IMPROVEMENTS IN SCREENS OR MACHINERY FOR CLEAN- ING WHEAT AND OTHER GRAIN
Year: 1853

page_text: PROVISIONAL SPECIFICATION left by Thomas Wilson at the
Office of the Commissioners of Patents, with his Petition, on the
21st June 1853.
(Void by reason of notice to proceed not having been given within the
time prescribed by the Act.)
I, THOMAS WILSON, of the City of Manchester, in the County of
Lancaster, Corn Factor and Miller, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN SCREENS OR MACHINERY FOR CLEAN-
ING WHEAT AND OTHER GRAIN" to be as follows:-
I employ the mode of cleaning grain hitherto in use, so far as
agitating or rubbing the grain upon a grating or screen which permits
dirt, chaff, or small particles of foreign matters to pass through, but
retains on its surface the grain, the screen being placed in such
position that such dirt, chaff, or foreign matters is separated from the
grain by its gravity; but a peculiarity of my Invention consists in
employing a vacuum or partial vacuum, which, by causing a current
of air from the screen, will assist gravity and the centrifugal action of
the drum, herein-after described, in the separation of the dirt, chaff,
and foreign matters from the grain. The novelty of the apparatus

page_text: which I employ consists in forming the screen or grating of the conical
form, or of a form approaching to that, placing its axis perpendicular;
and if the screen so formed be fixed with its larger end uppermost I
place within it a drum shaped to conform to the said screen, which
drum may be covered with brushes, bristles, wire cards, or iron bars,
which act against the grain when the drum is made to revolve upon
its axis, which is adjustable in an higher or lower position relative to
the screen, so that the brushes, bristles, wire cards, or iron bars can
be brought nearer to or further from the face of the screen. I case
the screen in on all sides so as to prevent admission of air, which can
have no ingress to the chamber of the screen but through the screen;
and with this chamber a fan of any ordinary construction is made to
communicate so as to produce a vacuum or a partial vacuum, and
thus induce a current of air from the screen or grating. The grain to
be operated upon is fed in at the top of the screen at one or more
places, and is conveyed away from the bottom of the screen when
operated upon by an air-tight pipe or passage till it is without the
screen chamber. If the axis of the screen be placed perpendicular,
with its larger end downwards, it may be made either fixed or to revolve
on its axis; if made fixed, the conforming drum will have to be at the
outside, covering the screen, its concave or inner side being covered
with brushes, bristles, wire card, or iron bars, & made to revolve
round the screen or grate; the grain to be operated upon being fed in
at the axis, with the other arrangements of casing and fan, as herein-
before described. If the screen be made to revolve, then the outer
case, with its concave side covered, as already mentioned, may be fixed,
the screen casing being modified to suit revolving motion. The advan-
tage of any of these arrangements are, that from the form & position
of the screen the whole of its surface is brought into operation.