AN IMPROVED CONSTRUCTION OF SCREEN FOR SCREENING CORN
Year: 1871

page_text: LETTERS PATENT to Robert Boby, of Bury St. Edmunds, in the
County of Suffolk, Machinist, for the Invention of "AN IMPROVED
CONSTRUCTION OF SCREEN FOR SCREENING CORN."
Scaled the 18th August 1871, and dated the 14th March 1871.
PROVISIONAL SPECIFICATION left by the said Robert Boby at the
Office of the Commissioners of Patents, with his Petition, on the
14th March 1871.
I, ROBERT BOBY, of Bury St. Edmunds, in the County of Suffolk,
Machinist, do hereby declare the nature of the said Invention for
"AN IMPROVED CONSTRUCTION OF SCREEN FOR SCREENING CORN," to be as
follows:-
:-
The object of this Invention is to provide a self-acting screen for
screening corn, the weight of the corn as it descends from an elevation
being employed for working the screen. The grid of the screen I fix at
a suitable inclination, and I connect it at its upper end with a hopper
which is supplied by an elevator or otherwise, for the corn to be screened.
Between the longitudinal parallel rods of the grid I insert small disea

page_text: or projecting pieces, which are intended to traverse the spaces between.
the longitudinal rods and the transverse bars that support those rods,.
for the purpose of keeping the spaces, open. These discs or projections
are carried by transverse rods, fitted to side bars that slide over the sides
of the fixed screen, the sides of the screen being slotted to allow of this
traverse motion of the rods. Pivotted to the side bars on either side
of the screen is a pair of crank rods which connect with double-throw
cranks carried by a horizontal shaft below the foot of the screen.
Mounted on this crank shaft is a bucket wheel or drum of the breadth
of the screen, and so situated with respect thereto as to, receive (as, an
overshot wheel), the screened corn as it leaves the screen. The weight
of this falling grain acts upon the bucket wheel to give a rotary motion
thereto. This motion is communicated through the cranks and crank
rods to the sliding bars that connect the rods of the screen clearers.
together and thus an automatic traverse motion is given to the screen
clearers through the descent of the corn from the elevated hopper.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Boby in the Great Seal Patent Office on
the 14th September 1871..
TO ALL TO WHOM THESE PRESENTS, SHALL COME; I, ROBERT
BOBY,, of Bury St. Edmunds, in the County of Suffolk, Machinist, send
greeting.
WHEREAS Her. most Excellent Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Fourteenth day of March, in the year.
of our Lord One thousand eight hundred and seventy-one, in the 2
thirty-fourth year. of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Boby,, Her special
licence that I, the said Robert Boby, my executors, administrators,,
and assigns, or such others, as I, the said Robert Boby, my executors,
administrators, and assigns, should at any time agree with, and no 3
others, from time to time and at all times thereafter. during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "AN IMPROVED
CONSTRUCTION OF SCREEN FOR SCREENING CORN," upon the condition (amongst 3

page_text: others) that I, the said Robert Boby, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Robert Boby, do hereby declare
the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement; reference being had to the Drawing hereunto
annexed, and to the letters and figures marked thereon (that is to
say):
The object of this Invention is to provide a self-acting clearer for
screens: used for screening grain or seeds, the weight of the grain as it
descends from an elevation being employed for working the clearer.
In the accompanying Drawing my improved screen is shewn in
longitudinal sectional elevation at Fig. 1. A is the grid of the screen,
which is fixed at any suitable inclination, and connected with it at its
upper end is a hopper B.; this hopper is supplied by an elevator or
otherwise with the corn to be screened, which corn it delivers on to the
grid A through the intervention of a bucket wheel C for the purpose
to be presently explained.
Fig. 2 shews in partial plan view, and Fig. 3 in cross section on an
enlarged scale, the grid with the improved clearer applied thereto, and
Fig. 4 is a partial longitudinal section of the same. The grid consists of
a series of longitudinal, parallel, round, or other shaped rods a held
together by being passed through holes or notches formed in transverse.
bars 6 to receive them, which bars are secured at their ends to side
pieces c. Between the longitudinal parallel rods a of the grid I insert
small discs or projecting pieces d, which are intended to traverse the
spaces between the longitudinal rods and the transverse bars b, for the
purpose of keeping the spaces open. These discs or projections are
carried by transverse rods e fitted to side bars that slide over the
sides c of the fixed screen, the sides of the screen being slotted, as shewn
at Fig. 1, to allow of this traverse motion of the rods and to form guides
for those rods. Pivotted to the side bars f on either side of the screen.
is a pair of crank rods D, which connect with double-throw cranks E

page_text: carried by a transverse shaft F mounted in bearings in the side framing
of the machine. This shaft F forms the axle of the bucket wheel C,
which is keyed fast to its axle. This bucket wheel is so situated with
respect to the hopper and the grid as to receive the corn as it falls from
the hopper and deliver it on to the grid. The weight of the stream of
falling grain serves to give to the bucket wheel a rotary motion, which
motion is communicated through the cranks E and crank rods D to the
sliding bars that connect the rods of the screen clearers together, and
thus an automatic traverse motion is given to the screen clearers
through the descent of the corn from the elevated hopper.
Having now set forth the nature of my Invention of "An Improved
Construction of Screen for Screening Corn," and explained the manner
of carrying the same into effect, I wish it to be understood that under
the above in part recited Letters Patent I claim, the application to
corn screens of traversing clearers constructed and operated as above
described.
In witness whereof, I, the said Robert Boby, have hereunto set
my hand and seal, the Twelfth day of September, in the year of
our Lord One thousand eight hundred and seventy-one.