IMPROVEMENTS IN MIDDLINGS PURIFIERS
Year: 1881

page_text: LETTERS PATENT to Charles Denton Abel, of No. 28, Southampton
Buildings, Chancery Lane, in the County of Middlesex, for an Invention
of "IMPROVEMENTS IN MIDDLINGS PURIFIERS." A communication from
abroad by Carl Oberdorfer and Carl König, both of Vienna, in the Austrian
Empire
PROVISIONAL SPECIFICATION left by the said Charles Denton Abel at the
Office of the Commissioners of Patents on the 27th December 1881.
CHARLES DENTON ABEL of No. 28 Southampton Buildings Chancery Lane in
the County of Middlesex. "IMPROVEMENTS IN MIDDLINGS PURIFIERS." [A com-
munication from abroad by Carl Oberdorfer and Carl König both of Vienna in
the Austrian Empire.]
This Invention relates to an improved construction of middlings purifiers for
separating and sorting the various constituents of the middlings resulting from the
grinding process, such as the coarse meal or grits, the stive bran and husks.
For this purpose the middlings are led through a hopper into the top of a
chamber in which there are three compartments arranged vertically side by side, of
which two compartments are each formed with two series of horizontal bars or
louvre boards having inclined faces, and spaces between them, so that the air can
firstly pass from the outside through such spaces into the first compartiment, thence
into the second compartment, and from this through the said spaces into the third
compartment, the top of which communicates through a passage with an exhaust
fan by means of which currents of air are continually drawn through the com-
partments in the direction above indicated. The middlings being introduced
through the hopper into the top of the first compartment it falls in zig-zag
direction alternately from a bar of the one series on to one of the other series, and
the air currents passing transversely through the material as it falls effectually
stirs it up and loosens the various constituents from each other, the result of which
is that the coarse grits full down in the first compartment and are led away thence
through a shoot at bottom, while the lighter materials are carried through the air
spaces into the second compartment, where the finer grits fall down and are

page_text: conveyed away; the remaining material is again carried by the air currents
through the air spaces into the third compartment in which the husks are deposited
and also conveyed away, while the remaining stive or fine flour and the bran are
drawn through the above named passage into the exhaust fan and are propelled
thereby into the bran chamber, to be further treated in the known manner.
The air openings between the first series of bars are made to increase gradually
in width from top to bottom, so that only small air currents enter the compartment
at top while they gradually increase in force towards the bottom. The air spaces
between the next series of bars are slightly larger than those of the first series,
and they are in like manner increased in size in the next scries of the second
compartment. By this means the air currents are rendered weaker in the second
compartment than in the first, and again weaker in the third compartment than in
the second, and by this gradation of the strength of the currents the effectual
separation of the various constituents, as above described is brought about. The
passage leading from the third compartment to the exhaust fan is regulated by a
flap or valve, whereby also the force of the air currents through the other com-
partments is regulated. In order to effect a further more accurate regulation, so as
to adapt the machine to operate correctly on various different kinds of middlings,
the compartments are theinselves made adjustable in width by moving the several
series of bars or shelves which constitute the divisions of the compartments, farther
from or closer to each other. Thus, the farther these are moved apart, the weaker
are the air currents for one and the same adjustment of the exhaust passage,
serving in this case for the treatment of the lighter clases of middlings, while for
the coarser classes the series of bars are moved closer together so as to increase the
force of the currents.
The said adjustment is effected by arranging the-end-frames, to which the bars
are connected,-to-slide-with-pins in inclined slots in the casing.
The above described apparatus may either be constructed singly or in duplicate,
there being a series of the said compartments on each side of the exhaust passage,
and two such pairs of sets may be again combined in one machine, the two exhaust
passages being made to communicate with one and the same fan.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Denton Abel in the Great Seal Patent Office on the 20th June
1882.
CHARLES DENTON ABEL of No. 28 Southampton Buildings Chancery Lane in
the County of Middlesex. "IMPROVEMENTS IN MIDDLINGS PURIFIERS." A com-
munication from abroad by Carl Oberdorfer and Carl König, both of Vienna in
the Austrian Empire.
This Invention relates to an improved construction of middlings purifiers for
separating and sorting the various constituents of the middlings resulting from
the grinding process, such as the coarse meal or grits, the stive, bran and husks.
The construction and mode of operation of the machine will be readily
understood on reference to the accompanying Drawing, in which Fig. 1 shews &
longitudinal section, Fig. 2 an end view, and Fig. 3 a sectional plan.
The middlings fall from the hopper G on to the top bar of the row of bars A,
and from this on to the first bar of the row B, and so on in zig-zag direction
downwards. Between the bars of cach row are openings a through which a
current of air is drawn into the machine as indicated by the arrows, and these
air currents in passing transversely through the descending material, effectually
stir it up and carry with them the lighter particles into the compartment R¹ whilo
the heavy grits fall down in the compartment R. The air currents that pass with
the lighter particles through the air passages p into the compartment R¹ will have
become considerably weaker, and in this compartment will be deposited the
second grits, which is somewhat lighter than the first. All particles that are
lighter than this second grits pass with the air currents through the air passages
p into the compartment R². Here the husks are deposited while the stive together
with the bran escape through the passage L to the suction fan which discharges
the same into the bran chamber. The openings a are made of gradually increasing
width from top to bottom so that the air currents entering at top aro weak while
they gradually increase in strength towards the lower end. The air passages p¹
are slightly larger than those at p, and these are again slightly larger than those
at a. Consequently the air currents will be weaker in the compartment R³ than
in the compartment R¹ and these will be again weaker than those in the
compartment R. Consequently no first grits can be deposited in R because the
air currents will be too weak to carry them over. In the same way the second
grits cannot be deposited in R' and this will consequently be deposited free from
husks in R'.
The flap K closes more or less the opening O of the wind pipe L and thus
regulates the quantity of air drawn by the fan, so as to increase or decrease the
strength of the air currents passing through the compartments as may be required.
This inethod of regulation is however not sufficient to suit all the many different
descriptions of middlings. In order to afford further means of more accurate
regulation, the compartments R R R2 are capable of being increased or decreased
in width, for which purpose the rows of bars B and C are supported by pins in inclined
slots S so that by shifting them in their slots they are moved nearer together or
further apart. The wider the compartments are made, the weaker will be the air
currents, with one and the same position of the flap K, the machine will then be
suited for the finest descriptions of middlings. For acting on coarse middlings,
the rows of bars are moved nearer together in order to increase the strength of the
air currents. The regulation of the air currents can by this means be rendered so
accurate for every description of middlings, that the machine will effectually purify

page_text: the same at one operation, instead of requiring three or four consecutive operations
as in other machines.
The machine is shewn with the compartments in quadruple on the Drawing; it
may however be used singly or in duplicate. A single machine is capable of
operating upon about 400 lbs of middlings per hour. When the machine is in
duplicate or quadruple, the fan is connected directly thereto, but when a number
of single machines are employed they may be connected by pipes or passages with
a fan situated at any convenient part of the mill.
Havingthus described the nature of the said Invention and in what manner the
same is to be performed as communicated to me by my foreign correspondents :-
I claim
First Constructing middlings purifiers with a number of air inlets to the
several compartments, such air inlets being made to increase in size towards the
lower end of the machine, so as to admit air currents of increasing strength,
substantially as herein described.
Second. Constructing the compartments R R' R² of middlings purifiers of
rows of bars adjustable to and from each other so as to regulate the width of the
compartments according to the description of the middlings to be operated upon,
substantially as herein described.
In witness whereof I the said Charles Denton Abel have hereunto set my
hand and seal this Twentieth day of Juno in the year of our Lord One
thousand eight hundred and eighty-two.
CHAS. D. ABEL. (L.S.)