AN IMPROVED MACHINE FOR HULLING AND POLISHING COFFEE
Year: 1877

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "AN IMPROVED
MACHINE FOR HULLING AND POLISHING COFFEE." A communication from
abroad by José Guardiola, of Chocolá, in the Republic of Guatemala, Central
America.
Sealed the 28th March 1877, and dated the 13th February 1877.
COMPLETE SPECIFICATION filed by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 13th February 1877.
"
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent.
AN IMPROVED MACHINE FOR HULLING AND POLISHING COFFEE."
A communication from abroad by José Guardiola, of Chocolá, in the Republic of
Guatemala, Central America.
This Invention relates to an improved machine for hulling and polishing coffee,
and it consists in the arrangement in batteries of a series of mortars having internal
longitudinal ribs and a corresponding number of conical pestles having oblique
projecting ribs, the said pestles being attached to the ends of vertically sliding bars
that are raised by a rotating drum having spiral cam ribs on its periphery, and are
permitted to fall when disengaged from the said ribs.
The Invention further consists in the arrangement of valves at the bottom of the
mortars by which the coffee or other article is discharged after being hulled and
polished.
In the accompanying Drawings Figure 1 is a side clevation of the improved
hulling machine in part section. Figuro 2 is a central vertical section of one of the
mortars. Figure 3 is a transverse section of the same on line x, x, Figure 2.
Figure 4 is a detail view of one of the pestles. Figure 5 is a longitudinal section of
one of the pestles, taken on line y, y, Figure 4.
A is the frame of the machine in which mortars B are supported by the flanges a
These mortars are provided with internal longitudinal ribs b, b¹. The ribs b extend
to the discharge aperture c at the bottom of the mortar, and the ribs b' are
discontinued a short distance above the said aperture. C, C, are valves fitted to the
discharge aperture c of the mortars B and attached to a lever d that is hinged to a
stude that projects downward from the frame A. To the outer end of the levers d
Darine A1

page_text: a rod is attached that extends upward through a hole in the frame A and is
provided with an eye to which a chain his attached, having at its free end the
cross bar or handle i. By means of these handles the valves C are raised so as to
close the discharge aperture c of the mortars when a pin j is placed through the cyc
above the frame A and prevents the valve from dropping, and when this pin is
removed the downward inotion of the valve c is checked by the handle i which
strikes the frame A. Pestles D corresponding to the number of mortars are secured
to the lower ends of beans that slide in guides in the cross beams l, m, of the
frame A. The pestle D is made of cast iron or other suitable material, of inverted,
truncated, conical form, or nearly so. From its sides project a series of ribs n, n,
extending nearly from end to end and slightly curved, as shown in Figure 4.
Between every two ribs n, n, on the upper part of the pestle is another and shorter
rib o which divides the groove between the longer ribs as shown. E is a drum
secured to the shaft F which is journalled centrally in the frame A. The drum E
is provided with spiral cam ribs p which engage rollers q placed on studs that
project from sliding beams k. The drum is rotated by power taken from any
convenient motor.
The operation of the improved coffee huller is as follows:-The mortars B being
filled with coffee berries in the hull, the drum E is rotated when the beams k carrying
the pestles D are raised by the action of the cam ribs p. As the rollers a pass the
highest point of the ribs the beans k drop, carrying the pestles into the coffice
contained in the mortars B. As the pestle descends a part of the coffee berries aro
displaced in the centre of the mortar, and when the pestle is withdrawn from the
mortar the berries at the sides of the mortar fall toward its centre, and at each
successive stroke of the pestle this operation is repeated, the pestle striking deepor
into the mortar at each stroke.
The coffee is forced up through the curved grooves between the ribs of the pestle,
and it also moves in the grooves formed in the sides of the mortar. The friction
thus created divests the berries of their superfluous pellicles and polishes them.
When the operation is completed a pin is put through the beam & above the beam
when the pestle is at the highest part of its stroke. The pestle is thus prevented
from falling and the contents of the mortar may be removed by opening the valve C.
This is accomplished by removing the pin j from the cyo y and allowing the lever d
to fall the length of the chain h After the mortar is discharged the valve C may
be closed and the mortar refilled, when the pin may be withdrawn from the hole 7
and the pestle allowed to rise and fall as before. The downward motion of the
pestles is limited by a shoulder formed on the beam k, so that it cannot strike the
bottom of the mortar and crush the coffee.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as new, and desire to secure by Letters
Patent is,-
First. The mortar B provided with internal longitudinal ribs b, b', and discharge
aperture c, constructed and arranged substantially as herein shown and described.
Second. The hulling pestle D provided with ribs nando, constructed substantially
as herein shown and described.
Third, The combination of the mortar B having the discharge aperture c, the
valve C, lever D, rod f, and a suitable fastening device, substantially as herein shown
and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set my
hand and seal, this Twelfth day of February, in the year of our Lord One
thousand eight hundred and seventy-seven.