IMPROVEMENTS IN ROTARY CORN SCREENS FOR DRESSING AND SEPARATING GRAIN
Year: 1870

page_text: LETTERS PATENT to William Rainforth, senior, of Brayford Head,
Lincoln, in the County of Lincolnshire, and William Rainforth,
junior, of the same Place, Wire Workers and Weavers, for the
Invention of "IMPROVEMENTS IN ROTARY CORN SCREENS FOR DRESSING
AND SEPARATING GRAIN."
Scaled the 24th May 1870, and dated the 16th March 1870.
PROVISIONAL SPECIFICATION left by the said William Rainforth,
senior, and William Rainforth, junior, at the Office of the Com-
missioners of Patents, with their Petition, on the 16th March
1870.
We, WILLIAM RAINFORTH, senior, of Brayford Head, Lincoln, in the
County of Lincolnshire, and WILLIAM RAINFORTH, junior, of the same
Place, Wireworkers and Weavers, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN ROTARY CORN SCREENS FOR DRESSSING
AND SEPARATING GRAIN," to be as follows:-
In constructing rotary screens for dressing and separating grain it is
desirable that they should be capable of being compressed or expanded
so as to be able to diminish or increase the spaces between the wires

page_text: (forming the screen), thus allowing for the effective and proper
screening of the corn or other grain to be dressed or separated.
The construction of the new and improved screen is as follows:- -A
single wire of the necessary thickness is first coiled round in a helical
direction (making thereby a wire cylinder and forming as it were the
foundation of the after work in the construction of the screen), the
cylinder formed being made of any necessary length. Cross wires arc
then interwoven with the continuous helical wire (composing the
cylinder) over and under each alternate round of the same, by this
means forming a cylinder with square meshes. Each alternate cross
wire is bent round at one of its ends, and secured by this bent part to
the last round of the helical wire at one end of the cylinder. The other
alternate cross wires are in a similar manner bent (but at the opposite
cnd) and secured to the last round of the helical wire at the other end
of the cylinder, the ends of the cross wires not bent are left free. To
form this circular screen with square meshes into the proper screen it is
compressed, during which operation it slightly turns, and in such a
manner that the cross wires now run in a helical direction from one end
of the now formed screen to the other; by this means the cross wires
form with the first-mentioned helical wire a diamond mesh, the spaces
between the helical wire becoming at the same time narrower by reason
of the compression. By this simple operation a circular screen is formed
with a corrugated inside formed by the interweaving of the cross wires
and the helical wire. The ends of the helical wire are placed or seated
in perforated discs or in rims provided with arms radiating from the
axis, to which a traversing screw is fixed for carrying along the grain.
To the axis of the screen these perforated discs or annular rims are
connected in such a manner that one of them is fixed to the same,
whilst the other is made capable of sliding over it. A third and also
movable disc or rim is placed at about the centre of the screen to
strengthen and support the wirework of the same. The expansion and
compression of the screen or the elongation and shortening of the same
may be effected in any well known or convenient manner. The rotation
of the screen may also be effected by any convenient apparatus.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Rainforth, senior, and William Rain-
forth, junior, in the Great Seal Patent Office on the 16th September
1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, WILLIAM
RAINFORTH, senior, of Brayford Head, Lincoln, in the County of
Lincolnshire, and WILLIAM RAINFORTH, junior, of the same Place,
Wire Workers and Weavers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by. Her
Letters Patent, bearing date the Sixteenth day of March, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto us, the said William Rainforth, senior, and William
Rainforth, junior, Her special licence that we, the said William Rain-
forth, senior, and William Rainforth, junior, our executors, adminis-
trators, and assigns, or such others as we, the said William Rainforth,
senior, and William Rainforth, junior, our executors, administrators,
and assigns, should at any time agree with and no 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 "IMPROVEMENTS IN ROTARY CORN SCREENS
FOR DRESSING AND SEPARATING GRAIN," upon the condition (amongst others)
that we, the said William Rainforth, senior, and William Rainforth,
junior, our exccutors or administrators, by an instrument in writing
under our, or one of our, 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 we, the said William Rainforth, senior, and
William Rainforth, junior, do hereby declare the nature of our said
Invention, and in what manner the same is to be performed, to be par-
ticularly described and ascertained in and by the following statement

page_text: in writing, reference being had to the accompanying Sheet of Drawings,
that is to say:-
In constructing rotary screens for dressing and separating grain it is
desirable that they should be capable of being compressed or expanded
so as to be able to diminish or increase the spaces between the wires
(forming the screen) thus allowing for the effective and proper screening
of the corn or other grain to be dressed or separated.
The construction of the new and improved screen is as follows:-A
single wire of the necessary thickness is first coiled round in a helical
direction (making thereby a wire cylinder and forming as it were the
foundation of the afterwork in the construction of the screen) the
cylinder formed being of any necessary length. Cross wires are then
interwoven with the continuous helical wire (composing the cylinder)
over and under each alternate round of the same, by this means forming
a cylinder with square or as in some instances herein-after mentioned
rectangular meshes. Each alternate cross wire is bent round at one of
its ends and secured by this bent part to the last round of the helical
wire at one end of the cylinder. The other alternate cross wires are in
a similar manner bent (but at the opposite end) and secured to the last
round of the helical wire at the other end of the cylinder, the ends of
the cross wires not bent are left free. To form this circular screen with
square or rectangular form of meshes into the proper screen it is
compressed, during which operation it slightly turns, and in such a
manner that the cross wires now run in a helical direction from one end
of the now formed screen to the other, by this means the cross wires
form with the first-mentioned helical wire a diamond mesh, the spaces
between the helical wire becoming at the same time narrower by reason
of the compression. By this simple operation a circular screen is
formed with a corrugated inside formed by the interweaving of the
cross wires and the helical wire. The ends of the helical wire are
placed or seated in perforated discs or in rims provided with arms
radiating from the axis to which a traversing screw or worm is fixed for
carrying along the grain. To the axis of the screen these perforated
discs or annular rims are connected in such a manner that one of them
is fixed to the same whilst the other is made capable of sliding over it.
A third and also moveable disc or rim is placed at about the centre of
the screen to strengthen and support the wirework of the same. The

page_text: expansion and compression of the screen or the elongation and
shortening of the same may be effected in any well-known or convenient
manner. The rotation of the screen may also be effected by any
convenient apparatus.
Such being the nature and object of our said Invention for "Im-
provements in Rotary Corn Screens for Dressing and Separating Grain,"
we will now proceed to describe more in detail the manner in which the
same is to be or may be performed or carried into practical effect, and in
order that the same may be distinctly understood we have annexed here-
unto a Sheet of Drawings illustrative thereof, and have marked the same
with figures and letters of reference corresponding with those in the
following explanation thereof, that is to say :-
On the accompanying Sheet of Drawings Figure 1 represents a side view
of the improved screen placed in position, and as ready for working. This
Figure at c represents only the nearer side of the wirework of the screen,
so as more clearly to show the principle and manner on and in which
the screen is constructed. A part a of it, however, exhibits the wires also
at the other side of the screen, and also in the part b; the wire d is only
shown in order to show the manner in which the screen is compressed
when desired. Figure 2 is a longitudinal vertical section of the tube
shaft or hollow axis c with inside screwed rods of three (or more, as
the case may be, according to the number of rims) different pitches of
thread. Figures 3 show the manner of first "building up or forming
the improved screen.
"
The construction of the improved screen will be readily understood,
reference being had to the accompanying Drawings. The wire d is
first coiled round in a helical direction (as at b, Figure 1,) so as to form
a cylinder of any required diameter and length, and thereby forms the
foundation of the screen. The cross wires e are then interwoven (as
shown at Figures 3) with the continuous wire d, thereby forming a
cylinder with the square or rectangular form of mesh. For different
sorts, sizes, or kinds of grains it may, however be more convenient
to leave out each alternate wire e as shewn in the centre example of
Figures 3, or for particular sorts to add another between as shewn at
the left example of Figures 3. Each alternate wire e is bent round (at
one end,) the last round f of the wire d, which fits in a disc or rim g.
The other alternate wires e are bent in a similar manner, but to the

page_text: other last round of the wire d, which also fits in one of the rims g, the
other end of the wires may be left free. To form this screen with the
square or rectangular meshes into the proper screen suitable for sepa-
rating and dressing the grain, it is compressed, and in this operation it
slightly turns, and in such a manner that the cross wires now run in a
helical direction, and thereby form with the helical wire d a diamond
or elongated mesh, as shown at Figure 1, the spaces between the rounds
of the wire d becoming also smaller and narrower by reason of the
compression. By this simple operation the screen is formed with a
corrugated inside, formed by the interweaving of the wires e with the
wire d, and aided by the compression of the cylinder, which bends or
inclines the wires, and forms the diamond or elongated corrugated
meshes in the manner shown at Figure 1. The last round of the wire
at each end is seated in one of the perforated discs or rims g, g', pro-
vided with arms radiating from the shaft or hollow axis c* ; a traversing
worm, not shown on the Drawings, of any suitable shape is or may be
affixed to the interior surface of the cylinder to carry along the grain
at any desired speed. The rim or disc g¹ is attached to the boss g²,
which boss is keyed and fixed to the shaft c, whilst the other discs g are
not keyed to the shaft, but are capable of sliding upon it. The rims
between the two extreme ones are for the purpose of strengthening or
supporting the wirework of the centre part of the screen, if of any
considerable length, and by a suitable modification of a convenient and
well-known arrangement of mechanism in connection with the shaft c,
the wirework forming the screen between each or any two of these
rims may be made to assume or have a different mesh, so that the finest
grain may be made to escape from the screen first (say from the partj),
then a coarser size, (say from the part k) and then the coarsest (say
from the nart A

page_text: inserted in the screen. The use of this will be hereafter explained.
Inside the tube and round these screwed parts (which correspond to
the slits in the tube or shaft) are placed nuts 9; these nuts are con-
nected to the bosses (capable of sliding on the shaft c*) of the rims g,
which bosses are connected to the arms of the rims g. The inside
screwed rod 8 terminates at u, where it is squared so as to be capable of
being turned by a handle or key. When this is performed, by reason of
the difference in the threads of the parts n, o, p, the 3 rims 7 will be
caused to move at different rates which will however have the effect of
causing the meshes of the 3 parts j, k, l, to be similarly altered and
narrowed or widened as the case may be. The parts o, p, having
respectively and ½, as many threads as the part n, the rims to
which the nuts working over those parts are separately connected will
consequently be caused to advance along the axis and rod twice and
three times respectively, as fast as the rim connected to the nut working
over the screwed part n. For example, if the rim farthest from the
squared end u is made by the rotation of the shaft 8 to move three
inches, the one nearer will be caused to move six, and the nearest nine,
thereby narrowing each separate part j, k, l, three inches. The block t
is fixed to the tube and has a hole formed through it, the rod at this
point has also a number of holes passing through, so that when the gauge
of the wires is set as desired, a pin is passed through these holes and the
nuts are prevented from being turned. y and z are partitions for dividing
the grain, and v, w, x, are shoots for the different sizes of the same. The
rotation of the screen may be effected by means of a belt passing round
the pulley or by any convenient means.
Having now. described the nature and object of our said Invention
for "Improvements in Rotary Corn Screens for Dressing and Separating
Grain," together with the manner in which the same is to be or may
be performed or carried into practical effect, we would remark in con-
clusion that we claim as our Invention the new and improved construc-
tion of the rotary screen, substantially as herein-before described and
as shown on the accompanying Sheet of Drawings, or any mere modi-
fication thereof. And we would also remark that we claim the placing
of the discs in different parts of the wirework of the screen, and the
means of working them, substantially as described and illustrated on
the accompanying Sheet of Drawings, and for the purposes enumerated,
namely,

page_text: Firstу. 10 strengthen.
And, secondly. So as to allow of the screen having different parts of
the same divided into different sized meshes for the more proper separa-
tion and assortment of the various sized grain.
In witness whereof, we, the said William Rainforth, senior, and
William Rainforth, junior, have hereunto set our hands and seals,
this Thirteenth day of September, in the year of our Lord One
thousand eight hundred and seventy.