IMPROVEMENTS IN WINNOWING AND GRAIN DRESSING MACHINES
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by Thomas Corbett at the Office of
the Commissioners of Patents, with his Petition, on the 29th May
1872.
I, THOMAS CORBETT, of Shrewsbury, in the County of Salop,
Agricultural Implement Manufacturer, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN WINNOWING AND GRAIN
DRESSING MACHINES," to be as follows:-
My Invention consists of the construction and combinations or
arrangements, herein-after described, of the parts of winnowing and
grain dressing machines.
In the ordinary winnowing and grain dressing machine the riddle
frame turns upon a centre at one of its ends, motion being com-
municated by a crank at the other end. The motion of the said
riddle frame is consequently curvilinear, and the different parts move
with different velocities.
According to my Invention I suspend the riddle frame by chains
or slings, and communicate motion to the said riddle frame at its

page_text: middle so as to give it a rectilinear transverse motion, every part of
the riddle frame and riddles moving at the same time and with the
same speed; by this arrangement the grain is better opened for the
operation of the blast from the fan, and is consequently better dressed.
The gearing employed may be the ordinary gearing, the shaft being
shortened so as to connect the crank wheel carried at its end with the
middle of the side of the riddle frame; other gearing may however
be employed. I drive the screens of the said machines in the following
manner :- -On each end of the fan shaft I fix a crank wheel connecting
rods from the said crank wheels being jointed to the upper end of the
screen. The said screen may be connected to the riddle frame, sus-
pended in the manner herein-before described. In this case both the
riddle frame and screen are driven by the crank wheels and connecting
rods described, but instead of jointing the connecting rods to the top
of the screen I joint them to the connecting pieces by which the riddle
frame and screen are connected together.
I drive the riddle frame of the said machines by the following
arrangement :-I dispense with all the ordinary gearing used for
driving the said riddle frame, and connect the riddle frame with the
screen by means of a connecting rod jointed at one end to the said
riddle frame and at the other end to the screen, the said rod passing
diagonally under the riddle. By the advancing and retiring motion
of the screen a transverse reciprocating motion is communicated to the
riddle frame and riddles by the said diagonal connecting rod.
I make the feeding rollers of the said machines of a cylindrical figure,
and provide them with a series of rows of moveable spikes, by the
addition or removal of which spikes the rollers may be used as smooth
feeding rollers or as spiked feeding rollers. The hopper slide is fur-
nished with a number of slits through which the spikes of the feeding
roller pass, and by means of a sliding cover on the hopper slide the slits
in the said slide may be covered when the roller is employed as a smooth
feeding roller.
The hariff or bearded seed is separated from the grain by the following
arrangement :—Two hoppers are employed from one of which the grain
falls into the other. Inside the lower hopper two horizontal rollers are
fixed over which an endless web of flannel or other fabric works, the
said fabric forming one of the inclined sides of the said lower hopper.

page_text: As the mixture of grain and hariff falls from the first hopper on to
the said endless web and is carried down thereon to the riddle, the
hariff attaches itself to the web, the grain passing from the said hopper
to the riddle. The hariff being carried on the ascending side of the
web is brought against a scraper situated near the upper roller, by the
action of which scraper the hariff is removed from the said web and
falls into the refuse spout of the machine.