Improvements in Apparatus for Roasting Coffee.
Year: 1890

page_text: Date of Application, 9th Jan., 1890
Complete Specification Left, 10th Nov., 1890-Accepted, 13th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Roasting Coffee.
I, ABRAHAM MARTIN of 177, Aston Lane, Birmingham, in the County of Warwick,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to improvements in apparatus for roasting coffee; and it
consists of a revolving cylinder. traversed by longitudinal tubes which serve primarily
as heating surfaces, being heated internally by atmospheric gas-burners supplied from
a central chamber at one end of the cylinder, and also as stirrers, to assist in keeping
the coffee in agitation during the revolution of the cylinder, so as to ensure fresh
surfaces being continually brought into contact with the heating tubes, and a uniform
roasting of the whole mass of coffee berries. By this means, the mass of coffee is
heated internally at several points at once, instead of being heated externally at one
point, as usual, whereby the time of roasting is considerably curtailed. The cylinder
may also be provided with internal pallets, to assist in maintaining a continual
agitation of the berries.
The cylinder is provided at one end with a double wall of which the inner one bas
openings, to permit the escape of the vapors distilled off, the openings being near the
circumference and in such number that one at least will always be above the level of
the mass of berries within the cylinder, so that a free escape for the said vapors will
always be afforded. The said openings are protected by wire gauze, or perforated
sheet metal, to prevent the escape of the berries, and, being constantly exposed to the
frictional contact of the mass of berries in motion within the cylinder, the perforations
are kept constantly free from clogging by the pellicles detached from the berries in
the roasting operation.
The space between the double end communicates with the tubular journal of the
cylinder through which the vapors are conveyed away to a condenser for the separation
of their constituents by fractional condensation, those of the constituents which con-
tribute to the aroma and palatable flavor of the coffee being returned in the condensed
form to the roasted coffee. The outlet is provided with a two-way cock or valve
whereby the necessary pressure is maintained in the cylinder and the first vapors
distilled off from the coffee, which contain a large proportion of those constituents
which it is not desirable to retain, are allowed to escape, those subsequently generated
being conveyed to the condenser. The cylinder is provided with one or more mouths,
for charging and discharging, and may have internal inclines leading thereto, to
facilitate discharging.
The cylinder is provided with a sampling cup at one end, which, at each revolution.
catches one or two beans and delivers them through a door on to an outside ledge,
said door being automatically operated when it reaches the highest point in the
revolution.
حيم
1900

page_text: Improvements in Apparatus for Roasting Coffee.
I, ABRAHAM MARTIN, of 177, Aston Lane, Birmingham, in the County of Warwick,
Engineer, 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 roasting coffee which I have
illustrated in the accompanying drawings, forming part of this Specification, wherein
Figure 1 is a central longitudinal section of the apparatus; Figure 2 is a cross-section;
and Figure an end elevation of the apparatus; Figure 4 is a detail view of the
sampling device. The same letters of reference denote like parts in all the figures.
The apparatus consists of a cylinder A mounted to revolve on a horizontal shaft B
and traversed from end to end by flues (which serve primarily as heating surfaces
and also as stirrers to assist in keeping the coffee in agitation during the revolution of
the cylinder so as to ensure fresh surfaces being continually brought into contact with
the said flues and a uniform roasting of the whole mass of coffee berries. The
cylinder may also be provided with internal pallets with a like object. Each flue Cis
traversed longitudinally by a perforated pipe D. communicating with a chamber E
common to all the pipes, to which a mixture of gas and air is supplied through the
adjacent hollow journal of the shaft B and which is burnt at the perforations of the
pipes D within the flues C. By this means the cylinder is heated internally, instead of
externally as usual, whereby a more uniform distribution of the heat throughout the
mass of coffee is ensured and the time required for roasting is considerably shortened.
The cylinder is provided at the other end with a double head enclosing a space F with
which communicates the other hollow gudgeon of the shaft B by perforations b. In
the double heads corresponding pairs of openings are formed in which are fitted
cylindrical gauze or perforated metal strainers G projecting across the chamber F into
the cylinder, the outer ends of the strainers being covers closing the apertures in the
outer head. By this means the free escape of the vapors distilled off from the coffee
is continuously permitted, the strainers G being near the circumference of the cylinder
and in such number that one at least will always be above the mass of berries in the
cylinder. The strainers are readily removable if they should become clogged by
pellicles detached from the berries during the roasting operation. The escaping vapors
are conveyed to a condenser for separation of their constituents by fractional con-
densation with the view to the restoration, in the condensed form, to the roasted
coffee of those constituents which contribute to the aroma and the palatable flavor of
the coffee.
In order to permit a certain pressure to be maintained in the cylinder and allow of
the free escape of the first vapors distilled off, which contain
of those constituents which it is not desirable to retain, a two-way cock, not shewn,
large proportion
may be provided between the journal and the condenser.
more mouths H for charging and discharging, closed by sliding or other doors held
The cylinder has one or
in place by bridge pieces and pressure screws and internal inclines I are provided to
conduct the coffee to the mouths in discharging. A sampling cup K.is fixed to the
end of the cylinder at which point there is an aperture in the cylinder end closed by
a cover L carried by a lever / pivoted at 1 to the end of the cylinder, a spring acting
on the tail end of the lever holding the cover in the closed position. At each revolu-
tion a few berries are caught in the cup K and delivered on to a tray M, the cover L
being automatically opened at the proper moment by a friction roller N on the end of
an arm n of the lever meeting a cam O carried by a bracket P. The cam O is
pivoted at o and fixed in operative position by a set screw and may be thrown out of
the path of the roller N when the sampling device is to be put out of action.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is;
1. A coffee roaster, consisting essentially of a horizontal revolving drum traversed
by heating flues heated internally by gas burners, substantially as specified.
2. A coffee roaster, consisting of a horizontal revolving drum traversed by internally
heated flues, as described, and provided with means, substantially as described, for
conveying away the vapors distilled from the coffee, as specified.
3. The combination, with the horizontal roasting cylinder, of the herein described
sampling device whereby a few berries are delivered at each revolution of the drum,
as specified.
4. The herein described improved coffee roasting apparatus, substantially as
specified.
Dated this 10th day of November 1890.
A. MARTIN.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.