Improvements in Purifiers for Middlings and other Granular or Pulverulent Materials.
Year: 1891

page_text: Date of Application, 19th Aug., 1891
Complete Specification Left, 13th May, 1892-Accepted, 18th June, 1892
PROVISIONAL SPECIFICATION.
Improvements in Purifiers for Middlings and other Granular or
Pulverulent Materials.
We, JOHN SMITH, of Grove Iron Works, Carshalton, in the County of Surrey,
Engineer, and JOSIAH COURSE, of Grove Cottage, Carshalton aforesaid, Engineer,
do hereby declare the nature of this invention to be as follows:-
As usually constructed these machines have a large chamber directly over the
silk surface of the sieve, through which sieve an air current is drawn by means of
a fan fixed above the chamber, and in its ascent takes up particles of unequal
weight. Owing to the height of the chamber and the expansion of the air current
therein, the heavier portion of the impurities falls down on to the sieve again, thus
impeding the action of the machine. To counteract this defect trays or troughs
are sometimes fixed in the chamber to catch these heavier impurities, the result
being that the surface of the sieve is partially or entirely hidden and cannot there-
fore be examined or brushed on the top side, and consequently soon becomes
clogged and rendered incapable of producing good work.
According to our invention we construct the machine with a cover a short
distance above the sieve, and cause the dust laden air currents to be drawn through
regulating valves on each side of the machine below the cover, and through a long
and narrow space. Expansion chambers are fitted on both sides of the machine,
and the air currents being contracted in passing through the valves expand in the
chambers and thus allow the heavier particles to fall into the bottom, from whence
they are removed by worm or other conveyors.
The air currents now ascending are again expanded in a large central chamber
constructed over the cover previously mentioned, and here the lighter particles are
allowed to fall and are swept or conveyed to outlets, whence they are removed
from the machine.
The air which should now be practically pure, is then drawn through the
fan and can be allowed to discharge into the surrounding atmosphere, or if
preferred (in order to counteract any carelessness of the operator) it may be
gently blown into another chamber covered with a stationary filter cloth, which
can be cleaned by travelling brush, sweep, shaking, knocking or whipping, as most
convenient.
It is found in practice in all machines of this kind to be a troublesome
matter to keep the silk surface from choking, and for this purpose we provide
a series of reciprocating brushes fitted on a suitable frame under the silk, and
actuated by an oscillating lever, or any other ordinary motion; and we further
so construct the machine that the whole of the top surface of the silk is in
sight for inspection, and conveniently arranged so that it can be brushed by hand
at any time.
These improvements may be used either alone or in conjunction with the arrange-
ment described in the Specification of our prior application for Patent No. 3860
dated 4th March 1891, in which previous to the material to be treated falling upon
the sieve, it is caused to pass from a hopper on to a series of inclined or flat shelves
(either connected to the sieve or not), such material falling from one shelf to
another, and during its passage being acted upon by a gentle air current, so that
only the heavier portions pass on to the sieve for further treatment, the lighter
portions being carried off by the current of air and deposited in a suitable chamber
or chambers through which such current passes.
Dated this 19th day of August. 1891
ALLISON BROS.,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Purifiers for Middlings and other Granular or
Pulverulent Materials.
We, JOHN SMITH, of Grove Iron Works, Carshalton, in the County of Surrey,
Engineer, and JOSIAH COURSE, of Grove Cottage, Carshalton aforesaid, 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:-
As usually constructed these machines have a large chamber directly over the
silk surface of the sieve, through which sieve an air current is drawn by means of
a fan fixed above the chamber, and in its ascent takes up particles of unequal
weight. Owing to the height of the chamber and the expansion of the air current
therein, the heavier portion of the impurities falls down on to the sieve again,
thus impeding the action of the machine. To counteract this defect trays or
troughs are sometimes fixed in the chamber to catch these heavier impurities, the
result being that the surface of the sieve is partially or entirely hidden and
cannot therefore be examined or brushed on the top side, and consequently soon
becomes clogged and rendered incapable of producing good work.
The object of the present invention is to overcome these disadvantages.
In the accompanying drawings
Fig. 1 is a longitudinal section of a purifier constructed according to our inven-
tion, and
Fig. 2 is a transverse section of same.
According to our invention we construct the machine with a cover A a short
distance above the sieve B, and cause the dust laden air currents to be drawn
through regulating valves C on each side of the machine below the cover, and
through long narrow spaces or expansion chambers D, which are fitted on both
sides of the machine, so that the air currents being contracted in passing through
the valves C, expand in the chambers D, and thus allow the heavier particles to
fall into the bottom of such chambers, whence they are removed by worm or
other conveyors E.
The air currents now ascending are again expanded in a large central chamber G
constructed over the cover A, and here the lighter particles are allowed to fall
and are swept or conveyed by travelling brushes H or other suitable means to
outlets or troughs I, whence they are removed from the machine by worm or
other conveyors J.
The air which should now be practically pure, is then drawn through the fan K
and can be allowed to discharge directly into the atmosphere, or if preferred
(in order to counteract any carelessness of the operator) it may be gently blown
into another chamber L, covered with a stationary filter cloth M, which can be
cleaned by a travelling brush N, or by a sweep, shaking, knocking or whipping, as
most convenient.
It is found in practice in all machines of this kind to be a troublesome matter
to keep the silk surface B from choking, and for this purpose we provide a series
of reciprocating brushes fitted on a suitable frame P under the silk B, and
actuated by an oscillating lever Q, or by any other ordinary motion; and we
further so construct the machine that the whole of the top surface of the silk B
is in sight for inspection, and conveniently arranged so that it can be brushed by
hand at any time.
These improvements may be used alone, or as shown in the drawings they may
be used in combination with the arrangement described in the Specification of our
prior Patent No. 3860 dated 4th March 1891, in which previous to the material to
be treated falling upon the sieve B, it is caused to pass from a hopper a on to a
series of inclined or flat shelves b (either connected to the sieve B or not), such

page_text: material falling from one shelf to another, and during its passage being acted
upon by a gentle air current, so that only the heavier portions pass on to the sieve
for further treatment, the lighter portions being carried off by the current
of air and deposited in a suitable chamber or chambers d, through which such
current passes.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The employment of a cover A placed over the sieve B, and of valves C
between such cover and the sieve, through which valves air currents drawn
through the sieve are caused to pass, and are then expanded in suitable chambers D,
in which the heavier materials carried off by the air are deposited, substantially
as specified.
2. The combination with the arrangement set forth in the preceding claim, of a
central chamber G situated over the cover A above the sieve, and in which central
chamber G the air currents which have passed through the sieve B and chambers D
are further expanded, so as to effect a further deposition of any material contained
in such air currents, which latter then pass to the fan K, all substantially as
specified.
3. The combination with the chamber G and fan K, of a chamber L into which
the air currents drawn by fan K from chamber G are caused to pass, the top of
chamber L being closed by a stationary filtering cloth M through which the air
currents are delivered, substantially as specified.
4. The employment of a reciprocating brush O actuated by any suitable means
and bearing against the under surface of sieve B, so as to keep same from choking,
substantially as specified.
5. The improved machine for purifying middlings and other granular or
pulverulent materials, constructed and operating as herein described and as shown
in the drawings.
1
3
1000
ALLISON BROS.,
Agents for the Applicants.