Improvements in Machines for Cleaning and Polishing Grain and Rice.
Year: 1889

page_text: Date of Application, 5th Sept., 1889-Accepted, 12th Oct.,
1889
COMPLETE SPECIFICATION.
Improvements in Machines for Cleaning and Polishing Grain
and Rice.
I WILLIAM HOUGHTON, of Holme Street Works, Great Grimsby in the County of
Lincoln, Engineer and Millwright 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 :-
My Invention relates to an improved machine for scouring and cleaning grain and
for cleaning rice; and it consists essentially in the combination of a rotary horizontal
perforated table with a stationary brush disc (adapted to act on the grain as it is
carried round beneath it by the perforated table) and with a current of air passing
through the table whereby the grain is held over the perforations sufficiently to
cause it to be carried round with the rotary table and presented to the frictional
action of the brushes. The invention also comprises the accessory arrangements
for collecting separating and delivering the grain after being cleaned as above
mentioned.
In order that the invention may be more readily understood, reference must be
had to the accompanying drawings, forming part of this specification, wherein
figure 1 represents a central vertical section of the improved machine; figure 2 a
plan of the perforated rotary table; and figure 3 a detail of the mode of centreing the
rotary table. The same letters of reference indicate like parts in all the figures.
A is the circular table and B the annular brush disc, acting in conjunction there-
with. The table is constructed of perforated sheet metal upon a cast iron frame of
radial and concentric ribs keyed upon a vertical shaft C. The sheet metal table is
perforated with concentric circular rows of slits, the slits being placed as closely
together as possible and lying in an approximately radial direction, their divergence
from a truly radial direction being such as to partly counteract the centrifugal
action imparted to the grain by the rotating table and cause the grain to be suffi-
ciently detained under the action of the brushes to ensure a thoroughly effective
cleaning action. This action is further supplemented by the air current passing
through the rotating table carrying away all impurities immediately they are detached
from the grain.
In the drawing, one segment only of the table is shewn as perforated but it will
be understood that the entire table is similarly constructed.
The rim of the table A projects over the inner wall of a circular trough contained
within a casing D, E, enclosing the table and brush discs and the grain upon finally
escaping from the action of the brush falls into the said trough and is carried round
to the delivery aperture f in the bottom of the trough by pallets a attached to the
table and carried round in the trough.
The brush B is made of bristles set in a wooden back in the ordinary way or
instead of bristles wire might be used. The back of the brush is in the form of an
annular disc which is fixed to the upper part E of the casing, the brush surface pro-
jecting down towards, but not quite touching, the table A, the interval between the
brush and table being variable by means of set screws d, connecting the two parts DE
of the casing, by adjusting which the capacity of the machine and the extent of
cleaning which the grain undergoes is regulated. The upper pari E of the casing is
provided with a central aperture corresponding to the aperture 6 in the brush disc
and surmounted by a hopper G at which the grain to be cleaned is fed into the
machine. This feed hopper carries the upper bearing of the shaft C, said bearing
being constructed of segments h held in radial slots in a block h¹ supported by cross-
arms carried by the hopper the segments being adjusted, for centreing the shaft
and taking up wear, by means of set screws h².

page_text: Upon the shaft C is mounted a fan I situated beneath the table in a space separated
therefrom by an annular division J through the central aperture of which the air is
drawn down through the perforations of the table as well as through the feed hopper
and discharge spouts. The discharge outlet f from the trough leads into a vertical
delivery spout at the bottom of which the cleaned grain is delivered. The upper
part of the delivery spout communicates with an exhaust passage K leading across
the machine to a winnowing hopper-shaped chamber L at which the small grain and
refuse is collected and discharged at intervals whilst the continuation K² of the
exhaust passage leads into the space between the table A and partition J. The
winnowing chamber L is provided with an air inlet & controlled by a regulator and
the discharge mouth of the hopper is furnished with valves which together constitute
a sort of air lock permitting of the collection and discharge of the small grain and
refuse. The table A is rotated at a speed of about four hundred revolutions per
minute, by a belt running on the pulley M fast on the shaft C.
The perforated sheet metal table top is fixed upon its supporting frame by bolts a¹
whose rounded heads project above the surface of the table for the purpose of dis-
turbing the bristles of the brush and preventing them clogging. In order that the
whole surface of the brush may be acted upon, the bolt heads are disposed in a spiral
series, as shewn in figure 2. The table A has a beading a² near its edge standing up
from its face about as high as the bolt-beads and serving to detain the grain under
the action of the brushes before it finally escapes into the trough. In figure 1, the
brush is for convenience of illustration shewn as raised clear of the bolt heads a¹. The
feathered arrows shew the course of the grain whilst the featherless arrows shew that
of the air.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is;
1. The herein described machine for cleaning and scouring grain and rice, con-
structed and operating substantially as specified."
2. In a machine for the purpose specified, the combination of the rotary table,
perforated as described, with the stationary brush and with an exhaust fan or equiva-
lent means of producing an air current through the perforations of the table and of so
detaining the grain under the action of the brushes, substantially as specified.
Dated this 5th day of September 1885.
Dated GIS on day of September 2009.
WM. HOUGHTON.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.