Improvements in Grain Cleaning and Separating Platform Sieves or Screens.
Year: 1892

page_text: Date of Application, 24th Mar., 1892
Complete Specification Left. 21st Oct., 1892-Accepted, 26th Nov., 1892
PROVISIONAL SPECIFICATION.
[Communicated from abroad by CHARLES CLOSZ, of St. Ansgar, Mitchell County,
Iowa, U.S.A., Miller.]
Improvements in Grain Cleaning and Separating Platform Sieves or
Screens.
I, REGINALD WALTER BARKER, of Monument Chambers, King William Street,
London, Middlesex, Patent Agent, do hereby declare the nature of this invention
to be as follows:-
My invention relates to grain cleaning and separating platform sieves or screens,
and more particularly to that class of sieves or screens wherein the openings or
perforations are arranged in rows along the sides of inverted V shaped corrugations,
said rows or series of rows running lengthwise of the sheets.
Cyma shaped incisions or perforations are stamped out of the metal, from which
the openings are formed by depressing and elevating certain parts of the metal
adjacent to said perforations. The cyma shaped perforation of the metal is essential
to the peculiar form of the openings. While it is preferable to arrange the series
of openings on both sides of alternate corrugations, they may be arranged on one
side of each corrugation, or on both sides of all the corrugations leaving none of the
latter blank, without departing from the principle of the invention.
This arrangement of the openings along the sides of corrugations, supplemented
by the curvatures of the metal in the formation of the openings, makes the sieve
desirably strong and durable, and allows of a comparatively large discharge and
screening surface.
The peculiar curvature and elevation of the openings prevents the clogging or
choking of the same.
Dated this 21th den of Monch 1800
REGINALD W. BARKER.
COMPLETE SPECIFICATION.
Improvements in Grain Cleaning and Separating Platform Sieves or
Screens.
I, REGINALD WALTER BARKER, of Monument Chambers, King William
Street, London, Middlesex, Patent Agent, 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 :-
The improvement herein is directed to the production of a sheet-metal-platform
screen adapted to clean and separate wheat from straws, weeds, and other kinds
of grain, particularly oats, and is designed for use in thrashing machines, receiving
and milling separators and farming mills, and for either end shake or side shake
machines. The surface construction of the screen is such as to effect the freest
possible separation and discharge of the wheat through its openings and to effect
the freest possible passage of such grain and foreign substances as ought to be
carried out over the screen and to prevent choking or clogging with large
screening capacity. The particular features of novelty in this surface construction
will be pointed out in the claims concluding this Specification, in connection with
the accompanying drawings, in which―
Figure 1 represents in top view so much of a sheet metal platform screen as
illustrates my improvement.
Fig. 2 is a vertical longitudinal section of the same on the line a of Fig. 1.

page_text: Fig. 3 is a cross section on the line b, looking toward the receiving end of the
screen.
Fig. 4 is a similar view on the line c, looking toward the discharge end of the
screen.
Fig. 5 is a detail in section on the line d.
Fig. 6 is a detail in perspective of a portion of the screening surface.
Fig. 7 shows enlarged in top view two of the lobed openings, and
Fig. 8 a side view of the same.
.
7
The platform is constructed of longitudinal parallel corrugations of unequal
width and preferably of unequal height, the widest, 1, of which are formed with the
separating openings, and the narrowest, 2, forming surface channels or passages 3 for
carrying off the foreign matter. The sides of the widest corrugations are preferably
slightly concave and are formed with openings, which stand obliquely upward and
forward from the base line of the channels. These openings are made by a single cut,
the curvature of which conforms as nearly as possible to the line of beauty or cyma.
That edge of the line of beauty which terminates near the ridge 1 of the corru-
gations is raised and stands forward like an ear, the lobe 4 of which rises preferably
slightly above the top line of the corrugation and overhangs that part of the
opening. That edge of the line of beauty which terminates at the base line of
the channels is depressed and stands backward like an ear, the lobe 5 of which
underhangs that part of the opening. The forward standing lobes 4 form concave
backs the inclination of which begins at the base line of the channels and increases
in pitch to the upper end of the lobe, while the inclination of the rearward
standing under ears is greatest near the base line, and with the forward standing
edge forms a crescent shaped opening, looking with a bird's eye view, which
obliquely crosses the channel. The under ear lobes 5 are formed with an abrupt
concavity 6, Fig. 7, in their widest surface, which terminates in an abrupt knoll 7
just under the side edge 8 of the upper forward standing lobe, and between this
knoll 7 and the forward standing lobe 4 the surface is slightly concave, and this
concavity extends down to the base line and forms a sort of basin 9 in the channel
between the openings. A slight surface ridge 10 is formed obliquely across the
channel at the line of the bend of the under car lobe, so as to facilitate the dis-
charge of the grain by forming a sort of dividing line between the under sloping
concave surface 6 of the ear lobe 5 and the upper concave surface basin 9.
openings and the lobe surfaces 4 over them and leading thereto give a sidewise
discharge of the grain through the openings from the concave side of the corru-
gation and a discharge of the grain through the openings in the line of its
movement in the channels, which gives a large screening capacity, while the forward
standing lobes along the upper side of the corrugation prevent the lodging or
sticking of anything in the openings. These openings are preferably coincident
on the opposite sides of the corrugations; but they may be placed in alternate
order, the essential feature being the form of the openings, the lobes covering their
upper forward standing ends and terminating in the uncovered ends of said
openings obliquely across the channels. The imperforate corrugations give
strength and increase the rigidity of the platform and form one side of each
channel; but they may also be formed with openings herein described, or one side
only of each corrugation may be imperforate and give good results, and the
imperforate corrugation may be only a shallow ridge.
The
In separating oats from wheat the peculiar curved and inclined lobes over the
upper part only of the openings tend to file the oats downward into the base track
or line, and thereby cause their movement lengthwise across the openings, which at
this point freely permit the passage of the shorter grains of wheat through them, as
at this point the concave downward sloping surface increases the width of the
opening. The convex projection or knoll 7 and the oblique ridge 10 are
advantageous to form a dividing line for supporting and for separating the oats
and the wheat at the exposed part of the opening and for preventing the backward
action of the grain and checking it at the base of the opening. These various

page_text: surface parts co-operate to give a free forward movement of weeds and straws and
screen the grain therefrom, while the lobes standing forward near the ridge of the
V shaped corrugation serve effectively in agitating and facilitating the forward
movement of the chaff and straw on the ridges of the corrugations between the
lobes and over their sloping backs. The curve of the upper end of the openings is
preferably shorter than that which extends down to the base line of the channel, so
as to form comparatively small ear lobes along the corrugated surface near the
ridge and comparatively large openings along the channels, and these lobes may be
comparatively flat on their upper surface, or they may be turned up with a bend
and form, in connection with the unbroken surface of the ridge, an elevated smooth
ridge having openings shielded at the side thereof and exposed along the channel,
one side of which is bounded by the imperforate corrugation. When the ridge
lobes are made flat, the concave edge of the opening is depressed to give the
required width of opening under the lobes. The openings are made a suitable
distance apart and the degree of their forward standing inclination is such as to
give a free movement of the grain and stuff over the raised parts along the ridge
and along the channel. It will be understood that the length of the openings will
be governed by the degree of their inclination in the sides of the corrugations and
that by reason of being so peculiarly guarded at their upper ends and exposed at
their lower ends along the base channel give an increased screening capacity to the
screen, which is very advantageous under a crowded flow over the surface, as the
grain is thereby caused to discharge along the entire opening, while under a light
flow the discharge is along the base channels. It will also be understood that the
openings formed and guarded, as stated, may be arranged at right angles to the
line of overflow.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A corrugated sheet metal platform screen having openings of cyma form in
the sides of the corrugations terminating in the channel in under rearward sloping
ear lobes, for the purpose stated.
2. A corrugated sheet metal platform screen having openings of cyma form in
the sides of the corrugations terminating in the channel in under rearward sloping
ear lobes formed with abrupt cavities crossing the line of the channel, for the
purpose stated.
3. A corrugated sheet metal platform screen having openings of cyma form, the
upper convex edges whereof terminate in forward standing ear lobes along the sides
of the ridge of the corrugation, the lower convex edges of said openings terminating
in the channels in under rearward sloping ear lobes along the base line of the
corrugation, for the purpose stated.
4. A corrugated sheet metal platform screen having openings of cyma
form, the upper convex edges whereof terminate in forward standing ear lobes
along the sides of the ridge of the corrugation, the lower convex edges of said
openings terminating in the channel in under rearward sloping ear lobes joining the
base line of the corrugation and formed with an abrupt concavity, an abrupt
convexity, and an oblique ridge crossing the channel at the surface thereof, for the
purpose stated.
5. A corrugated sheet metal platform screen having cyma formed openings
obliquely standing in the sides of the corrugations, shielded at their upper ends
along the sides of the ridge and having their lower ends exposed in the channels,
for the purpose stated.
6. A sheet-metal platform screen formed with alternating wide and narrow
corrugations, the sides of the widest corrugations slightly concave and having
openings of cyma form standing obliquely and formed with concave ear lobes along
and below the channel, sloping downward and rearward into the lower ends of said
openings, for the purpose stated.

page_text: 7. A corrugated sheet metal platform having cyma formed openings supplemented
t their upper ends by lobes inclining forward and upward on the side of the ridge,
for the purpose stated.
8. A sheet metal platform screen having longitudinal parallel ridges rising from
the base channels and forming sloping concave surfaces having openings standing
upward therein, supplemented at their upper ends by forward standing lobes having
sloping backs, for the purpose stated.
9. A sheet metal platform screen having longitudinal parallel corrugations pro-
vided with sidewise standing openings supplemented at their upper ends with
forward standing lobes and terminating in uncovered ends crossing the base
channels, for the purpose stated.
10. A sheet metal platform screen formed with longitudinal parallel corrugations
having openings standing crosswise in the sides thereof, supplemented at their
upper ends by forward standing lobes, their lower ends exposed along the channels
bounded on one side by an imperforate corrugation, for the purpose stated.
Dated this 20th day of October 1892.
REGINALD W. BARKER.