IMPROVEMENTS IN MACHINERY OR APPARATUS FOR DRYING CORN-FLOUR, STARCH, AND THE OTHER PRODUCTS IN THE MANUFACTURE OF THESE, ALSO APPLICABLE TO THE DRYING OF OTHER SUCH LIKE MATERIALS." PROVISIONAL SPECIFICATION
Year: 1880

page_text: LETTERS PATENT to John Currie, of Paisley, in the County of Renfrew, North
Britain, for an Invention of "IMPROVEMENTS IN MACHINERY OR APPARATUS
FOR DRYING CORN-FLOUR, STARCH, AND THE OTHER PRODUCTS IN THE
MANUFACTURE OF THESE, ALSO APPLICABLE TO THE DRYING OF OTHER SUCH
LIKE MATERIALS."
PROVISIONAL SPECIFICATION left by the said John Currie at the Office
of the Commissioners of Patents on the 26th August 1880.
"IMPROVE-
JOHN CURRIE, of Paisley, in the County of Renfrew, North Britain.
MENTS IN MACHINERY OR APPARATUS FOR DRYING CORN-FLOUR, STARCH, AND
THE OTHER PRODUCTS IN THE MANUFACTURE OF THESE, ALSO APPLICABLE TO
THE DRYING OF OTHER SUCH LIKE MATERIALS."
This said Invention has reference to an improved arrangement and combination
of the parts of machinery and apparatus (susceptible of considerable modification to
suit the different materials) for the drying of the ground finely prepared or
deposited damp farina or flour of Indian corn, or other grain, or of ground potatoes,
or other roots of which corn flour and flour starch are made into the said fine dry
flour, ready for packing, sale, and use; and for the drying of the coarse and less
valuable residues of or separated from the former flour materials, namely, the
busks, bran, and other granular or fibrous matters, and glutinous or gelatinous
material, into a mealy state, ready for being afterwards ground or sold for the
feeding of animals, or for other purposes; also applicable for drying the bran
residues of distilleries and breweries, in like manner, into a similar loose coarse
state, ready for being ground or sold for the feeding of cattle or or other useful
purposes, which improvements will be much superior in cleanliness and saving of
waste in heat and flour, besides being more bealthy for the men employed, as also
safety against risk by fire, than has been the case by the modes and means
heretofore employed for drying these materials.
The nature and novelty of this Invention consist all as follows:-In erecting
within a special or self-contained close square walled drying house a revolving
central vertical shaft with a number of large horizontal perforated or wire cloth
disc-like revolving drying trays or screens with shallow rims to keep in the

page_text: material in a thin layer while being dried. Each screen is secured on the shaft
over the other, at a sufficient distance apart to allow of a set of horizontal steam
heating drying pipes being placed between them, one set under the wire-cloth
bottom of each tray or screen.
Each drying screen would have the wire-cloth, or openings, or meshes of uniform
size, but very much wider in the top ones, gradually getting less towards the
lowest ones, which would be very fine when treating the flour material, to allow
the whole to pass through it on to the very lowest one, which would have no holes
and be in the form of a flat smooth disc with curved stationary blades, or other
equivalent, to deliver the dried finished flour or material quite off of it, through a
recess in one side at the bottom of the drying chamber into a spout, or bags, or
other receptacles for receiving it there, quite outside or below the drying house;
but the lower screens would be coarser for treating the coarser residues of bran
an gelatinous material than for the flour material just described.
Radial or
curvilineal stationary toothed scrapers would be fitted to or under each set of pipes
over each screen, with the teeth working down on to or near the wire cloth; and
the upper rakes or scrapers would preferably be coarser than those of the lower
screens, which have finer meshes or interstices in the wire-cloth bottoms, to stir or
break-up the material, and assist its falling through the meshes of the screen;
and the said materials to be dried would be fed by elevators, or otherwise, on to
the upper screens and fall gradually from one to the other through the whole set of
screens until it was delivered in a dry state at the bottom, as stated, in the form of
flour, or of the rougher granular material in the case of treating the residues.
One arrangement suitable for drying the said corn flour, or flour starch, farina,
or their residues, would preferably have the drying chamber fire-proof, about
twenty feet square, and with the slow revolving shaft working in footstep bush
bearings below and journal bearings at top, and be driven at top or bottom by
suitable bevil or spur gearing, or it might be screw, or band and pulleys at a slow
speeds, as from one to sixty feet of the outer part of the screens per minute, these
being about eighteen feet in diameter, and ten or so in number, about fifteen inches
apart, or over each other, made with plain radial flat web arms on top to secure
the wire cloth upon, all flat or disc-like on the upper horizontal surface, with
sufficiently strong vertical feathers below along the arms to the eyes, secured on
the vertical shaft to give sufficient strength to carry their screen and material on
it, with a shallow (two or three inch) vertical rim projecting up at the outer edge
above the wire cloth to keep the material from getting off of this while drying.
The whole height of the close drying chamber would thus be about eighteen to
twenty feet, closed in on top by the upper revolving tray, into which the material
would be fed by elevators or conducting screw trough, or otherwise, at the rate it
could be dried.
The drying steam pipes, which might be about four inches in diameter, would be
arranged horizontally and parallelly in sets of about nine on each side of the central
shaft, all joined at the opposite ends by a cross end pipe, with a short flange
branch to each, these cross pipes carrying the whole set by having their end
flanges jointed to branches on four vertical column pipes at the corners of the
drying chamber, into which heating steam would be led at' any convenient part,
and blown off at the columns at the opposite corners or sides, and the condensed
steam or water could be drawn off from the lower end of the same columns, and
the steam used might be the exhaust steam from the motive-power steam engine
which was used to grind the Indian-corn or other material being treated, and also
the driving gearing of the revolving shaft and drying screens. A sufficiently small
regulated current of dry air would be admitted near the bottom of the drying
chamber, and lowest set of pipes, to carry the heat from these up to and through
the open wire screens above themi in succession to the top, and so dry the material
as it was agitated in them, and was falling down from one screen to the other
through the hot air between the pipes, all so as to be thoroughly dried to a flour or
powder by the time it reached the bottom plain delivery platform disc before

page_text: stated. If found necessary, as when drying very damp material, a separate pipe or
flue could be provided at the top corners of the drying chamber, below the upper
screen, provided with a regulating damper to draw off any desired amount of the
moist hot air or vapour arising off the material in the lower screens, and not allow
all this to pass through the upper ones when too damp to take up more moisture.
For cleaning the farina or other loose material off the top surfaces of the drying
steam pipes, which may rest thereon while falling through between them from the
one revolving screen to the other, brushes, or loose cloth dusters, or other equivalent
cleaners, would be suitably secured on the underside of each revolving screen to
brush the upper surfaces of the set of pipes immediately below them; or otherwise,
reciprocating brushes or scrapers might be mounted on frames over each set of
pipes, and reciprocated to and fro by a connecting rod and crank, or cam action, or
other equivalent taken from the central shaft, or another shaft driven from it for
the purpose.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Currie in the Great Seal Patent Office on the 18th February
1881.
"IMPROVE-
JOHN CURRIE, of Paisley, in the County of Renfrew, North-Britain.
MENTS IN MACHINERY OR APPARATUS FOR DRYING CORN-FLOUR, STARCH, AND
THE OTHER PRODUCTS IN THE MANUFACTURE OF THESE, ALSO APPLICABLE TO
THE DRYING OF OTHER SUCH LIKE MATERIALS."
My said Invention has reference to an improved arrangement and combination
of the parts of machinery and apparatus to be employed in the drying of the.
ground finely prepared or deposited damp farina or flour of Indian corn or other
grain, or of ground potatoes or other roots of which corn flour and flour starch are
made, and for the drying of the coarse and less valuable residues of the former
flour materials, such as the husks, bran, and other granular or fibrous matters, and
glutinous or gelatinous material, into a dry granular or mealy state, ready for being
ground or prepared as feeding stuffs for animals or for other purposes. The improved
apparatus is also applicable for drying the bran residues of distilleries and breweries
into a similar loose coarse state, ready for being ground and sold as food for cattle
or for other useful purposes.
And in order that my said Invention and the manner; of performing the same
may be properly understood, I have hereunto appended for that purpose a Sheet
of explanatory Drawings, to be hereinafter referred to, representing a modification
of my improved apparatus to be employed in drying corn-flour, starch, or other
similar materials, or the residual husks or bran, of the manufacture of such
substances.
Figure 1 of these Drawings is a vertical section, and Figure 2 is a sectional plan
taken as at the lines 1 - -
-1 in Figure 1, of a modification of my improved apparatus
as designed or adapted for treating the damp or moist coarse residues of corn-flour
and delivering it in a dry state to be prepared for animal food.
Referring to these Drawings the improved apparatus, which is erected or fitted
within a special or self-contained close square walled or boarded drying house A
fitted with close doors A¹ consists of a revolving central vertical shaft B, which is
preferably made hollow, as shown, to combine strength and lightness. This shaft
is cast or formed with a series of strong flanges B₁, to each of which is secured a
large horizontal circular framing composed of radial and transverse bars or ribs C
carrying a perforated or wire cloth disc-like revolving drying tray, sieve, or
screen C, with a shallow rim c to keep in the material in a thin layer while being
dried. The frames C with the screens C are secured on the shaft B over each
other at a sufficient distance apart to allow of a set of transversely arranged hori-
zontal steam heating and drying pipes D being placed between them, one set under
each tray or screen C¹.
Each drying screen C¹ is made with the wire cloth or openings or meshes of
uniform size, but the upper series are very wide in the mesh, as shown in the
vertical section, Figure 1, while the meshes of the screens beneath are gradually
made smaller in descending order, the lowest being very fine, particularly when the
apparatus is designed for treating the flour material; but the lower screens are
made somewhat coarser in the mesh when the apparatus is used for treating the
coarser residues of bran and gelatinous material than for the flour material. Radial
or curvilineal stationary toothed scrapers or rakes E are fitted to or under each set
of pipes over each screen C, C³, with the teeth working down on to or near the
wire cloth C, and the upper rakes or scrapers are preferably coarser than those
used for the lower screens (which have finer meshes or interstices in the wire
cloth bottoms), to stir or break up the material and assist its falling through the

page_text: meshes of the screen.
Instead of the rakes E toothed rollers or barrels, as
shown over one of the screens, may be used, and these rollers are suspended by
straps or bands from the steam pipes D above passing round the spindles of the
rollers. The screens C, C¹, are kept up to the rakes or rollers E by small rollers e,
on which the lower edge of the rim of each screen bears, these rollers e being carried
by short supporting brackets. The materials to be dried may be fed by elevators
or otherwise on to the upper screens C, C¹; but in the arrangement shown, in
which the apparatus and drying chamber are fitted between two floors F, F¹, of
a building, the flooring F immediately over the drying chamber A is cut away,
and a metal grating or iron rods or wires G, set an inch or more apart, are
laid across the opening thus formed to rest on the supporting joists F2 of the
flooring, and the material falls gradually through this grating G and from
one screen C, C, to the other through the whole set of screens until it is
delivered in a dry stato at the bottom in the form of flour, or of the rougher
granular material in the case of treating the residue. The revolving shaft B
works in footstep bush bearings B2 below, and is guided in journal bearings
at the top.
It may be driven either at the top or bottom by suitable
bevil, spur, or screw gearing, or by bands and pulleys at a slow speed, as
from one to sixty feet per minute of the outer part of the screens C, C', these being
made preferably about eighteen feet in diameter, and ten, or more or less, in
number, as may be found necessary for the kind of material to be broken and dried.
The drying steam pipes D are arranged horizontally and in a parallel manner in
sets of nine or thereabouts on each side of the central shaft B, and are all jointed
at the opposite ends by cross end pipes D¹ with a short flange branch to cach;
these cross pipes D¹ carrying the whole set by having their end flanges jointed to
branches on four vertical column pipes D², which support them at the corners of
the drying chamber; and the pipes D are further supported at the middle by strong
brackets fixed to the framing of the chamber A. Into these pipes D, D1, D2,
steam is led by an inlet pipe D³ jointed to one of the columns D², and passing
through the whole series is blown off at the column at the opposite corner or side,
the condensed steam or water being drawn off from the end of the same column
through a discharge branch D* fitted with a cock d. The steam used may be the
exhaust from the motive power steam engine which is used to drive the machinery
employed to grind the Indian-corn or other material being treated, and which also
operates the driving gearing of the revolving shaft B, and drying screens C, C'.
When the heavier coarse residues of the corn flour manufacture are being treated
in the improved apparatus, a small regulated current of dry air may be admitted
near the bottom of the drying chamber A and lowest set of pipes D, to carry the
heat from these up to and through the open wire screens above them in succession
to the top, and so dry the material as it is agitated on them, and is falling down
from one screen to the other through the hot air between the pipes, all so as to be
thoroughly dried to a flour or powder by the time it reaches the bottom. For the
purpose of removing the dried pulverulent material which falls to the bottom of
the chamber A, revolving screws I are provided which draw out or remove the
material from the chamber A, as it falls into the bottom part of large corrugations J,
partly formed by wooden blocks J' on the flooring, and metal plates J¹ covering
them, which are wave like in cross section. Immediately beneath the upper
curves of these plates J" steam heated pipes K are introduced for heating and
completely drying the material on the plates J", and the pipes K. may be connected
by a cross-pipe K' at one end to the heating pipes D, D¹, D². In some cases the
lowest screen C¹ is made without holes or perforations in the form of a flat smooth
disc, with curved stationary blades to catch and deliver the dried finished flour or
material quite off it, through a recess in one side at the bottom of the drying
chamber into a spout or bags, or other receptacles, placed there for receiving it quite
outside or below the drying house.
If found necessary, as when drying very damp material, a separate pipe or flue
could be provided at the top corners of the drying chamber, below the upper screen

page_text: provided with a regulating damper to drain off any desired amount of the moist
air or vapour arising from the material in the lower screens, and not allow the
moisture to pass through the upper screens.
For the purpose of cleaning off the farina or other loose material which may rest
on the top surfaces of the drying steam pipes D while falling through between
them from the one revolving screen to the other, brushes or loose cloth dusters
or other cleaners may be used and secured on the under side of each revolving
screen, to brush the upper surfaces of the set of pipes immediately below them.
Or reciprocating brushes or scrapers might be mounted on frames over each set
of pipes, and reciprocated to and fro by a connecting rod and crank or cam action,
or other equivalent, taken from the central shaft or another shaft driven from
it for the purpose.
The improved apparatus is susceptible of modification as regards the meshes
of the screens, and otherwise to adapt it for use in treating or drying corn-flour,
and other similar finely divided materials instead of the coarser residues for which
the apparatus shown is designed.
Having thus particularly described my said Invention, and the manner of
performing the same, I desire to explain that I do not restrict myself to the
precise details herein described or delineated, but what I consider to be novel and
original, and therefore claim as the Invention secured to me by the hereinbefore
in part recited Letters Patent is, -
First. The general construction, arrangement, and combination of the parts of
apparatus to be employed in drying corn flour, starch, and other similar materials,
in which the material is agitated, broken, and made to pass through a series of
horizontal sieves or screens C, C', fitted to a revolving shaft B within a heating and
drying chamber A heated by steam pipes D, D', D2, substantially as. and for the
purposes herein described in reference to the accompanying Drawings.
Second. In apparatus employed for drying corn-flour, starch, and other similar
material, the construction, arrangement, and use of a series of horizontal revolving
screens or sieves through which the material passes within a drying chamber
heated by steam pipes, substantially as herein described in reference to the
accompanying Drawings.
In witness whereof, I, the said John Currie, have hereunto set my hand and
seal, this Seventeenth day of February, in the year of our Lord One
thousand eight hundred and eighty one.
Witness,
WALLACE FAIRWEATHER, C.E.,
of W. R. M. Thomson & Co.,
Patent Agents,
Glasgow.
JOHN CURRIE. (L.S.)