IMPROVEMENTS IN DOVING GRATE AND OFFED SUBSTANCES
Year: 1855

page_text: LETTERS PATENT to John Weems, of Johnstone, in the County of Ren-
frew, North Britain, Tinsmith, for the Invention of "IMPROVEMENTS IN
DOVING GRATE AND OFFED SUBSTANCES
"
Sealed the 28th December 1855, and dated the 29th June 1855.
PROVISIONAL SPECIFICATION left by the said John Weems at the
Office of the Commissioners of Patents, with his Petition, on the 29th
June 1855.
I, JOHN WEEMS, of Johnstone, in the County of Renfrew, North Britain,
Tinsmith, do hereby declare the nature of my said Invention for "IMPROVE-
MENTS IN DRYING GRAIN AND OTHER SUBSTANCES" to be as follows, that
is to say:
This Invention relates to the application and use of heated air for effecting
the dessication or drying of grain, malt, and other substances in a more rapid
and superior manner than has hitherto been accomplished. The grain or malt
to be dried according to this Invention is laid out in a thick or deep layer upon
a horizontal perforated plate or floor, and the heated air used in drying is blown
or forced through the perforations in such floor, and thience into and through
the layer of grain upon the floor: The chamber containing the drying floor is
preferred to be of a duplex cylindro-conoidal form, but it may be variously
shaped. In the large inverted cone portion of the chamber beneath the drying

page_text: floor is a collection of vertical tubes, or narrow air passages of other form.
These tubes or air passages' open at their lower ends into a wide air duct, lead-
ing from a blast fan, pump, or other air forcer beneath, so that on working the
fan or air forcer an air current is directed up through the tubes, and thence
into the lower part of the drying chamber, which may be suitably coned or
inclined internally to direct the air through the grain layer on the perforated
floor. The air tubes or passages are themselves inclosed in a vertical heating
case, into the lower end of which steam is blown in by a bottom side pipe, pro-
vision being made for the escape of the water of condensation, as well as for
the passage off of the uncondensed vapor at the upper end. In the case of
high-pressure steam engines being used as the actuating power of the fan or
air forcer, the waste steam after being usefully employed in this way, is passed
into the air tube case, so as to surround and heat the tubes externally, and
thus heat the minute air currents passing through the tubes in readiness for
acting upon the grain. A communicating air duct passes down from the
conical cover of the heating chamber to the fan or air forcer, so that the heated
air passed through the grain. layer may be exhausted or withdrawn from the
upper part of the drying chamber and repassed by the fan action through the
heating tubes and through the grain. This endless current of air may be kept
up for a longer or shorter time, as may be desired, until the air has attained
the desired temperature, when the duct from the top of the chamber may be
wholly or partially closed, provision being always made, however, for the escape
of the air and vapours from the upper part of the chamber to the extent
required: The drying chamber; may be so arranged as to be capable of con-
tinuous action without losing time in recharging with undried-grain. This.is.
done by forming the chamber in such manner that a freshly charged perforated
floor may be passed into the chamber just as the one covered with dried grain-
is removed.
=
A little steam may be passed through the grain with the heated air, for the
purpose of tempering the grain, and purifying it when musty or mouldy,
and for otherwise acting on whatever substances may be operated on. The
heated air may be forced either upwards. or downwards in drying grain
according to this system, & the existing kilns heated by furnaces may be
employed in it. It will be obvious to practical men that exhaustion may
be employed in forming a heated air current instead of direct forcing:

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
...by the said John. Weems in the Great Seal Patent Office on the 29th
-December: 1855.
*.*
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
WEEMS, of Johnstone, in the County of Renfrew, North Britain, Tinsmith,
send greeting.
win r
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of June, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Jolin Weems, Her special license that I, the said John Weems,
my executors, administrators, and assigns, or such others as I, the said John
Weems; my executors, administrators, or assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands; and Isle of Man, an Invention for "IMPROVEMENTS IN DRYING GRAIN
AND OTHER SUBSTANCES," upon the condition (amongst others) that I, the said
John Weems, by an instrument writing under hand and seal, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed in
the Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Weems, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following.
statement in writing, reference being had to the accompanying Drawings,
and to the letters and figures marked thereon, that is to say :-
My said Invention relates to the application and use of heated air for
effecting the desiccation or drying of grain, malt, and other substances in a more
rapid and superior manner than has hitherto been accomplished. The grain
or malt to be dried according to this Invention is laid out in a thick or deep
layer upon a horizontal perforated plate or floor, and the heated air used in
drying is blown or forced through the perforations in such floor, and thence
into and through the layer of grain upon the floor. According to one modifi-
cation, the chamber containing the drying floor is preferred to be of a duplex
cylindro-conoidal form, but it may be variously shaped. In the large inverted

page_text: cone portion of the chamber beneath the drying floor is a collection of vertical
tubes, or narrow air passages of other form. These tubes or air passages open
at their lower ends into a wide air duct leading from a blast fan, pump, or
other air forcer beneath, so that on working the fan or air forcer an air current
is directed up through the tubes, and thence into the lower part of the drying
chamber, which may be suitably coned or inclined internally to direct the air
through the grain layer on the perforated floor. The air tubes or passages are
themselves inclosed in a vertical heating case, into the lower end of which
steam is blown in by a bottom side pipe, provision being made for the escape
of the water of condensation, as well as for the passage off of the uncondensed
vapour at the upper end. In the case of high-pressure steam engines being
used as the actuating power of the fan or air forcer, the waste steam after
being usefully employed in this way is passed into the air tube case, so as to
surround and heat the tubes externally, and thus heat the minute air currents
passing through the tubes in readiness for acting upon the grain. A commu-
nicating air duct passes down from the conical cover of the heating chamber
to the fan or air forcer, so that the heated air passed through the grain layer
may be exhausted or withdrawn from the upper part of the drying chamber,
and repassed by the fan action through the heating tubes and through the
grain. This endless current of air may be kept up for a longer or shorter time,
as may be desired, until the air has attained the desired temperature when the
duct from the top of the chamber may be wholly or partially closed, provision
being always made, however, for the escape of the air and vapours from the
upper part of the chamber to the extent required. The drying chamber may
be so arranged as to be capable of continuous action without losing time in
recharging with undried grain. This is done by forming the chamber in such
manner that a freshly charged perforated floor may be passed into the chamber-
just as the one covered with dried grain is removed. A little steam may be
passed through the grain with the heated air, for the purpose of tempering the
grain, and purifying it when musty or mouldy, and for otherwise acting on
whatever substances may be operated on. The heated air may be forced either
upwards or downwards in drying grain according to the system, and the
existing kilns heated by furnaces may be employed in it. It will be obvious
to practical men that exhaustion may be employed in forming a heated air
current instead of direct forcing.
And in order that my said Invention may be properly understood, I shall
proceed particularly to describe one mode of working it out in practice, as
applied to a grain-drying kiln of a large size, such kiln being constructed in

page_text: other respects like those at present in use; and I have hereunto attached a
Sheet of Drawings explanatory of the said mode of working out my Invention,
to which Drawings I shall refer in the course of my description.
:
And in the first place I may state, that Fig. 1 on the said Sheet of
Drawings is a vertical section of a building, constructed as a grain store and
grain-drying kiln, and fitted with my improved drying apparatus; and Fig. 2
is an irregular horizontal section of the same building, shewing the air-heating
apparatus in plan. In this instance two air-heating vessels. A are employed,
each consisting of an iron cylinder, through which a number of small air tubes
B are passed. These tubes communicate at one end with a chamber. C, formed
in this instance of brickwork, and erected against the wall D. of the building.
The chambers C each communicate with the discharge aperture of an air-
blowing fan E, which forces in a strong current of air, causing the same to
pass through the tubes B of the air-heating vessels A.. The air-heating agent
employed is steam, which may be the exhaust steam of a high-pressure or non-
condensing steam engine, as, for example, of that by which the fans. E are
driven. This steam enters each of the vessels A by a pipe F, by preference at
the discharge end of the air tubes, and, enveloping these tubes, communicates
its heat to the air passing through them. The steam or its condensed product
passes off from the vessels A by the pipes G, and each vessel is fitted with a
pipe H, communicating with safety pressure & vacuum valves I. The air
currents heated in their passage through the vessels A next find their way:
through the passages J to a long channel or chamber K, extending under the
entire length of the kiln floor L, or nearly so. The air-heating apparatus is in
this instance placed on the ground floor of the building, the kiln floor L being
that immediately above it. This kiln floor is supported upon the cast-iron
columns M, which are connected by the longitudinal beams N. Upon these
beams are placed a series of smaller transverse beams or joists O, and upon
these last are laid a series of longitudinal bars or rods P. Finally, upon the
bars P is laid a sheet of wire cloth Q, the whole forming a permeable flooring,
upon which the grain R to be dried is spread out in an even layer, the heated
air rising from below through the permeable floor, and through the layer of
grain upon it. The heated air has access to the whole of the under side of the
permeable kiln floor through openings in the sides of the channel K, and
through apertures S in the transverse partition walls. The egress apertures
of the channel K. may of course be made adjustable, so that the air currents
may be regulated, or so that they may be confined to any particular part of the
kiln. The air currents and the moisture which they carry off from the grain

page_text: pass off up the ducts T to the roof of the building, and as these ducts pass
through the various storing floors U, doors may be formed in them for passing
the grain down' through them to the kiln below.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried
into effect, I may observe, in conclusion, that I do not confine or restrict
myself to the precise details or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from the principles or main features of my said Invention; but what
I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is,―
First, the general arrangement and construction of apparatus for drying
grain and other substances, as herein-before described.
Second, the system or mode of drying grain and other substances by passing
currents of air through them, such currents of air being first heated by passing
over or in contact with steami-heated surfaces, as herein-before described:-
In witness whereof, I, the said John Weems, have hereunto set my
hand and seal, this Twenty-seventh day of December, One thousand
eight hundred and fifty-five.
JOHN WEEMS. L.S.)