IMPROVEMENTS IN MIDDLING PURIFYING MACHINES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Martin Benson at the Office of the
Commissioners of Patents on the 23rd April 1878. A communication from
abroad by Ambrosius Millot, of Zurich, Switzerland.
MARTIN BENSON, of No. 9, Southampton Buildings, London.
"IMPROVEMENTS
IN MIDDLING PURIFYING MACHINES." [A communication from abroad by Ambrosius
Millot, of Zurich, Switzerland.]
One of the principal novelties of my improvement is making the machine double,
or dividing it into two or more separate parts for causing the air to act on the
greatest possible surface of the material being treated, and also making the sieves
sloping through the entire machine.
The machine is composed of a suitable framework, and by preference made of
wood, about seven feet long, three feet wide, and five feet high, more or less. A
shaft passes through the body of the machine longitudinally, working in bearings
on the frame of the machine; this shaft is provided with a double aspirating fan at
its centre, thereby dividing the machine into two parts or chambers, one at each
end of the machine. Each of these chambers are provided with a series of sloping
sieves, seven or eight, more or less, to suit the work required to be done, and on
which the middlings to be treated are fed by first distributing the middlings by a
feed roll or rolls from a hopper or funnel on two or more large sieves placed on the
top of the machine, and covered with silk gauze of different fineness. Each of
these sieves can be removed independently, and are made to separate the bran from
the middlings, and separate the middlings into two or more sizes for passing to
the series of sieves before mentioned.
The series of sieves are so arranged that the middlings being treated are made to
fall from one to the other. The double fan is made to exhaust the air from the
chambers of the machine, which causes currents of external air to pass inwardly
through the series of sieves, and thereby purify the middlings. Each sieve belonging
to the series of sieves has an independent small air or condensing chamber for con-
veying the impurities from the middlings into the main air chamber, and from
thence to the fan, by which it is discharged from the machine.

page_text: The main chambers are provided with valves for regulating the intensity
of the current of air passing through the series of sieves and chambers into
the exhaust fan. There are two inside valves, one for each chamber of the
machine, for regulating the current of air through each chamber independently of
the other chamber. There are also external regulating valves between the series
of sieves and internal valves, and between the internal valves and fan for regulating
the intensity of the current of air in the several parts of the machine with which
the said valves communicate. These valves may be constructed for self-regulating,
or made to regulate by hand.
Another portion of my improvement is causing the fan to compress air in spaces
or chambers under the distributing bolter or sieve for keeping the meshes of the
sieves open.
The distributing sieves receive a shaking motion by any known suitable mechanism
worked from any convenient moving part of the machine, for causing the material
to pass from the hopper to the tail end of the machine for being properly distributed
to the series of sieves enclosed in each chamber.
The series of sieves may be covered with metal or silk gauze or perforated metal
to suit the material being treated.
The chambers of the machine opposite the ends of the series of sieves, and also
the air passages or condensing chambers are provided with openings furnished with
glass to serve as windows for inspecting the interior of the machine while in
operation.
By employing a series of incline or slopien sieves, as before described, the middlings
are separated and purified to an extent which has never been done heretofore in
machines where the current of air acts upon the mass of middlings falling from
board to board.