IMPROVEMENTS IN GRAIN POLISHING MACHINERY
Year: 1877

page_text: LETTERS PATENT to Carl Pieper, of Dresden, Saxony, for the Invention of
“IMPROVEMENTS IN GRAIN POLISHING MACHINERY." A communication from
Emil Menz. of Connewitz, Saxony.
Sealed the 29th September 1877, and dated the 3rd Apr 1877.
Sealed the 29th September 1877, and dated the 3rd Apru 18770
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office of
the Commissioners of Patents on the 3rd April 1877.
"IMPROVEMENTS IN GRAIN POLISHING
CARL PIEPER, of Dresden, Saxony.
MACHINERY." A communication from Emil Menz, of Connewitz, Saxony.
The machine forming the object of my Invention receives the grains through an
opening in the top, leads then by the centrifugal power between conical surfaces
covered with emery or similar composition, where they are polished and cleaned, as
one of the conical disks has a fixed position, while the other makes 200 revolutions
per minute. These disks being arranged in couples above each other, and having a
pitch of about 30 degrees, the grains will ascend in a spiral line to the outer circum-
ference of the disks, and fall down to pass between the polishing surfaces of the
next couple of disks, and so on till they arrive at the bottom of the machine. All
separated particles, as dust, germs, and points, are exposed to a constant exhaust
current of air, while the grains drop from one couple of polishing disks to the next
couple, which draft is produced by an exhausting machine sucking air through two
cylinders of perforated sheet iron, one fixed inside the machine, the other outside.
By this arrangement the exhausting machine forces always fresh air through the
cylindres, which, following the direction of the centrifugal power, drives all particles
of dust, etc., through the perforations of the outer sheet-iron cylinder, and the
perfectly cleaned grains finally fall out at the bottom of the machine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Carl Pieper in the Great Seal Patent Office on the 2nd October
1877.
CARL PIEPER, of Dresden, Saxony. "IMPROVEMENTS IN GRAIN POLISHING
MACHINERY." A communication from Emil Menz, of Connewitz, Saxony.
The machine represented by the Drawing in a vertical section, Fig. 1, and in a
horizontal section, Fig. 2, rests with its four legs b, b, b, b, on the beams a, a. These
legs or posts carry a flat ring of cast iron, in which four uprights are fixed, carrying
the top plate of the machine and the conical grinding surfaces, as it will be described
hereafter. A wooden ring of triangular section forms an air-tight joint between the
bottom ring and the sheet-iron jacket c of the machine, which also fits tightly to
the top plate above. On a cross piece between the beams a, a, a lifting mechanism d
is arranged, carrying the step bearing e of the vertical shaft f, held above in the
bearing g. The vertical shaft f is provided with the rings h connected to the inner
perforated cylinder i, and provided outside with the conical disks, having their
upper side covered with emery, or a composition of emery. This composition is
obtained by mixing emery (or similar substances, as pulverised flint, glass, etc.)
with chalk and soluble glass in different proportions, according to the quality of the
materials; it is then brought upon the conical surfaces, exposed to a pressure, and a
higher or lower degree of heat. Above these conical disks k, turning with the shaft f,
and making with it about 200 revolutions per minute, other disks are arranged in
a fixed position, having their under side covered with emery, and hanging over the
lower conical surfaces; these disks and form the cleaning parts of the machine.
On one side of the apparatus is placed an exhausting machine m, sucking air through
the inner sheet-iron cylinder i, being provided with rectangular perforations, the air
passing between the disks k and 1, and through the perforations (likewise of rectan-
gular section) of the outer cylinder n. It is of the greatest importance that the air
in this manner passes from inside to outside; in the opposite direction the current
of air would act against the centrifugal power, and both would be very much reduced.
Motion is imparted to the machine by the horizontal shaft o by means of the pulley
p and the level wheels q and r. The pulleyj transfers its motion to the pulley t of
the exhausting machine.
The grains to be cleansed fall through the hopper u (Fig. 2) on the revolving
disk of the upper story are thrown by the action of the centrifugal power between
the emery surfaces of the disks and , where they ascend (while they are rubbed
against the emery surfaces) in a spiral line to the outer circumference, whereafter
they drop into the second story to run through in the same way till they arrive at
the bottom, where they are thrown into the outlet w by the blade v. On their
whole way through the successive compartments the grains are exposed to the
action of the current of air, so that all separated particles of dust, germs, and points 4
are at once driven through the holes of the outer cylinder n, while the grains
always receive fresh air entoring through the perforations of it. The arrangement
of the machine also offers the advantage at the inner cylinder need not be sur-
ronded by a dust chamber, and can work free, so that all parts may easily be
got at.
Having thus described and ascertained the nature of my said Invention, and the
manner of carrying it out into practical effect, I would observe what I consider to be
novel and original and therefore claim as my Invention is,-
4
1. The application of surfaces arranged under an angle of 30 or more or less
degrees, and provided with an emery composition, for the purpose of cleaning and 5
polishing grains, while a strong curront of air imunediately takes away all separated
particles of dust, germs, and points.
2. The method of preparing the emery surfaces, as specified.
3. The disposition of the exhausting machine a, being insulated from the menhine

page_text: so that the current of air may be strengthened or weakened without any alteration
of the velocity of the main shaft f, b, in such a way that the air moves from inside
to outside, following the centrifugal power, and is not working against it.
In witness whereof, I, the said Carl Pieper, have hereunto set my hand and
seal, this Second day of October, in the year of our Lord One thousand
eight hundred and seventy-seven.
CARL PIEPER. (L.S.)