IMPROVEMENTS IN ROASTING COFFEE, AND IN APPARATUS THEREFOR."
Year: 1880

page_text: LETTERS PATENT to Francis George Fleury and Edward Dunning Barker,
45, Bedford Row, W.C., for an Invention of "IMPROVEMENTS IN ROASTING
COFFEE, AND IN APPARATUS THEREFOR."
PROVISIONAL SPECIFICATION left by the said Francis George Fleury and
Edward Dunning Barker at the Office of the Commissioners of Patents on the
24th June 1880.
FRANCIS GEORGE FLEURY and EDWARD DUNNING BARKER, 45, Bedford Row,
W.C. 'IMPROVEMENTS IN ROASTING COFFEE, AND IN APPARATUS THEREFOR."
In order to describe more particularly the improvements under our Invention, it
may be remarked that in the process of coffee roasting, as at present in vogue; the
raw material is placed in vessels which are subjected to a considerable amount of
heat for a short period. During its roasting in these vessels, samples are obtained
in order to judge the right moment to stop off the heat, and when it is considered
expedient to stop the roasting process, the contents of the vessels are emptied into
sieves or coolers, and thence into sacks. As no attempt is made in these roasting
vessels to render them steam tight, but rather the reverse, a great loss in weight is
sustained in this process due entirley to evaporation of the water, volatile liquids,
and essential oils contained in the berries. This loss generally averages 18 to 20
pounds in the hundredweight, so that if the yield of onehundred weight of coffee
roasted in this way is 92 pounds, it is deemed rather satisfactory than otherwise.
In our improved system of roasting the raw material is enclosed in vessels
practically steam tight, and capable of withstanding a considerable pressure.
Before commencing to roast, these vessels are in addition charged with a con-
siderable volume of compressed air or other gas, and the roasting is carried on
under this superinduced pressure. When it has been found by means of the
samples taken out of the vessel that this roasting has been carried on sufficiently
far, the vessel is rapidly cooled by water or other means, and the initial pressure
with which the vessel was charged is not released until the temperature is
sufficiently low. By this process it is found that a great saving in weight is effected,
as well as preventing the escape of the essential oil which imparts to coffee its
agreeable aroma.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent_filed
by the said Francis George Fleury and Edward Dunning Barker in the Great
Seal Patent Office on the 24th December 1880.
FRANCIS GEORGE FLEURY and EDWARD DUNNING BARKER, of 45, Bedford Row,
W.C. 'IMPROVEMENTS IN ROASTING COFFEE, AND IN APPARATUS THEREFOR."
In order to make clear the nature and object of our improved process of roasting
coffee, it should be stated that in the process of coffee roasting, as at present in
vogue, the raw material is placed in vessels which are subjected to a considerable
amount of heat for a short period. During its roasting samples are obtained in
order to judge of the right moment to stop off the heat, and when it is considered
expedient to stop the roasting process, the contents of the vessel are emptied into
sieves or coolers, and from thence into sacks. As however no attempt is made in
these roasting vessels to render them steam tight, but rather the reverse, a great
loss in weight is sustained in this process due entirely to the evaporation of the
water, volatile liquids, and essential oils contained in the berries. This loss
generally averages from eighteen to twenty pounds in the hundredweight, so that
if the yield of, say, one hundred weight of coffee roasted in this way is ninety two
pounds, it is deemed rather satisfactory than otherwise.
In our improved system of roasting the raw material is enclosed in a cylinder
practically steam-tight, and capable of withstanding a considerable internal pressure.
Before commencing to roast, this vessel is in addition charged with a considerable
volume of compressed air, carbonic acid, or other innocuous gas, and the roasting is
carried on under this superinduced pressure.
To test the process of roasting we withdraw from time to time samples of the
coffee berries by means of a testing instrument, and when it is found by an
inspection of the samples that the roasting has been carried on sufficiently far, the
cylinder is rapidly cooled by water from a jet pipe, and the initial pressure with
which the cylinder was charged is not released until the temperature is sufficiently
low. By this process it is found that a great saving in the weight of the product
is effected, and the escape of the essential oil which imparts to coffee its agreeable
aroma is prevented.
In the accompanying Drawings we have shewn in several views an arrangement
of apparatus by which our improved process of roasting coffee may be efficiently
carried out.
Fig. 1 is a plan view of the apparatus complete; Fig. 2 is a longitudinal vertical
section taken in the line 1, 2, of Fig. 1; Fig. 3 is a right hand end elevation of the
apparatus, and Fig. 4 is a left land end elevation of the same.
In these Figures A is tho steam tight roasting cylinder formed of plate iron and
provided with a copper lining B. This lining is coned at one end (see Fig. 2) to
constitute a funnel connection with the hollow journal of the cylinder by which
the coffee is admitted to and discharged from the cylinder.
The lining B is provided with blades which extend the whole length of the lining,
and serve as the cylinder rotates to turn over the coffee, and expose it all.equally to
the heat applied to the cylinder.
Fig. 5 is a cross section of the cylinder and its lining, shewing also the situation
of the blades which converge towards the axis of the cylinder.
This cylinder is mounted in a skeleton framing C, it being provided at its
opposite ends with hollow journals a, a', which turn in roller bearings in the
frame C.
This frame is fitted at the middle of its length with hollow trunnions c, c', which
rest in bearings in the main frame D.
The object of thus mounting the cylinder A is to allow of its being turned either
i

page_text: end upwards for the purpose of charging it with coffee berries through the
journal a¹, and of discharging the berries when roasted through the same journal.
This journal is closed by means of a screw cap a³, which is removed for the
purpose of charging or of discharging the cylinder.
Keyed to the journal a is a spur wheel as through which rotary motion is
imparted to the cylinder. This wheel as gears into a spur wheel e keyed onto the
driving shaft E, which is provided with driving pullies for receiving a band from
any prime mover.
The shaft E has its bearings in the main frame D.
The journal a is fitted with a gland to receive a stationary tube F, which is cast
with a flange to carry a conical box f.
In this conical box is fitted a hollow plug fl, and in the plug and box are formed
lateral openings which are brought into coincidence for the purpose to be presently
explained.
Attached centrally to this plug f' is a tube ƒ³, which extends into the cylinder A,
and is closed by a conical shell f. Fitting into this shell is a conical plug f*,
which is bored to correspond with the tube f, but is formed with an internal
projection for the purpose to be presently explained. Lateral openings are made in
the shell and its plug to allow of the entrance of a sample of the berries when the
openings are brought into coincidence.
G is a test rod provided at one end with a receiver g of a cylindrical form, and
fitting like a plug the tube f. A portion of the side of this cylinder is cut away
for the purpose of engaging with the projection within the plug, and also for
bringing the cylinder into communication with the openings in the plug and the
shell 3.
The outer end of the test rod G is furnished with a handle g¹ for moving it in
and out of the tube f², and imparting to it an axial motion for the purpose of
operating the plug f³, and opening it to and closing it from connection with tho
chamber. When the receiver of the test rod is charged, it is drawn outwards, a
packing being provided in the conical box f to prevent the admission or escape of
air, and when the cylinder has entered the hollow plug f, the latter is turned by
a handle provided for the purpose to permit of the discharge of the sample through
the opening in the conical box f.
This box fis cast with hollow projections on its sides to form couplings for two
pipes H, H, which connect it with the hollow trunnions c, c', of the framic C.
In connection with these hollow projections of the box f, passages are cored out
in the box to open a communication with the pipes H, H', and the interior of the
cylinder A. The passage / leading from the pipe H enters an annular passage in
the journal a, formed by the insertion of a tube within that journal. The passage h'
communicates with a concentric annular passage in the journal a immediately
surrounding the tube ƒª.
This arrangement is provided for the admission to the cylinder of compressed air
or gas by the one pipo B, and the discharge of the same when the roasting is
completed by the other pipe H'. The compressed air or gas is forced into the
cylinder, say, at twenty pounds to the square inch (preparatory to commencing the
roasting process), by means of a force pump I, which is in connection with
the trunnion c, and a stop cock or valve is fitted to the trunnion c¹ for preventing
the escape of the air or gas while the operation is proceeding.
Situate under the cylinder A is a series of gas jets or burners K (see Fig. 4),
extending the whole length of the cylinder, the heat from which is directed onto
the cylinder as it slowly rotates, and is caused to circulate over a large portion of
its periphery by means of the hinged segment shaped shield L overlying the
cylinder.
As the roasting proceeds the compressed air or gas, which is confined in the
cylinder by a cock ², expands under the increasing heat until an internal
pressure of one hundred pounds to the square inch more or less is attained. It will
therefore be necessary to provide in the construction of the cylinder for a resistance

page_text: of a great internal pressure. When the roasting is completed, which the attendant
will determine by the tests taken, as already explained, the shield will be thrown
back to the dotted position of Fig. 4, and a water pipe M which is pierced with jet
holes will be brought to play upon the cylinder for the purpose of cooling it down
suddenly, and condensing the volatile essences contained in the cylinder, and
concentrating them in the roasted berries. This water pipo is cranked at its ends
which turn in bearings on the main framing. In order therefore to bring the pipe
into use, it is only necessary to move it over into the dotted position of Fig. 4, and
to turn on the tap m.
To prevent tho oscillation of the frame C when the apparatus is at work,
a catch c³ is provided for locking into fixed projections on the main frame D.
Having now set forth the nature of our Invention of "Improvements in Roasting
Coffee, and in Apparatus therefor," and explained the manner of carrying the same
into effect, we wish it to be understood that under the above in part recited Letters
Patent we claim,—
First. The roasting of coffee under the pressure of air or equivalent fluid, as and
for the purpose above set forth.
Secondly. The use of an air-tight rotating roasting cylinder or vessel capable
of being charged with compressed air, or its equivalent, and permitting of the with-
drawal of samples therefrom, and of its being suddenly cooled when the roasting
operation is completed, as and for the purpose above set forth.
In witness whereof, I, the said Francis George Fleury, have hereunto set my
hand and seal, the Twenty second day of December, in the year of our
Lord One thousand eight hundred and eighty.
SATA
DI PIIRY