MENTS IN THE MEANS OF AND APPARATUS FOR SEPARATING SUBSTANCES OF DIFFERENT SPECIFIC GRAVITIES
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Thomas Jonas Chubb at the
Office of the Commissioners of Patents, with his Petition, on the 5th
December 1866.
I, THOMAS JONAS CHUBB, of Brooklyn, in the State of New York, United
States of America, but now of 66, Chancery Lane, in the County of Middlesex,
Engineer, do hereby declare the nature of the said Invention for. "IMPROVE
MENTS IN THE MEANS OF AND APPARATUS FOR SEPARATING SUBSTANCES OF DIFFERENT
SPECIFIC GRAVITIES," to be as follows:-
My Invention of improvements in the means of and apparatus for
separating substances of different specific gravities is intended more par-
ticularly to apply to the separation of ores of iron and other metals from
the impurities with which they are usually found mixed. To this end the
mineral is reduced to a granular or pulverized state, if not already in the form
of sand, and separation of the valuable ore from the impurities with which it
is mechanically mixed is effected by means of an inclined perforated bed or
table, on which the particles are kept in agitation by means of puffs of air
being made to pass up through the perforations of the inclined table or bed
and through the mass of ore that lies thereon. This perforated inclined bed
or table is not only set at an inclination, but is or may be also canted a little
on one side, so that one of the lower angles of the table is lower than the
other. The table is also provided on its upper side with two or more series
of diagonal bars, which act as stops or guides to the downward passage of the
pulverized substance on the bed; one of these sets of diagonal bars extends

page_text: from the left to the right in a diagonal direction across the table, while the
other set extends also diagonally, but in the opposite direction, from right to
Jeft across the first set, leaving spaces beneath.. The pulverized materials to
be operated upon are fed on to the table or bed at the top corner or end, and
as they pass down they will be lifted up slightly by the action of the puffs of
air from below until all the lightest particles reach the surface, and as they
accumulate they will pass over and between the diagonal bars from one to the
other until they reach the bottom, from whence they will ultimately pass off
at one corner while the heavier particles from their greater specific gravity
will remain behind until they so far accumulate as to be forced over the
lowermost diagonal bars and ultimately reach the lowest corner of the bottom
of the table from whence they will be delivered and at the opposite corner
from where the lighter particles leave the bed..
It will now be understood that as by the continual agitation caused by the
air the lighter particles will always have a tendency to come to the surface a
perfect, separation of the ore from its lighter impurities will take place,, and that
the action of the apparatus will be continuous.. In combination with the
separating apparatus there are mechanical appliances for crushing the ore and
drying, sifting, and bolting it so as to obtain the grains nearly of the same
size. The pulverized substances are also elevated in the mill and to the
separating table by mechanical means, so that the process may be continuous
and be carried on by steam or other power.