AN IMPROVED ARRANGEMENT OF SCREENING OR DRESSING MACHINE
Year: 1884

page_text: I ROBERT BOBY of St Andrew's Works, Bury St Edmunds in the County of
Suffolk, Agricultural Implement Maker, do hereby declare the nature of my
invention for AN IMPROVED ARRANGEMENT OF SCREENING OR DRESSING MACHINE
to be as follows:-
The object of this invention is to simplify the construction and improve the
action of screening and dressing machines. It applies more particularly to the
construction of dressing machine for which I obtained Letters Patent bearing date
17th April 1867 N° 1134 but may be readily adapted to machines of other forms.
The riddle which has hitherto received a reciprocating motion in a direction
transversely to that of the screen I now arrange to receive a motion parallel with
that of the screen and I apply to its grids an arrangement of cleaning apparatus
similar in action to that hitherto applied to the screen only. The riddle which is
situated above the screen and is intended to receive from the supply hopper the
grain to be dressed, is provided, with two or more grids which are removable. The
riddle is supported at its four corners by pendent elastic arms. The sides of the
frame are slotted longitudinally to receive cross shafts which are provided with
clearing discs for entering between the wires of the grids and clearing them of any
matters which may become fixed therein.
1
These cross shafts are fitted into supports in the main framing of the machine
and remain stationary while a traverse motion is given to the riddle. The screen
which is mounted as heretofore and provided with stationary clearers receives a
traverse motion from a transverse crank shaft it being connected therewith at its
rear end by a central crank rod. Pivotted to this rod is a link which connects with
the front end of the riddle. Thus both the riddle-and-the-screen are actuated
directly from the same crank shaft and to the same amount.
i
The riddle carries near its front end an inclined board onto which the grain
supplied to the hopper falls and by which it is guided to the upper grid.
Those matters which will not pass through the grid are caused to discharge from
the back of the riddle and clear of the screen below but the smaller matters pass
to the lower grid and if not intercepted thereby, they fall through the grid onto
the next if there be more than two and thence onto an inclined board carried by
the riddle.
In passing through the riddle the grain is subjected to the action of a blast of air
produced by a fan which is mounted on the crank shaft. The grain thus partially
freed from extraneous matters falls from the inclined board onto the screen which
completes the dressing it being aided by the air blast of the fan.
Tihim 1nt dan of MT 1001.

page_text: ⚫ I ROBERT BOBY of St Andrews Works, Bury St Edmunds, in the County of
Suffolk, Agricultural Implement Maker do hereby declare the nature of my.
invention for AN IMPROVED ARRANGEMENT OF SCREENING OR DRESSING MACHINE
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :—
The object of this invention is to simplify the construction and improve the
action of screening and dressing machines. My improvements apply more
particularly to the construction of dressing machine for which I obtained Letters
Patent bearing date 17th April 1867 N° 1134; but may be readily adapted to
machines of other forms.
The riddle, which has usually received a reciprocating motion in a direction
transversely to that of the screen, I now arrange to receive a motion parallel with
that of the screen, and to the riddle thus actuated I apply an arrangement of
clearing apparatus similar in action to that hitherto applied to the screen only. The
reciprocating motion of both the riddle and screen I obtain from a central crank,
and I am thus enabled greatly to simplify the driving gear.
In Sheet I of the accompanying drawings,.
Fig 1 is a longitudinal sectional elevation of my improved screening and
dressing machine, and Fig 2 is a transverse section of the same.
In Sheet II, Fig: 3 is a detached sectional view of one of the riddle grids with
the clearers in connection therewith; and
Fig 4 is a section of the same parts, taken at right angles to Fig: 3.
:
: A is the framing of the dressing inachine; B is the screen constructed and carried
by wooden spring hangers, and fitted with clearers for keeping open the grid as
heretofore. C is the riddle, also suspended from, wooden spring hangers, and
situate immediately over the rear end of the screen. D is a hopper for supplying
grain to the riddle, and E is a transverse shaft with a central crank for giving a
reciprocating notion to both the screen and riddle through the connecting rods e
and el respectively.
J.
This crank shaft E carries. a divided fan or blower F, which serves to throw
Ta blast of air into the open front of the riddle, and also onto the rear of the
screen.
0.
The riddle, which is intended to receive from the supply hopper D the grain to
be dressed, is provided with two grids cc, which are constructed in the well known
manner, and, are removable to allow of their being replaced by grids of finer or
coarser gauge to suit the work in hand.
The sides of the riddle are slotted longitudinally to receive transverse arms C2,
which stand out from brackets a. of the main framing, and serve to carry
longitudinal notched bars C³, which support in position the clearers C, as shewn
at Figs. 3 and 4. These clearers' consist of discs. C strung onto the rods C6, and
spaced to correspond to the gauge of the grid with which they are used for clearing
such grids of any matter which may become fixed therein. Each grid of the
riddle, it will be understood, is similarly furnished with clearers. The transverse
arms C2 and the parts which they carry are all stationary, while a short traverse
motion is given to the riddle. This motion is obtained through the rod e¹, which
is connected at one end to the front of the riddle, and at its other end to the crank
rod e. This crank rod connects with the rear of the screen, and thus serves to
transmit a reciprocating motion, derived from the crank shaft E, to both the riddle
and the screen.

page_text: The riddle carries near its front end an inclined board C7, onto which the grain
supplied from the hopper D falls, and by which it is guided to the upper grid.
Those matters which will not pass through the grid are discharged from the back
of the riddle and clear of the screen below, but the smaller matters pass to the
lower grid, and if not intercepted thereby, they fall through the grid onto the next
(if there be more than two), and thence onto an inclined board carried by the
riddle.
In passing through the riddle, the grain is subjected to the action of a blast of
air produced by the fan F, the trunk case of which leads the air to the open-front
of the riddle.
The grain, thus partially freed from extraneous matters, falls from the inclined
board onto the screen B, which completes the dressing, it being aided by the air
blast of the fan.
The means for operating the riddle from a central crank is applicable also to
dressing machines in which the riddle has a transverse motion, by the simple
introduction of a bell crank lever.
This is illustrated in partial plan view at Fig 2*, Sheet I. In this figure e is
the crank rod for actuating the screen, and C is the riddle, to the side of which
the rod e¹ is connected. Instead of the rod e¹ being directly attached to the rod e,
as shewn in Fig 1, a bell crank lever e³ is interposed between them, its arms being
pivotted, the one to the rod e¹, and the other to a rod e³, which leads down to and
connects with the rod e. This bell crank lever e rocks on a pivot carried by a
cross bar et
It will now be understood that as a reciprocating motion is given to the rod e
by the throw of the crank shaft E, the bell crank lever will be caused to rock and
impart, through the rod el, a lateral reciprocating motion to the riddle.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is :-
First. The employment, in a screening and Dressing machine, of a longitudinally
reciprocating riddle fitted with stationary clearers as and for the purpose above
described.
Secondly. Actuating the screen and riddle of screening and dressing machines
from a central rotating crank as described, whereby the arrangement of driving
gear is greatly simplified.