1889, 12692 of 1889, No. 18643 of 1889, No. 2284 of 1890 and
No. 11820 of 1890, and most of the novelties herein set forth can be used in
conjunction with nearly all these inventions.
for
In the separating of middlings or the sieving of flour it has been found that a
series of troughs placed as near together as possible to prevent the spaces between
getting choked, and as close to the sieve as possible, is an excellent means,
separating the dust. The air aspirated through the sieve carries up the dust
through the narrow space between the troughs; but spreading out above them, the
heavier particles of dust fall into the troughs.
Some years ago, I found, that by the bridging over part of the space at intervals
between the troughs so that the area of exit for the air should be curtailed both
longitudinally and transversely and instead of long slits, substituting square or
round holes (with troughs between), the dust is separated in a far greater measure
from the air, as the area it has to settle on and to expand in, is far greater
relatively to the area of exit between the troughs than is the case when long slits
are used.
I further found that if hoods, nozzles, or bonnets were arranged above

page_text: these holes so as to direct the escaping air into the channels between the holes,
the better effect was produced and still further fine dust separated from the air.
I have now discovered that if air containing this dust be driven with sufficient
velocity against a flat surface, the dust impinging on that flat surface sticks thereto
and forms a kind of felt, which as it increases in weight drops off and that in this
way nearly the entire dust is separated. Experimenting on this discovery, I have
applied it to the tray of nozzles placed above the vibrating sieve as described in
my Patent No. 14711 of 1888 and my Patent No. 11831 of 1889.
I also use my nozzle invention as above mentioned for obtaining a better
deposition of fine dust in the upper portion of a purifier, namely, in that portion or
portions of the machine above the sieve through which the air must pass before it
is discharged on the outside of the machine. I place the nozzles in such portions
of the machine, in such a manner that the air is subdivided into a suitable number
of streams, and so that such streams may be contracted directed or expanded for
the purpose of causing a better deposition of the fine dust contained in the air.
I also arrange the air after its passage through the nozzles in the upper portions
of the machine, so that it shall be deflected in its passage to the exhaust fan
through primary and secondary expansion and deposition chambers for the further
deposition of any fine dust which may remain in the air.
The invention will be understood by reference to the accompanying drawings, in
which,
Figure 1 is a section of a portion of a tray of nozzles placed over the sieve of a.
purifier and vibrating therewith ;
Figure 2 a plan of Figure 1;
Figure 3 a longitudinal vertical section through a purifier constructed in:
accordance with my invention ;
Figure 4 a horizontal sectional plan of Figure 3;
Figure a transverse vertical section of Figure 3 taken on the line A A;
Figure 6 a transverse vertical section of Figure 3 taken on the line B B ;
Figure 7 a part elevation of one of the inwardly sloping sides of depositing
chamber G with its nozzles drawn to a scale of full size, arranged to discharge in a.
downward direction;
Figure 8 a sectional plan of Figure 7;
Figure 9 a vertical section of Figure 7;
Figure 10 a part elevation of the inwardly sloping sides of the depositing
chamber G with nozzles arranged to discharge in a slanting direction against an.
impact surface; and
Figure 11 a sectional plan of Figure 10.
Referring to Figures 1 and 2.
A, is a tray pierced with a large number of holes, placed almost immediately
above the sieve, B, conical or pyramidal nozzles fixed thereto, covering the holes,.
C, a hood placed over the top of the nozzles to direct the stream of dusty air,.
D, a plate placed approximately at right angles to the effluent streams. The:
stream of air beating against this plate deposits almost all its fine dust particles on:
the plate as a sort of adhering felt. This felt would continue to increase in size.
until it stopped up the nozzles but for the fact that the entire tray is kept in rapid
vibration, being attached to the vibrating sieve. The consequence of this is that.
the felt increases in thickness, until its weight detaches it from the surface of the
plate and it falls down on to the sloping tray, and is gradually carried by the.
shaking, along the sloping surface of the tray, between the nozzles, in a direction.
parallel to the plates until it falls off at the end into any suitable receptacle.
the meantime a fresh film or felt forms opposite the nozzles. E E and F are struts
or ties to support the plates to hold the whole firmly fixed together.
In
The invention, when applied for depositing any fine dust which may remain in
suspension in the air after impact with the aforesaid surfaces, carried into effect
in the following manner :-
Firstly. I preferably use a longitudinal air expansion and dust depositing

page_text: chamber G with collecting or discharging apparatus H therein at the lower part
of the chamber placed over the vibrating sieve as shown in the Figures 3, 4, 5
and 6.
Secondly. I form the inwardly sloping sides of such chamber with nozzles I for
the admission of air and dust as shown in Figures 7, 8 and 9, Figures 3, 4, 5 and 6,
and Figures 10 and 11.
Thirdly. I form the number and shape of the nozzles in such manner as to cause
an evenly distributed or minutely divided downward current of the air and dust
into the expansion chamber for the better deposition of the dust. I prefer the
dimensions of these nozzles to be about the size and shape as shown in Figures 7,
8, 9, 10 and 11, and I prefer to place as many nozzles on the sloping sides of the
chamber G as will make the united area of the discharge orifices of the nozzles
equal to about of the area of the vibrating sieve.
Fourthly. I arrange the air and dust (arising from an aspirator J treating the
overtails of the purifier sieve) to pass through a series of nozzles K placed in the
end of the depositing chamber G. Such nozzles K are made similar to the nozzles
in the sloping side of the chamber, and are placed to discharge the air and dust in
a downward direction. I also make a sufficient number of the nozzles so that the
united area of the nozzle discharges shall be about twice the area of the uptake L
of the aspirator, whereby undue acceleration of the air currents, which would tend
to prevent the deposition of the dust, is prevented.
Fifthly. In some cases, I apply the above mentioned impact surfaces D to the
nozzle Cupon the stationary sides of the expansion chamber G, and I aid the
falling away of the films of dust by placing the discharge orifices of the nozzles so
as to blow in a direction nearly at right angles against the surfaces placed in a
slanting direction, as illustrated in Figures 10 and 11. Also, in some cases,
I use
a knocking apparatus applied to such stationary nozzles and surfaces to assist in
causing the film of dust to fall off into the bottom of the depositing chamber.
For further depositing the dust which may remain in the air after its passage
through the nozzles, I use one or more expansion chambers G placed side by side
either longitudinally or transversely over the sieve of the machine, with dust
collecting or discharging apparatus therein; and, in some cases, I use one or more
secondary expansion or deposition chambers M M placed inside the primary
chambers Gin such manner that the air and dust leaving the primary chamber G
may be again expanded and provided with depositing surfaces and discharging
apparatus N N in the secondary chamber or chambers M M. Such discharging
apparatus being the well known balanced air flap discharge N, as illustrated in
Figures 3, 4, 5 and 6, which discharges the deposited dust into the primary
chamber or chambers G.
The dust from the primary chamber G is collected and removed by the worm or
creeper H to the outside of the machine, as is well understood by the milling
trade. In some cases, I use regulating slides or valves between such primary and
secondary chambers to regulate the volume or velocity of the air passing from the
primary to the secondary chamber or chambers. In some cases, I connect the
primary chamber G direct to the conduits QQ leading to the exhaust fan or
fans 00. In other cases I prefer to cause the air and dust to pass from the
primary chamber to the secondary chamber or chambers M M and from thence to
the conduits QQ leading to the exhaust fan or fans. In every case, whether I use
a primary chamber or chambers, or primary chambers and secondary chambers
with valves between the same, I prefer to use a main regulating slide or valve or
valves PP in the air conduits leading to the exhaust fan or fans. Such main
valves I prefer to be set as close to the fan or fans as possible, in such manner that
the said main valve or valves shall be able to fully control the quantity of air
passing through the expansion chambers and their air passages and adjusting
valves in the interior of the machine. The controlling of the main valves is done
on the outside of the machine by means of the handles R R.
It is most important that the exhaust fan or fans should be of such dimensions

page_text: and that they should run at such a speed as will enable them to discharge several
times more air (if such air could get to the fan) than is required by the purifier for
accomplishing the desired degree of purification.
The slides or valves P P, between such fan or fans and the expansion chamber
or chambers, are for the purpose of checking the quantity of air flowing through
the machine to the exhaust fan or fans; and thereby I attain a more steadily
maintained or a more uniform degree of exhaustion in the conduit or conduits and
in the expansion chamber or chambers, with the results-
Firstly. That the air passing through the gauze coverings on the vibrating sieve
is drawn by the exhaust fan more uniformly throughout the entire area of the
Bieve:
Secondly. That the deposition of the dust is more effectually secured in the
expansion and depositing chambers.
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 a purifier for dunst, middlings, semolina and other like cereal products, the
combination, with nozzles or other appliances for collecting dust, of impact dust
depositing surfaces substantially as and for the purposes described.
2. The combination of nozzles and impact surfaces for dust collecting when used
in purifiers or other analogous dust collecting apparatus.
3. In a purifier, in combination with a sieve and collecting channels, a tray of
nozzles or other means for collecting dust near the sieve, a series of nozzles placed
in the sides of a dust depositing chamber or chambers in the upper portion of the
machine, substantially as described.
4. In a purifier having an aspirator to the overtails, the combination, with the
aspirator and a dust depositing chamber, of a series of nozzles placed in the side of
the chamber substantially as and for the purpose set forth.
5. In combination with a sieve and collecting chamber or chambers, one or more
secondary chambers opening out of the primary chambers having trapped dust
exits and communicating, by means of a valved passage, with the exhaust.
6. In a purifier, the combination, with sieves and nozzles and collecting chambers,
of main regulating valves, substantially as described.
Dated this 15th day of June 1893.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham, and London, Patent Agents.