NEW OR IMPROVED PNEUMATIC MACHINES FOR DRYING CORN AND OTHER SUBSTANCES
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Edward Griffith Brewer at the
Office of the Commissioners of Patents on the 5th October 1883 communi-
cated to him from abroad by Ettore Delbecchi, of Turin, Italy
EDWARD GRIFFITH BREWER of 33, Chancery Lane in the County of Middlesex
"NEW OR IMPROVED PNEUMATIC MACHINES FOR DRYING CORN AND OTHER
SUBSTANCES (A communication to me from abroad by Ettore Delbecchi of Turin
Italy)
"
Drying machinery constructed according to this invention whatever the particular
construction or arrangement may be is based upon the application of the following
fact. A gaseous current being formed by the mixture of the products of combustion
operating or produced in no matter what sort of furnace propelled or sucked by a
fan, exhauster or blowing apparatus no matter what may be the construction
traverses one or several layers of corn or other substance to be dried by coming in
direct and immediate contact with the substances to be dried without the
intervention of a metallic or other heating surface through which the transmission
of the heat in drying apparatus or machinery has heretofore been done
Drying machinery based on this fundamental point may be constructed in
many ways but whatever may be the arrangement of the parts they comprise the
following parts.
1°. A fan or exhauster no matter what the construction may be for regulating
the movement of the air and products of combustion acting either by pressure or
by suction and necessitating the air and combustion gas to follow the course
necessary to make the drying machine work.
2°. A chamber or fireplace for the production of heat the products of combustion
which when issuing mix with the cold air in such manner that the mixture
acquires a temperature which cannot injure the substance to be dried.
3°. A drying chamber containing one or several layers of corn or other substances
intended to be traversed by the gaseous current resulting from the mixture of cold
air with the products of combustion
It is still to be remarked that whatever may be the particular arrangement
which is given to the pneumatic drying machinery constructed according to this
invention it is always necessary that the parts of which they are composed should
satisfy the following conditions which are indispensable to success.

page_text: 1. It is necessary that the fan should give a very large volume of air under a
pressure as low as possible.
2. The furnace should be constructed so as to obtain the most perfect combustion
possible of the smoke and of the principal volatile matters contained in the fuel.
This is accomplished by the more or less complete turning of the flame and by
arranging the furnace as a kind of gas retort where the coal is slowly heated
disengaging the principal volatile matters therein contained which are then burnt
in the furnace.
3. Where the layers of corn or other substances are. always held by a metal plate
or by a grating or by a trellis the interstices allow passage for the gaseous
current.
4. Drying machines made according to this invention are always provided with
one or other of the following arrangements viz appliances for continually dis-
tributing and mixing the grains of the corn so as to carry the coldest into the
position occupied by the warmest and vice versa or an arrangement for reversing
alternately the direction of the travel of the gaseous current in such manner that
the gaseous current alternately traverses the layers of wheat or other material in
two opposite directions. By either of these two arrangements the objection of the
grains which first come in contact with the gaseous current being heated successively
are avoided and those which are more distant do not receive the quantity of heat
necessary for the drying. Drying machines made according to this invention may
be either fixed or movable and mounted on a carriage.
When a fixed drying apparatus constructed according to this invention is used,
the corn is placed on a grating and is stirred during the operation of the drying
machine either by the hand or by some known arrangement of mechanical
stirrer.
According to another type of fixed drying machine the corn is placed on a
horizontal grating. It is not necessary in this case to stir it, for the drying
machine is provided with the necessary arrangements for alternately changing the
direction of the movement of the gaseous current.
In a portable drying machine the corn is supported between metallic sheets with
vertical perforated or trellis sides.
Several drying machines may be mounted on a single car and supplied by a
single furnace and by a single fan.
The fan causes a portion of the internal air to enter into the furnace to keep up
the combustion and also draws other external air to mix with the products of
combustion by afterwards forming a gaseous current, the temperature of which is
reduced so as not to be injurious to the cereals.
The gaseous current enters and passes through a distributing chamber where the
speed of the gas diminishes so as to render it easy to obtain a temperature and
even pressure in the current which comes in contact with the surface of the gratings.
The gaseous current circulates there where the layers are supported by the metallic
plates gratings or perforated sides and afterwards escapes to the atmosphere taking
with it the steam with which the grains of corn were charged.
The essential parts of these drying machines may be also arranged in a different
way to those described without departing from what forms an essential part of
the invention; for example the furnace may be located between a suction fan and
the drying chamber also the furnace may be placed first then an air suction
apparatus across the furnace and forcing it into the drying chamber which follows.
It is intended that all these variations should be comprised within the scope of this
application for patent.
In another arrangement of drying apparatus the inverse of the currents is
obtained by means of valves and by changing the direction of the rotation of
the fan.
Supposing that at first the valves are in one position, the external air drawn by
the fan enters into the furnace in one direction another part of the external air
follows in another direction and mixes with the products of combustion coming

page_text: from the furnace forming together a uniform current of the desired temperature.
This current after having traversed the heliocoidal fan enters the distribution
chamber, traverses throughout it the layer of corn and becomes mixed with the
humidity which becomes disengaged from it passes by the interstices of the grating
and thence to the chamber or collector.
When the direction of the motion of the fan is reversed and the valves are
turned so as to make them assume one position the current is interrupted and it
becomes on the contrary a current in the other direction always resulting in the
mixture of the products of combustion with the currents of cold air. The current
thus produced enters into the distributing chamber the formation of an intimate
and perfect mixture between the cold air and the products of combustion is
rendered easier by traversing a passage provided with openings by traversing
which the two gaseous products the hot and the cold break up and become mixed.
The fan draws the mixture in the chamber which now operates as collector, it
there arrives by traversing the layer of corn, to issue at a cross orifice after having
passed the fan.
It is also by acting on obturators that the direction of the gaseous current in
one arrangement is reversed or changed.
When the obturator is in one position the depression produced by the exhauster
draws the external air through or across the drying apparatus. A portion of this
air traverses the furnace another portion also enters the distributing chamber after
having passed round outside the furnace. The resulting mixture passes into
passages through the orifices left open by the respective obturators. The
manometric depression existing in the collector and in the passages which are in
communication with the latter (because the obturators have left open the orifices
they are intended to close) exhausts the gaseous mixture compelling it to traverse
the layers of cereals which are supported by the metallic plates. The alternate
opening and closing of the obturators is obtained by means of a cranked shaft to
which rotary motion is communicated by means of a crank in order to open all
the obturators which were closed and to close those which were open. By this
very simple means the gaseous current is changed; in fact the passages which first
receive the current of dry air and heat proceeding from the chamber afterwards
serve for the closing of one set of obturators and the opening of another set situate
opposite the preceding to allow passage to the air charged with steam, on the
contrary the passages which were first in communication with the collector will
after the inversion be put in communication with the distribution chamber and
will receive from it directly the hot air.
In the description of the arrangement before referred to, the drying of cereals
has been referred to, but the arrangements are applicable to no matter what other
agricultural product may be required to be treated in a similar manner.