Apparatus for Roasting Comеe.
Year: 1897

page_text: Date of Application, 2nd Nov., 1897-Accepted, 29th Jan., 1898
Apparatus for Roasting Comеe.
We, JOHN R. OKELL, of 2504, N. 11th Street, and OTTO JULIUS PETERSEN, of
3816, Powelton Avenue, both in the City of Philadelphia, in the County of Phila-
delphia, State of Pennsylvania, U.S.A., Gentlemen, 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 :—
This invention relates to improvements in apparatus for roasting coffee; the inven-
tion having reference particularly to that class of coffee roasters which are adapted to
roast coffee by agitating the same in a revolving drum or chamber heated by a,suit-
able furnace having a combustion chamber immediately adjoining the roasting drum
of the roaster, the roasting drum being of novel construction and having interiorly
arranged agitators or lifters for carrying the coffee up and causing it to fall in a
shower through the center of the roasting drum, and it consists, first: In a coffee
roaster, the combination of a furnace having a combustion chamber immediately
adjoining the roasting drum of said roaster, a cylindrical, revoluble roasting drum
having a mouth opening directly into the interior of the drum and communicating
directly with the interior of the combustion chamber of the furnace, said drum being
very shallow in depth but of a relatively large diameter, lifting agitators arranged
within the drum for agitating the coffee, the coffee while being agitated being
subjected to the direct action of heat and flames from the furnace. It consists,
second: In the combination of parts including a suitable casing approximately closed
to the atmosphere, a revoluble drum mounted therein and having discharge openings
preferably in its periphery for discharging the coffee, when desired, levers for cover-
ing said discharge openings, means for actuating said levers, and means for supplying
heat to the interior of said drum into direct contact with the coffee. It consists,
third: Of novelly constructed and arranged lifting and deflecting means arranged
within the drum for carrying the coffee up to a considerable height and allowing it
to fall in a shower through the center of the drum, and it consists of certain other
novel constructions, combinations and arrangements of parts as will be hereinafter
described and claimed.
In the drawings
Figure 1 is a central vertical transverse view of my improved coffee roaster.
Figure 2 is a side elevation of the same, some of the parts being shown in section.
Figure 3 is a central vertical sectional view of a device constructed in accordance
with my invention showing another manner of discharging the coffee from the drum.
Figure 4 is a side elevation of the roasting drum showing the improved means for
operating the discharging means.
Figure 5 is a vertical central sectional view of a portion of the drum showing
another way of discharging the coffee, and
Figure 6 is a detail side elevation of a portion of said drumn showing the above
improved form.
A in the drawings represents a suitable frame-work, B a casing mounted thereon,
Ca revolving drum and E a heating furnace.
The frame A is preferably formed of supporting columns a a connected at their
upper ends by cross bars a¹ a¹. Within the frame-work A is constructed the casing B

page_text: which is entirely closed to the atmosphere, and is adapted to completely surround the
revolving drum and is provided with lower converging sides bb leading to a suit-
able discharge as at 61. The revolving drum C is constructed of suitable metal and
the diameter of the drum is preferably greater than the length of the druin. Secured
to each end of the drum are annular bearing rings c c bolted or otherwise secured to
the said drum. These bearing rings are adapted to rest upon suitable rollers or
wheels a² a pivotally mounted upon the frame. A. These rollers are preferably
flanged and as shown in the drawings are two in number upon each side of the frame
for supporting the respective rings c c.. It will be seen that the drum is free to revolve
upon said rollers.
In order to actuate the drum, any suitable connecting operating
ineans may be employed but we preferably use as shown in the drawings a bevel gear c¹
secured to one end of the drum which meshes with a bevel pinion csecured upon a
-revolving shaft c³. The shaft is mounted upon the frame A by a suitable bearing
as 3 and is connected with any suitable means for giving it motion. The drum C is
provided upon one side with a central opening as c for the admission of heat from a
suitable heat supply and from this point passes outwardly to spread the heat through
the entire drum, in contact with the shower of falling coffee, and upon its other side
with a central opening through which the coffee to be roasted may be admitted
to said drum. In order to do this in a proper manner and to regulate the discharge
of the coffee in the said drum, we preferably provide a hopper F provided with
a discharge pipe f leading to the mouth of the opening c³. The hopper F may be
provided with a slide or valve f¹ at its lower end for regulating the discharge of the
coffee from the same. In order to test the coffee we provide the pipe f with a suit-
able opening as f² in which a testing implement may be inserted at any time to
withdraw some of the grains of coffee and inspect its condition. The heat supplied to
the drum through the opening ct at one end is generated in a furnace E of suitable size.
This furnace is preferably constructed with an extra large combustion chamber and
without a chimney and in such a way that all gases as well as every product of
combustion will be thoroughly consumed causing a very great heat. This heat is
adapted to be delivered into the drum through the pipe or chute e leading to the
mouth of the opening c in the drum C, directly in contact with the shower of falling
coffee, the heat being confined by reason of the fact that the outer casing is entirely
closed to the atmosphere. We preferably construct this chute or pipe e with a hopper-
shaped lower side as e¹, the converging sides e³ ³ of which terminate so as to form the
snall openings e² as illustrated. We have found that in revolving the druin that grains
of coffee are sometimes thrown through the opening c and we provide this hopper with
its converging sides in the chute e in order to prevent the coffee thus thrown out of
the cylinder, from going into the furnace and being burnt or destroyed. What falls
into the hopper will pass through the opening e² and may be collected in any
suitable vessel or receptacle.
A very important feature of our drum is the means for discharging the coffee when
desired from suitable points in the periphery. In providing for this feature we
preferably construct the drum with suitable apertures or openings c c at intervals in
the periphery of the drum. In order to control the discharge of the coffee through
these apertures, we provide sliding gates or doors c c movably secured upon the
exterior of the drum. These doors c c slide in grooves or ways as cc formed on
the periphery of the drum. In order to operate the doors we provide levers G G
pivotally mounted upon each end of the drums at g g, the outer ends of said levers
being connected to the doors by links g¹ gl. The inner end of these levers G G are
secured to a ring g² which engages an annular groove in the internally threaded
ring g. The ring g' is provided with a hand operating ring g whereby it may be
rotated to move the ring g back and forth upon the thread of the extension g
according as it is desired to open or close the doors upon the periphery of the drum.
It will be seen that by these means we are enabled to open the discharge apertures
while the drum is in motion at any time and that all the apertures are adapted to
be opened at the same time and that they can be closed again in the same manner.
The intermediate portion of the periphery of the druin between the discharge.

page_text: openings is preferably formed of wire screen or similar material preferably provided
with perforations so that as the coffee is agitated in the drum the chaff and similar
foreign substance may drop through between said screen into the casing B. In the
bottom of the casing B we preferably cover the discharge opening by placing a
tray be in said opening to collect the chaff and other foreign substance. Sometimes
this chaff catches on fire in extreme heat which is not desirable and in order to pre-
vent this possibility we contemplate filling the tray 60 with water. Of course when
it is desired to discharge coffee from the periphery it is necessary to remove the tray
from over the discharge opening in the casing B. When the tray is removed and
the coffee is being discharged from the drum, a damper m provided in the pipe or
chute e is operated to close said chute thus preventing the heat and flame from
entering the drum.
The interior surface of the drum is preferably provided with a series of lifting or
carrying agitators preferably arranged parallel and extending lengthwise of the drum.
These serve to carry the coffee up a considerable distance upon the revolving drum
and are continually discharging their contents back into the lower part of said
drum, through the center of the same. In order to more thoroughly mix the coffee
and spread it more effectively through the heat in said drum we also provide spirally
arranged deflectors h h secured across the inner edges of the deflecting agitators H H.
We also arrange still a third series of deflectors h¹ h¹ which are spirally disposed and
secured to the inner edges of the spiral agitators h h but extending in an opposite
direction to the same. It will be apparent from this construction that we are
enabled to keep a constant shower of coffee thrown in different directions passing
through the strong heat maintained in the drum and in this manner we are enabled
to thoroughly roast the coffee. The deflectors also serve to polish the coffee and
knock off the chaff or scaly portions that may be left upon the same. The casing B
is provided upon one side with an outlet leading to a flue B'. This flue is preferably
made smaller compared with the size of the chute for the entrance of the hot air so
that the hot air will remain in the casing and drum as long as possible before it can
escape through the flue B¹, the casing B and consequently the drum C being
otherwise substantially closed to the atmosphere.
As shown in Figures 3 and 4 we may, in place of the sliding doors above described,
use hinged doors, as J placed at suitable points upon the periphery of the drum.
These doors are provided at one end with cranks j' which cranks are adapted to be
operatively connected with the hand revolving ring j2 by suitable links j³ ³. It will
be seen that by this mechanism it is only necessary to turn the hand ring in order to
draw the links inward which through the agency of the cranks oscillate the doors on
the periphery of the drum so as to discharge the contents thereof.
In Figures 5 and 6 we have shown another manner by which the coffee may be
discharged. In this form the levers K K are pivotally mounted on the end of the
frame, their inner ends being pivotally connected to a ring k engaging an annular
groove upon a hand wheel. This hand wheel k¹ is provided with internal threads
upon a cylindrical extension secured to the end of the drum.
levers K carry the doors or levers thereof and are adapted to close openings in the
end of the drum at the periphery thereof. It will be seen that by revolving the hand
wheel these doors may be opened or closed as desired.
The outer ends of the
After considerable experimenting we have found the construction of the roaster and
furnace shown in the accompanying drawings to be the most practical and efficient
for readily and thoroughly roasting large quantities of coffee; the main feature of
the construction and arrangement being the employment of a cylindrical revolving
roasting drum having a flaring mouth opening directly into the interior of the drum
and communicating directly with the interior of the combustion chamber of the
furnace, and having said drum approximately very shallow in depth but of a
relatively large diameter and constructing and arranging the agitators or lifters
within the drum so as to carry the coffee up to a considerable height and allow it to
fall in a shower through the center of the drum and subject it, while falling, to the
action of intense heat and flames direct from the furnace. In actual practice, the

page_text: combustion chamber of the furnace is relatively only about nine inches from the heat
entrance to the revolving drum, and the drum is only about twenty-four inches in
depth while in diameter it is relatively about six feet.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
1. In a coffee roaster, the combination of a furnace having a combustion chamber
immediately adjoining the roasting drum of said roaster, a cylindrical, revoluble
roasting drum having a flaring mouth opening directly into the interior of the drum
and communicating directly with the interior of the combustion chamber of the
furnace, said drum being approximately very shallow in depth but of a relatively
large diameter, lifting agitators or pockets arranged within the drum for carrying the
coffee up to a considerable height and allowing it to fall in a shower through the
center of the drum and through the flames and heat direct from the furnace,
substantially as described.
2. In a coffee roaster, the combination of a furnace having a combustion chamber
immediately adjoining the roasting drum of said roaster, a cylindrical, revoluble drum
having a mouth opening directly into the interior of the drum and communicating
with the interior of the combustion chamber of the furnace, said drum being
approximately very shallow in depth but of a relatively large diameter, lifting
agitators or pockets arranged around the inner periphery of the drum for carrying
the coffee up and causing it to fall in a shower through the center of the drum and
through the flames and intense heat direct from the furnace, and a casing enclosing
the drum which casing is provided with a stack, substantially as described.
3. In a coffee roaster, the combination of a furnace having a combustion chamber
of unusually large size immediately adjoining the roasting drum of said roaster, a
cylindrical, revoluble roasting drum having a flaring mouth opening directly into the
interior of the drum and communicating directly with the interior of the combustion
chamber of the furnace, said drum being approximately very shallow in depth but of
a relatively large diameter, lifting agitators or pockets arranged around the inner
periphery of the drum for carrying the coffee up and causing it to fall in a shower
through the center of the drum and through the flames and intense heat direct from
the furnace, additional agitators for deflecting the coffee as it falls from the lifting
agitators or pockets, and a casing enclosing the drum, which casing is provided with
a stack, and a damper or gate located between the furnace and the drum for cutting
off communication between the same, substantially as described.
4. In a coffee roaster, the combination of a furnace having a combustion chamber
of unusually large size, a revoluble roasting drum closed to the atmosphere but open
at one end for the admission of flames and heat directly from the furnace, and
agitating lifters or pockets arranged around the inner periphery of the drum for
carrying the coffee up, a series of agitators extending entirely across the lifting
agitators in a spiral direction combining with said latter agitators to cause the coffee
to fall in a shower through the center of the drum, and a casing enclosing the drum
which is provided with a stack, the construction and arrangement being such that
all flame and heat passes directly from the furnace into the drum and through the
falling coffee before passing out the stack in the casing, substantially as described.
5. In a coffee roaster, the combination of a furnace, having a combustion chamber
of unusually large size, a revoluble roasting drum closed to the atmosphere but open
at one end for the admission of flames and heat directly from the furnace, a series of
agitating lifters or pockets arranged around the inner periphery of the drum for
carrying the coffee up, a second series of agitators extending entirely across the
lifting agitators in a spiral direction and a third series of agitators extending entirely
across the lifting agitators or pockets but in an opposite direction to the second
series, the spirally arranged agitators combining with the lifting agitators to cause
the coffee to fall in a shower through the center of the drum, and a casing enclosing

page_text: the drum which is provided with a stack, the construction and arrangement being
such that all the flame and heat passes directly from the furnace into the drum and
through the falling coffee before passing out at the stack in the casing, substantially
as described.
6. In a coffee roaster, the combination of a revoluble drum, means for admitting
hot air to one end of the said drum, means for charging the said drum with coffee at
the other end, discharge openings in the periphery of said drum and doors for
controlling the said discharge openings, levers mounted upon one end of the drum
for opening said doors, and means for actuating the said levers, substantially as
described.
7. In a coffee roaster, the combination of a revoluble drum, means for revolving
the same, means for heating the drum, agitators for lifting the coffee arranged
around the inner side of the periphery of the drum and forming pockets, a second
series of agitators extending spirally across the first set of lifting agitators for
deflecting the coffee as it falls, substantially as described.
8. In a coffee roaster, the combination of a revoluble drum, means for heating the
same, a series of agitators on the inner periphery of the drum, a second series of
agitators spirally arranged across the first set of agitators, and a third set of agitators
spirally arranged across the second set of agitators, but in an opposite direction to
said second set, substantially as described.
9. In a coffee roaster, the combination of a revoluble drum provided with annular
bearing rings, a casing for entirely enclosing the drum from the atmosphere and
provided with a stack, rollers exterior to said casing for supporting the said bearing
rings and gearing secured to the end of said drum, means for revolving the same,
lifting agitators or pockets arranged around the inner periphery of the drum, a
second series of agitators spirally arranged across the lifting agitators or pockets,
and a third series of agitators spirally arranged across the second series of agitators
but in an opposite direction to the said second series, a furnace arranged at one end
of the drum for throwing flames and heat directly into the interior of the drum, and
a damper interposed between the flames and the drum for regulating the supply
of heat to the drum, the construction and arrangement being such that the heat
and flames pass directly from the furnace into the drum through the falling coffee
and out at the stack in the casing, substantially as described.
10. In a coffee roaster, the combination of a revoluble drum provided with a
discharge opening in its periphery, doors for closing said openings, means for
operating the doors while the drum is revolving, a casing entirely enclosing the
drum from the atmosphere, provided with a stack and formed with lower converging
sides leading to a suitable discharge opening, a tray in said casing arranged over
said discharge opening and a furnace adjoining the roasting drum and opening
directly into the interior of the same, substantially as described.
11. In a coffee roaster, the combination of a revoluble drum, means for supplying
coffee to the same, a furnace for supplying heat to said drum, and a connecting
heat pipe or chute having diverging sides leading to a discharge opening, whereby
any grains of coffee thrown from the drum may be collected and prevented from
entering the furnace, substantially as described.
12. In a coffee roaster, the combination of a furnace having a combustion chamber
immediately adjoining the roasting drum of said roaster, a cylindrical, revoluble
roasting drum having a mouth opening directly into the interior of the drum and
communicating directly with the interior of the combustion chamber of the furnace,
said drum being approximately very shallow in depth but of a relatively large
diameter, and coffee agitators arranged within the drum, substantially as described.
NEWTON & SON,
Agents for the Applicants.