Improvements in Self-cleaning Revolving Screens.
Year: 1892

page_text: Date of Application, 23rd Mar., 1892
Complete Specification Left, 8th Dec., 1892-Accepted, 4th Feb., 1893
PROVISIONAL SPECIFICATION.
Improvements in Self-cleaning Revolving Screens.
We, WILLIAM HORNSBY, ROBERT EDWARDS, JEREMIAH MONEY and
SAMUEL MANNING, all of Spittlegate Ironworks, Grantham, in the County of
Lincoln, Engineers, do hereby declare the nature of this invention to be as
follows:-
This invention relates to an improved form of self-cleaning revolving screen.
The screen which is made of wire and mounted on a horizontal spindle is of circular
shape, but of variable diameter, its diameter being largest at or about the middle of
its length, and gradually diminishing towards the ends. The middle of the screen
is attached to and driven by a centre piece which encircles the spindle and rotates
thereon but which is arranged to slide endways on the spindle.
The ends of the screen are attached to centre pieces revolving on bearings
mounted diagonally on the spindle, the said spindle revolving inside them, and the
bearings are held from turning by a projection which rests on the frame that carries
the screen.
These diagonal bearings cause the end centres of the screen to slant
outwards at the top so that when the screen is working the bottom part or underside
of it is approximately in a straight line whilst the top tapers off from its middle to
each end, so that when revolved it causes a slight movement of the wires, so that
any grain held between the wires will drop out from the sides or the upper part of
the screen as it revolves.
At the end of the screen where the grain is fed into it, the diagonal end bearing
is fixed, so that it cannot be moved endways but the diagonal bearing at the other
end can be moved end ways for adjusting the length of the screen.
The screen can be adjusted in length by having its wires moved closer together
or farther apart by a screw placed inside its spindle at one end and having two
threads one of which engages in the central or driving centre and the other in one
of the outside end centres, whilst the other end of the screw spindle is fixed as
regards end movement relatively to the screen spindle.
Dated the 23rd day of March 1892.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Self-cleaning Revolving Screens.
We, WILLIAM HORNSBY, ROBERT EDWARDS, JEREMIAH MONEY and
SAMUEL MANNING, all of Spittlegate Ironworks, Grantham, in the County of
Lincoln, Engineers, 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 :-
This invention relates to an improved form of self-cleaning revolving screen.
The screen which is made of wire and mounted on a horizontal spindle is of circular
shape in transverse section but of variable diameter, its diameter being largest at
or about the middle of its length, and gradually diminishing towards the ends.
The middle of the screen is attached to and driven by a centre piece which encircles
the spindle and rotates therewith but which is arranged to slide endways on the
spindle.
The ends of the screen are attached to end pieces revolving on bearings or sleeves
mounted diagonally on the spindle, the said spindle revolving inside them, and the

page_text: bearings being held against rotation. These diagonal bearings cause the end
pieces of the screen to slant outwards at the top so that when the screen is working
the bottom part or underside of it is approximately in a straight line whilst the top
tapers off from its middle to each end, so that when revolved it causes a slight
inovement of the wires, so that any grain held between the wires will drop out
from the sides or the upper part of the screen as it revolves.
At the end of the screen where the grain is fed into it, the diagonal end bearing
is fixed, so that it cannot be moved end ways but the diagonal bearing at the other
end can be moved end ways for adjusting the length of the screen.
The screen can be adjusted in length by having its wires moved closer together
r farther apart by a screw placed inside its spindle at one end and having two
threads, one of which engages in the central or driving centre and the other in one
of the outside end centres, whilst the other end of the screw-spindle is fixed as
regards end movement relatively to the screen spindle.
To enable the invention to be fully understood we will describe the same by
reference to the accompanying drawing, in which :-
Figure 1 is an elevation partly in section of our improved screen; and,
Figure 2 is a longitudinal section :
Figures 3 and represent end views of the screen without any supports or
framing.
b
a is the framing of the screen, b is the shaft or spindle which is hollow and
supported at its ends in bearings c, c, and d is the body of the screen or the screen
proper which is of larger diameter at the middle than at the ends and is supported
upon the shaft by the two end pieces e, e¹ and the centre piece f, which centre
piece is mounted upon the central spindle so, that it revolves with it but can be
moved longitudinally upon it. On the end of the spindle b carrying the end piece e
is a sleeveg which is attached to a casting or spout secured to the frame a
carrying the bearings of the spindle and upon which the said end piece e rotates,
and upon the end of the spindle carrying the end piece el is another sleeve g¹ upon
which the said end piece e' rotates. This sleeve g' is not fixed rigidly as is the
sleeve but an armi is attached to it which projects outside the screen and can
slide on a fixed bar j. It will be noticed that these two sleeves are bored out at
an angle to their axes so that the end pieces will be supported in inclined positions.
At the inside end of the sleeve g¹ is another sleeve k having in connection with it
a nut projecting inside the hollow spindle and with which engages a screw m;
and in connection with the sliding centre piece f is a nut n also projecting into the
hollow spindle and with which engages a screw o. These screws are in one piece
but of two different pitches, say in the ratio of two to one or thereabouts, and
extend at one end p outside the spindle 6 being held in position by a cap 9.
is a pulley through the medium of which motion is imparted to the screen,
and s, s are the ordinary conveyor blades within the screen.
The operation of the screen hereinbefore described is similar to that of other
rotary screens, that is to say, as the screen is rotated grain is introduced through
the spout h at one end and gradually worked towards the other end: owing, how-
ever, to the fact that the end pieces are at an angle to each other, the wires forming
the screen proper will be pulled apart at the top and again compressed at the
bottom, so that any grains that do not pass through the screen but lodge between
the wires will be allowed to drop as the wires are opened or moved apart.
In order to adjust the screen according to the grade of corn required the double
screw m, o is turned to lengthen or shorten the screen as required and as the
screw m in connection with the moving end of the screen is double the pitch of the
screw o in connection with the centre piece f and as the other end of the screen is
fixed as regards longitudinal movement it follows that when the screw is turned the
lengthening and shortening takes place proportionately all over the screen.
Although, as shewn in the drawing, the sliding end of the screen has the sleeve
on which it revolves held by an arm extended to the outside and sliding on a bar,
there are other methods by which this sleeve can be held against rotation, namely

page_text: by causing it to slide on another sleeve attached to the machine-frame, which can
have a key on it to prevent the first named sleeve from turning round; or jointed
links can be attached to the sleeve at one end, the other end being attached to the
frame so as to prevent the sleeve from turning round and at the same time allow it
to be moved lengthways. Another plan is to carry an arm down from the sleeve
and attach a heavy weight to it so that the weight prevents the sleeve from turning
round while at the same time it can be moved sideways as in the plan illustrated
and described. The latter plan has also the advantage, as the weight oscillates a
little, of allowing a slight vibration of the screen, which vibration will help the corn
the better to dislodge from the wires.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. A circular corn screen having a central hollow spindle containing a screw for
adjusting the distances between the wires, and having its end pieces running on
sleeves or bearings placed at an angle to the said spindle and, at the middle of its
length where it is larger in diameter than at the ends, a centre piece rotating with
the spindle, the said sleeves or bearings being held against rotation and one of them
being adapted to be moved longitudinally upon the spindle, substantially as
described.
2. A cylindrical corn screen so constructed that the middle is larger in diameter
than the ends, the said ends being carried on bearings placed at an angle so as to
cause the wires at the bottom of the screen to be closer together than those at the
top, and the lower part of the screen to be nearly level whilst the top inclines from
the centre of its length to each end, substantially as described.
3. The improved corn screen constructed and arranged substantially in the
manner hereinbefore described and illustrated in the accompanying drawing.
Dated this 8th day of December 1892.
G. F. REDFERN & Co.,
.4, South Street, Finsbury, London, Agents for the Applicants.