IMPROVED MEANS FOR DRYING SUBSTANCES IMPREGNATED WITH MOISTURE
Year: 1870

page_text: LETTERS PATENT to Thomas Meredith Hopkins, of. Worcester, in
the County of Worcester, and of Southwark Street, in the County
of Surrey, for the Invention of "IMPROVED MEANS FOR DRYING
SUBSTANCES IMPREGNATED WITH MOISTURE.”
PROVISIONAL SPECIFICATION left by the said Thomas Meredith
Hopkins at the Office of the Commissioners of Patents, with his
Petition, on the 20th July 1870..
I, THOMAS MEREDITH HOPKINS, of Worcester, in the County of
Worcester, and of Southwark Street, in the County of Surrey, do hereby
declare the nature of the said Invention for "IMPROVED MEANS. FOR DRYING
SUBSTANCES IMPRegnated with MOISTURE," to be as follows:-
In the drying of various substances containing moisture; such as:
hops, grain, malt, and also some building materials, such as bricks in
the green or unburnt state, it has been customary to force heated air
through the layers by mechanical appliances to carry off the moisture;
and in doing this the heat has acted upon them in an injurious manner
by reason of the outside being too rapidly dried, and thereby preventing

page_text: the moisture escaping from the inside. Now by my Invention I draw
the moisture from the substance by means of fans in the uptake or
chimney, or in passages leading thereto, which fans may be worked by
steam or other power or by hand. The fans are, however, preferably
to be worked by the products of combustion passing through a tube
or tubes leading from a furnace. By this means the steam or other
vapour thrown off from the substances or material is carried away by
suction.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Thomas Meredith Hopkins in the Great Seal Patent
Office on the 20th January 1871.
TO ALL TO WHOM THESE PRESENTS SHALL. COME, I, THOMAS
MEREDITH HOPKINS, of Worcester, in the County of Worcester, and
of Southwark Street, in the County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of July, in the year of
our Lord One thousand eight hundred and seventy, in the thirty-fourth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said Thomas Meredith Hopkins, Her special licence
that I, the said Thomas Meredith Hopkins, my executors, administrators,
and assigns, or such others as I, the said Thomas Meredith Hopkins,
my executors, administrators, and 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
IMPROVED MEANS FOR DRYING SUBSTANCES IMPREGNATED WITH MOISTURE," upon
the condition (amongst others) that I, the said Thomas Meredith
Hopkins, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, 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
66

page_text: in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Meredith Hopkins, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
Drawings hereunto annexed, that is to say :-
In the drying of various substances containing moisture, such as
hops, grain, malt, and also some building materials, such as bricks in
the green or unburnt state, it has been customary to force heated air
through the layers by mechanical appliances to carry off the moisture,
and in doing this the heat has acted upon them in an injurious manner
by reason of the outside being too rapidly dried and thereby preventing.
the moisture escaping from the inside. Now by my Invention I draw the
moisture from the substance by means of fans in the uptake or chimney,
or in passages leading thereto, which fans may be worked by steam or
other power or by hand. The fans are, however, preferably to be worked
by the products of combustion passing through a tube or tubes leading
from a furnace. By this means the steam or other vapour thrown off
from the substances or material is carried away by suction.
In the case of drying hops or malt it is to be spread upon the
drying floor as usual, and the heat that rises through the flooring is
removed by a fan revolving in the chimney or uptake.
In Figures 1, 2, and 3 I have shown one plan of apparatus in order
that my Invention may be understood, but I do not confine myself
thereto, as the shape or the mode of action may be modified to suit
the particular purpose for which it is intended.
A, A, are the walls or exterior of, say, a hop drier; in the lower part
a grate or stove B is arranged. The heat thrown off from the fuel
ascends and passes through the meshes or interstices of the flooring Ở
above, and on which the hops to be dried are placed, thereby assist-
ing to dry them. The upper part D of the kiln is narrowed and
terminates in a neck E, in which a fan F is arranged, the rotation of
which sucks or draws the steam or moist vapour into the neck and
forces it out at the top. In Figure 2 I have shewn two fans with the
blades or vanes fixed in opposite directions; these are rotated by means
of bevil pinions G and the band pulley H, the shaft of which passes
through the side of the neck, so that the pulley can be operated from

page_text: the outside if required. The fire-grate I have shown open at the upper
part, so that the products of combustion can spread themselves about
in the space above, where they mingle with the air which enters
through the ventilator I, the opening or closing of which can be
adjusted to the greatest nicety by a sliding plate, which covers up the
openings more or less as desired. The driving of the fans by power is,
however, only necessary when the hops require to be dried quickly;
their rotation will in most cases be effected by a current of air which
passes up the pipe J, the lower part of which is bell-mouthed to receive
the air from the ash-pit; this pipe passes through the fire and absorbs a
portion of the heat therefrom, which is utilized to warm the air in the
pipe, and thus by its expansion create an upward draft, the air issuing
from the outlet just under the fans to force them round, and thus cause
it to pass through, drawing off the moist air from the kiln along with it.
I do not in all cases have the grate open at the top as shown, as that
plan is only of advantage when using wood or charcoal for fuel. When
.coal or other fuel is used which throws off smoke or soot, I enclose the
grate and employ a flue to lead the products to the upper part or neck
in which the fans are situated. In other cases the flue could be
returned into the ash-pit, and then passed through the fire in order to
cause the products of combustion to be reheated and partly consumed
before they rise to the uptake J.
The drying room is arranged in the usual manner with doors and
windows for admitting light and allowing the men to pass in and out
for depositing and removing the hops.
I do not in any way limit myself to the employment of two fans
working in the neck in the manner shown, nor to that class of fan, as
the blades or vanes may be portions of a screw blade on a central
spindle, as shown in Figures 4 and 5, or of any other kind as found
convenient.
In some cases the neck can be reduced in size by a concave plate
fitted in its upper end, as shown in Figures 6, 7, and 8, and then I
propose to employ a double blade or two half blades a, b, placed at right
angles to each other on a traverse bar; one of these a when turned
in one direction lies with its edge across the opening, while the other ba
stands up above the top and acts as a cowl head to be deflected by the
wind and shield the opening against down draughts and the entrance of
rain. One end of the spindle is, square on the outside and can be fitted

page_text: with a lever and rod for turning it, so that the blade end on can be
raised up through an opening, the other at the same time being brought
down to cover the aperture entirely and thus retain the heat within the
drying room.
I have in the foregoing description referred to drying hops only, but
of course grain or any other substance or material can be operated upon
in a similar manner, whether it be placed upon the floor of the drying
room, or arranged upon stands, shells, or other contrivances.
I do not in all cases employ a stove to produce heat, as in drying
bricks or other plastic substances it is not necessary; the body of air
which passes through the ventilator will be sucked up through the floor-
and carry the moisture from them as it reaches the fan or fans, when it
would be expelled through the top.
I have only spoken of one pipe J as being used for operating upon
the fans, but two or more of them can be applied if thought advisable.
I sometimes arrange the grate in the pipe or uptake, and I suck the
smoke and gases away from it by a fan placed in a bent portion of the
pipe. The products of combustion are afterwards caused to pass through
the fire to be consumed before they are.led away to the chimney. This
portion of my Invention is available for other than hop or grain drying
apparatus.
The same apparatus can be employed for cooling liquids, as by it the
steam or heat can be abstracted.
The Drawings annexed to this Specification are, as before stated, only
given to explain more fully how my Invention can be carried into effect,
therefore they must not be taken as showing my exact manner of
accomplishing the object I have in view; but what I consider novel and
desire to claim is, drying or extracting moisture from hops, grain, plastic
bodies, or other substances; and cooling liquids, by suction instead of by
force.
In witness whereof, I, the said Thomas Meredith Hopkins, have
hereunto set my hand and seal, this Nineteenth day of January
One thousand sight hundred and somente ona
T. M. HOPKINS. (L.S.)