Improvements in Apparatus for Drying Coffee and other Articles.
Year: 1893

page_text: Date of Application, 19th Aug., 1893
Complete Specification Left, 19th May, 1894-Accepted, 23rd June, 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Drying Coffee and other Articles.
I RICHARD PENROSE HOCKING of Mayaguez, Porto Rico Engineer, do hereby
declare the nature of this invention to be as follows:-
My invention relates to improvements in apparatus for drying coffee, and it has
for its object to provide an apparatus especially designed for drying the fruit of the
coffee tree after the red shell has been removed from the berry, the apparatus being.
so constructed that the berry is subjected to constantly recurring currents of heated
air, which after impinging upon the berry find a speedy exit from the apparatus.
A further object of the invention is to so construct the drying chamber of the
apparatus that as the said chamber is revolved the berries contained therein will
constantly change position, thereby presenting every portion of their surface to the
drying agent.
The essential feature of the invention consists in the construction of the drying
cylinder, which consists of a pair of concentric walls with an intermediate space
which forms the drying chamber. This space may be divided by partitions into
compartments or deflectors may be arranged within it so as to compel the articles
dried to travel in a circuitous path. The cylinder is mounted upon a shaft and
supported by a spider which is provided with rings secured to the arms of the
spider. A head is bolted to each set of end rings and a wire cloth forming the
outer and the inner walls of the cylinder is secured at its ends upon said rings and
if necessary to the heads also.
The wire cloth is held in place and stiffened by longitudinal bars which extend
from one edge to the other at desired intervals apart. The inner wall of the
drying chamber is preferably continuous but the outer wall is usually provided with
two doors, one adapted to cover the opening through which the material to be dried
is entered, while the other closes the exit. These doors extend from end to end of
the cylinder and are preferably placed opposite one another.
The cylinder shaft is journaled in the ends of a casing practically of the same
shape as the cylinder, except at its lower end, where a neck extends vertically
downward below the cylinder. Between the outer wall of the cylinder and the
inner wall of the circular portion of the casing, there is a space so that the cylinder'
can revolve freely within the casing while permitting a circulation of air around the
cylinder.
The casing is provided at the top with a pair of doors placed opposite one
another with a space between them and adapted jointly to cover a feed opening,
the space between the doors serving as an exit opening for the heated air or heating
agent after it has performed its work. To enable the amount of air escaping to be
regulated, the exit opening may be closed by a gate or valve pivoted or hinged to
one of the doors of the casing.
This
The neck of the casing is provided at opposite sides with doors to permit
whatever material may be delivered to the neck section of the casing to escape at
its sides. It has a floor which is pitched from the centre downward in direction of
its edges, the pitch being at opposite sides, or in direction of the doors.
flooring has a longitudinal' opening, preferably at its centre, normally covered by a
pitched hood supported by the flooring and extending from end to end of the
casing, the sides of the hood or those portions facing the doors in the casing being
open, so that the heating agent may pass up through the flooring opening into the

page_text: hood and then out into the casing, the heating agent thence passing through the
cylinder and entering the drying compartment with greatest force at the bottom and
sides of the cylinder.
In this manner the currents of heated air will be constantly passing through the
drying chamber over and around the material contained therein; and after acting
upon the material the heated air will pass out through the casing to make room for
other currents, thereby subjecting the material to be dried to substantially the same
temperature at all times.
As the cylinder is revolved, the berries or other material is constantly shifted and
different surfaces constantly presented to the heating agent.
A furnace or other heat-generating device may be employed in connection with
the casing and the cylinder. Preferably, however, as hot air is employed as the
heating medium, the furnace consists of a fire box communicating by a passage with
a tube sheet arranged at one end of the casing and carrying one end of a series of
pipes, and a second tube sheet at the opposite end of the casing by which the
opposite ends of the tubes are carried, the pipes being in communication with an
offtake flue or flues.
The pipes are contained within a compartment beneath the neck of the casing,
the flue sheets constituting the ends of the compartment, while the sides are
constructed of metal plates, or are otherwise formed. Cold air passes in at the
bottom of the compartment, which is furnished with valves, and is admitted to the.
upper portion of the compartment through a grated partition whose openings are
controlled by suitable slides.
In this manner cold air constantly enters the furnace and passes up around the
tubes and becomes heated and then passes through the opening in the flooring of
the casing and is directed to the cylinder.
It is obvious that the tubes will be much hotter at their ends at which the
products of combustion enter than at their ends where the said products find an
exit; and in order to prevent one portion of the cylinder receiving hotter currents
of air than the other, a horizontal arch is constructed over the upper row of pipes
within the furnace below the flooring of the casing, and this arch extends to a point
above the longitudinal centre of the furnace.
In order to reduce the pipes at their ends receiving the products of combustion
to prevent said products entering the pipes in too great a volume, reducing
thimbles are placed in the flue sheet and into the receiving ends of the tubes.
These thimbles are flanged upon their outer faces, and therefore the flue sheet is
reinforced around the openings through which the products of combustion are passed
into the tubes.
In the operation of the drier, the material to be dried is placed within the
drying chamber by opening one of the doors in the outer wall of the cylinder when
it is opposite the doors of the casing, and it is discharged from the cylinder by
opening one of the doors when it is over the hood in the bottom of the casing so
that the material strikes upon the inclined surface of the hood and slides from
thence to the inclined surface of the floor by which it will be conducted to the
openings in the neck.
The heated air may be passed into the cylinder at other points than at the
bottom; as for example, the cylinder shaft may be hollow and contain perforations
and serve as a conductor for the heated air, but in this event the current of air could
only pass through the upper portion of the cylinder.
Dated this 10th f August 1002
R. P. HOCKING,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.

page_text: Improvements in Apparatus for Drying Coffee and other Artic
I RICHARD PENROSE HOCKING, Engineer, of Mayaguez, Porto Rico, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
My invention relates to improvements in apparatus for drying coffee and it has
for its object to provide an apparatus especially designed for drying the fruit of
the coffee tree after the red shell has been removed from the berry, the apparatus
being so constructed that the berry is subjected to constantly recurring currents
of heated air, which after impinging upon the berry find a speedy exit from the
A further object of
apparatus, the exit of the air being under complete control.
the invention is to so construct the drying chamber of the apparatus that as the
said chamber is revolved the berries contained therein will constantly change
position, thereby presenting every portion of their surface to the drying agent.
The invention consists in the novel construction and combination of the several
parts, as will be hereinafter fully set forth and pointed out in the claims.
Reference is to be had to the accompanying drawings forming a part of this
Specification, in which similar figures and letters of reference indicate corre-
sponding parts in all the views.
Figure is a side elevation of the apparatus, a portion of the casing being
broken away so as to disclose the drying cylinder, and a portion of the furnace
wall being also broken away to show the interior ;
Figure 2 is an outer face view of a portion of the flue sheet of the drying
furnace;
Figure 3 is a vertical section taken through the flue sheet, and practically on
the line 3-3 of Figure 2; and
Figure 4 is a vertical transverse section taken through the entire apparatus,
practically upon the line 4-4 of Figure 1.
The main feature of the invention consists in the construction of the drying
cylinder A. The said cylinder may be of any diameter required and of any
desired length, and it consists of two concentric walls, an inner wall 10 and an
outer one 11. The space between these two walls may be made as wide as
necessary, and the said space constitutes a drying chamber B. Preferably this
drying chamber is without partitions, being continuous, but if in practice it is
found desirable, one or more partitions may be placed within the drying chamber,
dividing it into one or more compartments; or the partitions, may extend for a
portion only of the length of the cylinder, thereby forming deflecting plates to
compel the articles dried to travel in a circuitous path.
The detail construction of the cylinder A, is practically as follows:
At each end arms 12, are projected from a hub 13, forming thereby a spider,
and the arms are adapted to support rings or bands 14, secured thereto in any
suitable or approved manner; a head 15, is securely bolted to each set of end
rings, and a wire cloth forming the outer and the inner walls of the cylinder is
secured at its ends upon said rings; and if necessary to the heads also.
The wire cloth is held in place, and stiffened, by a series of longitudinal strips or
bars 16, which extend from one edge to the other at desired intervals apart. The
inner wall 10 of the drying chamber B of the cylinder, is preferably unbroken ;
that is to say, it is continuous, but the outer wall 11, is usually provided with two
doors designated respectively as 17 and 18, both of which may be hinged, or both
of them may be sliding, or as illustrated in the drawings one may be a hinged
door and the other may be a sliding door, the hinged door being adapted to cover

page_text: the opening through which the material to be dried is entered, while the sliding
door is located over the opening at which the material is to make its exit. These
doors extend from end to end of the cylinder, and are preferably placed opposite
one another in order to balance the cylinder when it is revolved.
The cylinder is secured upon a shaft 19, journaled in the ends of a casing D.
The casing is of practically the same shape as the cylinder, except at its lower
end, where a neck D' is formed extending vertically downward below the
cylinder; and between the outer wall of the cylinder and the inner wall of the
circular portion of the casing D a space 20, is provided, enabling the cylinder to
revolve freely within the casing and at the same time permitting a circulation of
air around the cylinder.
The casing is usually provided at the top with two doors 21 and 22. These
doors are ordinarily hinged, and are adapted to be carried upward and outward.
The doors 21 and 22, while they are located opposite one another and are adapted
jointly to cover a feed opening in the casing, do not approach one another closely,
a space 23 intervening between them, as shown best in Figure 4. This space is
adapted as an exit opening for the heated air or heating agent after it has
performed its work upon the article to be dried; and in order that the amount of
air escaping may be regulated to suit various conditions and various materials to
be dried, the opening 23 may be entirely or partially closed by a gate 24, serving
in the nature of a valve, as shown in Figure 4, said gate being pivoted or hinged
to one of the doors of the casing.
The neck D of the casing is provided at opposite sides with a door, 25, which
doors are adapted to fold upward and outward, as shown in dotted lines; and
permit whatever material may be delivered to the neck section of the casing to
escape at its sides. The neck of the casing is provided with a floor 26, which is
pitched from the centre downward in direction of its edges, the pitch being at
opposite sides, or in direction of the doors 25. This flooring is provided with a
longitudinal opening 27, preferably located at its centre, as shown in Figure 4 ;
and the opening is normally covered by a pitched hood 28, erected upon the
flooring 26 and extending from end to end of the casing, the sides of the hood or
those portions facing the doors 25 in the casing being open so that the heating
agent, whatever it may be, as shown by the arrows in Figure 4, is adapted to pass
up through the flooring opening 27 into the hood and then out into the casing
through the side openings in the hood, and from the lower portion of the casing
the beating agent will pass through the cylinder, entering the drying compartment
with greatest force at the bottom and sides of the cylinder; after the drying
agent has performed its function it will pass off through the exit opening 23 at the
top of the casing.
In this manner the currents of heated air, for example, will be constantly
passing through the drying chamber over and around the material contained
therein; and after acting upon the material the heated air will pass out through
the casing to make room for other currents, thereby subjecting the material to be
dried to substantially the same temperature at all times.
As the cylinder is adapted to be revolved, the berries or other material
contained in the drying chamber of the cylinder, will be constantly shifted, and
therefore different surfaces will be constantly presented to the heating agent to be
properly acted upon by it.
:
The cylinder may be revolved in any suitable or approved manner; in the
drawings the mechanism employed for that purpose consists of a worm wheel 30,
which is mounted upon one end of the shaft 19; the said worm wheel being in
mesh with a worm 31, upon a drive shaft 32, which may be provided with a driving
pulley 33, when the shaft is to be driven by a motor;
or a crank may be
connected with the shaft, or the equivalent thereof, to enable it to be revolved by
hand.
Any approved form of furnace, or other heat-generating device may be
employed in connection with the casing and the cylinder. Preferably, however, hot

page_text: air is employed as the heating medium, and the furnace illustrated in the drawings-
is utilized for heating the air. This furnace consists of a fire box 34, which is.
connected by a passage 35 with a tube sheet 36, adapted to receive one end of a
series of pipes 37. The tube sheet 36, is generally placed below one end of the
casing, and a second tube sheet 38 is located at the opposite end of the casing,
which receives the opposite ends of the tubes; the pipes passing through the-
tube sheet 38, being in communication with an off-take flue or flues 39, as shown in
Figure 1. The tubes 37 may be supported intermediate of their ends by suitable-
rods or bars 40.
The tubes 37, are located within a compartment 41 beneath the neck of the-
casing, the flue sheets constituting the ends of the compartment, while the sides 42,.
are constructed of metal plates, or are otherwise formed, as shown in Figure 4.
Cold air is admitted to the lower portion of the compartment through the medium
of slides 43, and is admitted to the upper portion in which the pipes 37, are located,.
through the medium of a grated partition 44, whose openings are controlled by
suitable slides 45, operated ordinarily from the exterior of the furnace.
Thus it will be observed that the cold air will constantly enter the furnace, and
will pass up around the tubes and become heated, and will then pass through the-
opening 27 in the flooring of the casing and be directed to the cylinder.
It is obvious that the tubes will be much hotter at the ends at which the-
products of combustion enter than at the ends where the said products find an exit ;.
and in order to prevent one portion of the cylinder receiving hotter currents of air
than the other, a horizontal arch 46, is constructed over the upper row of pipes.
within the furnace below the flooring 26 of the casing, this arch extending to a
point above the longitudinal centre of the furnace.
The tubes are made large in order that as large an amount as possible of heat--
radiating surface may be obtained; and in order to reduce the pipes at their ends
receiving the products of combustion to prevent said products entering the pipes in,
too great a volume, reducing thimbles 47 are placed in the flue sheet 36, as shown.
in Figures 2 and 3, and in the receiving ends of the tubes. These thimbles are
flanged upon their outer faces, and therefore the flue sheet is reinforced around the
openings through which the products of combustion are passed into the tubes.
In the operation of the drier, the material to be dried is placed within the drying
chamber B by opening the door 17, for example, of the cylinder when it is opposite.
the doors 21 and 22 of the casing, the latter doors being open; and the material is
discharged from the cylinder by opening the cylinder door 18, when that door is.
over the hood 28 in the bottom of the casing, and the lower doors 25 in the casing.
neck being open, the material discharged from the cylinder will strike upon the
inclined surface of the hood 28 and will slide from thence to the inclined surface
of the floor, by which it will be conducted to the openings disclosed by opening the
doors 25.
I desire it to be understood that various details of the invention may be changed
and equivalents may be employed without materially affecting the spirit of the
invention. For example the heated air may be passed into the cylinder at other
points than at the bottom; and the cylinder shaft may be hollow and contain
perforations and serve as a conductor for the heated air, but in this event the
current of air could only pass through the upper portion of the cylinder.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is,
1. In a drier for coffee and other articles, a cylinder provided with a drying
chamber having an inner and an outer wall of perforated or reticulated material, as.
and for the purpose specified.
2. In a drier for coffee or other articles, a cylinder provided with a continuous.
drying chamber having an inner and an outer wall of perforated or reticulated.
material, substantially as and for the purpose set forth.

page_text: 3. In a drier for coffee or other articles, a cylinder provided with closed ends and
a peripheral surface of perforated or reticulated material, and having a second
cylinder of smaller diameter and corresponding peripheral surface secured within it,
a space intervening the two cylinders, which space constitutes a drying chamber,
substantially as and for the purpose set forth.
4. In a drier for coffee and other articles, a drying chamber having its opposing
side walls constructed of perforated or reticulated material, and means, sub-
stantially as shown and described, for passing hot air through the perforated walls
of the cylinder, as and for the purpose specified.
5. In a drier for coffee or other articles, a drying chamber of cylindrical shape,
having its ends closed and its sides constructed of perforated or reticulated
material, and means, substantially as shown and described, for passing currents of
heated air through the chamber, as and for the purpose specified.
6. In a drier for coffee and other articles, a cylindrical, revoluble drying chamber
having closed ends, and sides of a perforated or reticulated material, doors located
in one wall of the chamber, and means, substantially as shown and described, for
passing currents of heated air through the chamber, and carrying the air off from
the chamber, as and for the purpose set forth.
7. In a drier for coffee and other articles, a casing provided with a valved
opening, and a cylinder held to revolve within the casing, said cylinder being
provided with an annular drying chamber, the opposing side walls of which are
of perforated or reticulated material, and means, substantially as shown and
described, for passing currents of heated air through the drying chamber, the air
escaping through the valved opening in the casing, as and for the purpose set
forth.
8. In a drier for coffee and other articles, a casing provided with outlet doors
and inlet doors, and a valve located at one of the inlet doors, a cylinder held to
revolve within the casing, provided with an annular drying chamber closed at its
ends and having its side walls perforated or reticulated, which chamber is provided
with an inlet and a discharge door, and means for producing and conducting heated
air through the drying chamber, which air escapes at the valve in the casing,
substantially as and for the purpose set forth.
9. In a drier for coffee and other articles, the combination, with a cylindrical
revoluble drying chamber having its side walls constructed of perforated or
reticulated material, a casing encircling the cylinder provided with an outlet, and
means substantially as shown and described for charging and discharging the drying
chamber, of a furnace adapted for heating air, and a communication between the
furnace and the interior of the casing below the drying chamber, whereby the
heated air passes through said chamber from the bottom to the top and out
through the outlet opening in the casing, substantially as and for the purpose
Bet forth.
Dated this 10th day of May 1904
R. P. HOCKING,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.