IMPROVEMENTS IN MIDdlings PurifIERS, WHICH IMPROVEMENTS ARE ALSO PARTLY APPLICABLE TO SORTING, SEPARATING, AND GRINDING MACHINERY GENERALLY
Year: 1881

page_text: LETTERS PATENT to William Henry Dickey, of Jackson, Michigan, in the
United States of America, but at present of No. 26, Mark Lane, in the City
of London, for an Invention of "IMPROVEMENTS IN MIDdlings PurifIERS,
WHICH IMPROVEMENTS ARE ALSO PARTLY APPLICABLE TO SORTING, SEPARATING,
AND GRINDING MACHINERY GENERALLY." Partly a communication from
abroad by George T. Smith, of Jackson, Michigan, in the United States of
America.
PROVISIONAL SPECIFICATION left by the said William Henry Dickey at
tho Office of the Commissioners of Patents on the 3rd June 1881.
"
WILLIAM HENRY DICKEY, of Jackson, Michigan, in the United States of
America, but at present of No. 26, Mark Lanc, in the City of London. IMPROVE-
MENTS IN MIDDLINGS PURIFIERS, WHICH IMPROVEMENTS ARE ALSO PARTLY
APPLICABLE TO SORTING, SEPARATING, AND GRINDING MACHINERY GENERALLY."
[Partly a communication from abroad by George T. Smith, of Jackson, Michigan,
in the United States of America.]
This Invention relates mainly to improvements in middlings purifiers, and
consists, first, in providing a device by means of which the quantity of material fed
into the purifier for treatment is automatically regulated with reference to the
quantity of middlings or other material delivered into a hopper or other receptacle
from which the middlings or other material fed to the purifier is supplied.
In constructing this device the hopper or other receptacle into which the
middlings or other material is received before passing to the purifier for treatment
may be made with a shelf or flap suitably placed inside the hopper, and of a size
nearly equal to the hopper or other receptacle at the point where it is attached, as
will be explained. One edge of this shelf may be hinged to the side of the hopper
or other receptacle, and the other edge left free, and arranged to move upwards
and downwards at the time and for the purpose hereinafter described. On the side
of the hopper opposite the one to which the shelf is hinged a fillet may be placed,
and made to project a suitable distance into the hopper, being arranged above tho
shelf, and forming a stop for it to shut against. Rods may be attached to tho

page_text: underside of this shelf, and made to project downwards and out through one side
of the hopper or other receptacle, where they will be made to engage with levers
to rotate a shaft, or to impart motion to other mechanism, by means of which a
feed gate through which the middlings or other material must pass to the purifier
will be opened or closed, thus admitting more or less material to the purifier, as
will be presently explained. The feed gate and the ways or bearings in which it
moves is properly constructed with a view to being opened or closed by the means
above indicated. In operation the hinged shelf would open downwards whenever
it was loaded with a certain quantity of material, less than would be sufficient to
overflow the hopper or other receptacle, and would thus allow the material to pass
to the feed roll or other feeding device, by means of which it is directed through
the feed gate already mentioned. At the same time this downward movement of
the shelf would cause the rods attached to its underside to be thrust further
through the side of the hopper or other receptacle, and these rods being in con-
nection with the levers, shaft, or other mechanisin for opening or closing the feed
gate, as already described, the motion imparted to these devices would result in
the feed gate being opened in proportion to the distance the shelf was depressed.
Attached to the feed gate would be springs or weights, so arranged that the
opening of the gate would compress or raise them, and these weights or springs
reacting on the hinged shelf through the mechanism already described would causo
it when discharged of its load to close upwards against the fillet. It will thus be
seen that the weight of the material received into the hopper or other receptacle
(or into this shelf which forms a bottom to the hopper) would be made to regulate
the quantity of material passing through the feed gate to the purifier in direct
proportion to itself.
The feeding devico herein described is equally applicable to roller mills, to
dressing reels, and to many kinds of sifting, separating, grinding, and other
machines.
In making this feeding device I do not limit myself to the precise details, of
construction herein indicated, but propose to make it in the simplest possible
manner on the principle of causing the weight or quantity of material to bo
treated on any purifier or other machine to regulate the rate of feed to such purifier
or other machine in proportion to itself. The motion of the regulating flap or
shelf may be imparted to the feed gate by means of rods, straps, or cords passing
up through the hopper instead of downwards.
The second improvement consists in providing a device for tightening the silk
coverings on the sieves of purifiers and other similar machines. This is effected by
attaching fillets of wood to the side and end ribs of a purifier sieve frame by
hinges, bolts, screws, or other suitable ineans in such a manner that the fillets can
be set away from or towards the ribs. In operation when a silk covering is put
on to a purifier sieve frame the fillets will be set soine little distance away from
the ribs of the frame, and securely fastened in place by the bolts, rods, screws, or
other device by which they are attached to the ribs; the silk will then be
stretched tight and tacked to the fillets. Whenever the silk becomes loose by the
stretching of its threads it may be tightened by adjusting the fillets to which it is
fastened nearer to the ribs of the sieve frame by the means already described, the
effect of this adjustment being to move the fillets farther apart, and accordingly to
stretch the silk anew. The stretching bolts or tics may be provided with springs,
stretching the silk automatically.
Generally speaking middlings purifiers are either "air" or "sieve" purifiers, the
foriner depending altogether on air currents of different degrees of velocity, or on n
combination of such air currents with the centrifugal force for the purification of
middlings, and the latter receiving the material to be treated on to a sieve covered
with silk bolting cloth of suitable degrees of fineness, through which an air current
is made to pass upwards for the purpose of assisting the purification, as is well
understood. Each of the above types of purifiers is adaptod to particular classes of
middlings, but neither is suited to handle economically all sizes and conditions of

page_text: such material, and the "breaks" of rolls and other machines now coming to bo
largely used in gradual-reduction systems of milling contain the finest as well as
the coarsest middlings mixed together. The third improvement consists in so
constructing and combining a middlings purifier that it shall be adapted to properly
treat the "meal" or "breaks" from rolls and other gradual reduction machines,
containing as it does the coarsest as well as the finest middlings. For this purpose
I construct what is technically known as the "tail board" of a sieve purifier with
several sets of louvre boards enclosed within it. The tail board opens at its upper
end into the eye of an exhaust fan, and by this means air currents are induced
between each pair of the louvre boards. The velocities of the currents between the
several pairs of louvre boards are arranged to be regulated separately by suitable
valves controlling the amount of air admitted between any pair. In operation the
meal from any "reduction" of rolls or other grinding machine, after having had
the flour sifted out, would be received on to the sieve of the purifier in the
ordinary manner, and the silk of which this sieve is composed will be of such
numbers as will permit the passage of all middlings small enough to need no
further reduction until the final one. The material will be caused to flow along
the sieve in the ordinary way, and as it traverses the silk all middlings of the Bizo
indicated above will be sifted through this cloth. All material of larger size will
be delivered over the tail of the sieve into the "tail board," where it will fall in a
broad thin stream on to the several pairs of louvre boards in succession, being
treated as it passes the openings between each pair to air currents, increasing in
velocity from the first to the last openings, whereby particles of correspondingly
different sizes and weights will be removed by the air currents passing through
each of the said openings in succession. It is evident that a machine constructed
as herein described will be applicable to the treatment of many other classes of
material than that named where it is desirable to mako separations with reference
to size and specific gravity.
The fourth improvement consists in so combining and constructing a middlings
purifier that it shall contain the following features in addition to the vibrating
sieve conveyors, fan, &c., usually found in such machines, viz.:-An air chamber
above the sieve divided into several compartments by means of transverso
partitions, these compartments having no communication with each other; openings
cut through the side of the machine to admit air currents beneath the sieve; a
valve opening from each of the compartments above mentioned into the fan
chamber, by means of which an air current of a high degree of velocity can be
made to pass upwards through the silk on the sieve under any one of these com-
partments without in any manner disturbing the flow of a very gentle current,
which may at the same time be passing upwards through the silk on the sieve
under an adjacent compartment. In the upper part of each of these compartments
is a testing pocket or settling chamber, through which the air currents are made
to pass on their way to the fan, and where they are caused to deposit the heaviest
particles they may have carried up from the material, being treated on the silk of
the sieve. A brush is attached to an endless chain, and mounted on ways, by
which it is adjustable to or from the undersurface of the silk on the sieve frame,
motion being imparted to the chain by means of star wheels on a shaft provided
for the purpose and driven with the rest of the machine in such a direction and
at such a speed that the brush will sweep the under side of the silk from head to
tail of the sieve at very brief intervals. Also in combination with the above the
automatic feeding device already described herein, the device for tightening the
silk of the sieve, as described herein, the construction of louvre boards in the tail
board of the purifier, and the arrangement for inducing air currents and regulating
their velocity through the openings between the several pairs of louvre boards, as
already detailed herein.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Henry Dickey in the Great Seal Patent Office on the
3rd December 1881.
WILLIAM HENRY DICKEY, of Jackson, Michigan, in the United States of
America, but at present of No. 26, Mark Lane, in the City of London. " IMPROVE-
MENTS IN MIDDLINGS PURIFIERS, WHICH IMPROVEMENTS ARE ALSO PARTLY
APPLICABLE TO SORTING, SEPARATING, AND GRINDING MACHINERY GENERALLY."
Partly a communication from abroad by George T. Smith, of Jackson, Michigan, in
the United States of America.
This Invention relates mainly to improvements in middlings purifiers, and
consists, first, in providing a device by means of which the quantity of material fed
into the purifier for treatment is automatically regulated with reference to tho
quantity of middlings or other material delivered into a hopper or other receptacle
from which the middlings or other material fed to the purifier is supplied.
In constructing this device the hopper or other receptacle into which the
middlings or other material is received before passing to the purifier for treatment
may be made with a shelf or flap suitably placed inside the hopper, and of a size
nearly equal to the hopper or other receptacle at the point where it is attached, as
will be explained. One edge of this shelf may be hinged to the side of the hopper
or other receptacle, and the other edge left free and arranged to move upwards and
downwards at the time and for the purpose hereinafter described. On the side of
the hopper opposite to the one to which the shelf is hinged a fillet may be placed,
and made to project a suitable distance into the hopper, being arranged above the
shelf, and forming a stop for it to shut against. Rods may be attached to the
underside of this shelf, and made to project downwards and out through one side
of the hopper or other receptacle, where they will be made to engage with levers
to rotate a shaft or to impart motion to other mechanism, by means of which a
feed gate through which the middlings or other material must pass to the purifier
will be opened or closed, thus adınitting more or less material to the purifier, na
will be presently explained. The feed gate and the ways or bearings in which it
moves is properly constructed with a view to being opened or closed by the means
above indicated. In operation the hinged shelf would open downwards whenever
it was loaded with a certain quantity of material less than would be sufficient to
overflow the hopper or other receptacle, and would thus allow the material to pass
to the feed roll or other feeding device, by means of which it is directed through
the feed gate already mentioned. At the same time this downward movement of
the shelf would cause the rods attached to its under side to be thrust further
through the side of the hopper or other receptacle, and these rods being in con-
nection with the levers, shaft, or other mechanism for opening or closing the feed
gate, as already described, the motion imparted to these devices would result in
the feed gate being opened in proportion to the distance the shelf was depressed.
Attached to the feed gate would be springs or weights so arranged that the opening
of the gate would compress or raise them, and these weights or springs reacting on
the hinged shelf through the mechanism already described would cause it when
discharged of its load to close upwards against the fillet. It will thus be seen that
the weight of the material received into the hopper or other receptacle (or into
this shelf which forms a bottom to the hopper) would be made to regulate the
quantity of material passing through the feed gate to the purifier in direct
proportion to itself.
The feeding device herein described is equally applicable to roller mills, to
dressing reels, and to many kinds of sifting, separating, grinding, and other

page_text: In making this feeding device I do not limit myself to the precise details of
construction herein indicated, but propose to make it in the simplest possible
manner on the principle of causing the weight or quantity of material to be treated
on any purifier or other machine to regulate the rate of feed to such purifier or
other machine in proportion to itself. The motion of the regulating flap or shelf
may be imparted to the feed gate by means of rods, straps, or cords passing up
through the hopper instead of downwards.
The second improvement consists in providing a device for tightening the silk
coverings on the sieves of purifiers and other similar machines. This is effected
by attaching fillets of wood to the side and end ribs of a purifier sieve frame by
hinges, bolts, screws, or other suitable means in such a manner that the fillets can
be set away from or towards the ribs. In operation when a silk covering is put
on to a purifier sieve frame the fillets will be set some little distance away from
the ribs of the frame, and securely fastened in place by the bolts, rods, screws, or
other device by which they are attached to the ribs; the silk will then be stretched
tight and tacked to the fillets. Whenever the silk becomes loose by the stretching
of its threads it may be tightened by adjusting the fillets to which it is fastened
nearer to the ribs of the sieve frame by the means already described, the effect of
this adjustment being to move the fillets farther apart, and accordingly to stretch
the silk anew. The stretching bolts or ties may be provided with springs stretching
the silk automatically.
-
Generally speaking middlings purifiers are either "air" or "sieve" purifiers, tho
former depending altogether on air currents of different degrees of velocity, or on a
combination of such air currents with centrifugal force for the purification of
middlings, and the latter receiving the material to be treated on to a sieve covered
with silk bolting cloth of suitable degrees of fineness, through which an air current
is made to pass upwards for the purpose of assisting the purification, as is well
understood. Each of the above types of purifiers is adapted to particular classes of
middlings, but neither is suited to handle economically all sizes and conditions of
such material, and the "breaks" of rolls and other machines now coming to be
largely used in gradual-reduction systems of milling contain the finest as well as the
coarsest middlings mixed together.
The third improvement consists in so. constructing and combining a middlings
purifier that it shall be adapted to properly treat the "meal" or "breaks" from roll
and other gradual-reduction machines, containing as it does the coarsest as well as
the finest middlings. For this purpose I construct what is technically known as the
"tail board" of a sieve purifier, with several sets of louvre boards enclosed within it.
The tail board opens at its upper end into the eye of an exhaust pan, and by this
means air currents are induced between cach pair of the louvre boards. The
velocities of the currents between the several pairs of louvre boards are arranged to
be regulated separately by suitable valves controlling the amount of air admitted
between any pair. In operation the meal from any "reduction" of rolls or other
grinding machine, after having had the flour sifted out, would be received onto the
sieve of the purifier in the ordinary manner, and the silk of which this sieve is
composed will be of such numbers as will permit the passage of all middlings small
The material will be
enough to need no further reduction until the final one.
caused to flow along the sieve in the ordinary way, and as it traverses the silk
all middlings of the size indicated above will be sifted through this cloth. All
material of larger size will be delivered over the tail of the sieve into the "tail
board," where it will fall in a broad thin stream on to the several pairs of louvre
boards in succession, being treated as it passes the openings between each pair to
air currents, increasing in velocity from the first to the last openings, whereby
particles of correspondingly different sizes and weights will be removed by the air
currents passing through each of the said openings in succession. It is ovident
that a machine constructed as herein described will be applicable to the treatment
of many other classes of material than that named, where it is desirable to make
separations with reference to size and specific gravity.

page_text: The fourth improvement consists in so combining and constructing a middlings
purifier that it shall contain the following features, in addition to the vibrating
sieve, conveyors, fan, &c., usually found in such machinery, viz. :-An air chamber
above the sieve divided into several compartments by means of transverse partitions,
these compartments having no communication with each other; openings cut
through the side of the machine to admit air currents beneath the sieve; a valve
opening from each of the compartments above mentioned into the fan chamber, by
means of which an air current of a high degree of velocity can be made to pass
upwards through the silk on the sieve under any one of these compartments,
without in any manner disturbing the flow of a very gentle current, which may at
the same time be passing upwards through the silk on the sieve under an adjacent
compartment. In the upper part of each of these compartments is a testing pocket
or settling chamber, through which the air currents are made to pass on their way
to the fan, and where they are caused to deposit the heaviest particles they may have
carried up from the material being treated on the silk of the sieve. A brush is attached
to an endless chain, and mounted on ways by which it is adjustable to or from the
under surface of the silk on the sieve frame, motion being imparted to the chain
by means of star wheels on a shaft provided for the purpose, and driven with the
rest of the machine in such a direction and at such a speed that the brush will
sweep the underside of the silk from head to tail of the sieve at very brief intervals.
Also in combination with the above, the automatic feeding device already described
herein; the device for tightening the silk of the sieve as described herein; the
construction of louvre boards in the tail board of the purifier, and the arrangement
for inducing air currents and regulating their velocity through the openings
between the several pairs of louvre boards as already detailed herein.
In order that the said Invention may be more clearly understood I shall now
proceed to particularly describe the same, and for that purpose shall refer to the
accompanying Drawings, like letters indicating corresponding parts in all the
Figures.
The feeding device is shown in transverso vertical section in Fig. 1, A being the
hopper into which the middlings to be treated by the purifier are delivered by an
elevator, conveyer, or other means. B is the shelf or flap hinged at one edge to
the side of the hopper. This shelf may be made nearly the width of the hopper,
and arranged to shut against a fillet fastened to that side of the hopper opposito
the one to which it is hinged, or it may be made of less width and the fillet
omitted which is the manner of construction shewn in the Drawings. C is the
rod attached to the underside of the shelf or flap, and extending down and out-
wards through the side of the hopper where it engages with D a lever secured to
the feed gate E. On rod C is placed the coil spring F and the thumb nut G, by
means of which the weight required to move flap B is regulated. E is the feed
gate secured at each end to the hinges H which are pivotted at J. When closed
the lower edge of the feed gate rests against the feet roll L. By means of thumb
nut G the lower edge of the feed gate can be set any desired distance away from
tho feed roll, and the distance thus determined will not be lessened by the sub-
sequent automatic regulation of the feed. K is & webbing of calico or canvas
secured to the free edges of the shelf or flap and the sides and ends of the hopper
in such a manner as will prevent any middlings getting under the shelf to
interfere with its action. In practice the operation of this device is as follows:-
The hopper A being filled above the level of the shelf B, the material resting on
it (B) will cause it to be depressed inore or less in proportion to the weight of
such material, and as it moves downwards the feed gate will be raised corre-
spondingly through the action of rod C on lever D. When the accumulated
material or some portion of it has passed under the feed gate the coil spring F
will cause the shelf to resume its position, thus diminishing the opening under the
feed gate. It is evident that this feeding device is equally applicable to roller
mills, dressing silks, and to sifting, sorting, and grinding machines generally.
The silk tightening device is represented in Fig. 4. A' is one of the side stringers

page_text: of the sieve frame of a middlings purifier; B¹ is a fillet of same length as A², and
firmly secured to its inner side by means of nails, screws, or in any other convenient
maoner; D¹ is a second fillet of same length as B', and is placed directly under-
neath B and in contact with its lower edge; C' is a bolt passing through the
transverse slot F in fillet D', and through a hole in fillet B'; E' is a bolt passing
horizontally through stringer A' and fillet D', and having a thumb nut on its
threaded end. Bolts E' are placed from one to two feet apart, and bolts C¹ are
used at corresponding distances. It will be seen that fillet D', by means of the slot F',
can be adjusted either towards or away from stringer A. The silk covering of the
sieve is tacked or otherwise secured to the lower edge of D'. Fillets like those
above described will be attached to the stringer formning the side of the sieve frame
opposite that shewn in the Drawing, as will be readily understood by reference to
Fig. 3. In operation the working of the device is as follows:-Fillets D¹ (Fig. 3)
are set at some little distance away from stringers A¹, and accordingly nearer to
each other, and are firmly secured in their places by tightening the nuts or bolts C'.
The silk, which has been made of such size that it will require to be tightly
stretched in order to reach from one fillet to the other is fastened to lower edges of
D', D. When after having been some time in use the silk becomes too slack it
may be tightened by loosening the nuts on bolts C1, and turning the nuts on bolts E'
so as to force fillets D' nearer to stringers A', and accordingly further apart, which
will stretch the silk anew. When the silk is sufficiently stretched fillets D' will bo
secured in place by again tightening the nuts on bolts C', as already described.
The silk is stretched lengthwise in the same manner and by the same means as
above set forth. It is apparent that the fillets might be secured to the sieve framo
stringers by means of hinges, threaded rods, or in any other manner which would
permit of their having the necessary adjustment towards and away from each other.
Fig. 2 is a longitudinal vertical section of a middlings purifier so constructed
and combined as to adapt it to the treatment of the "breaks" of rollers and other
gradual-reduction machines containing as this "meal"" does, the finest as well as
the coarsest middlings. The material to be treated is received into the hopper A,
and fed on to the siove A¹ through the feed gate E, as previously described. The
material is caused to flow along the sieve in the usual manner, and the clothing of
the sieve (preferably wire in this case) will be of such a degree of fineness as will
admit of the passage through it of all middlings small enough to require no further
reduction before flouring. Such middlings as pass through the sieve will be
directed by the gather boards M, M, (Fig. 3) into the conveyors G¹ (Fig. 3), from
whence, if desired, they may be drawn directly to the rolls or stones employed for
final reduction. The balance of the material as it passes over the tail of the sievo
falls in a broad thin sheet on to the louvre boards H, H, H', in succession,
between which air currents of varying degrees of intensity are made to pass in the
direction indicated by the arrows, removing bran particles and such other impurities
as from their size or character it was impossible to separate on the sieve; this
action being substantially the same as the operation of "aspirator" purifiers as
commonly constructed.
Referring to the fourth improvement, P, P, P, &c., &c., Fig. 1, are the compart-
ments above the sieve; S, S, S, &c., &c., are the testing pockets or dust sottling
chambers constructed in the upper part of the compartments P, &c.; A², A², A¹
&c., &c., are the valves opening into the fan chamber, by the adjustment of which
the force of the air current through any compartment is regulated; D' is the brush
(see also Fig. 3); E2, the ways on which it rosts, and by means of which it can bo
adjusted towards or away from the silk; F2, the star wheels; and K¹, the chain by
which it is driven; letters A to L inclusive designato the parts of the feeding
device already fully described; letters A¹ to D' inclusive indicate the parts and
arrangement of the silk stretching device already sufficiently described; and letters
Hand I the arrangomont of the louvre boards in the "tail board "of the purifier as
set forth; L, L', Fig. 3, are the openings cut through the sides of the purifier to
admit air underneath the sieve.

page_text: By an examination of Fig. 2 it will be seen that all the features herein mentioned
are to be found in it, although for greater convenience in describing them more
particular reference has been made to other Figures in which they are represented.
Having now described the said Invention, and indicated the manner in which
the same is or may be carried into effect, what I consider new and claim as the
Invention secured to me by the herein before in part recited Letters Patent is,―
The several improvements and combinations herein described, constructed and
operating substantially as set forth.
In witness whereof, I, the said William Henry Dickey, have hereunto set my
band and seal, this First day of December, in the year of our Lord One
thousand eight hundred and eighty ono.
WILLIAM HENRY DICKEY. (L.S.)